Here is what the acolytes of solar power don't want you to know...

self | July 15, 2003 | Boot Hill

[Boot Hill]

Here is what the acolytes of solar power don't want you to know...

These are the essentials you need in order to appreciate the absurdity of using solar cell power systems as any kind of sensible alternative. After you read this, ask yourself again how much sense solar power really makes.

THIS IS WHAT HAPPENS TO THE SUN'S ENERGY WHEN
WE USE SOLAR CELLS TO GENERATE ELECTRICITY:

	SOURCE	LOSS - %	POWER - W/m2
1.	solar constant	--	1370W
2.	atmosphere	27	1000W
3.	clouds	21	790W
4.	sun angle1	49	403W
5.	night2	50	201W
6.	cell efficiency3	85	30W
7.	dust/reflection4	10	27W
8.	packaging5	20	22W
9.	DC to AC inverter	25	16W
10.	storage	30	11W
Source Notes: 1.   Calculated for both hour angle and a latitude angle of 37º. 2.   See link. Continental U.S. average sunshine is 4.8 kilowatt-hours/       square meter/day, or 200 watts/square meter. That value is nearly       identical with total losses shown for items 1-5 above. 3.   See table on linked page. 4.   Dust, bird droppings, scratches, etc. estimated to be about 4%.       Reflections, per Fresnel's Law, would be another 6%. 5.   See link for data sheet on typical solar panel. Data shows an       overall efficiency of 10.3%, at nominal conditions. This is       nearly identical with total losses shown for items 6-8 above.

Net efficiency = 11.4 Watts/m² or a mere 0.83% (!)

But read on, it gets worse.

• The current average rate of U.S. energy consumption is about 3.3 trillion Watts. Based on the above efficiency data, we would need to cover the entire state of New Mexico with solar cells just to generate this amount of energy!   [+]

• And because of the 2% annual growth rate in our energy consumption, in only 35 years we would also have to cover the entire state of Arizona as well!   [+]

• And the irony is that the environmentalists, who are so obsessed with the use of solar power now, would be the first to scream bloody murder at the idea of such large areas of wild lands being permanently covered over with solar generating plants!   [+]   [+]   (Note: Both articles are written by the same author!)

• Worse still, the entire world-wide production of photovoltaic (PV) cells is so small (300 MW) that it can't even keep up with the annual U.S. growth rate in energy consumption (66,000 MW), much less produce enough PV cells to supply the base amount of energy that we currently use (3,300,000 MW). To do that, PV cell production would have to ramp up over 100,000%!   [+]   (Scroll down to chart)

• The initial capitalization cost of a solar PV generating plant is at least 10 times the cost of a large conventional plant. And that is exclusive of the mammoth land acquisition costs necessary to accommodate the vast expanse of solar cells.

  Here is an example:
  Siemens Solar (now Shell Solar) produces a popular line of large solar arrays intended for commercial, industrial and consumer applications. A big seller is their SP-150, supposedly a 150 watt unit that measures 1.32 square meters. The problem is, it only produces 150 watts under carefully controlled laboratory conditions where the incident light intensity is boosted to 1000 watts per square meter (unrealistically high, see items 2 and 3 in above table) and the PV cells are artificially cooled to 25º C. But when Shell tests that same unit under more realistic conditions of 800 watts per square meter and little cooling for the PV cells, the output drops to 109 watts. When sun angle and night time are factored in (see items 4 and 5 in above table), the average level of power production drops to a piddling 28 watts. (That is only 21 watts per square meter(!) which is nearly identical to the value shown for item 8 in the above table.)   [+]   [+]

  In quantity, this unit sells for $700. That calculates out to $25 per watt. By way of comparison, the initial capitalization cost for a conventional power plant is on the order of $0.75 to $1.00 per watt. That makes the solar "alternative" 33 times more expensive than the conventional power plants of today, and we haven't even figured in the additional cost of the inverters and power storage systems that solar needs (or the land acquisition costs).

  Solar proponents would be quick to point out that, while the capitalization costs may be higher for solar, they don't need to purchase the expensive fossil fuels that conventional plants use. While that is true, what they aren't telling you is that the cost of financing the much higher initial debt load for solar, is greater than the cost of the fuels that conventional plants use. (TANSTAAFL !)

