Question:

TTI’ve always been taught and read that solar power is too inefficient to TTbe used as a power source beyond subsidization of other power. TT        I’m also aware that it’s quite cost-inefficient.solar hot water heaters tucson  TTCan anyone change my viewpoint? Trish,  despite  the misinformation coming from Brian  K.  Yoder, solar  power has many uses other than the ones he cites.  In  the first place, nearly every communications, weather, reconnaissance (or what have you), satellite in space is powered by photovoltaic (PV)  power.solar hot water heaters tucson  Many remote microwave communication towers  are  PV powered.  Thousands  of homes, mainly in the west and  mainly  in northern  California,  are powered by PV. There is even  a  small town  in Arizona running on PV power. The PV market is in  excess of  $380  million  and increasing 15%  annually.  Some  optimists project a $2 billion market by 1999. The main use of solar power on good ol’ Terra these days is  sup- plying  power to homes, farms and other facilities that are  more than  a  third of a mile from lines connected to  a  grid.  ”Home Power  Magazine” cites many such cases. Costs are coming down  so that  every  year that distance gets  reduced.  Solar  Technology Institute in Carbondale, CO is one of a number of a well attended schools teaching the techniques. There   about   a  half  dozen  companies,   including   Siemens, Solarex(Amoco), Kyocera, and Hoxan, that produce single  crystal, polycrystalline  or multi- junction amorphous photocells  running 10%-15%  efficiency, used in applications cited above. Panels  of cells can be obtained for $4.5 to $6.5 per peak watt. As far as grid power is concerned, the  Sacramento (CA) Municipal Utility  District  has been operating  ground-mounted  PV  arrays since  1985.  The Photovoltaics  for  Utility-Scale  Applications (PVUSA) is a continuing effort of the U.S. DOE, California Energy Commission, Electric Power Research Institute (EPRI), and Pacific Gas  and  Electric Company in a facility near Davis, CA  to  test photovoltaic systems for grid use. As  far as efficiency is concerned, Boeing has obtained a  record 40%  with  a Gallium Arsenide (GaaS) cell. The Solar  Energy  Re- search Institute (now the Renewable Energy Research Institute), I believe, has a GAAS design that has reached 36%. But these  cells are relatively expensive to produce. A  more promising approach is a cell developed at  Stanford  Uni- versity  with EPRI financing and now being produced  by  Sunpower Corp.  of  Sunnyvale, CA. This cell uses  point  contact  silicon technology  that reaches 30% efficiency at 500 suns.  They  claim that the present cost of $10 per peak watt will be down to  $1.50 in  1996. They also claim they will be able to deliver  power  at $0.06  to  $0.07  per kilowatt-hour,  competitive  with  nuclear. Sunpower’s  ultimate plan is to produce  turn-key  multi-megawatt power stations. They have contracts to develop two test installa- tions, a 250 kw in late 1992 and a one megawatt  installation  in 1993. So  Trish, if institutions like EPRI seem to feel that  PV  solar power  has a future with the utilities, it can’t be that  ineffi- cient. There is lots of developement going on. The future is bright as far as solar is concerned, pun intended.solar hot water heaters tucson

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Yes, we don’t know the effects of large areas of solar collectors. But we know that in small scale they shouldn’t be a problem. Putting solar cells and solar collectors on a roof will not change the global climate! solar hot water heaters tucson

Putting solar collectors on roofs MIGHT change the local albedo enough to increase/decrease the urban heat island effect.  And unless the energy to manufacture and transport the components is “pure” solar, it might also contribute the global CO2 and possible climate changes.  Not too mention any pollutant by-products of manufacture that might be greenhouse gases.solar hot water heaters tucson

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Is this based on any facts or just your prejudices?  Do you think that running a semiconductor facility is easy?  Cheap?

You can’t compare the precision manufacturing required for VLSI production with the simple PN junction required in a solar cell. In principle, it can be very cheap to produce a solar cell wafer.solar hot water heaters tucson

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Putting solar collectors on roofs MIGHT change the local albedo enough to increase/decrease the urban heat island effect.

