Posts belonging to Category 'solar hot water heater'

Tankless Solar Panel Inverter batterey Water Heater

Question:

Solar Panel Inverter battereyYou are sort of right but mostly wrong.

And yet, you have only supplied points which agree 100% with mine Solar Panel Inverter batterey Thanks for answering my rhetorical questions so coherently. My main point is that power companies have an interest in getting their customers to live within the company’s means, because that approach probably costs less than buying more capacity or buying power from “competitors.” So there is no inconsistency with power companies paying money for energy-saving programs, as implied by an earlier poster. -mod.

Response:

“The bitterness of poor quality remains long after the sweetness of low price! Ben Franklin” – Hide quoted text — Show quoted text – Only if you want to fill a bucket with a given temperature of water. If you are (for example) taking a shower,Solar Panel Inverter batterey then a reducing the wattage of the heater will cause you to lower the flow to keep the temperature right. You won’t spend (much) longer in the shower, so it may be a net energy saving. If you are running a hotel, then ‘undersized’ water heaters might save you a moderate amount of money. Sounds like the same thing could be accomplished with a low flow showerhead. If the shower sucks I’m out of there much faster. IMO, this is precisely what holds back legitimate conservation efforts like solar water heaters and the like. People are sold some lower priced magic device. They buy it based on economics, psuedoscience, or thinking it’s possible to get something for little or nothing. Then they feel they need to defend their mistake for a while. They pretend they’re not suffering, until it breaks, then they go back to what they had in the first place, forever left with a bitter taste in their mouth about energy efficiency. Timers, low flow showerheads, tankless heaters. They’re all based on a mindset of “lack” rather than “abundance.” I’ve seen it first hand selling Solar Water Heaters. The miserly husband won’t admit he was wrong. Has all sorts of excuses. “I never run out of hot water.” “Cold showers are healthier.Solar Panel Inverter batterey” While the wife is there staring holes in him. It’s my guess he’ll be taking alot of cold showers.

Response:

Why would a power company sponsor something that saves 50 percent of the energy a home uses to heat water? So they don’t have to build more power plants, so the can’t sell power to other states at a premium? You got it exactly. They make more money selling power from the equipment they already have (which is already completely at least partly paid for) than by floating bonds to finance the manufacture of more capacity. How much more could they charge a neighboring utility than their own customers, for it to make economic sense to build a new plant for that specific market? If they can get their own customers to save energy, then maybe they CAN sell power to other states at a premium without building more plants. Then they make more money and consequently won’t have to charge their ratepayers as much. Solar Panel Inverter batterey

You are sort of right but mostly wrong.Solar Panel Inverter batterey If they could charge a neighboring utility so much more then wouldn’t it make sense to build a new plant to sell the them along with the increased use of your own buyers? After all if they can only sell 100 units now because that’s all they can spare but could sell 1000+ unit if they could produce it why not make it to sell? Two reasons. First is the fact that if it worked this way the other utility would build its own plant and tell the other one to shove off. But the real reason is. . . The capital outlay to build a new plant is going to take a LONG time to pay off and show a profit IF you can find some place willing to let you build it. So your thought of they want more ‘bang for the buck’ at each plant is correct. Ever wonder why California HAS to buy power from out of state? Its because everyone wants power but no one wants them to build a power plant near them. Since they don’t want the plants they have to pay what ever the people who build the plants outside the state wants them to. Its called supply and demand. Say you were in a group that went for a hike in the woods in the summer but didn’t want the bother of carrying water. At the end of the trail you are really, really, REALLY thirsty. Let’s say that I’m sitting at the trail end with a couple of extra liter bottles of water I had carried all along the trail. You come up and want to buy some water. I paid $1/bottle so you think paying $1.50 would be fair, after all I should get some profit. But before you can get to me someone else in your group offers $5 for a bottle. Now which one of you do you think is going to be drinking the water? If I have enough bottles how much do you think you are going to pay for a bottle? Are you being screwed? No. You could had all the water you wanted for $1/bottle, all you had to do is buy it and carry it with you. You made the decision not to buy it before and/or not to carry it with you so you are now paying the price of that decision. IOW,Solar Panel Inverter batterey in the real world stupidity and shortsightedness cost.

Response:

But, solar won’t work everywhere. For example in the past three days, there have been maybe an hour of sun in total, with that being pretty anemic due to high cloud.

I guess I’m so bitter because here in Florida there’s nothing but sun. It’s called the “Sunshine State” for God’s sake! Yet people still are looking for any and every other way, other than the obvious. — All the best,Solar Panel Inverter batterey

Response:

“Tests, sponsored by Virginia Power, were performed at Old Dominion University in Norfolk, Virginia. The GFX was paired with various electric water heaters. The tests indicated that the $180 device can save up to 50 percent of the energy a home uses to heat water. In fact, when the GFX was installed, the water heater’s upper elements never energized, something the test report calls “a significant result.” Why would a power company sponsor something that saves 50 percent of the energy a home uses to heat water? So they don’t have to build more power plants, so the can’t sell power to other states at a premiumSolar Panel Inverter batterey

Response:

You got it exactly. Solar Panel Inverter battereyThey make more money selling power from the equipment they already have (which is already completely at least partly paid for) than by floating bonds to finance the manufacture of more capacity. How much more could they charge a neighboring utility than their own customers, for it to make economic sense to build a new plant for that specific market? If they can get their own customers to save energy, then maybe they CAN sell power to other states at a premium without building more plants. Then they make more money and consequently won’t have to charge their ratepayers as much. -mod.

Response:

<snip There are other ways, for example heat-exchangers to recover heat from the waste water could dramatically reduce power bills for showers.

Solar Panel Inverter batterey Device Recovers Waste Energy From Drain Water The Department of Energy wants electric hot water production to be substantially more efficient by the year 2000, but the chances of pulling that off are slim with current water heater technology. Anything that helps builders meet the goal is bound to be well-received. That’s where the GFX comes in. The GFX is a counterflow heat exchanger. It consists of a coil of 1/2- or 3/4-in. copper tubing that’s tightly wrapped around a 3- or 4-in. diameter copper pipe. The device is installed vertically in the plumbing system. As waste water flows down through the vertical pipe section, it naturally clings to the walls of the pipe. More than half the waste water’s heat energy is transferred through the copper pipe and tubing to the incoming cold water. There is no pump and no storage tank. The device uses no electricity, so there is no operating cost. GFX only works when the drain and supply lines are being used simultaneously–as when someone is taking a shower. Tests, sponsored by Virginia Power, were performed at Old Dominion University in Norfolk, Virginia. The GFX was paired with various electric water heaters. The tests indicated that the $180 device can save up to 50 percent of the energy a home uses to heat water. In fact, when the GFX was installed, the water heater’s upper elements never energized, something the test report calls “a significant result.” GFX has been demonstrated in several model energy-efficient homes including one operated by the National Association of Homebuilders’ Research Center. — Steve Spence Subscribe to the Renewable Energy Newsletter & Discussion Boards. Read about Sustainable Technology: Solar Panel Inverter batterey

Response:

Only if you want to fill a bucket with a given temperature of water. If you are (for example) taking a shower, then a reducing the wattage of the heater will cause you to lower the flow to keep the temperature right. You won’t spend (much) longer in the shower, so it may be a net energy saving. If you are running a hotel, then ‘undersized’ water heaters might save you a moderate amount of money. Sounds like the same thing could be accomplished with a low flow showerhead. If the shower sucks I’m out of there much faster.

If you put a lower flow showerhead on, then you don’t have the option of a high flow cooler shower (that some people like). The right solution is probably to charge for power used, and install a big heater. IMO, this is precisely what holds back legitimate conservation efforts like solar water heaters and the like. People are sold some lower priced magic device. They buy it based on economics, psuedoscience, or thinking it’s possible to get something for little or nothing. Then they feel they need to

But, solar won’t work everywhere. For example in the past three days, there have been maybe an hour of sun in total, with that being pretty anemic due to high cloud. There are other ways, for example heat-exchangers to recover heat from the waste water could dramatically reduce power bills for showers. Solar Panel Inverter batterey

Response:

Only if you want to fill a bucket with a given temperature of water. If you are (for example) taking a shower, then a reducing the wattage of the heater will cause you to lower the flow to keep the temperature right. You won’t spend (much) longer in the shower, so it may be a net energy saving. If you are running a hotel,Solar Panel Inverter batterey then ‘undersized’ water heaters might save you a moderate amount of money.

Sounds like the same thing could be accomplished with a low flow showerhead. If the shower sucks I’m out of there much faster. IMO, this is precisely what holds back legitimate conservation efforts like solar water heaters and the like. People are sold some lower priced magic device. They buy it based on economics, psuedoscience, or thinking it’s possible to get something for little or nothing. Then they feel they need to defend their mistake for a while. They pretend they’re not suffering, until it breaks, then they go back to what they had in the first place, forever left with a bitter taste in their mouth about energy efficiency. Timers, low flow showerheads, tankless heaters. They’re all based on a mindset of “lack” rather than “abundance.” I’ve seen it first hand selling Solar Water Heaters. The miserly husband won’t admit he was wrong. Has all sorts of excuses. “I never run out of hot water.” “Cold showers are healthierSolar Panel Inverter batterey

Response:

When 65F is very very hot compared to the outside temperature, the electric heat efficiency is higher, and the advantage of <snip Short of a heat pump or solar,wouldn’t multiple, smaller heaters solve the “long run”Solar Panel Inverter batterey

Response:

When 65F is very very hot compared to the outside temperature, the electric heat efficiency is higher, and the advantage of a heat pump is much less.

This just reminded me. I sold Solar to a customer who had 15 gallon electric tanks in each bathroom, and under the kitchen sink. He initially installed them to save space in the closet where his 40 gallon heater was. I would think this might be ideal. I can’t remember exactly what motivated him to want Solar. He was a little eccentric. I know we installed the 80 gallon storage tank in his attic and got rid of all the other heaters. Solar Panel Inverter battereyIf memory serves me, I think that’s what closed the deal. He like the the hot, bulky water tank would be out of his air-conditioned living area and put in the attic, where in Florida, it’s deathly hot anyway. Short of a heat pump or solar,wouldn’t multiple, smaller heaters solve the “long run” loss/waiting problem, reduce tank surface area, and allow a slower, more efficient, heating of the water? — All the best, www.iwantsolar.com – Hide quoted text — Show quoted text – Sandy. this is a fundamental error of science. (The claim that electric heat is “100 % efficient” because 1 watt in produces a joule of heat energy.) The problem is that this is not a reversible process, though it has nothing to do with the rate of change, as Don suggested. It is because a heat pump, (assuming a near perfect one without the usual losses from heat leakage and friction), operates at a 100% thermodynamic efficiency, and can pump hundreds of joules of “low grade” heat (if the temperature difference is small enough), with only a few joules of high grade heat (where the temperature difference is very high). The electric heat is nearly 100% efficient when producing heat at extremely high temperatures. But it is a huge thermodynamic loss, waste of energy, loss of efficiency, to let this super hot heat warm a house up just a tiny bit. You really need that heat pump to even get close to 80% thermodynamic efficiency, except in Siberia in mid winter, perhaps. When 65F is very very hot compared to the outside temperature, the electric heat efficiency is higher, and the advantage of a heat pump is much less. … Tankless is fundamentally and thermodynamically flawed in that a

Response:

Changed out the old electric water heater for a new tankless on demand system. Electric bill has dropped $30.00 a month. System cost $500 and my old water heater needed replacement which would of cost $200 anyway. Solar Panel Inverter batterey Payback in utility savings is less than a year for us!