• PV cells have a limited lifetime. As a consequence, manufacturers offer only limited warranties on power output, some as short as 20 years.   [+]

• A violent storm, such as a hail storm, can decimate a solar power plant. A storm covering only one square mile (the size of a small 50 MW solar plant) could destroy a half billion dollars in solar panels.

• PV cells have a nasty little habit of loosing conversion efficiency when you put them out in the warm sunlight. A hot day can lower the output power by up to 20%!   [+]

• A solar PV generating plant is not without maintenance. How are you going to wash the tens of thousands of square miles of PV cells of the dirt, dust and bird droppings that will collect over time? How will they be kept free of snow and ice during winter? A 1000 MW solar plant can lose 40 MW of power (retail value, about $50 million per year) by failing to keep the PV cells clean of dirt. Losses would be even greater for snow and ice.

• Solar PV generating plants incur inefficiencies quite foreign to conventional power plants. First, there is no need for energy storage in a conventional plant, as night time doesn't affect generating capacity. Second, there is no need for an inverter to change DC to AC. The inverter is a bigger deal than it first appears to be, because the inverter for a public utility must produce a very pure sine wave and that is much harder to do while still maintaining high conversion efficiency.

• The consumer that purchases a solar power generating system for home installation pays only a small fraction of its real cost, often as low as only 25%. That is because every sale is subsidized by direct payments of your tax dollars and by the government placing un-funded mandates on utility companies, requiring them to push the solar power "alternative". These unfunded mandates are re-paid by the rest of us in the form of higher utility bills.   [+]

Is there any use for solar power that makes sense?
Yes, solar power makes sense in those limited applications where the customer does not have convenient or economic access to the power grid, such as with remote country or mountain top homes. It is also useful for powering mobile or portable equipment such as utility, emergency, scientific devices, etc., where it is not otherwise feasible to hook to the power grid.

But other than those narrow exceptions, it makes no economic, engineering, ecological or practical sense to use solar power as a replacement for, or even as a compliment to, conventional power plants. Solar may have its' own specialty niche, but in no way does that rise to the level of an "alternative" to conventional power plants.

[harpseal]

I agree that there are some limited ways solar energy can be put to use. However, it is currently being sold (and funded by your tax dollars) as a serious competitor, alternative and compliment to conventional electrical generation. That's what I've got serious problems with and why I posted this thread. Conservatives need the info at their finger tips to discredit the disciples of solar electric power.

If solar power were to become economical by a reduction of cost of PV cells and increases in the efficency of any of the steps from cells to useful power they could then their use will naturally expand. At present their primary usage is for power where running power lines is cost prohibitive. That is in certain cases they do provide an economic benefit. As economies of scale and advances in efficency of any of the steps increase then they will become more economically sensible. They will not be a source for centralized power generation rather they would more likely be useful first in rural applications. For example a Farm may use them to provide power for a well pumping application. They are already used for some things like telecom relay towers.

In short I agree with your statement about the current applications of solar power but I further recognize that economies may increase the application of these technologies in the future. They will never become our primary means of power. Now a shed roof that is 10m by 10m provides 100 sq m given the fact that you have at present an output of 11 w/ sqm (I am presuming whrs since you have factored in night) that is 1100whrs per day from a building with a 100 sqm roof a little larger than some homes but within range. Now since an average home needs in the range of 5KWhrs to function solar needs a 500% increase in efficency to become a reasonable alternative for most homes.

Now teh place where this increase is most likely is in the efficency of the PV cells themselves. If the loss were down to say 50% then it might well be practical. No I have no idea how to get there but as i stated for some aplications PV's make sense and I do believe that market forces will tend to make PV's cheaper, more reliable, and more efficent.

[Boot Hill]

visualops says:   "...solar power devices will simply not keep being installed if they haven't proven cost effective.."

Incorrect. Tax subsidies hide almost the entire cost from the consumer. Please review this link from the article: Financial Incentives for Solar Energy

--Boot Hill

[DB]

Then I'm still getting screwed on my electric bill...

Currently it is claimed that large-scale solar electric energy generation costs run about 20 cents a kilowatt-hour.

Not competitive but improving (which I acknowledged in my first post).

I also said that if the costs of those $700 100 Watt panels fell to $50 in high volume it would be a good deal (as in cost effective and reasonably practical to use). Actually at $50 a panel it would be a really good deal.

