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Bigger, Cheaper Solar Cells
Phenombecile800 writes "First Solar, a start-up from Arizona, is making photovoltaic cells at a fraction of the usual cost. Their secret: increasing the light-catching area 'from postage-stamp to traffic-sign dimensions,' reducing the manufacturing time to 1/10th of the competition's, and thinning the active element to 1/100th the usual thickness over a glass substrate, which enables the production of large panels. IEEE Spectrum provides some technical details about the production process. 'Glass is placed on rollers and fed into the first chamber, where it is heated to 600 C. Then it is transferred into the second chamber, which is full of cadmium sulfide vapor, formed by heating solid CdS to 700 C. The vapor forms a submicrometer deposit on the glass as it moves through this cloud, after which a similar process in a third chamber adds a layer of micrometers-thick CdTe in about 40 seconds. Then a gust of nitrogen gas rapidly cools the panels to 300 C in a fourth chamber, strengthening the material so that it can withstand hail and high winds.'"
It's probably unanswerable, but I wonder how much energy it takes to make these cells, and how long it takes for them to offset that?
"And the meaning of words; when they cease to function; when will it start worrying you?"
Their secret: increasing the light-catching area 'from postage-stamp to traffic-sign dimensions,' reducing the manufacturing time to 1/10th of the competition's
So, what's the secret to their secret?
My Karma: ran over your Dogma
StrawberryFrog
What's a better use of oil, making persistent sources of energy, or driving to 7-11 for nachos?
Well, a smart idea would be to move all of our high tech manufacturing to the hottest deserts we have. You can build earth sheltered factories to save on A/C, cover the roof and surrounding area with solar panels for virtually unlimited electrical supply, bury some flywheel energy storage to keep necessities going at night. If solar panels turn out to be unsustainable, simpler thermal power plants could be used.
You have an endless supply of sand for glass and silicon. You make non-perishable goods that can be moved out slowly and efficiently (solar/thermal powered electric rail or whatever). To make it really sustainable you could use the same transportation to import recycled or recyclable plastics for the rest.
Our current answer is using fuel that's guaranteed to run out. We should shop direct for our energy.
Actually, the biggest portion of glass manufacturing is, of course, heat. You wouldn't want to use 10% efficient cells to produce electricity that goes directly to an electric resistance element to make that heat.
Instead, you'd want to build a solar furnace - using mirrors and lenses and such you can get 90% efficiency, and using panels even cheaper than this.
The trick would be the substantial start-up time in the mornings. Due to the heat levels involved, you'd be wasting a lot of energy each day heating the equipment up again.
So either you have to find a solution for this, or use natural gas or whatever during the night to keep production up. This isn't bad as long as you still get more energy out of the resultant panels, etc...
I don't read AC A human right
The biggest source of solar subsidy for homeowners in Arizona is the power companies themselves. They'll pay for roughly half of your installation. My guess is that this is just smart infrastructure investment for them-- you foot half the cost and handle the maintenance, but they know the panels aren't moving once they're installed.
What you need is a thermal storage system and good insulation of your hot gear. Since they're talking about using molten salt as well as other substances like hard pitch (incredibly high boiling point) as thermal storage to allow solar power plants to produce power over 24 hours, I'd say the solution to the problem is at hand.
And you're 100% correct that you should keep the solar power in thermal form. Thermal solar is much lower cost and you don't have the transformation losses that you mentioned. All you need is glass with aluminum/glass coatings for the mirrors along with an efficient thermal transfer/storage system and you're off to the races.
Forbes mentions that Mojave Desert real estate is becoming more valuable because many companies want to build solar facilities there.
It's not just solar farms that are sprouting up in the Mojave, wind farms are as well. Actually there's one wind farm that virtually sat there silent back when CA had those rolling blackouts because the transmission capability wasn't there.
Falcon
Should there be a Law?
Where I live, in Southern California, I believe SCE generates our electricity from oil and natural gas. Oil comes from oilfields.
You believe. Per SCE's site, it's "These resources include natural gas, a fossil fuel; falling water in hydroelectric plants; nuclear energy and renewable resources, like solar and wind."
A coal plant was shut down 3 years ago, due to failure to obtain new permits, rendered uneconomical due to increased pollution control requirements.
Oil is not listed.
Natural gas comes from oilfields and natural gas fields.
While NG does come from fields much like oil, it doesn't get shipped over here from the middle east. Production is domestic. Thus, engaging in wars overseas, for oil or not, won't have an effect on NG supplies.
The WSJ article you link to is talking about direct, overt government subsidies. Those aren't the subsidies I'm talking about.
Then which ones are you talking about? The ones where they aren't taxed like they should be for the environmental harm they cause? Or the portion of the military budget supposably spent to secure supplies?
I don't read AC A human right