The laws of physics dictate that you can only save what was being lost through the walls of your old tank. Thirty dollars is a hefty loss. How old was your previous tank? Are you saving money by forced concervation, i.e. are you running out of hot water, or have you noticed that you’ve changed your habits at all to accomodate the new heater? A well insulated tank should only loose around $10/mth in heat, unless you’re in a really cold climate, or you had a really old poorly insulated water heater. — All the best, www.iwantsolar.com

Response:

Sometimes I think people get too carried away. I believe in the KISS (Keep It Simple, Stupid) principal. If everyone would use a simple batch heater to preheat the water before it got to the water heater, then there would be a lot of savings, and the outlay would be very low. That is one of the most cost effective uses of solar, most return, least outlay, quickest payback. However, most people going solar seem to think all or nothing. The advocates seem to ignore it for systems that cost thousands of dollars and payback over 10 or 20 years or more. A batch heater and your old HW heater are most likely cheaper to operate than a hot water on demand system, and costs less! If you get a new water heater that is more efficient the costs will be reduced more. Kip

Solar Panel Inverter batterey

Mr. Dully says it goes on the ground, but I wonder about the bang for the buck. It would only work in non-freezing weather. He says start with a “discarded water heater tank,” but most of those leak, and “stripping it down and painting it black” is lots of work. Add reflectors and insulation and some old storm windows on top and “a hinged cover or quilt” for nighttime… How many people would move the cover every day? Movable insulation didn’t move much inside passive solar houses. Won’t the quilt get moldy? We might have 90% solar hot water with lots of collection area and storage. Picture a large insulated shoebox on the lawn under a linear parabolic reflector, with a PV-powered pump to move water up through a shallow target trough near the north edge during the day. The water inside the box would be unpressurized, with an RV pump in the house…Solar Panel Inverter batterey

Response:

Many States prohipit HOA from restricting Solar HW or PV systems. – Hide quoted text — Show quoted text – If this Solar Panel Inverter batterey

Response:

- Hide quoted text — Show quoted text – I don’t see how I could convince even .00000001 % of the American population to put that on their roof. Most suburban homes are now strictly regulated by home owner associations, and county inspectors, an old biddies (see http://www.miami.com/mld/miamiherald/4370899.htm ) drive around just looking for those sort of monstrosities. If one is going to go through the initial trouble of hiring a contractor and pulling a permit, why would they impair the value of and salability their home? As I Contractor I wouldn’t touch it,and as a Real Estate Agent, I cringe when I see something like that. If you hire a Realtor to sell your home, something like that would have to be disclosed and remedied before it changes hands. — All the best, Stephen Horrillo www.iwantsolar.com

Perhaps I’m missing something. You’ve got a website devoted to solar water heating, but you haven’t heard of batch heaters? You’re a contractor who hasn’t considered ground mounting a solar device? You’re a RE agent who can’t convince 3 one-hundredths of a person in the US to install a batch heater? (help me with the math somebody, my calculator ain’t got that many zeros) :-) I question your statement that “most suburban homes are strictly regulated by HOA”. But if it were true, you should know that even the yard nazis often have limited authority when it comes to renewable energy, TV signal reception, etc. I clicked on the free-survey information link on your site, but it only leads to a blank email. Are you selling something? Wayne

Response:

Yard “nazis” are abundant in many neighborhoods. City hall passes ordinances all the time (IMHO jsust to get them off their backs) based upon their gripes. Many complexes DO have a no outdoor antenna policy. Bulding codes can have so many hurdles to complete that a Solar Installation gets abandoned complying with the non-solar part of the project. Our communith as very small back yards (limits on ground coverage rules are consumed by the house and required Garage/driveway). There areSolar Panel Inverter batterey

Response:

Yard “nazis” are abundant in many neighborhoods. City hall passes ordinances all the time (IMHO jsust to get them off their backs) based upon their gripes.

Yard nazis generally refer to enforcers of CC&Rs. While the majority of residents in HOAs (home owner associations) seem to complain mightlily about rule enforcement, they all signed a contract before moving in. HOAs are still spreading like wildfire last I heard. I guess it’s because people like the concept. The article mentioned that everybody seems to like eforcement, until the rules apply to them. Go figger. BTW, I’ve lived in a regulated development, served on some boards, and written enforcement letters. Gawd I wish whine….er, people, would learn to read *before* signing. Many complexes DO have a no outdoor antenna policy.

Don’t know about regular antennas, but satellite dishes below a certain size are permitted regardless of HOA rules. If I lived in development which banned dishes, I’d put one up just to irritate the yard nazis. Bulding codes can have so many hurdles to complete that a Solar Installation gets abandoned complying with the non-solar part of the project. Our communith as very small back yards (limits on ground coverage rules are consumed by the house and required Garage/driveway). There are “shadow cast” rules where again the house as already at the edge of the permitted envelope (new “monster homes”).

My condolences. Apartment dwellers might envy your space though. :-) Notice they did not say NP to solar :/) ?

Is “NP” no problem? Whatever. You can probably find out at homepower.com if you have state laws about renewable energy which trump local ordinances. Wayne

Response:

A batch heater is basically a black water tank in a glass enclosure that warms up the water by the sun light. When I say pre heater I mean to feed the output of this tank to your normal water heater. The idea is that if the batch heater warms the water to temperatures above the ground water you are saving money, because instead of the water heater warming water from 55 degrees to 120 degrees for your hot water, you are only heating it the last few degrees. It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. So even if you are only raising the temperature from 55 to 88.5 degrees you save about 50% of your energy. If you can raise the temperature of the water to say 100 degrees, you get about a 70% savings. The main thing is it is extremely simple and low cost. You don’t need a bunch of coils. If the box is well insulated the mass of water will keep it from freezing in the winter, (be sure to insulate the pipes as they come out.) It will only cost a couple of hundred dollars, and you will probably get your money back in one or two years in energy savings. And there is no maintenance. Solar Panel Inverter batterey

- Hide quoted text — Show quoted text – A batch preheater is also simple enough that almost anyone can benefit from it immediately without a big cash outlay. I think it would be more energy savings for 50% of the houses in the United States to have batch preheaters than to have 0.00001% of the houses to be totally off the grid. Pardon my ignorance but what is a batch pre-heater? I seached the internet and nothing came up. — All the best, Stephen Horrillo www.iwantsolar.com

Response:

Notice they did not say NP to solar :/) ? Is “NP” no problem? Whatever. You can probably find out at homepower.com if you have state laws about renewable energy which trump local ordinances.

Solar Panel Inverter batterey

Response:

… The main thing is it is extremely simple and low cost.

… Of course, one of the factors that has helped to slow the general rush to install solar water heaters of any kind is that natural gas is very inexpensive. A gas water heater is extremely simple, low cost and fairly fuel efficient today. If you live in an area that has a natural gas utility system then water heating is likely already a very low cost item for you. Even more low cost when you consider that most places will require you to at least own a backup water heater, even if it’s not turned on, when you install a solar water heating system. Solar Panel Inverter batterey

Response:

I clicked on the free-survey information link on your site,Solar Panel Inverter batterey but it only leads to a blank email. Are you selling something? no

Would you please explain what your survey is then. Wayne

Response:

Yard nazis generally refer to enforcers of CC&Rs. While the majority of residents in HOAs (home owner associations) seem to complain mightlily about rule enforcement, they all signed a contract before moving in. HOAs are still spreading like wildfire last I heard. I guess it’s because people like the concept. They also work with the City who will refuse to issue a building permit until you show them written permission from the builder and or HOA. Legal or not, they’ve done it to me many times over.

That happened to me once. I was at the county office to get a building permit. They claimed they needed an OK from the HOA first. LOL. I made a short speech through clenched teeth, and they turned over the permit. These would-be dictators act like they do because people put up with it. Wayne

Response:

- Hide quoted text — Show quoted text – Yard nazis generally refer to enforcers of CC&Rs. While the majority of residents in HOAs (home owner associations) seem to complain mightlily about rule enforcement, they all signed a contract before moving in. HOAs are still spreading like wildfire last I heard. I guess it’s because people like the concept. They also work with the City who will refuse to issue a building permit until you show them written permission from the builder and or HOA. Legal or not, they’ve done it to me many times over. That happened to me once. I was at the county office to get a building permit. They claimed they needed an OK from the HOA first. LOL. I made a short speech through clenched teeth, and they turned over the permit. These would-be dictators act like they do because people put up with it. Wayne

Are these HOA’s like what we used to call “covenant neighborhoods” where even exterior paint color is regulated by contract? What are the benefits? Jack

Response:

It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees.

Exactly twice.

Response:

It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. Exactly twice.

Solar Panel Inverter batterey

Response:

It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. Exactly twice.

Response:

That they were full of shit. There was no county law requiring prior approval by the HOA. Some over-zealous board member from our association had visited the building department, and asked them to insist on prior approval from the association. The county workers had been complying, and probably still are whenever the applicant doesn’t speak up. Officials can’t just make up new rules and procedures. There are rules and procedures to cover that process. :-) Wayne

Response:

It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. Exactly twice.

Except that that disregards heat losses – in the real world, you’ll use more than twice the amount of heat, because the losses are proportional to the temperature difference raise to the power 4/5. — May glorious Shamash make his face to shine upon you Gilgamesh of Uruk now residing in the Kingdom of Mercia

Response:

It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. Exactly twice. Table B-3 of the $14.95 1998 Schaum’s Outline on heat transfer says it takes 0.9988 Btu/lb to raise a pound of water 32.5 F from 51.75 to 84.25, vs 0.9980 from 87.75 to 120.45, a difference of 0.026 Btu

Oops. My mistake. (bunch of 4th decimal place weenies

Response:

TSolar Panel Inverter batterey

- Hide quoted text — Show quoted text – It takes roughly twice the BTU’s to raise an amount of water 65 degrees as to raise it 32.5 degrees. Exactly twice. Except that that disregards heat losses – in the real world, you’ll use more than twice the amount of heat, because the losses are proportional to the temperature difference raise to the power 4/5. — May glorious Shamash make his face to shine upon you Gilgamesh of Uruk now residing in the Kingdom of Mercia

Response:

I’m sure you mean 0.9988 Btu/lb/deg-F, not 0.9988 Btu total daestrom

Response:

- Hide quoted text — Show quoted text – That happened to me once. I was at the county office to get a building permit. They claimed they needed an OK from the HOA first. LOL. I made a short speech through clenched teeth, and they turned over the permit. These would-be dictators act like they do because people put up with it. Must have been a good speech or a wimpy official. What did you say to get them to back down? That they were full of shit. There was no county law requiring prior approval by the HOA. Some over-zealous board member from our association had visited the building department, and asked them to insist on prior approval from the association. The county workers had been complying, and probably still are whenever the applicant doesn’t speak up. Officials can’t just make up new rules and procedures. There are rules and procedures to cover that process. :-) Wayne

They may have no legal authory to make up new rules and procedures, but it is certainly common for them to do so. It works as long as they don’t go up againts someone who knows the real rules, and stands up to them. Mostly they back down, but often they will go to the mat with you on such things, just cause they can.

Solar Panel Inverter batterey

Response:

I worded it wrong. I meant, when I used them in hotels in Europe, gas fired too, I noticed that it started out feeling hot but cooled down as I stayed in the shower, i.e. I probably got acclimated to the temperature. It forced me to lower the flow rate to get a higher temperature. Worked fine to fill a tub, but was a definite sacrifice when I wanted a shower.

No I do not take a cold showers! You simply buy the unit appropiate to your demand and climate condition. Input water tempeture is of concern as units are sized by gph and tempeture raise. The energy cost to heat water is exactly the same between a tankless unit and a conventional water heater. When you are using hotwater! Where you are saving money is a tankless unit uses no energy when there is no demand. While a conventional water heater uses significant energy to keep water at tempeture 24/7. How much that cost depends tempeture it is much more expensive in a 20 degree garage in the winter than at 90 degrees in the summer. The other major advantage with a tankless system is size! About 10% of conventional water heater, which gives you many more placement options. Allowing you placement closer to use areasfor lower energy loss! Ken

Response:

Yard nazis generally refer to enforcers of CC&Rs. While the majority of residents in HOAs (home owner associations) seem to complain mightlily about rule enforcement, they all signed a contract before moving in. HOAs are still spreading like wildfire last I heard. I guess it’s because people like the concept. They also work with the City who will refuse to issue a building permit until you show them written permission from the builder and or HOA. Legal or not, they’ve done it to me many times over.

Response:

- Hide quoted text — Show quoted text – Changed out the old electric water heater for a new tankless on demand system. Electric bill has dropped $30.00 a month. System cost $500 and my old water heater needed replacement which would of cost $200 anyway. Payback in utility savings is less than a year for us! The laws of physics dictate that you can only save what was being lost through the walls of your old tank. Thirty dollars is a hefty loss. How old was your previous tank? Are you saving money by forced concervation, i.e. are you running out of hot water, or have you noticed that you’ve changed Err, ‘tankless’. No tank, heat-on-demand. It’s really, really hard to run out of water. your habits at all to accomodate the new heater? A well insulated tank should only loose around $10/mth in heat, unless you’re in a really cold climate, or you had a really old poorly insulated water heater. — Stirling. —— Prosperity and ruin issue from the power of the tongue. Therefore, guard yourself against thoughtless speech.

