Improved Model Helps Explore Environmental Impacts of Offshore Wind Farms
A three-dimensional climate model has been updated to better examine the environmental impacts of large-scale, offshore wind turbine deployment by DOE researchers at the MIT Joint Program on the Science and Policy of Global Change. Building on previous research suggesting that land-based wind turbines large enough to meet ~10% of predicted world energy needs in 2100 could cause localized surface warming, the updated model’s spatial resolution was increased and six additional simulations were modeled to address the potential environmental and intermittency issues for differing offshore installation areas and spatial densities. In contrast to the land-based results, the MIT researchers found that offshore wind turbine installations cause a local surface cooling effect, exceeding 1° K in the highest density case. This cooling is primarily due to the enhanced latent heat flux from the sea surface to the lower atmosphere, driven by an increase in turbulent mixing caused by the wind turbines. The study also found that the perturbation to global circulation caused by the large-scale deployment of offshore wind turbines is relatively small compared to the case of land-based installations. The study also demonstrated significant seasonal wind variations, highlighting an intermittency issue for potential power generating and distributing systems over several major offshore sites.
Wang, C., and R. G. Prinn. 2011. “Potential Climatic Impacts and Reliability of Large-Scale Offshore Wind Farms,” Environmental Research Letters 6(2), DOI:10.1088/1748-9326/6/2/025101.