Producing electricity from wind reduces CO2 emissions, air pollution, and water use relative to fossil fuels. The CO2 offsets from wind energy are a key reason for its support and use in the decarbonization of electricity production. Here we summarize the results of a literature review focused on the offsets wind energy generates relative to fossil fuels. We first describe estimates of offsets for greenhouse gases (GHGs), air pollution, and water use. Second, we summarize the role wind energy plays in both forecasts and scenarios of world energy futures. We use this information to determine how large of a role wind energy will play, globally, in reducing GHG’s. Third, we use the concept of ecological endpoints, to frame how offsets from wind energy relative to fossil fuels can result in benefits. Ecological endpoints are measurable biophysical quantities such as species populations. An offset becomes a benefit if the ecological endpoint shows a measurable positive response to the offset. For example, reduced air pollution relates to reduced asthma rates, which is a measurable benefit to humans.
Results/Conclusions
Estimates of offsets vary widely (e.g. coal vs wind: 240-996 gCO2e/kWh) and depend on the types and number of fossil fuel power plants wind energy displaces. Offset estimates are used in simulations to predict declines in GHG and other emissions in scenarios and forecasts of regional, national, and global energy futures. The estimated offsets from wind energy vary depending on levels of assumed energy efficiency, the role of other renewables, and the level of global warming the scenario allows. Our current understanding of the benefits of wind energy to species is quite general. For example, wind energy produces less GHGs and many studies show global warming negatively affects species; therefore wind energy, by offsetting GHGs, will benefit species. This argument likely holds, but we found no studies directly linking offsets from wind energy to species status and trend. Ecologists could follow examples from human health research and used linked models to simulate the effects of wind energy offsets on particular ecological endpoints. We provide examples of how models could be linked to determine specific benefits of wind energy to species, including modeled relationships between GHG offsets, warming trends, and species extinctions.