If your old heater was not working well, then it would have been wasting energy, so that would account for at least part of the difference – plus you have presumably replaced the timer/thermostat and that, again, would reuce your losses. — May glorious Shamash make his face to shine upon you Gilgamesh of Uruk now residing in the Kingdom of Mercia

Response:

… I wish! My water comes into my house at about 45 deg F. Last I looked there wasn’t an electric unit I could install that would increase the hot water to 105 for a shower. Ok, some numbers off the top of my head. Let’s say you are taking a shower using 2 gal/minute. Your water is going from 45F to 105F or 60F. The water heater(s) need to raise the temperature of 120 gallons (8.34×120=1001 lbs) 60F per hour. One BTU raises one lb of water one deg F so this means we would need (1001×60=) 60060 BTU per hour

Solar Panel Inverter batterey

Response:

<snip There are other ways, for example heat-exchangers to recover heat from the waste water could dramatically reduce power bills for showers.

http://www.oikos.com/esb/49/gfx.html Device Recovers Waste Energy From Drain Water The Department of Energy wants electric hot water production to be substantially more efficient by the year 2000, but the chances of pulling that off are slim with current water heater technology. Anything that helps builders meet the goal is bound to be well-received. That’s where the GFX comes in. The GFX is a counterflow heat exchanger. It consists of a coil of 1/2- or 3/4-in. copper tubing that’s tightly wrapped around a 3- or 4-in. diameter copper pipe. The device is installed vertically in the plumbing system. As waste water flows down through the vertical pipe section, it naturally clings to the walls of the pipe. More than half the waste water’s heat energy is transferred through the copper pipe and tubing to the incoming cold water. There is no pump and no storage tank. The device uses no electricity, so there is no operating cost. GFX only works when the drain and supply lines are being used simultaneously–as when someone is taking a shower. Tests, sponsored by Virginia Power, were performed at Old Dominion University in Norfolk, Virginia. The GFX was paired with various electric water heaters. The tests indicated that the $180 device can save up to 50 percent of the energy a home uses to heat water. In fact, when the GFX was installed, the water heater’s upper elements never energized, something the test report calls “a significant result.” GFX has been demonstrated in several model energy-efficient homes including one operated by the National Association of Homebuilders’ Research Center. — Steve Spence Subscribe to the Renewable Energy Newsletter & Discussion Boards. Read about Sustainable Technology: http://www.green-trust.org

Response:

Table B-3 of the $14.95 1998 Schaum’s Outline on heat transfer says it takes 0.9988 Btu/lb to raise a pound of water 32.5 F from 51.75 to 84.25, vs 0.9980 from 87.75 to 120.45, a difference of 0.026 Btu I’m sure you mean 0.9988 Btu/lb/deg-F, not 0.9988 Btu total

Yes, and 120.25 vs 120.45. Nick

Response:

“The bitterness of poor quality remains long after the sweetness of low price! Ben Franklin” – Hide quoted text — Show quoted text – Only if you want to fill a bucket with a given temperature of water. If you are (for example) taking a shower, then a reducing the wattage of the heater will cause you to lower the flow to keep the temperature right. You won’t spend (much) longer in the shower, so it may be a net energy saving. If you are running a hotel, then ‘undersized’ water heaters might save you a moderate amount of money. Sounds like the same thing could be accomplished with a low flow showerhead. If the shower sucks I’m out of there much faster. IMO, this is precisely what holds back legitimate conservation efforts like solar water heaters and the like. People are sold some lower priced magic device. They buy it based on economics, psuedoscience, or thinking it’s possible to get something for little or nothing. Then they feel they need to defend their mistake for a while. They pretend they’re not suffering, until it breaks, then they go back to what they had in the first place, forever left with a bitter taste in their mouth about energy efficiency. Timers, low flow showerheads, tankless heaters. They’re all based on a mindset of “lack” rather than “abundance.” I’ve seen it first hand selling Solar Water Heaters. The miserly husband won’t admit he was wrong. Has all sorts of excuses. “I never run out of hot water.” “Cold showers are healthier.” While the wife is there staring holes in him. It’s my guess he’ll be taking alot of cold showers.

Response:

… But I’m convinced closed loop antifreeze is the way to go… The heat exchanger seems large and expensive and inefficient by comparison.

I needed a new tank anyway, to replace the one that failed due to the ravages of open loop operation. I could have spent three times as much for a pressure-capable stainless or stone-lined tank, trying to delay having to do this replacement again. Compared to the cost and hassle of swapping open-loop equipment, the extra cost of the exchanger tubing was trivial. It all fits in the same space as the old system, actually less than the drainback system used, and with only dead water in the tank, it should never again fail. If you go with the usual fancy pressurized tank with a single input exchanger, then yes, the cost is unreasonable. And it looks to me like even with stainless or stone tanks, you can count on a replacement in 15 years or less. Once you decide to keep the pressurized hot water in a separate exchanger coil, the cost of the tank drops way down, and the lifetime goes way up. I’ve ended up with a system I believe solves all these problems. There is a “primary loop” with antifreeze which runs through the input coils (five parallel 50′ coils of copper tubing) of my exchanger tank… That’s for solar charging, with hot antifreeze in the coils… …250′ of 1/2″ tubing would have about 33 ft^2 of surface and store about 3 gallons of water. I’d guess NTU = 30×33/(3×8x60) = 0.68, after the first 3 gallons, with E = 1-e^-NTU = 0.49… 50 F water in a 140 F tank might emerge from the coil at 50+0.49(140-50) = 94.5 F. You have another 250′ of tubing for heating pressurized cold water?

Yes. Actually the input tubing is 5/8″, to get the flow rate up on the Seahorse pump. The output tubing is 1/2″, matching your calcs. – Hide quoted text — Show quoted text – I really did try to make NTU work, even built an Excel sheet to automate it. But I ended up having to put in numbers like 90 for U (Cu is supposed to be 30) to get anywhere near the actual performance I observe. I can’t imagine what I’m doing wrong with the numbers or right with the hardware, but the real system works way better than I thought it would. I measured 30 for still water, but the cold water inside the tubing is flowing, which lowers the inside film conductance… One possibility I don’t think NTU accounts for is stratification – my domestic water enters at the bottom of the coils, and cools the bottom of the tank first. By the time it gets to the top end it needs very little more transfer to match the hot layer at the top of the tank. Counterflow is the right direction…

Interesting question, what is “counterflow” when there are two separated coils in dead water? My heat input flows downward from the top of the tank, the DHW output flows upward, maximizing the stratification. … I’ve been extremely pleased with the result. With a 3 GPM flow and 90F rise, the DHW comes out within a degree or two of the water in the top of the exchanger tank. Sounds lovely. Have you measured this after the first 3 gallons? Yes, and I don’t find any change at all between the first three and later gallons… Have you measured the antifreeze exit temp in the solar heating loop?

Depends on the usage history and the incoming sun, of course. At the moment (about noon) the nominal tank sensor (about 1/3 of the way up) is 127, the cold out is 112, and the return from the panels is 132. The tank target is currently 130F; extra heat goes into the hot tub, which is switched into the loop just ahead of the panels. Probably more useful is data from the gas heater – 50KBTU provides just about 20F rise across the 5/8″ input coils. Loren

Response:

I clicked on the free-survey information link on your site, but it only leads to a blank email. Are you selling something? no

Would you please explain what your survey is then. Wayne

Response:

… I wish! My water comes into my house at about 45 deg F. Last I looked there wasn’t an electric unit I could install that would increase the hot water to 105 for a shower. I’d love to be proven wrong on my last statement, if anyone has any info. Use two, one installed in series after the other. Each one only has to raise the temperature 30 degrees F. How much wattage do you figure that would consume?

Twice as much as one. Ok, some numbers off the top of my head. Let’s say you are taking a shower using 2 gal/minute. Your water is going from 45F to 105F or 60F. The water heater(s) need to raise the temperature of 120 gallons (8.34×120=1001 lbs) 60F per hour. One BTU raises one lb of water one deg F so this means we would need (1001×60=) 60060 BTU per hour or (60060/3415=) 17.6 kWh per hour. This amounts to 17.6 kW to run that heater or (17600/220=) 80 amps at 220V or 160 amps at 110V. This is rather much for a single circuit on most homes wiring so it might require two units at 40 amps each (8.8 kW) or three at 26.7 amps each (5.8 kW) on 220V lines. Most low flow showers seem to run about 1.8 to 2.4 gpm. There are some that do less than one gpm and the older showers seemed to average about 5 gpm. Anthony

Solar Panel Inverter batterey

Response:

I’m interested in experiences with various tankless/solar hot water systems. Ours just burned out (Myson tankless) after the vent was buried in snow.

Snow? You might want to consider how feasable a solar heater is in your area: http://www.homepower.com/education/solar_map.cfm

Response:

I’m interested in experiences with various tankless/solar hot water systems. Ours just burned out (Myson tankless) after the vent was buried in snow. I might try to fix it, but I’d like to know what the other experiences with Aquastar, Paloma, etc are. We are a family of 4 on propane with water efficient appliances planning to install solar DHW in the future, so this will revert to a backup some day. On the other hand, I might just go ahead an install a tank intended for solar hot water, so that we just hook up the panels and piping and we are done. Any experiences with either tankless or solar/propane hot water heaters? My wife likes hot water, so your timely response would be most appreciated! Will – Hide quoted text — Show quoted text – Can anyone tell me if they have had experience ( good or bad) with the 125 series AquaStar by Bosch tankless water heaters. They look real good on paper. Also does anyone know how they handle extremely hard water. Bosch say just remove exchanger, soak in vinegar, and re-install. Do this every couple of years. Solar Panel Inverter batterey

Response:

Obviously you have freezing temperatures to deal with. I struggled with each of the solar freeze protection systems in turn: The dribble valve wasted too much heat and too much water and eventually buried itself in ice anyway. To get the water up to the roof, the drainback system needed a big pump that was too noisy and too power hungry to run on PV. The draindown valve couldn’t handle my hard water and needed continuous attention… Sounds like you put in your struggling time. Did you consider letting the downgoing water help lift the upgoing water in a draindown system with a downpipe restriction that would put the solar collectors under a slight vacuum? Acorn solar houses worked this way.

I’m not sure what you are suggesting here. My draindown system (built by a local “professional”) was open-loop. When the “Sunspool” valve opened, the panels filled with no problem by the pressure of my domestic water system. The problem was with the valve itself and my hard water; it would stick, fail to close fully, and have to be disassembled, cleaned and lubed regularly. The tiniest bit of scale would keep the check ball from seating, and dump all the heat back out at night. And the connections to the heating element material for the “heat motor” in the valve kept failing. After replacing several actuators (at around $180 each), I finally developed a spring-loaded contact system to get power into the motor. Ugly, but it lasted for years. Solar Panel Inverter batterey

Category Categories: solar hot water heater | No Comments »

Newbie Ignorant Questions solar hot water heater orlando

Question:

I am more and solar hot water heater orlando more seriously considering adding some solar hot water to the house, and am not sure where to begin. I thought I’d ask some total newb questions here, and home for the best. I have a single story rancher that is an approx. 20×40 rectangle. The house faces due east. I don’t know what the exact pitch of the roof is, but I assume it would be fair to say, it is fairly “typical”. Not steep, but not flat. My first question then, could I mount panels on this roof (I am thinking the back side, west side for aesthetics) and have enough efficiency to get hot water? solar hot water heater orlando We currently have a 50 gallon hot water heater fired by gas. It is dieing and we planned on replacing it with an on-demand system, with no tank. My second question, could I add a solar hot water system to the on-demand and stay away from a tank? Or would it be best to have a tank? Are there sites that can answer these basic questions?solar hot water heater orlando

Response:

Hi, solar hot water heater orlando I am more and more seriously considering adding some solar hot water to the house, and am not sure where to begin. I thought I’d ask some total newb questions here, and home for the best. I have a single story rancher that is an approx. 20×40 rectangle. The house faces due east. I don’t know what the exact pitch of the roof is, but I assume it would be fair to say, it is fairly “typical”. Not steep, but not flat. My first question then, could I mount panels on this roof (I am thinking the back side, west side for aesthetics) solar hot water heater orlando and have enough efficiency to get hot water?

The solar water heater collector should be mounted facing south, and tilted up at approximately your local latitude. Variations of plus or minus 20 degs are OK — you will still get good performance. However, I do not think you will get good performance if you mount the panel facing West. A typical 3 in 12 or 4 in 12 pitch roof would only give you about 15 degs of tilt if you mounted the collector parallel to the roof surface. You could consider mounting the collector in the south yard (if it can see the south sky from this position). Or, you could mount it on the roof using a support system that allows the panel to face south. The collector should get 6 hours of good sun to work well. You can download a sunchart at:solar hot water heater orlando

Bosch AquaStar makes an on demand (tankless) heater that they recommed to use in solar water heating applications (it might the the model 125B). I’m not sure what the difference is, but its probably worth finding out. If you use a conventional solar water heating system with a tankless water heater, you will need a storage tank. If you use the “batch” (sometimes called ICS) style solar hot water heater (in which the tank and collector are combined in one unit), you won’t need a separate storage tank. The batch heaters are simple, and make a good DIY project, but are subject to freezing problems in colder climates. Are there sites that can answer these basic questions?

solar hot water heater orlando

Response:

the S series aquastars allow modulation of the gas valve, taking into consideration that the incoming water might be anywhere from 35F to 110F. solar hot water heater orlando

solar hot water heater orlandoI am more and more seriously considering adding some solar hot water to the house, and am not sure where to begin. I thought I’d ask some total newb questions here, and home for the best. I have a single story rancher that is an approx. 20×40 rectangle. The house faces due east. I don’t know what the exact pitch of the roof is, but I assume it would be fair to say, it is fairly “typical”. Not steep, but not flat. My first question then, could I mount panels on this roof (I am thinking the back side, west side for aesthetics) and have enough efficiency to get hot water? The solar water heater collector should be mounted facing south, and tilted up at approximately your local latitude. Variations of plus or minus 20 degs are OK — you will still get good performance. However, I do not think you will get good performance if you mount the panel facing West. A typical 3 in 12 or 4 in 12 pitch roof would only give you about 15 degs of tilt if you mounted the collector parallel to the roof surface. You could consider mounting the collector in the south yard (if it can see the south sky from this position). Or, you could mount it on the roof using a support system that allows the panel to face south. solar hot water heater orlando/SunChartProgram.html that will help you work out how much sun the collector will get in a given position. This is particularly important if there are trees or houses that might block the sun for part of the day. We currently have a 50 gallon hot water heater fired by gas. It is dieing and we planned on replacing it with an on-demand system, with no tank. My second question, could I add a solar hot water system to the on-demand and stay away from a tank? Or would it be best to have a tank? Bosch AquaStar makes an on demand (tankless) heater that they recommed to use in solar water heating applications (it might the the model 125B). I’m not sure what the difference is, but its probably worth finding out. If you use a conventional solar water heating system with a tankless water heater, you will need a storage tank. If you use the “batch” (sometimes called ICS) style solar hot water heater (in which the tank and collector are combined in one unit), you won’t need a separate storage tank. The batch heaters are simple, and make a good DIY project, but are subject to freezing problems in colder climates. Are there sites that can answer these basic questions? If you google “solar water heater” (or the like), quite a few come up. There is a recent book by Tom Lane that has an amazing amount of practical info on solar water heaters solar hot water heater orlando

Response:

<snip The solar water heater collector should be mounted facing south, and tilted up at approximately your local latitude. Variations of plus or minus 20 degs are OK — you will still get good performance. However, I do not think you will get good performance if you mount the panel facing West. A typical 3 in 12 or 4 in 12 pitch roof would only give you about 15 degs of tilt if you mounted the collector parallel to the roof surface. You could consider mounting the collector in the south yard (if it can see the south sky from this position). Or, you could mount it on the roof using a support system that allows the panel to face south.