Most roofs are pretty dark right now,solar hot water heaters tucson  so I don’t think replacing them with PV collectors would change anything much.   And unless the energy to manufacture and transport the components is “pure” solar, it might also contribute the global CO2 and possible climate changes.  Not too mention any pollutant by-products of manufacture that might be greenhouse gases.

Compared to the CO2 and byproducts of manufacturing conventional power plants? Not to mention their operation. Having lots of low efficiency (low temperature) solar collectors in an area might cause *more* heat pollution than a few high temperature (and high efficiency) fossil fuel heat sources.

I doubt this very seriously.  With PV’s you are dealing with only the incident sunlight.  With conventional power plants, you have the same incident sunlight plus the additional heat created by combustion and work performed by the conventional (or nuclear) fuels.  And if there were a local heating effect from a bunch of hot roofs, they could be insulated and designed to reradiate their heat upward to reduce the effect.  Additionally you could use an IR reflective coating, or if that fails,solar hot water heaters tucson

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However.  Many utilities pay more for their power,solar hot water heaters tucson  and charge much more than this, especially to residential users.  There’s a real possibility that cheaper PV arrays will place a ceiling on utility rates, beyond which they go only at the risk of permanent loss of demand.  It’s possible we could see some utilities entering a “death spiral” of reduced demand leading to higher rates, and ultimately to bankruptcy (cogeneration is another, perhaps more likely, road to this end).

This is an interesting point. This means WE can force solar power (not only PV) to be more competitive by saving energy and doing cogeneration. This will kick the utilities out of the market. [ In germany is a small town which has bought the local power network from the utility and is generating its own energy by using alternative power sources (mainly wind) and more efficient small combined heat/electricity generating power stations.solar hot water heaters tucson

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Solar power, at least at the small scales at which it has been tested,

Solar power is already in use for more than 10 years, especially for warming up water. There are a lot of solar collectors used here in germany. If you mean electricity generated from solar energy (PV or thermal) than you might be right. does indeed reduce some pollutants over the use of fossil energy.

The only pollutants are generated during production.solar hot water heaters tucson  A lot of energy is needed to produce solar cells and this energy is generated by fossile or nuclear power plants. If we can generate a high degree of energy by alternate power sources we can reduce the pollutants drastically! However, the horseless carriage was hailed at the turn of the century as the salvation of the city because of reduced pollution versus the horses then in use. We can't be sure that large areas of solar collectors won't have some adverse effect on the environment in the future. (I am not seriously proposing that this is true, but it is a possibility that must be considered.)

Yes, we don't know the effects of large areas of solar collectors. But we know that in small scale they shouldn't be a problem. Putting solar cells and solar collectors on a roof will not change the global climate!solar hot water heaters tucson

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and you need some kind of storage system to allow the power generated on sunny days to be used at night or on cloudy days.

Nuclear plants like to run at full throttle, so (at least at Diablo Canyon here in California) the excess power is stored by pumping water uphill between resevoirs at different elevations at night. During the day, the stored energy is extracted by running water through turbine generators to augment that produced by the nuclear plant.    solar hot water heaters tucson

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[ some lines deleted ] (1) is clearly false.  In the US (for example) the total amount of sunlight hitting the country in a year exceeds primary energy consumption by a factor of 500.  So,solar hot water heaters tucson with 10% efficient PV cells, and assuming the primary energy is replaced by PV electricity 1 for 1, we’d naively need to cover 2% of the country with collectors.  This is small compared to the area covered by, say, farms.solar hot water heaters tucson  You make it sound like this land is being used for nothing and has no competing demands.

