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Solar Power Play
dpilgrim writes "While American power companies continue to chase vanishing oil reserves, the Japanese are once again a step ahead in innovation. Reuters is carrying this story about Sharp's new manucfacturing plant in the U.S. Sharp will begin manufacturing solar batteries stateside, and expects more than half its solar battery sales to be in the U.S. by 2004. Looks like a good use for that south-facing hillside on my property."
Photovoltaic systems still have a long way to go to become economical enough to compete with more conventional methods.
You get about 100 watts of solar radiation per square foot (perpendicular to the sun's rays). Current commercial PV cells are, at best, 15% efficient.. so now you have 15 watts of electricity per square foot.
A conventional powerplants generate roughly 500-1000 Megawatts each. Doing the math, you'ld need well over 32 million square feet of collection area to match that... roughly 765 acres of active surface. PV arrays can't be packed together either, because they would cast shadows on eachother... so the actual real-estate required would be 4 or 5 times that!
Even if the PV cells were *free*, the cost of installation, service, and the land itself would be astronomical! There's no way a solar farm could pay for itself.
Nobody is going to stop burning coal and oil anytime soon (unless they run out!)
Not to say PV cells don't have their uses, of course. Cheap PV panels can certaintly help ease the energy budget!
=Smidge=
My guess is that they are referring to a 3kW cell array. The ROI would be primarily a factor of how much power you use during daylight hours.
Without the tax incentives, it would be hard to see a 10-year simple payback, unless there are significant costs associated with hooking up to the power grid (namely distance).
Compared to a 3kW diesel generator... it has an ROI. Compared to $0.10/kWh... not yet!
That just is not true. Lead acid batteries are completely recycleable and most places in the USA REQUIRE them to be recycled when disposed of.
Solar panels are typically guaranteed for 20-30 years, and generally are productive for much beyond that. I have seen no evidence to indicate there is any particularly probelms with disposal afterwards.
Home Power Magazine has some references to studies on teh energy, environmental, and financial aspects of solar panel production showing that these types of statements, while worth investigating, are not significant problems.
Now as for me, I am pretty pro-nuke, but distributed solar is certainly a good way to go. Of course the best choice would be to not waste the energy in the first place - you know, install some compact flourescent and LED lights around the house, and turn down the AC once in a while...