A comprehensive new study by Wood Mackenzie reveals the growing challenge of "dunkelflaute" – prolonged periods of low wind and solar generation – as Europe transitions to renewable-dominated power systems. The research shows these events are driving extreme price volatility and exposing critical vulnerabilities in energy security across the continent.
Dunkelflaute is an increasingly familiar concept in European power markets, especially following two widely covered events in November and December 2024.
According to the report “Weathering the lulls: the risks and opportunities of dunkelflaute,” On average, European markets will be exposed to 1.6 dunkelflaute events annually, although significant regional variation exists. Northern markets, especially those relying on offshore wind, suffer the greatest exposure, due to correlated wind fleets and limited spatial diversity. Southern European markets have less dunkelflaute risk, as midday solar remains strong even in winter, aligning more closely with peak demand and enabling effective load shifting via battery storage.
For example, Belgium experiences the highest frequency with 3 events per year, while Portugal records zero. Events are most prevalent between November and January, with 41% lasting longer than 3 days.
According to the report, market consequences range from extreme prices to dramatic shifts in the power supply mix. In Germany, the prices observed during just two dunkelflaute events in 2024 were sufficient to generate over 50% of the wholesale revenues of gas peaker plants. During November 2024's event, German intraday prices spiked to €820/MWh. Gas and coal generation ramped up dramatically, with German imports averaging 10.5 GW over three days.
A broader takeaway is that the rise of dunkelflaute may force European policymakers and investors to rethink the balance between decarbonisation goals and system resilience. Beyond technical fixes like storage and grid upgrades, this challenge could accelerate debates over market design, cross-border energy cooperation, and the role of firm low-carbon capacity such as nuclear or advanced gas with carbon capture. In other words, managing these dark lulls will not just be an engineering problem – it will be a political and strategic test of Europe’s ability to deliver both clean and dependable power.
