The Clean Energy Path Renewable Options

clean energy pathIn 2006, 2,454 megawatts of new wind-generating capacity was added to the U.S. grid.

Looking forward, the U.S. government’s Energy Information Administration sees no great breakthrough for renewable sources of electrical power in the next 23 years. According to its 2007 outlook report, “Oil, coal and natural gas still are projected to provide roughly the same 86 percent share of the total U.S. primary energy supply in 2030 that they did in 2005.”

Coal, the federal experts think, will still be providing 57 percent of America’s electricity generation in 2030, and despite federal subsidies, the projection actually sees the nuke share declining by 2030, from 19 percent in 2005 to 15 percent in 2030.

The feds see only a modest gain in wind power, from 0.4 percent of total generation to 0.9 percent in 2030. Geothermal will stand still at 0.4 percent, as will municipal solid waste technology (trash to energy) at 0.5 percent. Photovoltaic solar will see modest gains—to a whopping 0.1 percent of the grid.

If these projections prove accurate, our planet will be awash in global warming gasses by 2030 and the world will soar past the 500 to 550 parts per million of carbon dioxide in the atmosphere that many scientists see as the catastrophic tipping point. But there’s still hope.

According to climate expert Dr. James Hansen of the National Aeronautics and Space Administration (NASA), “there is tremendous potential in energy efficiency and renewable energies, including solar power, wind energy, biofuels and geothermal.”

The Union of Concerned Scientists adds, “The government should adopt policies that maximize energy efficiency and conservation, increase the use of renewable energy resources, and eliminate barriers to existing technologies.”

The Bush Administration has not heeded this advice, but the renewable share is growing anyway. In 2006, some 2,454 megawatts of new wind-generating capacity was added to the U.S. grid with a $4 billion investment, says the American Wind Energy Association (AWEA). That’s a 27 percent increase in installed capacity and makes wind the largest renewable. Randy Swisher, AWEA executive director says, “Wind power is now one of the largest sources of new power generation in the U.S., and an essential element of the climate change solution.”

Just one nuke can equal all the 2,400 megawatts of new wind. But most new wind installations are large-scale wind “farms” with hundreds of turbines. The largest U.S. wind farm, in Texas, generates 736 megawatts of electricity. If we find room for a million two-megawatt turbines, we could produce hydrogen for millions of fuel-cell vehicles.

clean energy path

Sunlight is not only the most plentiful energy resource on Earth, it’s also one of the most versatile, converting readily to electricity, fuel and heat.

The photovoltaic industry addresses the capacity issue with so-called concentrating solar power installations (see “Big is Beautiful,” Currents, May/June 2007) that can be scaled into the hundreds of megawatts. George Crabtree, a senior scientist at the federal Argonne National Laboratories points out, “Sunlight is not only the most plentiful energy resource on Earth, it’s also one of the most versatile, converting readily to electricity, fuel and heat. The challenge is to raise its conversion efficiency.”

Crabtree and other scientists see opportunities to ramp up photovoltaic electricity production and efficiency through the use of new, cheaper materials, including films, dyes and organics. The American Solar Energy Association’s “Tackling Climate Change” report foresees pathways to both a 60 and an 80 percent carbon reduction by 2030 through energy efficiency and renewables. “Renewable energy [could] provide approximately 40 percent of the U.S. electric energy need projected for 2030,” the report says. Wind could provide 20 percent of U.S. electricity by 2030 and account for 15 percent of emissions reductions.

Biomass can be burned to generate electricity, offsetting huge carbon emissions, and biofuels (made from corn, agricultural residue and energy crops) could offset 58 million metric tons of carbon emissions per year by 2030.

The U.S. geothermal resource is actually far greater than total U.S. energy demand. The trick is recovering it in an economically viable manner. Unlike oil, geothermal is not necessarily concentrated in large, easily accessible reservoirs; considerable research has to be done to locate “hot spots” and recover the heat in commercial quantities. Geothermal plants release carbon dioxide, but far less than do coal, petroleum or natural gas production, and technological improvements have improved the picture.

The bottom line is that there exist eminently feasible alternatives to the Energy Information Administration’s highly pessimistic scenario.