What are the competing demands for roof tops? (Has been mentioned before)                       You also have to remember that less than 100% of the land in a big collector farm would be covered by panels,

Why do we need big collector farms? This sounds like another big technology monster like nuclear power plants (don’t flame me). Why not doing development step by step, by first doing anything possible to conserve energy and then using the areas on roofs for solar energy (collectors and PV). A institute here in germany is currently building a ZERO energy house. This means it doesn’t need any energy in addition to what is generated by the house itself. I know, that’s to expensive currently, solar hot water heaters tucson. That’s unfair! Her is the point were a government should act and “ram it down our throats” by making the environmental bad and unsustainable energies more expensive by taxes and use the money to force alternative energy (solar, wind, biomass, water) into the market. But don’t forget, energy conservation can currently “produce” more energy than any alternative power source in the near future.solar hot water heaters tucson.  I might as well comment on the persistent issue of toxic chemicals in semiconductor manufacturing. Yes, there are a number of things you don’t want to breathe or soak your corns in. No, we don’t put them down the sink. Every day I walk past acres of double-retention holding tanks in which the spent chemicals are segregated by type for purposes of reclamation. Further, there are three dopants generally used in Si circuits – B, P and As. You could get by without As if you had simpler processing. It’s only needed when you have to put down a layer that won’t move through the rest of the processing. You could make solar cells with only B and P which are relatively benign. I’ll reiterate at this point that I am not a responsible spokesperson for my employer.  What is lacking to some extent is large volume, low-cost manufacturing of PVs. There are a few houses in that business and even these find that the best route to profitability is to pursue markets where they can add additional value and run less product. The last thing they want to do is be in a price war; most of them appear to be marginally profitable as it is.  In my opinion the traditional one-cell-per-wafer production method is a dead end. Some companies are already producing continuous sheet PV material. These companies know better than to sell it at Home Depot by the roll; they sell it to OEMs who use it in -their- products.  If you wanted to be a broke humanitarian you could buy some used equipment and run a sloppy wet single-junction, single metal process and make a mess of 10% solar cells and sell them for a buck each.solar hot water heaters tucson

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.        I’m also aware that it’s quite cost-inefficient. Can anyone change my viewpoint? How about this: 1.  The main material (silicon) is easily available in abundant supply without requiring drilling, strip mining, disposal of toxic waste,solar hot water heaters tucson

Actually, my understanding is that the processing uses some pretty nasty toxic chemicals.  Where did you get your information? What about all of the other materials?  You seem to be focusing in on one small part of the system and one small part of the cost without considering the system as a whole. 2.  Solar cells are indeed cost-inefficient to make at present, but apparently only due to labor-intensive manufacturing methods.solar hot water heaters tucson  There are no fundamentally expensive processes involved.  In particular, the heat required to melt the silicon can be recycled in an efficient manufacturing plant.  Mass production has a wonderful way of reducing the cost of products to the point where packaging, advertising and distribution become the dominent costs.

Is this based on any facts or just your prejudices?  Do you think that running a semiconductor facility is easy?  Cheap? 3.  Who cares if solar power is inefficient if it is free?

Think a bit will ya?  It ISN’T free!  If I gave you a machine that would power your house for a year using only a single drop of water as fuel, would you consider it “free” is the machine wore out after a year and cost a million bucks?  Of course not.  Again, you are focusing in on one tiny aspect of the system (the fuel cost) and ignoring everything else.  Why do you think that efficient use of fuel is so important, while labor, materials, support systems, and capital are unimportant? Solar electricity is NOT free!solar hot water heaters tucson  It’s darned expensive! 4.  The country with cheap energy has a competitive advantage in the world.

Hogwash!  There you go again focusing on a tiny detail and ignoring everything else.  Energy is a resource no different from any other.   Cheap resources, good management, good designs, available capital, high workers productivity, intellectual freedom, and property rights are all important factors in relative economic advantage.  Energy costs are a TINY factor in the bigger picture. All that said, solar power is NOT cheap, so even if your theory were correct, it still wouldn’t apply to solar electricity. 5.  solar hot water heaters tucson

Actually, that kind of useless make-work projects prolonged the depression a few years!  Just think how much more stimulating to the economy all that labor would have been if it had been directed toward the production of goods and serices someone actually wanted and could pay for! In the meanwhile, the country got a terrific network of highways and hydroelectric plants which we all still benefit from.

Do you know what cost-benefit analysis is?  I didn’t think so. I propose a similar program to manufacture solar cells and plaster every roof in the sun belt with them, both to provide jobs and to promote this country’s future.

