Mortality due to collision with turbine blades might be a serious concern at wind farms where bird activity levels are high or threatened species use the airspace. Mitigation measures to prevent collision mortality might be necessary if collision risk is evaluated to be high in ornithological studies.
A common and effective mitigation practice is active turbine management through shut-down on demand. This practice minimizes both of collision mortality and energy production loss. The following three are needed to implement this measure:
- A reliable baseline bird survey
- Expert bird surveyors
- A protocol developed for the unique needs of the site
The protocol delineates the responsibilities of command desk and surveyors. It details the answers to the who, where, when, what and how much questions pertaining to shut-down events in very clear terms. Documentation and reporting is also described.
Bird surveyors must be present and actively scanning the site every day during daylight hours for any period / season of the year when risky bird passage might occur. Survey period for sites located along major bird migration routes would be spring and autumn while for sites where globally threatened species are residents it would be year-round.
Surveyors ensure that the turbines are paused whenever risky bird passage is detected. Turbine activity is cleared to resume as soon as risky passage is over. This simple yet effective solution prevents migrant and threatened species mortality.
The success of shut-down on demand implementation can be measured by routine carcass monitoring and mortality studies.
Command desk personnel is an integral partner in proper implementation. At the beginning of each season a briefing and applied drill session is held with the participation of all stakeholders. Various shut-down scenarios are simulated in order for the personnel to practice reaction times and test the turbine stop times. The drills significantly improve efficiency for the rest of the season.
In a shut-down event, the surveyors relay the turbine pause order to the command desk personnel via radio communications. Command desk personnel follow the required steps on SCADA systems to pause the turbines. Every shut-down event is documented by both parties in a detailed manner.
Site specific shut-down protocol is revised and improved based on the data collected and analysed from the event reports.
KAB Ecology is the trailblazing firm in Turkey for the first ever implementation of shut-down on demand at wind farms.