Sorry, my bad…I thought I had implied that I would mount the units on some sort of rack to increase their angle towards the south. As my roof has a due east face and a due west face, I figured I’d have to raise one end of the panels up a bit to get better exposure. I didn’t make that clear. I can’t mount anywhere in the yard safely. Not with two boys and a neighborhood full of kids. LOL. The roof is my only option. The collector should get 6 hours of good sun to work well. You can download a sunchart at: http://solardat.uoregon.edu/SunChartProgram.html that will help you work out how much sun the collector will get in a given position. This is particularly important if there are trees or houses that might block the sun for part of the day.

Awesome site! Thanks! This leads me to another question. If I estimate very conservatively that with the panels on the west facing roof, I would get 5.5 hours of good sun, could I benefit from one panel on the east side, and one on the west? Both would get about 4-5 hours of really good direct sun, but at different times. Would the net effect be better then both on one face of the roof? Is that question clear? We currently have a 50 gallon hot water heater fired by gas. It is dieing and we planned on replacing it with an on-demand system, with no tank. My second question, could I add a solar hot water system to the on-demand and stay away from a tank? Or would it be best to have a tank? Bosch AquaStar makes an on demand (tankless) heater that they recommed to use in solar water heating applications (it might the the model 125B). I’m not sure what the difference is, but its probably worth finding out.

I have been looking at the Bosch systems. I am aware of those. If you use a conventional solar water heating system with a tankless water heater, you will need a storage tank. If you use the “batch” (sometimes called ICS) style solar hot water heater (in which the tank and collector are combined in one unit), you won’t need a separate storage tank. The batch heaters are simple, and make a good DIY project, but are subject to freezing problems in colder climates.

This is where my confusion gets worse. I am definately in a hard freeze area, so I will need a system whereby there is a heat exchange. So does that mean I have to have a tank? Or just a heat exchanger? Are there sites that can answer these basic questions? If you google “solar water heater” (or the like), quite a few come up. There is a recent book by Tom Lane that has an amazing amount of practical info on solar water heaters – “Solar Hot Water Systems — 1977 to Todaysolar hot water heater orlando

solar hot water heater orlando

Response:

the S series aquastars allow modulation of the gas valve, taking into consideration that the incoming water might be anywhere from 35F to 110F. solar hot water heater orlando

solar hot water heater orlando

Response:

Mount them both right on the south edge of the roof, they’ll be shaded less of the time. For that matter, you could also hang them from the south gable wall on angle brackets (better). Anyway, if the control system is set up to pump only the panel that’s got good sun when one does and the other does not, yes, this should work somewhat better. If (for simplicity and expense reasons) the pump is set up to pump both at the same time, having similar exposure for both panels (with appropriate storage) is better. This is where my confusion gets worse. I am definately in a hard freeze area, so I will need a system whereby there is a heat exchange. So does that mean I have to have a tank? Or just a heat exchanger?

You need a tank. You have to have someplace to store solar heated water, so that you can draw on the solar heated water (heated when the sun shines) to feed your tankless water heater (when you need hot water). A _large_ (80 or 120 gallon) electric water heater with extra insulation is probably the best bet (“solar storage tanks” are essentially the same thing without heating elements, but due to lower sales volume, they usually cost more – go figure…). You appear to have an aversion to tanks. This might be helped by locating a floor drain or pump to catch any disasters, perhaps with a tray under the water heater and a drain line running to the floor drain or sump. Actually doing a yearly or every 6 months flush on the tank might also help (install a better drain valve when the tank is new and you can still get the original crummy drain valve off). — Cats, Coffee, Chocolate…vices to live by

Response:

solar hot water heater orlando Awesome site! Thanks! This leads me to another question. If I estimate very conservatively that with the panels on the west facing roof, I would get 5.5 hours of good sun, could I benefit from one panel on the east side, and one on the west? Both would get about 4-5 hours of really good direct sun, but at different times. Would the net effect be better then both on one face of the roof? Is that question clear? Mount them both right on the south edge of the roof, they’ll be shaded less of the time. For that matter, you could also hang them from the south gable wall on angle brackets (better). Anyway, if the control system is set up to pump only the panel that’s got good sun when one does and the other does not, yes, this should work somewhat better. If (for simplicity and expense reasons) the pump is set up to pump both at the same time, having similar exposure for both panels (with appropriate storage) is better. This is where my confusion gets worse. I am definately in a hard freeze area, so I will need a system whereby there is a heat exchange. So does that mean I have to have a tank? Or just a heat exchanger? You need a tank. You have to have someplace to store solar heated water, so that you can draw on the solar heated water (heated when the sun shines) to feed your tankless water heater (when you need hot water). A _large_ (80 or 120 gallon) electric water heater with extra insulation is probably the best bet (“solar storage tanks” are essentially the same thing without heating elements, but due to lower sales volume, they usually cost more – go figure…). You appear to have an aversion to tanks. This might be helped by locating a floor drain or pump to catch any disasters, perhaps with a tray under the water heater and a drain line running to the floor drain or sump. Actually doing a yearly or every 6 months flush on the tank might also help (install a better drain valve when the tank is new and you can still get the original crummy drain valve off).

Aversion? LOL. No, well maybe a little. We currently have a 50 gallon behemoth, and most of the energy goes to heating and reheating because we don’t use it all. I hear that thing going on all night. It’s dieing so I planned on replacing the tank with a tankless on-demand system. I figured it would be more energy efficient, and we’d regain that last space which is currently at a premium. Then I got the idea for solar so I am trying to work an plan where I have solar and the on-demand combined. I am not adverse to a tank, but I’d like to minimize if possible. How small of a tank can I use?solar hot water heater orlando

Response:

How small of a tank can I use?

As small as you like – but small size limits the amount of good your solar system can do you, unless all your hot water use is at a slow rate and during days and times the sun is actually shining. For a given size collector, a small tank will overheat more quickly when no hot water is being used and the sun shines – and at that point your solar energy is being wasted, not stored for future use. The small tank will also run out faster when hot water is called for, so more gas will be used than would be the case with a larger storage tank, for the same hot water use. For electric heaters (which are simpler to insulate well due to the lack of a flue) there is very little difference in energy use for a properly insulated tank and a tankless heater if there is any hot water use going on – this was discussed either here or in alt.energy.homepower not that long ago, with actual measurements. With gas, the uninsulated (has to be, or the heat cannot get in from the flame) flue passage in the tank makes more of a difference between tank and tankless. Still, with proper tank insulation, you may be oversimplifing how much energy you waste on the tank, .vs. tankless, unless you use very little hot water indeed. Most of the energy goes to heating up cold water – less goes to losses from keeping heated water hot. With solar, the input energy is effectively free (not quite, there is some energy used to pump things) so heating up a tank (especially a very well insulated tank) costs very little, while not having enough storage means paying for gas to heat cold water when the preheated water runs out. Thus, bigger really is better; you’ll have to make the call about the space used .vs. the benefit derived. A 50 gallon water heater is hardly a behemoth. solar hot water heater orlando

Response:

- Hide quoted text — Show quoted text – How small of a tank can I use? As small as you like – but small size limits the amount of good your solar system can do you, unless all your hot water use is at a slow rate and during days and times the sun is actually shining. For a given size collector, a small tank will overheat more quickly when no hot water is being used and the sun shines – and at that point your solar energy is being wasted, not stored for future use. The small tank will also run out faster when hot water is called for, so more gas will be used than would be the case with a larger storage tank, for the same hot water use. For electric heaters (which are simpler to insulate well due to the lack of a flue) there is very little difference in energy use for a properly insulated tank and a tankless heater if there is any hot water use going on – this was discussed either here or in alt.energy.homepower not that long ago, with actual measurements. With gas, the uninsulated (has to be, or the heat cannot get in from the flame) flue passage in the tank makes more of a difference between tank and tankless. Still, with proper tank insulation, you may be oversimplifing how much energy you waste on the tank, .vs. tankless, unless you use very little hot water indeed. Most of the energy goes to heating up cold water – less goes to losses from keeping heated water hot. With solar, the input energy is effectively free (not quite, there is some energy used to pump things) so heating up a tank (especially a very well insulated tank) costs very little, while not having enough storage means paying for gas to heat cold water when the preheated water runs out. Thus, bigger really is better; you’ll have to make the call about the space used .vs. the benefit derived. A 50 gallon water heater is hardly a behemoth.

All good points. This makes me think that maybe I should replace my current tank system, with another tank and add the solar to it. Probably a better deal then adding a tankless on demand systems, and then retrofitting a tanked system to support the solar. Thanks for the post. As for the behemoth measurement…I guess it’s in the eye of a beholder eh? solar hot water heater orlando

Response:

The s series only adds the amount of heat needed to bring the water temp up to necessary. solar hot water heater orlando

solar hot water heater orlandothe S series aquastars allow modulation of the gas valve, taking into consideration that the incoming water might be anywhere from 35F to 110F.solar hot water heater orlando

With Solar, you need a tank. That tank might be inside of the collector up on the roof, in a passive thermosyphon or batch type collector, or in the house where your present standard tank is, with an active system. Either way it needs to be big unless you are in a climate that has sunshine every day. Tanks of 80 gallons or more are standard. Instead of screwing up the looks of your house, and lowering its resale value, with an unprofessional tacky collector installation up on racks above your roof, have your collectors mounted flush to your west or east roof. The efficiency will be lower, than on a southern exposure, so you will need to compensate by increasing your collector area by 50-100%, depending on your latitude, how far they are aimed from south, and the pitch of the east/west roof where you mount the system. But, you will also not have the costs involved in a complicated tilt rack mounting. That will give you a much more professional installation, that will look like skylights, not an ugly piece of machinery. In most cases the end cost of extra collector, instead of extra tilt racks and labor, is close. I worked with a company that installed thousands of hot water systems. That was the best way for a house without an optimum south facing roof. Tilt racks on weird angles are really tacky. Most people who make that mistake, end up paying to have the collector system taken down, especially when they want to sell the house for top dollar. -Laren Corie-

Response:

<snip With Solar, you need a tank. That tank might be inside of the collector up on the roof, in a passive thermosyphon or batch type collector, or in the house where your present standard tank is, with an active system. Either way it needs to be big unless you are in a climate that has sunshine every day. Tanks of 80 gallons or more are standard.

I am hoping to replace my current 50 gallon gas fired unit, but feed it with solar, so I use less gas. I don’t have room for an 80 or up. – Hide quoted text — Show quoted text – Instead of screwing up the looks of your house, and lowering its resale value, with an unprofessional tacky collector installation up on racks above your roof, have your collectors mounted flush to your west or east roof. The efficiency will be lower, than on a southern exposure, so you will need to compensate by increasing your collector area by 50-100%, depending on your latitude, how far they are aimed from south, and the pitch of the east/west roof where you mount the system. But, you will also not have the costs involved in a complicated tilt rack mounting. That will give you a much more professional installation, that will look like skylights, not an ugly piece of machinery. In most cases the end cost of extra collector, instead of extra tilt racks and labor, is close. I worked with a company that installed thousands of hot water systems. That was the best way for a house without an optimum south facing roof. Tilt racks on weird angles are really tacky. Most people who make that mistake, end up paying to have the collector system taken down, especially when they want to sell the house for top dollar.