You sound like Jerry Brown.  Look, where are you going to get all that money? Every dollar you take from someone to pay for this will either be one less dollar invested in the production of real goods and services people want, or it will mean a decrease in demand for products which means less demand for the labor to produce those products. Why not just have a program to put millions of people to work digging holes and filling them in again?  That would “Generate jobs” like crazy!  Wouldn’t it? Do you think that we have a big shortage of electricity today?solar hot water heaters tucson  Do you think we lack peak production capacity?  Remember, rooftop collectors won’t do you any good at night, you you still need to have all those power plants there to work the night shift (that, or you also need to build big energy storage systems which are also very expensive and inefficient. It would require strong government support in terms of tax incentives and outright subsidies, because industry wouldn’t support it (sunlight is free; the technology is public domain; so it’s impossible to maintain a monopoly).

That is simply nonsense.solar hot water heaters tucson  If I had a small cheap device that could produce lots of electricity, there would be hundreds of companies crawling all over one another to market it.  I don’t know what more to say.  Learn some economics and some common sense. Indeed, it would even take some arm twisting to get government to support it since they would lose tax revenue.

Even more nonsense.  The government has been subsidizing solar power projects for years (though I have heard that they have cut back a bit in recent years). The problem with them is that they make no economic sense, and nobody would voluntarily use them for electricity generation. Even if the technology was highly competitive, having it proliferate would NOT decrease government tax revenues!  It would increase them.  Lower operating costs result in higher productivity and MORE tax receipts.  Learn some economics and some common sense. 6.  Plus all the usual benefits of solar energy–reduced pollutants, no global warming gasses,solar hot water heaters tucson

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If you are refering to the Luz plants, note that with the financing available to utilities and no tax breaks, they would produce electricity for about $.12/kWh.

Do they cost more to operate than non-solar gas-burning facilities? If so, why?  If they don’t need to burn as much gas during the day because they’re collecting solar heat, then they should operate more cheaply…  unless their maintainance costs are higher or they cost a lot more to build. — “This coffee is my blood, this breakfast burrito is my flesh.  And  it cost me 89 cents, so get your goddamned own.”solar hot water heaters tucson

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2.  Solar cells are indeed cost-inefficient to make at present, but apparently only due to labor-intensive manufacturing methods.  There are no fundamentally expensive processes involved.  In particular, the heat required to melt the silicon can be recycled in an efficient manufacturing plant.  Mass production has a wonderful way of reducing the cost of products to the point where packaging, advertising and distribution become the dominent costs.

While better manufacturing methods are no doubt possible, the semiconductor industry is already highly automated. Most of the labor is in packaging. 3.solar hot water heaters tucson  Who cares if solar power is inefficient if it is free?

Inefficiency is never free. 4.  The country with cheap energy has a competitive advantage in the world.

See Japan or Europe where high energy costs don’t make them uncompetitive. I agree in spirit with this claim that cheap energy aids competitive position, but it isn’t totally a black and white situation. 5.  The CCC helped to pull the country out of depression in the 30’s. In the meanwhile, the country got a terrific network of highways and hydroelectric plants which we all still benefit from.

Go study depression era economic data again. The US depression was deeper in 1940 than in 1932. It was WWII that pulled the US economy out of the Great Depression.solar hot water heaters tucson  Government programs like CCC may have actually *retarded* a normal economic recovery. For sure they started the US down the road to a trillion dollar debt as ponzi schemes like Social Security have cascaded into the present. I propose a similar program to manufacture solar cells and plaster every roof in the sun belt with them, both to provide jobs and to promote this country’s future.  It would require strong government support in terms of tax incentives and outright subsidies, because industry wouldn’t support it (sunlight is free; the technology is public domain; so it’s impossible to maintain a monopoly).solar hot water heaters tucson  Indeed, it would even take some arm twisting to get government to support it since they would lose tax revenue.

