Bats and wind power

Existing literature indicates that there are 25 to 28 species of bats in Kazakhstan, five of which are listed in Kazakhstan’s Red Book.  Sixteen of these species have been described only in Turkestan, a region in the country’s south, mainly in mountain biotopes. Bats are very little studied in Kazakhstan, with little or no recent or even past information on many species. What research exists is sporadic and fragmentary. There is no data on species abundance or population dynamics, migration routes, or high-density bat habitats for many species across most of the country. Without a better understanding of bat ecology, it is difficult to identify which species and population groups face threats, including from wind power, in the country.

In addition to expanding general bat research in Kazakhstan, it is essential to conduct pre-approval baseline studies in areas targeted for wind power development. Are bats present in the proposed area? Where do they roost? Does the species demonstrate any activity that makes it more likely to be threatened by wind power? Is the species known to be migratory? If the species is found outside of Kazakhstan, what are the known impacts on the species near other wind power plants?

Fortunately, wind energy site developers and operators have available several strategies and mitigation measures to reduce bat fatalities and long-term impacts on bat populations caused by wind power. Although the issues differ slightly in birds, many of the solutions are the same.

Siting and Monitoring. A critical first step is to avoid developing wind farms in areas known to be of high bat value and along bat migration and commuting corridors. Sites are often selected based on access to the transmission grid, local regulations, and land rental rates, without concern for whether ecologically sensitive habitats are affected. Siting guidance is often based on best available information, which can be limited in areas where wind energy is expanding. Once the wind farm is operational, operators should use a combination of monitoring approaches to assess the wind farm’s impact on bats and to help develop strategies to minimize bats’ interactions with turbines.

Curtailment. Operators can slow down or stop the rotation of a wind turbine’s blades when bats are present or expected to be present, allowing bats to navigate around the turbine’s blades without risk of collision. Execution of this strategy, known as curtailment, is dependent on time of year and wind speed. Data collected on bat activity, behavior, and mortality indicates that turbines pose the greatest risk to bats during low wind speed conditions, typically between late summer and early fall. The tradeoffs to curtailing wind turbines are that it results in a loss of power generation and may not serve as an effective strategy for all wind energy sites or for all bat species. As a workaround, wind farm operators adopt an approach known as “smart curtailment,” which incorporates additional data (for example, temperature, wind direction, or bat activity) to determine whether a turbine should be curtailed.

Establishing and Enforcing Legal Frameworks. Globally, measures to protect bats from the impacts of wind energy developments are mostly implemented in countries with strong legal protections for bats. Unfortunately, most countries, especially in emerging markets, lack legal frameworks and voluntary compliance is problematic. The United Nations Environment Program’s (UNEP) Convention on the Conservation of Migratory Species of Wild Animals covers many bat species but has not proven effective in resolving the conflict between wind energy production and bat conservation.