Policy Documents

Why Wind and Solar Energy Can’t Replace Traditional Power Systems

March 7, 2013

Wind and solar energy are dilute, intermittent, and more costly than traditional hydrocarbon energy sources. After atmospheric absorption and system losses, only a single 100-watt bulb can be powered from a square meter of solar cells, and this only at midday on a cloudless day.  Wind towers must be spaced about 140 meters apart to capture energy from the wind.  As a result, solar requires 75 to 100 times the land and wind requires 150 to 250 times the land of traditional power sources.

Solar systems don’t output energy at night or at low angles of incoming sunlight.  Wind systems provide rated output less than 30% of the time and this output varies chaotically. Traditional gas or coal power plants must be running as an active backup to maintain continuity of electricity supply.  Like a car driving in stop-and-go conditions, installation of a wind farm converts the power system into a stop-and-go electrical system.  In measured real world conditions, combined wind and hydrocarbon systems use more fuel, output more sulfur and nitrogen oxides, and emit more carbon dioxide than hydrocarbon-only electrical systems.

Total cost estimates show that wind and solar systems are significantly more costly than hydrocarbon energy sources.  Since wind requires an active backup hydrocarbon facility, wind can only replace some of the variable cost of a coal or gas plant.  Department of Energy 2011 estimates place the variable cost of coal at 3 cents per kW-hr and gas at 5 cents per kW-hr, compared to 9 cents for on-shore wind and 24 cents for offshore wind.  Solar costs are 20 to 30 cents per kW-hr.