Several points. First, the US economy now employs more people than at any time in US history. Using jobs as a welfare program has never worked. Only jobs that return an economic benefit higher than their cost are of benefit to the nation. No government jobs program has ever met this criteria. Spending government money (IE your money and my money) on an energy source more expensive than other available alternatives is unwise and unsound. The loss of capital to the nation means that every other user of capital will see increased costs.solar hot water heaters tucson  This cascades through the entire economy costing jobs and competitiveness. Finally, the technology as monopoly argument is bogus. Name one major manufactured product in the US that depends on monopoly technology.  Businesses make money by delivering products to people at a price that is more than the cost of production. The difference is called profit. Monopoly is not required to produce a profit. If it were, the oil companies would all be broke since the technologies for digging wells and refining oil are well known and mostly in the public domain. 6.  Plus all the usual benefits of solar energy–reduced pollutants, no global warming gasses, solar hot water heaters tucson

Solar power, at least at the small scales at which it has been tested, does indeed reduce some pollutants over the use of fossil energy. However, the horseless carriage was hailed at the turn of the century as the salvation of the city because of reduced pollution versus the horses then in use. We can’t be sure that large areas of solar collectors won’t have some adverse effect on the environment in the future.solar hot water heaters tucson

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If you are refering to the Luz plants, note that with the financing available to utilities and no tax breaks, they would produce electricity for about $.12/kWh. Do they cost more to operate than non-solar gas-burning facilities? If so, why?  If they don’t need to burn as much gas during the day because they’re collecting solar heat, then they should operate more cheaply…  unless their maintainance costs are higher or they cost a lot more to build.

Right the second time.  Compare the complexity, size and cost of a collector field to that of a gas-fired boiler (or even a gas turbine) of comparable heat rate.  The later SEGS cost about $3000/kW.  A cheap gas turbine costs maybe $500/kW.  They run on natural gas at the SEGS as much as they can (25% of thermal input, limited by the regulations governing their tax breaks).  Natural gas is still pretty cheap, especially in the summer.      solar hot water heaters tucson.  A nudge by the government should be enough to get the ball rolling. Finally, the technology as monopoly argument is bogus. Name one major manufactured product in the US that depends on monopoly technology.  Businesses make money by delivering products to people at a price that is more than the cost of production. The difference is called profit. Monopoly is not required to produce a profit. If it were, the oil companies would all be broke since the technologies for digging wells and refining oil are well known and mostly in the public domain.

However, the government’s policies WRT tax and legislation and leasing of public land has a lot to do with whether a profit is made.  Besides, I was referring to monopolies on a more local scale–the way things stand now, I have no choice but to buy my electric power from the one electric utility that servers me, at a rate I have no control over. However, the horseless carriage was hailed at the turn of the century as the salvation of the city because of reduced pollution versus the horses then in use. We can’t be sure that large areas of solar collectors

