Electricity supply and demand in the European market: the effect on generation adequacy in a dunkelflaute period
Year: 2025
Type: article
Abstract: The recent energy crisis and uncertainty in reaching net-zero goals highlight the need to assess risks in the electricity mix and future developments. With the phasing out of coal power plants, aging gas and nuclear fleets, and ongoing decommissioning, the amount of flexible capacity will be significantly reduced in the North-Western European (NWE) energy system, putting the electricity system under pressure. This study evaluates generation adequacy in three 2035 electricity mix scenarios across 11 European countries, with a central focus on adequacy during a prolonged dunkelflaute period, assessed through expected energy not served (ENS). A baseline analysis identifies periods of system strain based on flexible capacity availability during peak residual demand in the EU-27, Norway, Switzerland, and the United Kingdom. The worst-case two-week dunkelflaute was determined based on the highest residual demand, with non-flexible generation simulated using capacity factors from eight climate years. The dunkeflaute which occurs in times when renewable sources are hardly available for power production and is a growing challenge for our modern power systems in which conventional flexible capacities are shrinking fast. Our results indicate that while capacity is generally sufficient for unexpected demand spikes, vulnerabilities emerge due to reliance on non-flexible onshore and offshore wind and PV production. During the dunkelflaute period, ENS is observed in all scenarios, with Germany particularly at risk, experiencing an hourly average ENS at GWh scale. Storage and demand-side response showed limited ability to cover persistent shortages, and while cross-border transmission alleviates system strain, it cannot fully resolve national shortfalls during widespread low renewable output. All modeled countries face ENS in an additional scenario considering only currently planned capacity expansions. These findings highlight the need for flexible capacities, with EU-level coordination and support policies essential to ensure generation adequacy during dunkelflaute periods across the entire region.
Source: Energy Policy
Authors: Andreas Christian Beck-Bang, Simon Bay Overgaard, Dogan Keles
Institution: Technical University of Denmark
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,940
OpenAlex ID: W7084768176