Solar possibilities
AIDG blog today has a short link to SciAm’s story on solar energy in the US.
In an extensive article, the writers argue that in 40 years, solar energy could provide more than half of needed US electricity. But, it’s not without cost.
To provide electricity at six cents per kWh by 2020, cadmium telluride modules would have to convert electricity with 14 percent efficiency, and systems would have to be installed at $1.20 per watt of capacity. Current modules have 10 percent efficiency and an installed system cost of about $4 per watt. Progress is clearly needed, but the technology is advancing quickly; commercial efficiencies have risen from 9 to 10 percent in the past 12 months.
They suggest dedicating over 30.000 square miles of land to solar cells, an area they say is “less than that needed for a coal-powered plant when factoring in land for coal mining.” Energy would be stored during night and cloudy days by pressurizing air or using the molten salt that Solar Reserve is pioneering.
However, their plan calls for significant subsidies, over 400 billion through 2050.