[biblewonk]

Thanks for the intro Freeper bro!

[Boot Hill]

mtbopfuyn says:   "May I hazard a guess that you've never tried solar energy?."

I am an engineer. I've spent a life time in electronics and optics. I am thoroughly familiar with the technology and the economics of solar power.

--Boot Hill

[biblewonk]

Well at least from the power producer standpoint the truth is out on wind energy production, which I am certain has the same government subsidy as other forms of alternative energy. Wind can only be a backup or "alternative" due to its inefficiencies. It doesn't blow all the time. Seems to me it is 35 percent inefficient right out of the box at the point the wind blows, then throw in all the little stuff that the utopians want to overlook, and you have a horribly inefficient system that no one could would or should invest in if it wasn't being paid for by OPM. OPM is a myth, it is never just OPM it's everyones dollars, including the wealth and health of the government the people and the nation itself, and we let congress spend it like there is no tomorrow, and with precious little oversight, all at the whim of folks who think science is making stink bombs in high school.

Why do you use the term inefficient when you mean intermittent? Why are you so offended by a few million dollars in subsidy for wind power but care so little about the subsidies for all other forms of "conventional" power. The latest one I read about is 35 billion dollars for Black Lung benefits? Does this register with you at all?

[Boot Hill]

Consort asks:   "and what form of energy do you represent?"

Solar [grin]

--Boot Hill

[DB]

Is Moss Landing the plant near Salinas or Half Moon Bay (I forgot...)

As you saw from an earlier post I'm in SLO county.

[lawdude]

"...because peak power usage occurs at about the same time as peak power consumption."

Aren't those the same thing? Do you mean peak power output occurs...?

[DB]

Efficiency because if you need 1,000 watts continuously and the wind only blows 35% of the time then you have to generate nearly 2,900 watts during the time it blows. So your 2,900 watt generator only generates 1,000 watts on average over the long term (or 35% of its capacity).

[LN2Campy]

That efficiency % is disingenous at best: the largest "loss" of energy is atmospheric absorption. I would argue that since solar power is only collected once it has already passed through the atmosphere, this "loss"
really isn't a loss at all.

Considering the necessary military expenditures for protecting our access to overseas crude, the pittance in subsidies allocated to solar power is miniscule.

[cinFLA]

My AZ swamp cooler gave me much better performance than the hot water heater on the roof.

[ninenot]

we would need to cover the entire state of New Mexico

Make it California, and we have a deal.

[FreedomPoster]

Those things work great in the SW; they're next to useless in the SE.

[CGVet58]

bump and keep

[biblewonk]

Efficiency because if you need 1,000 watts continuously and the wind only blows 35% of the time then you have to generate nearly 2,900 watts during the time it blows. So your 2,900 watt generator only generates 1,000 watts on average over the long term (or 35% of its capacity).

I don't think you know what the term means. Efficiency pertains to the percentage of power in vs the work out. A car is not less efficient because some times it is not running. But anyway wind does have the intermittance problem. To many it is still preferable to use affordable renewable energy when it is available and save the coal and gas for later. Meanwhile, each month that we develop wind power it becomes more and more cost effective. They are expecting offshore wind farms to produce power at 2.5 cents per kwhr in the next 15 years.

Intel would never have gone from the 5 mhz 16 bit processor to the 2 ghz 64 bit processors without money to develop them. We can't hope to see clean renewable energy from wind become cost effective if we use every excuse not to support their development. I'm very excited to see GE and SHELL investing heavily in wind power. They know it is the coming thing.

[upcountryhorseman]

In addition to the inefficencies, there is the problem
of energy storage. If you don't have an existing power grid
to tie into, you must use batteries. This is only feasible
in a residential application.

[Sloth]

I'd prefer to just say "nuclear fission".

Absolutely. There's no other option so clean & affordable. We just need to change the name to make it less scary... Perhaps "hug fission" or "JonBenet fission."

[FreedomPoster]

>>In addition to the inefficencies, there is the problem of energy storage. If you don't have an existing power grid to tie into, you must use batteries.

Actually, hydro pumped storage is an alternative. It's done a couple places here in GA.

[kegler4]

Solar will certainly never provide all of our energy, but do we just ignore the possiblity of technology improvements in the future? We continue to pursue missile defense, which is even more of a joke than solar power at this point.