June 16, 2014 – Writing in the International Journal of Sustainable Manufacturing, U.S. researchers conclude that—in terms of cumulative energy payback, or the time to produce the amount of energy required of production and installation—a wind turbine with a working life of 20 years will offer a net benefit within five to eight months after being brought online.

The researchers carried out an environmental life-cycle assessment of 2MW wind turbines slated for a large wind farm in the Pacific Northwest.

“All forms of energy generation require the conversion of natural resource inputs, which are attendant with environmental impacts and costs that must be quantified to make appropriate energy system development decisions,” explain Karl Haapala and Preedanood Prempreeda of Oregon State University, in Corvallis, who performed the study.

The pair carried out a life-cycle assessment (LCA) of 2MW wind turbines to identify the net environmental impact of the production and use of such devices for electricity production. An LCA takes into account sourcing of key raw materials (e.g. steel, copper, fiber glass, plastics, concrete), transport, manufacturing, installation of the turbine, ongoing maintenance through its anticipated two decades of useful life and, finally, the impacts of recycling and disposal at end-of-life.

Their analysis shows the vast majority of predicted environmental impacts would be caused by materials production and manufacturing processes. However, the team found the payback for the associated energy use is within about six months. It is likely that, even in a worst case scenario, lifetime energy requirements for each turbine will be subsumed by the first year of active use. Thus, for the 19 subsequent years, each turbine will, in effect, power over 500 households without consuming electricity generated using conventional energy sources.