Web Date: June 16, 2009
Renewable Electricity Expansion
Based on current rates of growth and available technologies, renewable energy—solar, wind, geothermal, and biomass—could provide 10% of U.S. electricity by 2020, according to a National Research Council report released June 15.
However, these sources of non-hydroelectric power generate less than 2.5% of U.S. electricity today, and under a business-as-usual scenario, they would reach only 8% of U.S. need by 2030, says the report. However, looking just at wind, recently applied consistent and aggressive policies to encourage wind's development have put this source of renewable energy on a growth curve to reach 8% by 2020, says K. John Holmes, who is the NRC staff director for this study.
Explaining the committee's approach, Holmes says, "The committee assumed an aggressive but achievable scenario. That means that a 10% share by 2020 and 20% by 2035 for non-hydro renewable energy sources seems within the nation's reach."
But to achieve these rates, the report says, policies should be in place to encourage advanced technologies, more financial investments, and greater deployment of renewable sources of electricity.
The report primarily concentrated on wind and solar and noted that these two sources of renewable energy offer larger total energy and electricity potential in the near term than do the others. It notes that solar power has the potential to provide several thousand fold more electricity than the nation currently needs; land-based wind turbines could provide 10% to 20% of national electricity demand based only on land-based installations.
However, to reach a 20% level would require $100 billion in new investments and 100,000 wind turbines, the report says, relying on Department of Energy data. On the other hand, the report says 140,000 new jobs would be created and 20% of carbon dioxide emissions that are currently generated by the electricity sector would be eliminated.
The report's authors, a mix of academics and industry executives, believe that to get beyond 20%, however, will require major scientific advances and will change the way the U.S. generates, transmits, and uses electricity.
Holmes stresses that a "fundamentally different electricity system" will be needed. Advances would include a much improved long-distance electricity transmission system to move electricity around the nation, an intelligent and two-way electric grid, and much better technologies to store electricity at widely distributed sites. The report singles out solutions such as co-siting wind and natural gas or wind and solar generating facilities to complement and make up for the generation variability of generation sources that depend on sunshine and wind.
Expansion of renewables will also have many environmental and local impacts, both positive and negative. For instance, while fewer emissions of a host of pollutants, such as mercury, sulfur dioxide, and CO2, would result from wind and solar energy, both require significant area for installations.
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