Akhtar Naveed, Geyer Beate, Rockel Burkhardt, Sommer Philipp S, Schrum Corinna
Institute of Coastal Systems-Analysis and Modeling, Helmholtz-Zentrum Hereon, Geesthacht, Germany.
Sci Rep. 2021 Jun 3;11(1):11826. doi: 10.1038/s41598-021-91283-3.
The European Union has set ambitious CO reduction targets, stimulating renewable energy production and accelerating deployment of offshore wind energy in northern European waters, mainly the North Sea. With increasing size and clustering, offshore wind farms (OWFs) wake effects, which alter wind conditions and decrease the power generation efficiency of wind farms downwind become more important. We use a high-resolution regional climate model with implemented wind farm parameterizations to explore offshore wind energy production limits in the North Sea. We simulate near future wind farm scenarios considering existing and planned OWFs in the North Sea and assess power generation losses and wind variations due to wind farm wake. The annual mean wind speed deficit within a wind farm can reach 2-2.5 ms depending on the wind farm geometry. The mean deficit, which decreases with distance, can extend 35-40 km downwind during prevailing southwesterly winds. Wind speed deficits are highest during spring (mainly March-April) and lowest during November-December. The large-size of wind farms and their proximity affect not only the performance of its downwind turbines but also that of neighboring downwind farms, reducing the capacity factor by 20% or more, which increases energy production costs and economic losses. We conclude that wind energy can be a limited resource in the North Sea. The limits and potentials for optimization need to be considered in climate mitigation strategies and cross-national optimization of offshore energy production plans are inevitable.
欧盟设定了雄心勃勃的二氧化碳减排目标，这刺激了可再生能源的生产，并加速了北欧海域（主要是北海）海上风能的部署。随着海上风电场（OWF）规模的不断扩大和集群化，其尾流效应变得更加重要，尾流效应会改变风况并降低下风处风电场的发电效率。我们使用一个实施了风电场参数化的高分辨率区域气候模型，来探索北海海上风能的生产极限。我们模拟了北海现有和规划中的海上风电场在近期的情景，并评估了由于风电场尾流导致的发电损失和风的变化。根据风电场的几何形状，风电场内的年平均风速亏缺可达2 - 2.5米/秒。平均亏缺随风距减小，在盛行西南风时，下风方向可延伸35 - 40公里。风速亏缺在春季（主要是3 - 4月）最高，在11 - 12月最低。大型风电场及其相邻位置不仅会影响其下风处涡轮机的性能，还会影响相邻下风处风电场的性能，使容量系数降低20%或更多，这增加了能源生产成本和经济损失。我们得出结论，风能在北海可能是一种有限的资源。在气候缓解策略中需要考虑其极限和优化潜力，对海上能源生产计划进行跨国优化是不可避免的。
