Western EcoSystems Technology, Inc., Laramie, Wyoming, United States of America.
Western EcoSystems Technology, Inc., Cheyenne, Wyoming, United States of America.
PLoS One. 2022 Apr 8;17(4):e0266500. doi: 10.1371/journal.pone.0266500. eCollection 2022.
Current research estimates hundreds of thousands of turbine-related bat fatalities in North America annually. In an effort to reduce impacts of wind energy production on bat populations, many facilities implement operational curtailment strategies that limit turbine blade rotation during conditions when nighttime wind speeds are low. Incorporating real-time bat activity data into wind speed-only curtailment (WOC) strategies may increase operational flexibility by allowing turbines to operate normally when bats are not present near turbines. We evaluated costs and benefits of implementing the Turbine Integrated Mortality Reduction (TIMR) system, an approach that informs a curtailment-triggering algorithm based on wind speed and real-time bat acoustic data, compared to a WOC strategy in which turbines were curtailed below 4.5 meters per second (m/s) at a wind energy facility in Fond Du Lac County, Wisconsin. TIMR is a proprietary system and we had no access to the acoustic data or bat call analysis software. Operational parameters for the TIMR system were set to allow curtailment at all wind speeds below 8.0 m/s during the study period when bats were acoustically detected. Overall, the TIMR system reduced fatalities by 75% compared to control turbines, while the WOC strategy reduced fatalities by 47%. An earlier analysis of the same TIMR data neglected to account for carcasses occurring outside the plot boundary and estimated an 84.5% fatality reduction due to the TIMR system. Over the study period, bat activity led to curtailment of TIMR turbines during 39.4% of nighttime hours compared to 31.0% of nighttime hours for WOC turbines, and revenue losses were approximately 280% as great for TIMR turbines as for turbines operated under the WOC strategy. The large cost difference between WOC and TIMR was driven by the 4.5 m/s versus 8.0 m/s wind speed thresholds for curtailment, but our study site has a relatively low average wind speed, which may also have contributed; other wind operators considering the TIMR system will need to consider their ability to absorb production losses in relation to their need to reduce bat fatality rates.
目前的研究估计，北美的风力涡轮机每年导致数十万只蝙蝠死亡。为了减少风力发电对蝙蝠种群的影响，许多设施实施了运营缩减策略，即在夜间风速较低时限制涡轮机叶片旋转。将实时蝙蝠活动数据纳入仅风速缩减（WOC）策略中，通过在蝙蝠不在涡轮机附近时允许涡轮机正常运行，可能会增加运营灵活性。我们评估了在威斯康星州丰迪拉克县的一个风力发电场实施涡轮机综合死亡率降低（TIMR）系统的成本和收益，该系统基于风速和实时蝙蝠声学数据为缩减触发算法提供信息，与 WOC 策略相比，该策略在风速低于 4.5 米/秒（m/s）时将涡轮机关闭。TIMR 是一个专有系统，我们无法访问声学数据或蝙蝠呼叫分析软件。在研究期间，当蝙蝠被声学检测到时，TIMR 系统的操作参数设置为允许在所有风速低于 8.0 m/s 的情况下进行缩减。总体而言，与对照涡轮机相比，TIMR 系统将死亡率降低了 75%，而 WOC 策略将死亡率降低了 47%。对同一 TIMR 数据的早期分析忽略了计算发生在绘图边界之外的尸体，并估计由于 TIMR 系统导致死亡率降低了 84.5%。在研究期间，与 WOC 涡轮机相比，TIMR 涡轮机在夜间有蝙蝠活动时的缩减时间占夜间总时间的 39.4%，而 WOC 涡轮机的缩减时间占夜间总时间的 31.0%，TIMR 涡轮机的收入损失大约是 WOC 策略下涡轮机的 280%。WOC 和 TIMR 之间的巨大成本差异是由缩减的 4.5 m/s 与 8.0 m/s 风速阈值驱动的，但我们的研究地点的平均风速相对较低，这也可能是造成这种情况的原因；其他考虑 TIMR 系统的风力运营商将需要考虑他们吸收生产损失的能力与其降低蝙蝠死亡率的需求之间的关系。
