GRAND SOLAR PLAN FROM SCI-AM

This ambitious plan for powering the U.S. on solar energy is entirely sensible. It includes consideration of all relevant infrastructure, including vast generating plants, storage facilities to beat solar energy’s notorious intermittency and new transmission to carry the electricity across the nation.

From the article: “The technology is ready…We project that this energy could be sold to consumers at rates equivalent to today’s rates for conventional power sources, about five cents per kilowatt-hour (kWh). If wind, biomass and geothermal sources were also developed, renewable energy could provide 100 percent of the nation’s electricity and 90 percent of its energy by 2100.”

The only unknown is how to elect leaders with the vision to make the plan happen.

There is ample solar photovoltaic potential. (click to enlarge)

A Solar Grand Plan; By 2050 solar power could end U.S. dependence on foreign oil and slash greenhouse gas emissions
Ken Zweibel, James Mason and Vasilis Fthenakis, December 16, 2007 (Scientific American)

WHO
Scientific American (Sci-Am), one of the world’s premier science magazines

WHAT
Sci-Am puts forward a concrete program by which the U.S. could generate 69% of its electricity and 35% of its total energy from solar by 2050.

WHEN
- The plan would cost $400 billion over 40 years.
- In 2050, CO2 levels would be 62% below 2005 levels.
- The ramp-up in solar energy production would come in stages as costs go down and infrastructure expands.
- Stage One would run through 2020 and see a buildup to 84 gigawatts in the southwest and south. New transmission would also be built.
- Stage Two goes thru 2050, completing the buildup of infrastructure.
- 3,000,000 would be created by the plan.
- The article discuses projections beyond 2050.

There is ample solar thermal potential. (click to enlarge)

WHERE
Solar photovoltaic and solar thermal plants would be built in the southwest, where open land and sunlight are available.

WHY
- The plan assumes 30,000 square miles of photovoltaic arrays producing 3,000 gigawatts of electricity.
- Photovoltaic efficiency must be raised to 14%. Sci-Am identifies cadmium telluride thin film as the likely material to meet this need.
- 16 hours of solar energy storage would be through using excess electricity generated during sunlight hours to compress air that could be released to generate electricity when there was inadequate sunlight.
- Solar thermal plants (also known as concentrating solar) use arrays of parabolic mirrors to heat hot fluids that boil water to generate steam that drives turbines.
- High-voltage direct current (HVDC) power transmission would be constructed to deliver electricity from the southwestern solar fields to the national grid.
- Solar cell materials constraints are diminishing and solar cell materials are expected to be recyclable.

There are already solar arrays of the type described here. The only thing lacking is the commitment. (click to enlarge)

QUOTES
- From the article: “That investment is substantial, but the payoff is greater. Solar plants consume little or no fuel, saving billions of dollars year after year. The infrastructure would displace 300 large coal-fired power plants and 300 more large natural gas plants and all the fuels they consume. The plan would effectively eliminate all imported oil, fundamentally cutting U.S. trade deficits and easing political tension in the Middle East and elsewhere. Because solar technologies are almost pollution-free, the plan would also reduce greenhouse gas emissions…”
- From the article: “The greatest obstacle to implementing a renewable U.S. energy system is not technology or money, however. It is the lack of public awareness that solar power is a practical alternative—and one that can fuel transportation as well. Forward-looking thinkers should try to inspire U.S. citizens, and their political and scientific leaders, about solar power’s incredible potential. Once Americans realize that potential, we believe the desire for energy self-sufficiency and the need to reduce carbon dioxide emissions will prompt them to adopt a national solar plan”