Economic Benefit of Combining Wave and Wind Power Productions in Day-Ahead Electricity Markets

There is usually a cost associated to the integration of non-fully predictable renewables in electricity markets. This cost, named balancing cost, covers the difference between the bid to the dayahead electricity market and the actual power produced. The objective of the paper is comparing the balancing costs of a diversified system including wind and wave power productions with a system based only on wind power. As a result, the paper estimates the balancing costs of wave converters, which are compared with the current balancing costs of wind turbines. The opportunities of a combined wave and wind scenario compared to the only-wind scenario are examined. The study is based on day-ahead forecasts and on real-time theoretical power productions from wave converters and wind turbines, throughout a 5month autumn and winter period, at Hanstholm, Denmark. Results show balancing costs of wave converters are 35 to 47% smaller than those brought by wind turbines. When wave converters are combined balancing costs keep low, 45% lower than for wind turbines. Finally, a diversified scenario of wind and wave technologies brings balancing costs 35 to 45% down compared to the only-wind scenario. Beyond the technical benefits of diversified scenarios, the paper identifies an economic benefit of combining wind and wave power productions.