Greenhouse gases produced over the lifetime of a wind turbine – including for its manufacturing and installation – are less than that of fossil-fuel based energy sources and most other renewables, a new study from the US shows. Only ocean energy (wave and tidal) and hydropower have lower emissions than wind.
As a clean, fuel-free source of energy, wind turbines obviously create energy without generating the damaging pollutants that result from burning coal, gas and other fossil fuels. But a charge often leveled by anti-wind energy groups is that the manufacture and erection of wind turbines creates emissions on a scale that belies the idea that wind power is clean.
The Life Cycle Assessment (LCA) study by the National Renewable Energy Laboratory shows that wind energy‘s lifecycle greenhouse gas emissions are a small percentage of those of fossil fuels, lower than nuclear, and even lower than nearly all other renewable energy resources. From cradle to grave, coal-fired electricity releases about 20 times more greenhouse gases per kilowatt-hour than wind or solar, for example (based on median estimates for each technology). See the study for further details.
The study takes into account all the stages in the life of an energy technology: upstream (raw materials extraction, construction materials manufacture, power plant construction); fuel cycle (resource extraction/production, processing/conversion, delivery to site); operation (combustion, maintenance, operations) and downstream (dismantling, decommissioning, disposal and recycling).
The NREL study uses different parameters to EWEA to calculate the amount of CO2 produced by a wind turbine over its lifetime. Even so, this study backs up information on the EWEA FAQ webpage which says ‘It takes a turbine just three to six months to produce the amount of energy that goes into its manufacture, installation, operation, maintenance and decommissioning after its 20-25 year lifetime. During its lifetime a wind turbine delivers up to 80 times more energy than is used in its production, maintenance and scrapping. Wind energy has the lowest ‘lifecycle emissions’ of all energy production technologies’.
By Tom Rowe, http://www.ewea.org/blog