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Here is what the acolytes of solar power don't want you to know...
self
| July 15, 2003
| Boot Hill
Posted on 07/15/2003 3:16:56 AM PDT by 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.
TOPICS: Business/Economy; Editorial; Government; Technical; Your Opinion/Questions
KEYWORDS: alternativepower; electricpower; energy; environmentalism; fresnellens; photovoltaiccells; photovoltaics; renewablepower; solar; solarcells; solarpower
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To: Boot Hill
What about Bio-diesel. It seems to me that a great way to remove our dependence on foriegn oil would be to power cars with fuel made from vegetable oil. We have more than enough farm land to produce the vegetable oil, could be done by the farmers that are being paid to not produce. It's much more environmentally friendly, and diesels are much more efficient if the engine is kept small (compacts, not trucks & SUV's) all we have to do is figure out how to make a decent deisel engine (send spys to the vw plant?!?)
What am I overlooking, because this seems too simple to me so someone else much smarter than me should have worked it out some time ago....
41
posted on
07/15/2003 5:05:14 AM PDT
by
logic
("all that is required for evil to triumph, is for good men to do nothing")
To: DB
DB contends: "
You also show the plants capital expenses to build the plant but not the actual fuel costs over the life of the plant."
Incorrect, I covered that in the third paragraph of "Here is an example" and the interest costs of the very expensive solar power plants would exceed the actual fuel costs over the life of the plant. The interest costs of a 30 year, 10 billion dollar loan at 5.3% would be $9 billion dollars greater for a 1000 MW solar plant than for a conventional power plant. The cost of the natural gas for the conventional plant during that same 30 year period would be $8.9 billion dollars. This presumes $1/W for conventional and $10/W for solar. The real cost of a solar power plant would be greater than the $10/W figure I quoted and conventional plants are closer to $0.75/W.
--Boot Hill
To: Boot Hill
Sheer crapola. I haven't seen so may lies and half-truths in one place since Clinton wagged his finger.
To: logic
I've heard it sure smells good. Like
French Freedom fries.
But, it is hard on fuel systems. You know the golden crud you get on oven utensils after greasing them and baking something? Which is difficult to scrub off? That's what happens to veggie oil in engines.
To: Boot Hill
So you get them within hollering distance. That's actually better than I'd expect.
To: logic
On my last 'pooter, before it crashed I had bookmarked a study that one college in the midwest did on a 12 valve Cummins diesel engine, these power 3/4 and 1 ton pickups as well as busses / 45 foot boats........anyway, they ran this engine for months on end on pure veg oil, only stopping forcrank case oil changes etc. and discovered no additional wear / tear versus running on conventional diesel fuel.
It is entirely do-able. The biggest stumbling block is that veg oil gels up and cakes up in sub 40 degree weather.
If you do a web search you'll discover there's quite a few home hobbyists running 100% veg oil in their diesels.....not just the 90 /10 % diesel / bio fuel mixture.
46
posted on
07/15/2003 5:21:23 AM PDT
by
taxed2death
(A few billion here, a few trillion there...we're all friends right?)
To: logic
logic asks: "
What about Bio-diesel?"
Transportation accounts for the consumption of about 26 million, billion BTU's annually. Does it sound feasible to extract that much from our nation's soils? (Just a question, not a statement.)
--Boot Hill
To: Boot Hill
Let's do it! What else is New Mexico good for, anyway?
48
posted on
07/15/2003 5:25:28 AM PDT
by
Growler
To: Boot Hill
To: Wonder Warthog
Don't be shy, WW...
--Boot Hill
To: Boot Hill
Here's a twist on solar power I read recently (I think it was in Discover).
Sorry, I don't have the referenced material handy, so forgive the vague details.
There's some guy with a long track record of successful ventures (not a nut) who says that silicon is not the way to pursue solar power. He has develped working prototypes of focused multi-mirror Stirling engine powered generators. These apparently are self-contained critters about 9 to 12 feet across. He is working to refine the technology and make them yet smaller. Wish I could give you specs on output, etc. The proto-types are pretty expensive, but as with most new technology it will become very affordable once you stop building each one from scratch and put into mass production.
