Efficiency of wind power production and its determinants

•We examine efficiency of wind energy production in 19 wind turbines across Germany.•We propose an alternative method to construct power curves for wind turbines.•Using non-convex efficiency analysis methods, we quantify production losses.•We explain electricity losses via bias-corrected truncated regression.•Electricity losses amount to 27% of the maximal producible electricity.

This article examines the efficiency of wind energy production. Using non-convex efficiency analysis, we quantify production losses for 19 wind turbines in four wind parks across Germany. In a second stage regression, we adapt the linear regression results of Kneip, Simar, and Wilson (2015) to explain electricity losses by means of a bias-corrected truncated regression analysis. The results show that electricity losses amount to 27% of the maximal producible electricity. Most of these losses are from changing wind conditions, while 6% are from turbine errors.