Can solar hot water heaters tucson.  Even 10-20% penetration is not chicken feed.   (2) is currently true, to some extent, but the cost/watt can be   reduced without increasing the efficiency at all, simply by finding   ways to make the collectors more cheaply.     It is also necessary to have storage systems to allow people to use electricity   at night, and these multiply the inefficiency and cost. This is only necessary if solar is to take up more than a certain fraction of electricity demand, a fraction that is nowhere near being filled.  Storage is not yet the constraint on PV cell market penetration.  In fact, improved storage would likely *harm* the PV cell market, by allowing baseload powerplants to supply peaking power.   Economies of scale would no   doubt apply to manufacture of collectors as they do to all other   manufactured goods.  DOE estimates that costs will fall 70% for every   tenfold increase in production experience and 40% for each tenfold   increase in annual output.  PV has many profitable niche applications,   and sales are growing about 20%/year in the US.   Economies of scale can help, but can’t necessarily make the product cheap or   economical.  This sounds like wishful thinking to me. No wishful thinking, just analysis of what goes into making PV modules (mostly labor, now), coupled with experience in just about all other industries.   Many people have looked at what can be done via automation as PV cell manufacture gets large enough to justify the investment.  Significant savings are possible. The fact that the PV market is so small no (about 55 MW/year production, worldwide) shows that there is a lot of room to run down that learning curve.   Module efficiency does affect balance of system costs (supports,   installation, etc.)  DOE thinks 15% efficiency is the goal to shoot   for for flat plate collectors.     And then what?  Will PV power be at a break-even relative to coal or nuclear?   Or is that the point at which they think they will be able to ram it   down our throats and accept the economic losses? If you look at the lowest cost coal and nuclear plants, then, no, I don’t think even this is immediately competitive, for the utility, for baseload power, especially if PV is compared to avoided costs (as low as $.01-.02/kWh for coal and nuclear plants).  This ignores capital cost and (for coal) the cost of scrubbing and CO2 emissions (if you want to include that). However.  Many utilities pay more for their power, and charge much more than this, especially to residential users.  There’s a real possibility that cheaper PV arrays will place a ceiling on utility rates, beyond which they go only at the risk of permanent loss of demand.  It’s possible we could see some utilities entering a “death spiral” of reduced demand leading to higher rates, and ultimately to bankruptcy (cogeneration is another, perhaps more likely, road to this end). A datum: in Rochester, NY, users using 25,000 kWh/year are being placed on time of use electric rates.  The rate during the 500-hour summer peak (weekdays, 11am-5pm) is nearly $.24/kWh.  PV systems need not decline in price by very much to be able to beat this price, even in Rochester.         Psolar hot water heaters tucson, note that with the financing available to utilities and no tax breaks, they would produce electricity for about $.12/kWh.  It was uncertainty about extension of the tax breaks that drove them to bankruptcy.  Their product was not competitive without the tax break subsidy, and they needed to keep building new units to maintain enough cash flow to stay in business.         Paul F. Dietz

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.    I’m also aware that it’s quite cost-inefficient. Can anyone change my viewpoint?

Solar power takes many forms. In the form of passive solar space heating, it is quite cost effective in many climates. In the form of active solar water heating, it’s cost effective in many areas. In the form of food preparation, solar drying and cooking, it’s viable in many areas. In the area of solar electric power, if the power demand is not too great, can stand interruptions, or is far from the grid, then solar photovoltaic generation is viable today. If the demand is for large amounts of power on an uninterrupted basis, at night, then solar electric power is not viable in most cases today. A high capacity solar installation, with adequate storage for nightime and extended overcast periods, is expensive, but, so is the extension of the grid to isolated locations. In most situations sun outages are frequent enough that auxillary backup systems are required. From wood stoves to diesel generators, some backup system is almost always warranted when solar power is contemplated as the primary energy source. Depending on fuel cost, the auxillary may be more cost effective than the primary solar installation in some cases, but there are situations where delivered fuel cost exceeds solar capital cost today. solar hot water heaters tucson

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.    I’m also aware that it’s quite cost-inefficient. Can anyone change my viewpoint?

How about this: 1.  The main material (silicon) is easily available in abundant supply without requiring drilling, strip mining, disposal of toxic waste, etc. 2.  Solar cells are indeed cost-inefficient to make at present, but apparently only due to labor-intensive manufacturing methods.  There are no fundamentally expensive processes involved.  In particular, the heat required to melt the silicon can be recycled in an efficient manufacturing plant.  Mass production has a wonderful way of reducing the cost of products to the point where packaging, advertising and distribution become the dominent costs. 3.  Who cares if solar power is inefficient if it is free? 4.  The country with cheap energy has a competitive advantage in the world.   5.  The CCC helped to pull the country out of depression in the 30’s. In the meanwhile, the country got a terrific network of highways and hydroelectric plants which we all still benefit from. I propose a similar program to manufacture solar cells and plaster every roof in the sun belt with them, both to provide jobs and to promote this country’s future.  It would require strong government support in terms of tax incentives and outright subsidies, because industry wouldn’t support it (sunlight is free; the technology is public domain; so it’s impossible to maintain a monopoly).  Indeed, it would even take some arm twisting to get government to support it since they would lose tax revenue. 6.  Plus all the usual benefits of solar energy–reduced pollutants, no global warming gasses,solar hot water heaters tucson