That’s a good piece of advice, and I intend to follow it. If the array looks like hell, my wife will kill me. — BV. www.iheartmypond.com

Response:

solar hot water heater orlando <snip With Solar, you need a tank. That tank might be inside of the collector up on the roof, in a passive thermosyphon or batch type collector, or in the house where your present standard tank is, with an active system. Either way it needs to be big unless you are in a climate that has sunshine every day. Tanks of 80 gallons or more are standard. I am hoping to replace my current 50 gallon gas fired unit, but feed it with solar, so I use less gas. I don’t have room for an 80 or up. Instead of screwing up the looks of your house, and lowering its resale value, with an unprofessional tacky collector installation up on racks above your roof, have your collectors mounted flush to your west or east roof. The efficiency will be lower, than on a southern exposure, so you will need to compensate by increasing your collector area by 50-100%, depending on your latitude, how far they are aimed from south, and the pitch of the east/west roof where you mount the system. But, you will also not have the costs involved in a complicated tilt rack mounting. That will give you a much more professional installation, that will look like skylights, not an ugly piece of machinery. In most cases the end cost of extra collector, instead of extra tilt racks and labor, is close. I worked with a company that installed thousands of hot water systems. That was the best way for a house without an optimum south facing roof. Tilt racks on weird angles are really tacky. Most people who make that mistake, end up paying to have the collector system taken down, especially when they want to sell the house for top dollar. That’s a good piece of advice, and I intend to follow it. If the array looks like hell, my wife will kill me. — BV. www.iheartmypond.com

Hi, I think that this is basically good advice, but with your fairly low pitch roof, and your fairly high latitude, you should be aware that you will not get much sun on the collector panel during the mid winter months. The sun just does not get high enough in the winter to put a lot of useful sun on a panel with low tilt. The table below compares the daily total solar radiation received by 1 square foot of panel for a horizontal panel to a panel tilted at an angle equal to latitude and aimed south (the ideal case) — this is for a latitude of 48degrees (Northern US). These numbers are for sunny days. Horizontal Tilted 48 deg to South Jan 596 1478 BTU/ft^2-day Feb 1080 1972 Mar 1578 2228 Apr 2106 2266 May 2482 2234 Jun 2626 2204 Jul 2474 2200 Aug 2086 2200 Sep 1522 2118 Oct 1022 1860 Nov 596 1448 Dec 446 1250 So, the horz panel does fine in the summer, but is not so good in the 3 or 4 months of winter. As suggested, you could increase the panel area to partially offset this. Good Luck — Gary

Response:

When the sun is in the west, it’s usually warmer. For all that means. In your area (you don’t say) that might mean it clouds up. I get fog around 4-5PM everyday. This is where my confusion gets worse. I am definately in a hard freeze area, so I will need a system whereby there is a heat exchange. So does that mean I have to have a tank? Or just a heat exchanger?

What area? Got a state? Oregon hard freezes, but not like Michigan. Is it possible to just run empty in the winter with these (turn it off) and use it when the water isn’t going to freeze and screw the heat exchange? It’s not quite AS effective, but for 7-8 months/year it means you don’t need anti-freeze and a big tank. You need a tank. You have to have someplace to store solar heated water, so that you can draw on the solar heated water (heated when the sun shines) to feed your tankless water heater (when you need hot water). A _large_ (80 or 120 gallon) electric water heater with extra insulation is probably the best bet (“solar storage tanks” are essentially the same thing without heating elements, but due to lower sales volume, they usually cost more – go figure…).

Well, some tank to do heat exchange. In my non-hard freeze area (or rare), I can get away with a 10-20 gallon tank in front of a tankless heater. Showers will likely not use more than that. If something does, then I’m in a “no solar” state and the tankless heater just does what it does. I just picked up a bunch of info at a Green Fair in Berkeley today (small, in a small park). Was looking at a Japanese tankless (50 years in .ja and 10 years in the US) on display. It heats the water UNTIL it reaches the set point (110, 115). Tomorrow AM, I meet with a solar contractor. He had an issue with a client who was storing water that was TOO hot. Water sits around and recircs and heats and recircs and heats and comes out at Tea making temps. I think the solution was just a bigger (25gal) storage tank). You appear to have an aversion to tanks. This might be helped by locating a floor drain or pump to catch any disasters, perhaps with a tray under the water heater and a drain line running to the floor drain or sump. Actually doing a yearly or every 6 months flush on the tank might also help (install a better drain valve when the tank is new and you can still get the original crummy drain valve off).

I’d suggest that it’s size. solar hot water heater orlando I have room for either my 50 gal tank or a tankless with a little bitty solar tank (eg, 100 gallons? Perhaps in the guestroom).

Response:

Category Categories: solar hot water heater | No Comments »

build solar hot water heater System On New House?acuum solar hot water heater

Question:

We are getting ready to build a house and build solar hot water heater are interesting in installing a solar PV system. Through the state and our power company we can get a rebate of about 45% on a PV system which makes the price only moderately shocking (no pun intended). You have to be on the grid to get the rebate and the power company gets to keep any extra electricity you generate. We would like to build the house to run on electricity only. In our existing house we are using an average of 1,000kWh per month. The new house will be bigger and and we will be cooking and heating the house and water using electricity instead of gas, so I know we will be using more than we are now. It seems to me we could guesstimate what we need in a new system (1,500 kWh as a start?) and add additional panels if needed. My questions (finally): 1. Is it easy to add panels to a PV system? 2. For heating water should we consider an on-demand heater like this: http://www.tankless-water-heater.com/ or should we go with an electric tank style water heater, build solar hot water heater or should we consider a solar water heating system, or a combination of the above (What happens when you run out of water with a solar water heating system. Is some sort of backup usually installed)? 3. Is running a house from a PV system even feasible? 4. Are there any websites/books/etc that you would recommend? We re building in inland Southern California and get lots of sunshine.

Response:

First of all, don’t heat your water build solar hot water heater with PV. acuum solar hot water heater
Heat your water with solar thermal and/or gas. Solar thermal is four times as efficient as PV for heating water.

Response:

… We are getting ready to build a house and are interesting in installing a solar PV system.

A good time to do so. Building build solar hot water heater integrated systems can cost less than stuff added on later. Look at solar PV shingles, standing seam roof panels or other similar products. Using these on your roof you get to kill two birds with one stone. You can also design your roof and the shape of your house to optimize the solar production. Lastly, the cost of the works can be rolled into the total cost of your home and simply becomes part of your mortgage. We would like to build the house to run on electricity only.

Look really hard at this one. It can take a lot of electricity to heat water, cook food and keep the house warm. It would be cheaper, compared to the price of grid electricity, to heat and cook using something else. Since solar PV is more expensive than grid power, even with the buydowns or rebates, it’s cheaper to conserve electricity. That is, not use it in the first place. Look at gas, propane, wood pellet stoves & furnaces, corn burning stoves & furnaces, solar heating, solar cooking and the like. Some random links from googleacuum solar hot water heater

Look at solar PV shingles

That is all you should do with solar PV shingles, look at them.

acuum solar hot water heater

Response:

The words “thin film” bother me a bit. In one of the pictures it build solar hot water heater kind of looks like a tarp was laid on the roof. Is that how you install this stuff? How durable is it?

Response:

The words “thin film” shouldn’t bother you any more than “crystalline”, “glass” or “electricity”. build solar hot water heater. These unisolar products are amorphous panels. They don’t use glass so they aren’t quite as fragile as other panels. They also produce a little better when hot than other types of panels but their efficiency is half that of crystalline PV. That means you’ll need twice the area for them to produce an equal amount of power. In one of the pictures it kind of looks like a tarp was laid on the roof.

This is only because the roof shingles were a different color from the PV shingles. You would get a similar effect using any two color scheme on your roofing shingles. They are not a tarp. If you chose a roof shingle with a similar color they would blend in very well. Personally, I prefer the structural standing seam roofing panels over the shingles. Is that how you install this stuff?

Installation instructions are on the website. They install in a manner similar to other roofing shingles (nailed in place using roofing nails over felt) except that they are little over 7 feet long and you need to drill a small hole through the deck for each one to feed the wires through for the electrical connection. How durable is it?

They come with a 20 year warranty and are made from steel and plastic. How durable do they need to be? They will certainly outlast a roof made from asphalt and paper.

Response:

I think you will find the roof build solar hot water heater panels more cost effective than the shingles, if you are starting with a new roof. They are all durable, but you have to come up with the cost justification.

Response:

I think you will find the roof panels build solar hot water heater more cost effective than the shingles…

They don’t seem that expensive, at $384 ($6/W) for the SSR-64 from solarwares.com, $5.88/W from aapspower.com, and $5.54/W from solarwindworks.com… Anyone know of better prices for the PVL-64 and -128 “field-applied roofing laminates” which come in 9′ and 18′ rolls? Unisolar’s engineering manager says he doesn’t see a guarantee problem with trickling hot water over their faces, under a layer of polycarbonate.

Response:

Be sure to compare the installed build solar hot water heater price, unless you plan to do the work yourself. My understanding is that the solar shingles are a lot more work to install than panels.

acuum solar hot water heater

We would like to build the house to run on electricity only.

It’s more difficult, but we did it that way. Details at www.ctaz.com/~wmbjk In our existing house we are using an average of 1,000kWh per month. The new house will be bigger and and we will be cooking and heating the house and water using electricity instead of gas, so I know we will be using more than we are now. It seems to me we could guesstimate what we need in a new system (1,500 kWh as a start?) and add additional panels if needed.

If you start from scratch, you should be able to have the same conveniences on less energy. You’ll pay extra for some of the appliances, and more care will be required in how they’re used. My questions (finally): 1. Is it easy to add panels to a PV system?

Adding additional panels isn’t a problem, especially if you allow for it in advance. 2. For heating water should we consider an on-demand heater like this:acuum solar hot water heater

We don’t have a backup. There are several days a year when we have barely warm water. It’s a PITA, but not what I’d call a hardship. I just spent the money we could have used for a tankless backup on a plasma cutter instead. On the lukewarm-water days, I’ll go out and admire the plasma cutter. :-) YMMV 3. Is running a house from a PV system even feasible?

Absolutely. 4. Are there any websites/books/etc that you would recommend?

Start with Home Power magazine. The current issue, and many excellent articles from previous issues, are available online for free. Wayne

Response:

2. For heating water should we consider an on-demand heater like this: http://www.tankless-water-heater.com/ or should we go with an electric tank style water heater, or should we consider a solar water heating system, or a combination of the above Up-front cost will be higher, but a solar water-heating system with a tankless backup would be ideal.

Keep in mind that where electric heating is involved, you can’t get around the fact that you pay for what you use. All a tankless/ondemand heater will save you over a electric tank storage system with an electrical backup, is the heat loss that would occur though the tank itself. Which is minimal on a high quality tank, especially if you wrap an additional layer of insulation around it. BTW, I should introduce myself. I’m Stephen, I’m a Solar Contractor and have been into Solar since 1979 (the good ‘ol tax credit days). For the past few years I’ve been concentrating on Real Estate; I’m also a Real Estate Agent. But I can’t let go of this Solar thing! It’s like an addiction.acuum solar hot water heater

Oh boy. I knew as soon as you said “cook and heat with electricity” you’d get jumped on. I’m with you, why mess with non-renewable resources like gas when the sun provides tons of energy for free? Unfortunately, my investigations have also shown that the traditional solar cells — battery storage — appliances as needed doesn’t work well for high-wattage items like an electric stove or heater; even if you put the money into buying enough panels and batteries to have enough power, the drawdown is so big when they are used that you’ll need to replace those expensive batteries practically every week. (Okay, I’m exaggerating a LITTLE …) If you’re planning to stay on-grid, not mess with batteries, and just use the solar array to reduce your electric bills, it won’t matter. But if you’re hoping this will keep you in reliable power during brownouts and blackouts, you can either just decide to turn off the electric water heater and not use the electric stove when the grid is down, or read on for our plans. ;) Our land in the country, where we are not living now but hope to RSN, has very reliable grid service. However, being 15 miles out of town, I’m assuming if it ever fails it will be under the worst possible conditions, such as a blizzard or ice storm that would keep us from being able to get into town. Reliable backup power could literally mean the difference between life and death in that case. In addition, DH and I are both emotionally committed to replace our use of non-renewable resources with renewables as quickly and completely as possible, so we don’t want to build in anything using LP or petroleum products. My original thought was to use a wind generator to power the high-demand appliances. I’ve been told that won’t work well because you can’t channel the wind-produced AC right into a house AC system. I still don’t understand why but since EVERYONE knowledgable has given me the same answer, I have to assume they are probably right. So our current plans, when we build, are to use everything renewable we can — belt and suspenders, so to speak. Big south-facing windows and lots of thermal mass to minimize heating needs. (Believe it or not, we get so much sun here in windy Wyoming that the plants in my big south-facing living room window do fine all winter, even when it’s 20 below outside!) Some kind of heating stove that will burn renewables: haven’t decided between wood (scarce around here) or corn or #2 heating oil (which is interchangeable with diesel, more on that later). A fan system to move the warm air from the heating stove around the house. Some kind of water reservoir in or around the heater with a tankless electric heater near where hot water is needed. Lots of cooking alternatives, including my crockpot, microwave, steamer, and a solar oven built into the south wall, besides the electric stove. And a diesel generator to supply the high-wattage power needed for electric stove and water heater. Why diesel and #2 home heating oil, when I made it clear we didn’t want to be dependent on ANY non-renewable energy sources? Because biodiesel can be substituted for either regular diesel or #2 oil. Biodiesel sounds absolutely wonderful and feasible for us to make on our own; we’re currently hunting for a super-cheap old diesel vehicle so we can see if we can make our own fuel before spending big bucks on a newer diesel to be our main car. Assuming we are able to establish a regular source of waste vegetable oil (WVO), process it into biodiesel ourselves, and store it safely until needed, we should be able to meet our housing and mobility needs with no use of nonrenewable resources! Wheeeee! — Sylvia Steiger RN BS http://www.SteigerFamily.com Cheyenne WY, USDA zone 5a, Sunset zone 1a Home of the Wyoming Wind Festival, January 1-December 31

Response:

Energy from the sun may be free but the hardware to capture it, convert it, store it and so forth sure aren’t. :) But that is your call. Unfortunately, my investigations have also shown that the traditional solar cells — battery storage — appliances as needed doesn’t work well for high-wattage items like an electric stove or heater; even if you put the money into buying enough panels and batteries to have enough power, the drawdown is so big when they are used that you’ll need to replace those expensive batteries practically every week. (Okay, I’m exaggerating a LITTLE …)

Uhmmmmm,,, no, a person just needs to properly size the number of panels/batteries/inverters/wiring and so forth to match the load, even if it is a high wattage load(s). Conclusion: with the proper sized panels/batteries and so forth, a person could run *all* the high-wattage appliances they want. Just takes money. Lots of money. If you’re planning to stay on-grid, not mess with batteries, and just use the solar array to reduce your electric bills, it won’t matter. But if you’re hoping this will keep you in reliable power during brownouts and blackouts, you can either just decide to turn off the electric water heater and not use the electric stove when the grid is down, or read on for our plans. ;) Our land in the country, where we are not living now but hope to RSN, has very reliable grid service. However, being 15 miles out of town, I’m assuming if it ever fails it will be under the worst possible conditions, such as a blizzard or ice storm that would keep us from being able to get into town. Reliable backup power could literally mean the difference between life and death in that case.

