According to a report released by the U.S. Department of Energy (DOE), Wind power is now the largest source of renewable energy in the U.S. Wind provides more than 9% of electricity nationwide, over 50% in Iowa and South Dakota, and over 30% in Kansas, Oklahoma, and North Dakota. Wind turbines continue to grow in size and power, so it’s not surprising that they have become a target for critics. Social media posts that have been widely shared have alleged that wind power is inefficient and unnecessarily expensive. For example, one Twitter post reads, “the turbine has to spin continually for 7 years just to replace the energy it took to manufacture.” See other similar posts here, here and here. We rate this claim as false. Wind turbines recoup the energy required to build them within a year of normal operation, according to researchers.
Jack Brouwer is a professor of mechanical & aerospace engineering at the University of California, Irvine. He is also the director of UCI’s Advanced Power and Energy Program and the National Fuel Cell Research Center.
I refute the claim that “wind power is inefficient and unnecessarily expensive.” Data regarding wind power costs has been published by many organizations, for example by the International Renewable Energy Association (IRENA) as presented below, which show that wind power costs have been dropping very significantly in the last decade and are becoming competitive with fossil fuel combustion power generation prices on an energy basis (note current prices for onshore wind less than $0.05/kWh and for offshore wind less than $0.10/kWh). And these prices are likely to continue to decline into the future as the market size and turbine sizes continue to increase. Regarding the inefficiency claim, wind turbines can convert wind energy into electricity at efficiencies in the range of 20-40%, but efficiency is an inconsequential metric that should not be used to determine the value of wind power since the input wind energy is renewable and available at zero cost, which is very different from the efficiency metric as applied to fuel generation for which fuel must be purchased.
Stephen C. Nolet, Principal Engineer and Senior Director, Innovation & Technology at TPI Composites, Inc. has this to say…
There are “notionally” many studies that have offered different conclusions (depending on the bias of the author). However, the consistent response I have seen which always contains a range of time (based upon turbine and siting conditions) report that the embodied energy of the installed turbine (which includes the entire energies in materials, transportation, erection and projected O&M over the life of the turbine) is returned in operation between 4 – 7 mo (120 to ~200 days).
“With proper maintenance, wind turbines should be expected to operate for 20 years or longer (industry projections these days are more like 30 years), which means that over their lifetime, wind turbines repay their energy debt many times over,” says Mark Bolinger, an engineer at Lawrence Berkeley National Laboratory. “Wind is one of the cheapest forms of electricity generation that exists today.”