Design and operation of power systems with large amounts of wind power:Final summary report, IEA WIND Task 25, Phase four 2015-2017

This report summarises recent findings on wind integration from the 17 countries and Wind Europe participating in the International Energy Agency (IEA) Wind collaboration research Task 25 from 2015–2017. Both real experiences and studies are reported. Many wind integration studies incorporate solar energy, and most of the results discussed here are valid for other variable renewables in addition to wind.The participating countries report increasing shares of wind on average: 43% annual energy in Denmark, about 25% in Ireland, Portugal and in the province of Prince Edward Island in Canada, and more than 30% in Iowa, South Dakota, Kansas, and Oklahoma in the USA. During certain hours more than 100% instantaneous share has been achieved in Denmark and Portugal, more than 80% in Italy and Germany, and the island power system of Ireland has seen 79% of demand, against an allowable 65% share from non-synchronous sources.The national case studies address several impacts of wind power on electric power systems. In this report, they are grouped under long-term planning issues and short-term operational impacts. Long-term planning issues include grid planning and capacity adequacy. Short-term operational impacts include reliability, stability, reserves, and maximising the value of wind in operational timescales (balancing related issues). The first section presents the variability and uncertainty of power system-wide wind power, and the last section presents recent wind integration studies for higher shares of wind power. The appendix provides a summary of ongoing research in the national projects contributing to Task 25 for 2018–2020