You could simplify your plan by just having a backup wood stove to provide heat and a coleman type camp stove/lantern and a few cans of beans when it is storming outside and grid power is interupted. This setup is a tried and true method that has been used by lots of settlers before you in Wyoming/Montana and elsewere while raging blizzards and sub-sub zero temperatures are occuring outside. So how long does grid power go out where you propose to live and for how long? :) In addition, DH and I are both emotionally committed to replace our use of non-renewable resources with renewables as quickly and completely as possible, so we don’t want to build in anything using LP or petroleum products. My original thought was to use a wind generator to power the high-demand appliances. I’ve been told that won’t work well because you can’t channel the wind-produced AC right into a house AC system. I still don’t understand why but since EVERYONE knowledgable has given me the same answer, I have to assume they are probably right.

You would have to channel the DC power from the windmill to your batteries, then through the inverter and then into your AC appliances. So our current plans, when we build, are to use everything renewable we can — belt and suspenders, so to speak. Big south-facing windows and lots of thermal mass to minimize heating needs. (Believe it or not, we get so much sun here in windy Wyoming that the plants in my big south-facing living room window do fine all winter, even when it’s 20 below outside!)

Of course your plants do well, it is 70 degrees inside the house and they get all the sunlight they want Some kind of heating stove that will burn renewables: haven’t decided between wood (scarce around here) or corn or #2 heating oil (which is interchangeable with diesel, more on that later).

Corn is scarce too in Wy, but easy enough to get in Northern Colorado, which isn’t to far away from Cheyenne. How many miles would it be to truck some in? A fan system to move the warm air from the heating stove around the house. Some kind of water reservoir in or around the heater with a tankless electric heater near where hot water is needed. Lots of cooking alternatives, including my crockpot, microwave, steamer, and a solar oven built into the south wall, besides the electric stove. And a diesel generator to supply the high-wattage power needed for electric stove and water heater.

Good plan. Have you given it any thought on how to keep your diesel/bio-diesel from jellying in the tank(s) when it gets below zero? As in 0, -20,-30,-50 degrees F? Which occurs a number of times each winter? I understand bio-diesel is really touchy in cold temperatures. Why diesel and #2 home heating oil, when I made it clear we didn’t want to be dependent on ANY non-renewable energy sources? Because biodiesel can be substituted for either regular diesel or #2 oil. Biodiesel sounds absolutely wonderful and feasible for us to make on our own; we’re currently hunting for a super-cheap old diesel vehicle so we can see if we can make our own fuel before spending big bucks on a newer diesel to be our main car. Assuming we are able to establish a regular source of waste vegetable oil (WVO), process it into biodiesel ourselves, and store it safely until needed, we should be able to meet our housing and mobility needs with no use of nonrenewable resources!

Then you will need a truck of some sort to haul all the barrels that will contain the used cooking frier oils from fast food/restraunts back to your homestead for processing. You mentioned possible getting a diesel powered “car”. Perhaps you may want to think diesel powered PU. Kill two birds with one stone. BTW, have you ever tried starting a diesel engine when it has been sitting out in temperatures overnight of minus 10 F (or lower) ? Ugly, You will be also competing with whomever else has the same ideas as you about making less expensive biodiesel. As far as storing it *safely*? Hope you store it far away from the main living quarters because it is very flammable. Just like storing barrels of gasoline next to your house. Once the fuel source gets ignited (by whatever means) , it then becomes a potential powder keg. Then you have the smell, fumes, spillage and contamination from handling it to content with. But it is free. Wheeeee!

Wheee is right! Can be fun and entertaining. Good luck

Response:

…my investigations have also shown that the traditional solar cells — battery storage — appliances as needed doesn’t work well for high-wattage items like an electric stove or heater; even if you put the money into buying enough panels and batteries to have enough power, the drawdown is so big when they are used that you’ll need to replace those expensive batteries practically every week. (Okay, I’m exaggerating a LITTLE …)

Trojan batteries are rated for total “lifetime energy storage.” They wear out after say, 1000 100% charge-discharge cycles or 2000 50% cycles, and so on, approximately. They actually store more lifetime energy with fewer and deeper discharges, eg 30% vs 5%, and they have a finite shelf life, even if never discharged. You need more batteries to store the same amount of energy with shallower discharges, and batteries take up space and up-front and ongoing money. Most PV people tend to overpopulate and underdischarge batteries in an uneconomical way. Our land in the country, where we are not living now but hope to RSN, has very reliable grid service. However, being 15 miles out of town, I’m assuming if it ever fails it will be under the worst possible conditions, such as a blizzard or ice storm that would keep us from being able to get into town. Reliable backup power could literally mean the difference between life and death in that case.

You might have just a few batteries, say enough for 12 hours for critical loads, and a generator to charge them or operate critical loads by itself if needed. That gives triple redundancy: grid, batteries, and generator. My original thought was to use a wind generator to power the high-demand appliances. I’ve been told that won’t work well because you can’t channel the wind-produced AC right into a house AC system. I still don’t understand why but since EVERYONE knowledgable has given me the same answer, I have to assume they are probably right.

I wouldn’t write off wind power quickly, if you have wind. It’s cheaper than PV, closer to $1 than $5 per peak watt, especially with a tree or a barn for a tower, and it can work on cloudy days or at night. It does require more maintenance than PVs. You might either get a small DC turbine and use an inverter, or get a larger one with an AC induction motor which can match grid power if present and match your inverter if not. Or maybe make “wild AC” and rectify that to make DC. This can be more efficient than a 60 Hz system, with a varying vs fixed prop speed. So our current plans, when we build, are to use everything renewable we can — belt and suspenders, so to speak. Big south-facing windows and lots of thermal mass to minimize heating needs.

I’d suggest “lots of insulation,” eg a house built with Structural Insulated Panels (SIPs), ie glued plywood-foamboard-plywood sandwiches. Water can be excellent thermal mass, cheaper and more compact than masonry, storing 3X more heat by volume, easy to insulate and move around, fairly easy to heat with the sun. Big south windows can lose lots of heat at night and on cloudy days. Part of the south wall could be simple thermosyphoning air heaters which lose no heat at night, or you might supply daytime heat for the house from a low-thermal-mass sunspace. You might have a hydronic slab and trickle warm water between a dark metal roof and a single layer of polycarbonate greenhouse roofing (eg “Dynaglas”) over that, with a higher temp heat store for cloudy days. Part of the metal roof might be covered with Unisolar PV “field-applied roofing laminate,” with water trickling over that. And a diesel generator to supply the high-wattage power needed for electric stove and water heater.

Start the diesel whenever you want to make a cup of tea? You might heat water or the house with its “waste heat,” which might be 80% of the fuel’s heating value… …Biodiesel sounds absolutely wonderful and feasible for us to make on our own… Assuming we are able to establish a regular source of waste vegetable oil (WVO), process it into biodiesel ourselves, and store it safely until needed, we should be able to meet our housing and mobility needs with no use of nonrenewable resources!

Sounds like more ongoing work than sun and wind power. And less independent, with this “regular source” requirement. And you will be adding CO2 to the atmosphere. Nick

Response:

My original thought was to use a wind generator to power the high-demand appliances. I’ve been told that won’t work well because you can’t channel the wind-produced AC right into a house AC system. I still don’t understand why but since EVERYONE knowledgable has given me the same answer, I have to assume they are probably right.

Don’t understand this. If you’re on grid, you can take advantage of Wyomings’ net metering law, which even calls for utility purchase of annual excess wind energy at avoided cost. Off-grid, you would depend on batteries. As others point out, your occasional off-grid dependence on (wind and) batteries and their 1000 or so discharge cycles for your “high-demand applicances” (the use of which would be curtailed during an emergency, one would think), would not guarantee a weekly battery replacement, or even yearly. Maybe 5-yearly to 8-yearly, depending on what you buy and how you maintain it. You need a 48-V DC 7.5 kW wind turbine/controller (Bergey), 18 grand, a pair of Xantrex SW 4-kW inverters (with GTI), 6 grand, a 7.5 kW dump load (heater/water heater) for dumping excess energy during off-grid operation, ? grand, and between 100 and 750 Ah (at 48 VDC) of batteries, 1 grand to 6 grand, depending on how often and how long you expect to put up with grid outages. If your annual average wind speed is 12 mph or higher, you can expect that turbine to produce 15,000 kWh annually, or more. The purchase of annual excess energy guranteed by Wyoming’s excellent net metering law makes this system more attractive to people in your situation than in most of the other net metering states, where excess energy is donated to the utility.

Response:

You need a 48-V DC 7.5 kW wind turbine/controller (Bergey), 18 grand, a pair of Xantrex SW 4-kW inverters (with GTI), 6 grand, a 7.5 kW dump load…

I still don’t get it. Why do wind turbines need dump loads? Why not just operate them closer to stall speed? Nick

Response:

You need a 48-V DC 7.5 kW wind turbine/controller (Bergey), 18 grand, a pair of Xantrex SW 4-kW inverters (with GTI), 6 grand, a 7.5 kW dump load (heater/water heater) for dumping excess energy during off-grid operation, ? grand, and between 100 and 750 Ah (at 48 VDC) of batteries, 1 grand to 6 grand, depending on how often and how long you expect to put up with grid outages.

Although using excess energy build solar hot water heater during off-grid operation is not a bad thing, with the setup you describe there is no requirement for a dump load. The Bergey is designed to run unloaded. — ron (off the grid in Downeast Maine)

Response:

Although using excess energy during off-grid operation is not a bad thing, with the setup you describe there is no requirement for a dump load. The Bergey is designed to run unloaded.

Response:

Why does any wind turbine need a diversion load, with an MPPT that can load it to limit power?

Response:

Why does any wind turbine need a diversion load, with an MPPT that can load it to limit power?

build solar hot water heater, I don’t understand much about MPPT — how does it work with a wind turbine, and how would that obviate the need for a dump load (for those turbines that require one).

Response:

Conclusion: with the proper sized panels/batteries and so forth, a person could run *all* the high-wattage appliances they want. Just takes money. Lots of money.

I guess I should have specified that it wasn’t a realistic option unless they have more money to throw at it than I do! You could simplify your plan by just having a backup wood stove

No readily-available wood unless we buy it and keep it on hand. Whereas I hope we WILL have biodiesel stored on-site to run an oil heater. So how long does grid power go out where you propose to live and for how long? :)

As I said, I don’t know that it has build solar hot water heater. I’m just planning for a worst-case emergency. Of course your plants do well, it is 70 degrees inside the house and they get all the sunlight they want

Do you do much gardening? The participants on the gardening newsgroups frequently discuss the need for additional light for indoor plants during the winter because they suffer during short, cloudy days. Since they agree my high amount of sunlight is exceptional, your comment seems rather ignorant. Good plan. Have you given it any thought on how to keep your diesel/bio-diesel from jellying in the tank(s) when it gets below zero?

Of course. That is a problem we’ll have to face for vehicles as well. We haven’t decided on a system yet but it will be included. I understand bio-diesel is really touchy in cold temperatures.

My research is that it isn’t any less likely to jell than petrodiesel … but it isn’t any less likely, either. :( Then you will need a truck of some sort

Not just for hauling WVO! Believe me, I already wish we had a pickup. But my immediate priority is anything diesel and cheap; no point in spending the bucks for a nice diesel PU if it turns out we can’t manage to make our own biodiesel. Hope you store it far away from the main living quarters because it is very flammable. Just like storing barrels of gasoline next to your house.

