Re-Assessment of the energy losses due to curtailment for the protection of bats

Site: Medium size wind farm in the state of Hessen, Germany

Method:

• Analysis of SCADA data of the wind turbines
• Comparison with model calculations
• Parametric studies

Results:

• The calculations with the model of aj determine the real energy losses very well.
• Too high values of the outside air temperature measured by the turbines lead to unnecessary shutdowns. The energy losses are thus signficantly higher.
• Some turbines show too low wind speeds. This also leads to unnecessarily increased shutdown periods and too high energy losses.
• The wake impact within the wind farm must be taken into account in the model calculations.
• The energy losses are much higher in years with low wind resource compared to high wind years.