Posters

Abstract

The improved competitiveness of wind energy means that state subsidy programmes with fixed feed-in tariffs could soon be a thing of the past. PPAs and direct marketing of wind power are gaining relevance for the funding of wind projects and lifetime extension decisions. In both cases, the current prices on the power exchange are of great importance. This calls into question the conventional operating strategy of wind turbines. If remuneration is based on proceeds from the power exchange, it makes sense to align the operating strategy with price fluctuations. How should such operating strategies be designed? What impact does this have on the profitability of wind farm projects from the owner's point of view? With the help of a case study, this work uses economic criteria to evaluate if turbines should operate or not depending on wind conditions and electricity prices. The results of the case study indicate that it can make sense to switch off the turbines in economically unfavourable situations. Lost low revenues in damage-intensive wind conditions are recovered through the revenues over a significantly extended lifetime of the turbines, and the project's overall profit and energy yield increase considerably. A wind farm with 20 turbines and a total nominal capacity of 67 MW is considered in the study. The simulated wind farm is located at a fictitious nearshore site in northern Germany. Simple operating strategies are examined, in which the decision to switch on and off depends solely on the electricity price, as well as more complex strategies, in which the price and wind conditions are taken into account. Using a simple, price-dependent strategy, the equivalent annual annuity increases from 161k € to 591k € when turbines are put into power production at non-negative prices or at a minimum price of 20 €/MWh. The turbines' lifetime and cumulated energy yield are increased from 20.7 to 25.5 years and from 5.96 TWh to 6.06 TWh, respectively. It is even more economical to take wind conditions into account when deciding whether or not to run the turbines. Using an optimised operating strategy that is based on electricity price, mean wind speed and turbulence intensity raises equivalent annual annuity to 953k € and lifetime to 30.4 years - leading to an overall energy yield of 7.27 TWh.