Dunkelflaute
In the renewable energy sector, a dunkelflaute (German: [ˈdʊŋkəlˌflaʊtə] ⓘ, lit. 'dark doldrums' or 'dark wind lull', plural dunkelflauten) is a period of time in which little or no energy can be generated with wind and solar power, because there is neither wind nor sunlight. In meteorology, this is known as anticyclonic gloom.