Have you ever actually looked into this? Diesel is NOT as flammable as gasoline. Sure it needs to be stored appropriately, and not in a living room, but hundreds of thousands of people are managing to do so, and I’m confident we can also.

Response:

I don’t understand much about MPPT — how does it work with a wind turbine,

You can think of it as “impedance matching for maximum power transfer.” If you push on a boxcar, it won’t move, with no useful human power output: a large force times zero velocity equals zero power. If you push on a feather, you and it will move so easily that there won’t be any useful human power either, with a large velocity but close to zero force. You can maximize your useful power output by pushing on something between, eg a car, if you feel strong, or a wheelbarrow or wagon, if you are tired. Here’s a wind interpretation: connect a large load (a small resistor) to a wind generator, and the blades won’t turn much. They will be aerodynamically stalled, and the generator won’t produce build solar hot water heater much electrical power. Connect a small load (a large resistor) and the blades spin fast and the generator produces a large voltage but little current, with little useful power. and how would that obviate the need for a dump load (for those turbines that require one).

As windspeeds increase, increase the load on the generator to limit the rpm and power output to some maximum value, ie make the wind turbine operate less efficiently. This isn’t MPPT, but it can be done with the same hardware…

Response:

Conclusion: with the proper sized panels/batteries and so forth, a person could run *all* the high-wattage appliances they want. Just takes money. Lots of money. I guess I should have specified that it wasn’t a realistic option unless they have more money to throw at it than I do!

I know. It is rather difficult to respond to some of these financial issues because one doesn’t know the persons porfolio. After I punched the send key on the last message, I thought that wouldn’t it be funny if you were a Bill Gates clone and what I said wouldn’t have mattered because a Bill Gates clone could afford any kind of PV system he wanted to power whatever high wattage load he wanted with just his pocket change. :) You could simplify your plan by just having a backup wood stove No readily-available wood unless we buy it and keep it on hand. Whereas I hope we WILL have biodiesel stored on-site to run an oil heater.

In a *strict* emergency only build solar hot water heater situation , a free standing, non nonsense, no electric fan driven wood stove would be ideal. Buy a cord of wood and have it sitting on standby. Most economical scenario for emergency heating. Which was the thought? All the oil burner heating stoves that I know of require electricity to operate the pump, fan, thermostat and such. Now if you are talking a diesel/gas powered generator in conjunction with the oil burner, then that’s a doable combination. Considered a pellet stove? You could haul the commercial processed pellets from WalMart in the back of your future PU. – Hide quoted text — Show quoted text – So how long does grid power go out where you propose to live and for how long? :) As I said, I don’t know that it has. I’m just planning for a worst-case emergency. Of course your plants do well, it is 70 degrees inside the house and they get all the sunlight they want Do you do much gardening? The participants on the gardening newsgroups frequently discuss the need for additional light for indoor plants during the winter because they suffer during short, cloudy days. Since they agree my high amount of sunlight is exceptional, your comment seems rather ignorant.

You didn’t specify what kind of plants. We have plants, people in the drizzly rainforest of western Oregon (cloud free days in the winter are a rarity) had/have house plants, everyone I know of have some sort of house plants and no one that I know of has supplementary artificial lights. Wyoming has plenty of cloud free days. Different variety of house plants need different amounts of lights ( to the point of too much sunlight is detrimental to its survival) and whatever variety I’ve seen must not have been to picky. In conclusion, whatever variety you are interested in must need more light. Do you garden by committee since you base your gardening knowledge from what newsgroups say? Or are we discussing eatable vegetable type plants that you choose to grow indoors? Good plan. Have you given it any thought on how to keep your diesel/bio-diesel from jellying in the tank(s) when it gets below zero? Of course. That is a problem we’ll have to face for vehicles as well. We haven’t decided on a system yet but it will be included.

What system? Either you run a winter blend (petroleum based diesel) or you don’t(vehicle application here) . You can add an anti-jellying additive to #2Diesel that gets you down to ~-10F before jellying. When you are talking real cold, then straight #1 is the ticket. Then you need to figure out how to even crank over the diesel motor when it has been sitting out in subzero temperatures for the afternoon/night with 15w-40 motor oil in the crankcase and it acts like 120w. Electric engine block heaters, battery warmers and such that draw 1500watts plus are the common solution. Good idea to plug in your car for numerous hours before needing to start it. Good idea even for gas burners when temperatures get that low. We are talking the extreme emergency situation still aren’t we? You will see these conditions several times a winter. I know, I have lived in Wyoming before. Great state, great bunch of people. Got your Carhartt polar insulated coveralls and Pak Boots purchased? :) I understand bio-diesel is really touchy in cold temperatures. My research is that it isn’t any less likely to jell than petrodiesel …

but it isn’t any less likely, either. Don’t know for sure about bio-diesels cold temperature characteristics. Hate build solar hot water heater to bet my life on it but it may be the cats meow. Then you will need a truck of some sort Not just for hauling WVO! Believe me, I already wish we had a pickup. But my immediate priority is anything diesel and cheap; no point in spending the bucks for a nice diesel PU if it turns out we can’t manage to make our own biodiesel.

PU is still real handy when you have to haul building materials to the homestead. Hay for the future pony. Makes sense to get a diesel for the fuel economy, less pollution (than gas) and so forth, even if you end up not burning bio-diesel in it. 4×4 PU’s are real handy to bust through the snow drifts going home, where a car would get stuck. Did I mention I can tell you are not a native of Wyoming. <g PU’s rule in Wyoming (cowboy Cadillac) and the preferred mode of transportation (by natives) . Gotta get the big Wyoming mud flaps too. <g Don’t forget to get the big honken oil field special grill guard to protect yourself from suicidal antelope/deer/out_of_state_compact_cars. Careful about the “anything diesel and cheap”. Could end up with one of those 70’s GM 6.2lL want-to-be diesel cars. Get a PU of any shape size or description, then you will have to start defending it to all the city folks who advocate mini-cars on the newsgroups. :( You will also get the glaring looks (if you are driving a PU w/Wyoming plates) when you travel to Denver as you go past Boulder. Hope you store it far away from the main living quarters because it is very flammable. Just like storing barrels of gasoline next to your house. Have you ever actually looked into this? Diesel is NOT as flammable as gasoline.

Key word is “NOT as”. Flash/vapor point of diesel is a bit higher than gas but still very flammable. Yes, I’ve looked into it and work around petroleum products nearly all my adult life. Have you ever tried putting out a five gallon diesel spill fire? Let alone a drum or two full of it? I was thinking in your enclosed garage where vapors and spillage could collect and you are thinking (guess here) in a 250gallon tank beside the house like they do in the East. OK. Sure it needs to be stored appropriately, and not in a living

Response:

For my house during the summer time we only use 215 KWh per month, and we have an electric water heater and stove. At some point I plan on getting a grid-tied system that will equal this. Then I don’t have to worry about any utility bills at all. I see where you are coming from. I want to be as self sufficient as possible.

Response:

A few recommendations from a neighbor from the North. I don’t know build solar hot water heater how USA rates home insulation efficiency but I know Canada recommends builders to build homes that meet the R2000 standard. Maybe a search in Google will bring up more information on this standard. Now just recently, I was watching the Discovery Channel and saw a profile on a couple who built a Victorian style home that was 30% more efficient than a R2000 home. This is quite impressive and it pays for itself in a short time frame. The windows he mentions are fairly new technology and I know that at least Kohler (http://www.kohler-windows.com/) makes them. You can see a video clip on this by going to Discovery’s website at www.exn.ca You will have to search for “energy home” and click on the first search result returned. You’ll need Windows media player to view it. I also saw another program from this channel where a guy in Toronto built a house in the city without hooking up to the city services. He collected his water from rain, treated it, and stored it in tanks. His waste water was treated within the house and reused for non-hygienic related items such as washer, dishwasher and toilet. Excess water would just be discharged into the garden. His electricity came from solar panels. The house was designed to get the most of the heat from the sun. Unfortunately, Discovery’s website doesn’t have this clip available. Maybe I was dreaming this If you go to www.homepower.com , you’ll see an article on using solar water panels to heat up your household water. Personally, I feel this is the way to go for heating water. You’ll still need a second water heater to pick up the slack on those cold windy days. My next approach would be to pick a proper combination of solar and wind power. (Hydro generators too if possible) The first thing to realize is that it is cheaper to save power than it is to produce it. The second thing would be to understand your energy requirements on a yearly, monthly, daily, and hourly basis. Then determine what combination of RE generating devices will match your power requirements. Solar energy has the advantage that it produces it when you need it. In the daytime. It doesn’t work too well on a cloudy day and that’s where wind power comes in. Wind and clouds generally go hand in hand. At least where I live so the two are a good match. The next phase would be to have a proper back up when the solar and wind fail. The power company, a fueled generator, or battery backup are some of the options. At this stage of the game, costs, maintenance, reliability, location, and many other factors come into play. But I’m sure a little more research will reward you with some feasible designs. You never know, you might make some money by selling power back to the grid. The technology is there and waiting to be used. If only government and the power companies would encourage it. But that’s another topic. Hope all goes well. I’m definitely not an expert on the topic so I really want some feedback since I’ve only been research home energy for a couple of weeks now. I will also be building a house sometime in the near future.

Response:

Start the diesel whenever you want to make a cup of tea? Naaaah, the microwave will be fine for that. But I’ll probably run the genset when I’m cooking dinner and using the stove and two burners. ;)

Is this going to be a solar or wind powered microwave? And you will be adding CO2 to the atmosphere. Only what the plants took out of the atmosphere originally — one of the

big advantages of biodiesel is the zero net CO2. I have a problem with the assumption that by burning biodiesel, you get a nett zero CO2. This will only happen if the ground on which the diesel plants are cultivated, remains bare if some other fuel is used. If this ground it is cultivated with any plant for whatever use, the addition to the CO2 production will remain much the same as for petrodiesel, or do I have it wrong?

Response:

I am really curious how it “pays for itself in a short time frame”. I hear this all the time from people advocating additional insulation and such, but I no longer believe it based on my own experience. I pay about $600 a year for gas heat. I have an average size house (3br, 2 bath ranch). If I were to put in an attic blanket, I’d get maybe a 10-20% reduction in heat loss, but the cost would be in excess of $1000 for the insulation build solar hot water heater. You never really recover enough money in savings to justify the added cost.

Hi Bob, I assume you’re just pulling numbers out of the air, but let’s go with the numbers you gave here. A 10-20% reduction in fuel cost would mean $60 to $120 per year. So, just figuring simple payback, it would take between about 8 and 17 years to recover your money. I sure hope most houses will last much longer than that. I recently spent a rather unpleasant day crawling around the attic of our new (old) house, adding R20 to the existing spotty R12 insulation. Cost me $500. I don’t know how much money it will save me, but it was definitely worth doing (though I sure didn’t enjoy it!).

I am really curious how it “pays for itself in a short time frame”. I hear this all the time from people advocating additional insulation and such, but I no longer believe it based on my own experience. I pay about $600 a year for gas heat. I have an average size house (3br, 2 bath ranch). If I were to put in an attic blanket, I’d get maybe a 10-20% reduction in heat loss, but the cost would be in excess of $1000 for the insulation. You never really recover enough money in savings to justify the added cost.

Insulation and conservation methods work on the rule of diminishing returns. Your heating bill is already pretty good so you must already have some insulation/conservation techniques in play. But as I said, it follows the laws of dimishing returns. If your heating bill were $280/month, a thousand dollar investment that saves $100/month could pay off in just a couple of heating seasons. But the second thousand dollar investment would *not* save an additional $100/month. Might only save $60. And the third thousand dollar investment might only save $15/month and would take more than 16 heating seasons. Even if each time you put insulation in the attic you were to double the insulation already there, you would never get the heating bill to zero. And the cost of doubling the insulation would, of course, double each time you did it.

Response:

Even if each time you put insulation in the attic you were to double the insulation already there, you would never get the heating bill to zero…

Au contraire. You would, if you used any electricity in the house. Nick

Response:

Even if each time you put insulation in the attic you were to double the insulation already there, you would never get the heating bill to zero… Au contraire. You would, if you used any electricity in the house.

I beg to differ. If the house conforms to common building codes, it will have windows amounting to 10 percent of its floor area. Since these will rarely have an R value in excess of 4, incidental heating is unlikely to bring the required makeup heating needed to counter loss through the windows to zero in any climate where people would consider adding lots of insulation to the attic.acuum solar hot water heater

No readily-available wood unless we buy it and keep it on hand. Whereas I hope we WILL have biodiesel stored on-site to run an oil heater.

If you have bio-diesel I ASSume you have some oil crop. Why not just burn the crop for heat? What’s to gain by processing out the bio-diesel? (I have NEVER seen bio-diesel realistically priced at less than petro-diesel and usually it is about twice petro-diesel.) Burning corn, for example, as fuel can be cost effective under certain circumstances.

Response:

OK. I agree with you. If the house conforms to common building codes, it will have windows amounting to 10 percent of its floor area.

I’d say 8%, or maybe 4%… Since these will rarely have an R value in excess of 4, incidental heating is unlikely to bring the required makeup heating needed to counter loss through the windows to zero in any climate where people would consider adding lots of insulation to the attic.