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assuming the primary energy is replaced by PV electricity 1 for 1, we’d naively need to cover 2% of the country with collectors. solar hot water heaters tucson. (1) is clearly false.  In the US (for example) the total amount of sunlight hitting the country in a year exceeds primary energy consumption by a factor of 500.  So, with 10% efficient PV cells, and assuming the primary energy is replaced by PV electricity 1 for 1, we’d naively need to cover 2% of the country with collectors.  This is small compared to the area covered by, say, farms. (2) is currently true, to some extent, but the cost/watt can be reduced without increasing the efficiency at all, simply by finding ways to make the collectors more cheaply.  Economies of scale would no doubt apply to manufacture of collectors as they do to all other manufactured goods.  DOE estimates that costs will fall 70% for every tenfold increase in production experience and 40% for each tenfold increase in annual output.  PV has many profitable niche applications, and sales are growing about 20%/year in the US. PV currently costs about $5/W (for modules) and $1-2/W for balance of system costs.  Modules cost will have to fall to $3/W for PV to compete for peaking power and $1/W to compete for bulk power. Module efficiency does affect balance of system costs (supports, installation, etc.)  DOE thinks 15% efficiency is the goal to shoot for for flat plate collectors.      solar hot water heaters tucson

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.    I’m also aware that it’s quite cost-inefficient.

There are certain limited exceptions, but you are basically correct. Sunlight is a very diffuse resource and collecting it and transmitting it to where it can be used is very expensive.  Certain people have a romantic attachment to the idea thaht blinds them to the facts (say, Al Gore for example). Solar power is OK as an assist for heating water in certain circumstances, but beyond that and powering calculators and remote weather stations, solar power is pretty useless compared to the alternatives. solar hot water heaters tucson

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.         I’m also aware that it’s quite cost-inefficient. Can anyone change my viewpoint?solar hot water heaters tucson

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I’ve always been taught and read that solar power is too inefficient to be used as a power source beyond subsidization of other power.

This depends on what your application is.  For anywhere in the lower 48,  it is more economical to build a new house to use passive solar than it is to install a new oil, gas or coal furnace and to fuel it for 20 years.  Passive solar conversions would turn a net profit for many existing homes,  but the investment is rather large.         Solar hot water heaters are also gaining in popularity here in New Mexico.  In some neighborhoods,  I’ve noticed that almost half of the houses are so equipped.  As the technology improves,  it becomes more and more practical in less favorable climates.  Solar hot water systems can work in places like Massachusetts,  but the cost of the system is more since one needs a larger,  better-insulated tank to hold over periods with no sun,  and typically more collector area (so you can heat that tank up very quickly when you ~do~ get sun).    I’m also aware that it’s quite cost-inefficient. Can anyone change my viewpoint?

I think that you’re specifically talking about the generation of electricity from solar,  which is still an embryonic technology.  You are partially right about it being inefficient,  but the technology ~is~ improving and has plenty of room to improve.  Existing solar thermal systems that use natural gas backup generate electricity for 8 cents/kWh, whereas TI claims that decentralized applications (potentially rooftop) of it’s Spheral Solar technology can beat 5 cents/kWh,  and I believe that Spheral Solar has about an 8%-10% conversion efficiency,  which is about the same as the photovoltaics you can buy today.  Spheral Solar is very similar in technology to existing PVs,  except for the fact that TI has developed a method of manufacturing that can use less expensive materials.         With more exotic technologies,  such as multi-layered thin films, efficiencies of over 30% have been attained.  There have been recent developments of photovoltaic cells based on somewhat different physics, such as dye-based solar cells,  that could also lead to higher efficiency and lower cost.         Even today,  there are plenty of places where PVs are competitive. Many of them are niche markets,  such as solar calculators,  but for applications far away from power lines (such as highway aid stations here in NM,  street lights in India,  some water pumping applications,  etc.), solar can be very competitive.  I’ve heard that solar becomes competitive with mains electricity if one has to string more than 1,000 feet of wire to attach to the grid. –

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