Large-scale green wind and solar energy programs could conceivably become by far the nation's largest source of electricity within 20 years, according to the National Oceanic and Atmospheric Administration.

Speaking at a recent meeting of the American Association for the Advancement of Science, Sandy MacDonald, director of NOAA's Earth System Research Laboratory, said that solar and wind power could provide 70 percent of the electricity needs of the Lower 48 states by 2030, with fossil fuels chipping in a relatively measly 15 percent. (Hydroelectric and nuclear power would provide the rest.)

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The projection is the result of work by ESRL's Renewable Energy study, which took 16 billion pieces of weather data, devised a program to filter out unlikely sites for solar arrays and wind farms (such as national parks and urban areas), and concluded, predictably, that the middle of the continent had the best wind resources and the desert southwest was the best location for solar power production.

So far, so obvious. But the NOAA program went one step further, developing in principle a means to make any renewable-energy grid as efficient and thus cost-effective as possible, by balancing production and demand. For example, peak U.S. power consumption is in August, when air conditioners are on full blast. That, alas, is when solar production falls off in Arizona because of seasonal cloudy weather, but it matches perfectly with available sunshine in California. Development of a "smart" grid that can easily respond to such changes in demand — ideally one of about 5 million square kilometers — would be key, said MacDonald, according to the Vancouver Sun.

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Germany already derives 20 percent of its energy from wind, solar, biomass and geothermal sources, and one of the principal architects of that country's push into renewable energy has stated that it could potentially be 100 percent dependent on renewables by 2030. In an interview with RenewEconomy, the Green Party's Hans-Josef Fell argued that "perhaps it could be 30-40 percent solar, 40-50 percent from wind. Then comes the task to balance high fluctuations from wind and solar as the weather changes. This balancing is not possible with baseload, because you cannot switch them on and off very fast. Gas power stations can switch on and off very fast –- but natural gas brings emissions in carbon, and we are dependent on Russian natural gas. We have to learn how to do without it."


The sun sets behind a power line near Laatzen, Germany, Feb. 6, 2012. Due to growth in wind and sun energy supply, Germany barely suffers from power outages during the extremely cold winter. According to a representative of the German Ministry of the Environment, the increase in wind and solar power pays off. The four major power suppliers already assured consumers that Germany will not suffer outages during the cold weather.

Photo Credit:

Julian Stratenschulte, Corbis.