The UK power system enters winter 2025/26 in a stronger position than in recent years. The National Energy System Operator’s (NESO) early winter outlook points to the highest operational margins since 2019, thanks to steady domestic generation, greater demand-side flexibility, and the addition of new interconnection capacity such as the 1.4 GW Viking Link. On paper, this reduces the likelihood of scarcity pricing events and eases pressure on forward baseload contracts.
However, interconnectors are only as reliable as the markets they connect to. France’s nuclear fleet remains a potential point of stress. Strong availability allows France to export to the UK, helping to hold down baseload prices, but unexpected outages — whether from corrosion, technical faults, or weather-driven constraints — could quickly reverse flows and leave the UK paying higher import prices.
Despite robust domestic margins, the UK’s increasing reliance on cross-border flows means forward power prices remain highly sensitive to developments abroad.