I'm not a scientist but the whole thing sounded very doable. And while Discover isn't a peer-review type publication, they don't print trash science either.
51
posted on
07/15/2003 5:34:03 AM PDT
by
Lee'sGhost
(Crom!)
To: The Red Zone
It is actually far worse than that. I wanted to be as fair as possible with the cost comparison and cut solar some pretty big breaks with those figures.
--Boot Hill
To: The Red Zone
There is a process where lots of oil, small amount of methanol and a tiny amount of something else (Lye? it's in the book, just can't remember yet. just starting my latte!) that produces a substance that is almost exactly diesel fuel and doesn't have that 'caking' problem. However it is hard on rubber fuel lines, they must be replaced with synthetic rubber (modern diesels already have this from the factory so no upgrade needed)
Or you can heat the pure oil and then run it directly into the engine without problems but you have to switch back to diesel fuel for a couple minutes to purge the injectors before shutdown and when starting. That would require significant 're-engineering.' Just the sort of thing that gets me excited, constantly tinkering with something so I can be late for work every third day or so :) (does that make me a masochist or is there something else required?)
I am blaming my cat for all my errors too, just because he's at home and I'm at work is irrelevant! It's the thought that counts right?
53
posted on
07/15/2003 5:38:36 AM PDT
by
logic
("all that is required for evil to triumph, is for good men to do nothing")
To: Boot Hill
So you're saying that natural gas costs are 3.4 cents a kilowatt-hour?
Why am I paying about 12+ cents a kilowatt-hour?
54
posted on
07/15/2003 5:40:20 AM PDT
by
DB
(©)
To: Radioactive
>>Just say -- COAL.
I'd prefer to just say "nuclear fission". It releases a lot less radioactivity into the general environment, not to mention all the other pollutants. And it can be done very cost effectively.
55
posted on
07/15/2003 5:40:28 AM PDT
by
FreedomPoster
(this space intentionally blank)
To: Growler
They have hot air balloon races, Sandia, Los Alamos, real interesting geology, Trinity site...
But on the other hand, New Mexico also is home to one of Ted Turner's bigger ranches.
--Boot Hill
To: Radioactive
Why would I say that?
--Boot Hill
To: goldstategop
[I]t could offer clean energy . .
Actually, no. It might be cleaner than other sources, but there are some pretty toxic processes involved in making solar cells. When one considers the environmental cost of making the cells (takes fuel, and mining for materials, etc.) and eventual disposal of the cells they are far from clean. Think of all the lead in car batteries. Yes, the materials could be reclaimed, but that just doubles the processing on already-toxic materials, and takes yet more fuel.
It's analogous to electric cars, which don't burn any gasoline as they hum along but require more total fuel to be used than gasoline cars, since conversion and transmission from the power plants is less efficient than burning the fuel at the point of use. Only by ignoring the upstream cost (in the case of electric cars, the generation of the power at the plant; in the case of solar cells, the environmental impact of producing the cells) do they make sense.
Let the marketplace decide. If it turns out to be cost effective, then people will use it. If not (and subsidies don't count) then they won't. The only 'bad' answer is forcing a false answer. And among the false ones is the claim that solar power is truly clean.
58
posted on
07/15/2003 5:43:16 AM PDT
by
Gorjus
To: DB
That's a fuel cost only. You have to build, finance, and maintain a powerplant to burn the gas, a transmission and distribution system to get the electricity to your house, pay for overhead, etc. Also, as a residential customer, you're locked in, unlike many large industrial customers, so you don't exactly get the best rate.
59
posted on
07/15/2003 5:43:40 AM PDT
by
FreedomPoster
(this space intentionally blank)
To: DB
Because the stockholders would be offended if the power company gave away the power with out profit.
--Boot Hill
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