Weasel words… Attic insulation alone may not do it. A friend who squeezed foam insulation board into most of his window frames has very low heating bills… Say we caulk up an A ft^2 square 1-story house really tight to make 0.2 Air Changes per Hour. If it has R48 SIP walls and ceiling and R10 foamboard (2″ of Styrofoam, or thinner double-foil foam) in most of the windows, its conductance will be 0.08A/R14 for windows plus A/48 for ceiling plus 0.2×8A/55 for air leaks plus (8×4sqrt(A)-0.08A)/48 for walls, ie G = 0.05397A+0.66666sqrt(A) Btu/h-F. If half of the windows face south, with 50% solar transmission, and they collect 500 Btu/ft^2 of sun on an average 30 F January day in Phila and lose 6h(75-30)/R4 = 68 Btu/ft^2-day (when warm air between the foamboard and the window rises up and escapes into the room through small holes near the top of the foamboard), and the internal electrical usage is 600 kWh/mo (68K Btu/day), and the daily heat gain E = 68K+17.3A = 24h(65-30)G = 840G, A = 1,627 ft^2, a small house. How big could it be with R20 windows? Nick

Response:

A friend who squeezed foam insulation board into most of his window frames has very low heating bills… I presume you refer to night shading here rather than permanently blocking windows.

Well, maybe he unblocks the north windows in summertime. Say we caulk up an A ft^2 square 1-story house really tight to make 0.2 Air Changes per Hour. If it has R48 SIP walls and ceiling and R10 foamboard (2″ of Styrofoam, or thinner double-foil foam) in most of the windows, its conductance will be 0.08A/R14 for windows plus A/48 for ceiling plus 0.2×8A/55 for air leaks plus (8×4sqrt(A)-0.08A)/48 for walls, ie G = 0.05397A+0.66666sqrt(A) Btu/h-F. I presume you meant to use R4 windows here.

The R10 board is inside the R4 window. If half of the windows face south, with 50% solar transmission, and they collect 500 Btu/ft^2 of sun on an average 30 F January day in Phila and lose 6h(75-30)/R4 = 68 Btu/ft^2-day (when warm air between the foamboard and the window rises up and escapes into the room through small holes near the top of the foamboard), and the internal electrical usage is 600 kWh/mo (68K Btu/day), and the daily heat gain E = 68K+17.3A = 24h(65-30)G = 840G, A = 1,627 ft^2, a small house. How big could it be with R20 windows? …with R20 windows, I doubt you would be getting 50% solar transmission.

This might work better with R1 windows with 90% solar transmission and R20 foamboard inside. With 0.08A/R24 for windows plus A/48 for ceiling plus 0.2×8A/55 for air leaks plus (8×4sqrt(A)-0.08A)/48 for walls, G = 0.051591A+0.66666sqrt(A) Btu/h-F. On an average day, a square foot of window might collect 900 Btu and lose 6h(75-30)/R1 = 270, for a 630 Btu net gain… 68K+630×0.04A = 24(65-30)G makes A+30.88sqrt(A)-3760 = 0, and substituting B = sqrt(A) in the quadratic formula makes B = 47.79, so A = 2284 ft^2. Better… …I would like to know where to get reliably R4 windows with transmission that high.

Gathering that kind of data is difficult. (The vendors I have found provide no guarantees on the lifetime of argon fill.)

You might do almost as well with low E-hardcoat. I also wonder why you use a 6 hour shaded period. I think the winter nights are much longer than that in North America.

That’s an estimate for the average daily solar collection period in January in Phila. Finally, I’d sure love to get my electricity usage down to 600 kWh per month.

Steve Baer uses 80.acuum solar hot water heater

Response:

Thanks, that’s refreshing. If the house conforms to common building codes, it will have windows amounting to 10 percent of its floor area. I’d say 8%, or maybe 4%…

Yes. The 10% requirement is only for certain rooms of a house, so my figure overstates the necessary window area. Kitchens, bathrooms and closets will usually have less, especially in a house designed for thermal economy. Since these will rarely have an R value in excess of 4, incidental heating is unlikely to bring the required makeup heating needed to counter loss through the windows to zero in any climate where people would consider adding lots of insulation to the attic. Weasel words… Attic insulation alone may not do it.

Try to be polite, Nick. I’m only trying to exclude climates with so little need for heating that incidental heating would be enough without any heroic effort. A friend who squeezed foam insulation board into most of his window frames has very low heating bills…

I presume you refer to night shading here rather than permanently blocking windows. Say we caulk up an A ft^2 square 1-story house really tight to make 0.2 Air Changes per Hour. If it has R48 SIP walls and ceiling and R10 foamboard (2″ of Styrofoam, or thinner double-foil foam) in most of the windows, its conductance will be 0.08A/R14 for windows plus A/48

for ceiling plus 0.2×8A/55 for air leaks plus (8×4sqrt(A)-0.08A)/48 for walls, ie G = 0.05397A+0.66666sqrt(A) Btu/h-F.

I presume you meant to use R4 windows here. If half of the windows face south, with 50% solar transmission, and they collect 500 Btu/ft^2 of sun on an average 30 F January day in Phila and lose 6h(75-30)/R4 = 68 Btu/ft^2-day (when warm air between the foamboard and the window rises up and escapes into the room through small holes near the top of the foamboard), and the internal electrical usage is 600 kWh/mo (68K Btu/day), and the daily heat gain E = 68K+17.3A = 24h(65-30)G = 840G, A = 1,627 ft^2, a small house. How big could it be with R20 windows?

Well, with R20 windows, I doubt you would be getting 50% solar transmission. In fact, I would like to know where to get reliably R4 windows with transmission that high. (The vendors I have found provide no guarantees on the lifetime of argon fill.) I also wonder why you use a 6 hour shaded period. I think the winter nights are much longer than that in North America. Finally, I’d sure love to get my electricity usage down to 600 kWh per month.

Response:

Finally, I’d sure love to get my electricity usage down to 600 kWh per month.

Response:

That should have been ‘January usage’. Really? Do you heat your house with electricity?

No, but the electric clothes dryer gets used a lot during the rainy season here. We live a pretty normal life in our house, and use about 7KWh/day (210KWh per month). Maybe you’re averaging in summer air conditioning?

Nope. We don’t use our air conditioner (silly thing came with the house — anybody want to buy a hardly used central air conditioner near Kitchener-Waterloo in Ontario, Canada?).

After installing a light colored roof, we hardly think of wanting any AC.

Response:

Finally, I’d sure love to get my electricity usage down to 600 kWh per month. That should have been ‘January usage’. Really? Do you heat your house with electricity? No, but the electric clothes dryer gets used a lot during the rainy season here.

Ah, that would take a big chunk. I’m blessed with a wife who doesn’t mind hanging the laundry build solar hot water heater to dry, indoors or outdoors, depending on the weather. We live a pretty normal life in our house, and use about 7KWh/day (210KWh per month). Maybe you’re averaging in summer air conditioning? Nope.

We have replaced all our commonly used light bulbs with compact fluorescents. We also heat primarily with a wood stove, so no power to run any big furnace blower. And we have a gas water heater — makes a big difference. In our old house with an electric hot water heater we used to run about 15K-18Wh/day. We do still cook with an electric range, though I hope to install a gas range soon.

Response:

Well, all depends. Do you wnat ac? You’d be better off with a solar water heater than electric, solar panels are, what, 15% efficient? Will the electric company pay you for extra power, or do they just get to keep it. If the latter, they are probably going to have a say-so in the size. Also, you are going to need many panels if you plan to use ac and size it to the peak demand.

Response:

I think we could skip the AC….the temperatures don’t seem to be as bad as where we are at (higher elevation and better breeze, I think is what does it). The designer was talking about putting in a heat pump, which I am told gives you both cooling and heating, although I’ve never used one. The util co keeps any excess electricity you generate so sizing the system properly is a major concern. As for using the AC or heat pump or whatever we end up with, my understanding is that the utility power will pickup any slack in our PV system.

Response:

Will be a lot of slack with a heat pump, unless it is ground source and even then you could well be talking a very large solar system. It would be simpler to go propane for heat and forget ac.

Response:

Your designers idea of a heat pump is not going to work well with solar. My home has a 5 ton 12.0 seer unit. Running amps is 22, locked rotor or starting amps is 89. Arizona Public Service has a solar play ground 3 miles from my home they have heat pumps running on solar, but they have 15 horse gensets sitting next to them because of the starting current. Works flawlessly, ya got $500k for the system. Be realistic, IF you can convert most of your appliances to gas do so, especially cooking water heating and heating in general. You can run most of the rest of the home on 12-24 volts. The biggest problem you will face is the washing machine, heat pump freezer and refer. Washing machines can take out generators when they go into spin cycle. A Arizona Public service sells a unit that looks like one of those shipping containers, with a propane powered generator all ready connected for charging. I don’t remember the price exactly, something like 10kw of solar for $25000.00. Your intentions are admirable. Do some more research, trying to run a home on dc is a night mare, let alone the increase in cost of the wiring. My opinion only Alan
Will the electric company pay you for extra power, or do they just get to keep it. If the latter, they are probably going to have a say-so in the size. Also, you are going to need many panels if you plan to use ac and size it to the peak demand. I think we could skip the AC….the temperatures don’t seem to be as bad as where we are at (higher elevation and better breeze, I think is what does it). The designer was talking about putting in a heat pump, which I am told gives you both cooling and heating, although I’ve never used one. The util co keeps any excess electricity you generate so sizing the system properly is a major concern. As for using the AC or heat pump or whatever we end up with, my understanding is that the utility power will pickup any slack in our PV system.acuum solar hot water heater

Category Categories: solar hot water heater | No Comments »

Price for Solar servamatic solar hot water heater systems Thermal?

Question:

servamatic solar hot water heater systems, installation and permits included, should a high quality 4X10 solar thermal panel with a photovoltaic panel running the circulating pump with a 80 gallon storage tank cost in total? Install is in South Florida so only need minimal freeze protection. How much for a pool solar system installed with eight 4X10 panels with an automatic controller? I’m talking installed by the same company. I don’t want to buy a system then hire a plumber.

Response:

Typical installation around Ft. Myers is about $2700 for pool system. I installed my own for MUCH less.

servamatic solar hot water heater systems- How much, installation and permits included, should a high quality 4X10 solar thermal panel with a photovoltaic panel running the circulating pump with a 80 gallon storage tank cost in total? Install is in South Florida so only need minimal freeze protection. How much for a pool solar system installed with eight 4X10 panels with an automatic controller? I’m talking installed by the same company. I don’t want to buy a system then hire a plumber.

Response:

I just had several estimates in the Tamp bay area ranging in price from $1900 to $2900 for a solar pool heater. Materials alone to match the high priced ”’best”’ system was about $1400 which puts the labor cost and markup in the $1500 range. Anyone capable of reading and understanding high school level English/instructions should be able to do a DIY install. I personally would advise against a ’store bought’ solar hot water heater system in the Tampa area. I have yet to find anyone that will give an ‘excellent’ recommendation to any of the contractors around here but have heard a plethora of horror stories. Hope this was helpful!

servamatic solar hot water heater systems

servamatic solar hot water heater systems How much, installation and permits included, should a high quality 4X10 solar thermal panel with a photovoltaic panel running the circulating pump with a 80 gallon storage tank cost in total? Install is in South Florida so only need minimal freeze protection. How much for a pool solar system installed with eight 4X10 panels with an automatic controller? I’m talking installed by the same company. I don’t want to buy a system then hire a plumber.

Response:

How much, installation and permits included, should a high quality 4X10 solar thermal panel with a photovoltaic panel running the circulating pump with a 80 gallon storage tank cost in total? Install is in South Florida so only need minimal freeze protection. How much for a pool solar system installed with eight 4X10 panels with an automatic controller? I’m talking installed by the same company. I don’t want to buy a system then hire a plumber.

I could only guess. Labor depends on your area which I am not at all familiar. Here in AZ I would venture to guess that the hot water system would be about $4-5K as long as you do not have a concrete tile roof. Plumbers are $50-75 an hour. My last visit with one 3 hours was $225 for labor only, they charge a trip charge now. I personally would not bother with the photo panel for the pump and just use utility power for it. Less parts to install and maintain. I just paid ~$500.00 for a Lockinvar 80 gallon tank, old one crapped after 10 or so years. The pool system is far harder to ascertain. Distances to the roof, are you going to build a stand to hold the collectors, trenching, concrete? Drive about and look at installations near your home. Talk to the people and get recommendations.

servamatic solar hot water heater systemsGet at least 3 bids, and ask for references. Then check your local contractor licensing department when you have narrowed the field. One or two will rise like cream to the top. They may or may not be the least expensive. I have found that you do get what you pay; for to an extent. The cheap price is not necessarily the best price. Best of luck

Join the Solar Power Revolution!

All about the amazing world of solar panels!

Topics

Posts belonging to Category 'solar hot water heater'

Tankless Solar Panel Inverter batterey Water Heater

Question:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Newbie Ignorant Questions solar hot water heater orlando

Question:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

build solar hot water heater System On New House?acuum solar hot water heater

Question:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response:

Response: