Reducing Bird Mortality Around Wind Turbines
As the harnessing of wind power continues to proliferate, the concern of what it might mean for wildlife is an important question. While the prospect of sustainable energy is obviously appealing, many wildlife advocates have noted that wind turbines can result in bird deaths. There is some debate as to just how much wind turbines result in bird mortality, and how that mortality might compare to other forms of energy production, but the data is not as robust as we would like. There is a range of strategies that can be employed to reduce avian mortality around wind turbines, from “curtailing (turning off) turbine operation during certain periods, …spacing the wind turbines at an optimal level, using tubular towers instead of lattice towers to reduce perching, …and painting turbine blades to make them more visible.”
This paper examines the issue of bird mortality around wind turbines and analyzes the strategy of curtailing wind power operations from the perspective of costs and benefits. Using wind operations in Cape Cod as a case study, the researchers collected hourly data on bird observations, wind speeds, and electricity price for a single month to make their calculations. They noted that there were certain times of day that would be best, but that “partial curtailment of turbines can be achieved in two ways – either curtail 20% of all turbines in the wind farm for a full 1hr period or curtail all turbines for 12 min during the hour.” They also note that a recent “valuation study” estimates that each bird saved costs about $42 in lost power generation, but that that cost would decline “once we consider the entire year and multiple species, to the point where it may be a reasonable strategy, particularly for highly-endangered birds.”
For wildlife and bird advocates, this study is an encouraging gesture towards making wind power more sustainable for everyone. The emphasis of this research is on costs vs. benefits, which may irk some advocates, but such calculations could also be used to protect certain threatened species of birds, and possibly to advocate for bird safety in future wind turbine designs.