RENEWABLE ENERGY:
A BETTER WAY
No single solution can meet our society's future energy needs. The solution instead will come from a family of diverse energy technologies that share one common thread--they do not deplete our natural resources or destroy our environment.
Renewable energy technologies tap into natural cycles and systems, turning the ever-present energy around us into usable forms. The movement of wind and water, the heat and light of the sun, steam trapped underground, the carbohydrates in plants--all are natural energy forms that can supply our needs in a clean, nonpolluting, and sustainable way.
FREQUENTLY ASKED QUESTION ABOUT RENEWABLE ENERGY
What happens when the sun doesn't shine or the wind doesn't blow?
Cloudy days and calm days make the power output from solar and wind power fluctuate. But no power plant is always producing power. Because of shutdowns for maintenance and fluctuations in power demand, a coal plant might generally produce only 60 percent of the power it could produce at full power if it were always turned on. Such a "capacity factor" for a wind turbine might be 30 percent, while that of solar power plants is around 20 percent.
When an intermittent source like wind or solar is part of a utility generation system, it is simply integrated with all of the other power plants. When renewable systems are used in remote sites, a set of batteries stores power for when the resource itself is unavailable.
If the sun and wind are free, why isn't renewable energy free?
Although the fuels are free, the equipment and labor needed to capture power from the sun, wind, and water are not. The costs are coming down, however, and with mass production, economies of scale will ensure even lower prices.
Are renewables really any more environmentally friendly than other energy sources?
Very much so. Renewables offer a number of improvements over coal, gasoline, oil, natural gas, and nuclear power. Solar, wind, and hydropower produce no direct air or water emissions. Biomass gives off carbon dioxide when burned, but only as much as it took from the atmosphere when it was growing. Other emissions from biomass are lower than those from coal or oil.
A complete comparison requires a look at the entire life-cycle of the energy source, from manufacturing and mining through use and disposal. When life-cycle impacts are considered, renewables fare even better. The environmental impacts of renewables are minor compared with the effects of a single coal-burning power plant.
If we grow crops for biomass energy, how will we produce enough food?
A drive through the Midwest may make you think that the entire country is planted in corn and soybeans. In fact, a large amount of land is not in use for food production. Erodible land, for example, is protected under the Conservation Reserve Program.
If farmers grew "energy crops" on Conservation Reserve land, they would provide erosion protection for the land and extra income for farmers. A 1993 study by UCS, Powering the Midwest, identified a huge potential for biomass in the Midwest -- even after excluding all land used for growing food.
CONTINUED ON NEXT PAGE -->Written by: Union of Concerned Scientists
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