Polish TSO PSE Activates Evening Power Reserve for Second Time in One Week
PSE's back-to-back reserve calls in early August add Poland to a growing list of European grid operators stretched by summer heat and variable renewables.
Hungary's Paks nuclear plant was expected to resume power generation as early as Monday evening (2026-08-10) after one turbine was switched on, Prime Minister Peter Magyar announced. The news offered partial relief to regional grids. Poland's TSO PSE had called on evening power reserves for the second time in one week four days earlier, Montel reported on Thursday (2026-08-06).6,5
European gas and power markets had already priced in the stress. ICE Endex TTF front-month climbed 9.59% to €60.82 per megawatt-hour on August 10 (2026-08-10). German day-ahead power rose 3.64% to €135.95 per megawatt-hour on the same day. Both moves suggest markets are registering supply pressure extending beyond a single weather event.
Montel's Poland report sits behind a registration gate, limiting public detail. The headline alone establishes that PSE called on its evening reserve mechanism twice within one week — a frequency Montel treated as unusual. Volumes and exact timing were not available in the public excerpt.5
Poland is not alone. Spain's TSO Red Electrica activated its SRAD demand-curtailment service between 22:18 and 24:00 CET on Wednesday (2026-07-22), trimming 943 MW of industrial load after wind output dropped unexpectedly. That was the second such call in a week, a company spokeswoman told Montel.4
The UK showed the pattern earlier. The National Energy System Operator issued a second evening supply warning on Friday (2026-06-26) as temperatures climbed across Europe — an unusual move for NESO in summer months. Gas-fired generators earned roughly £10 million in Balancing Mechanism revenue between June 22 and June 25, LCP Delta data show.2
Poland's exposure to evening generation shortfalls has grown alongside its renewable build-out. Wind accounts for 14.7% of the country's energy mix, up from 0.3% two decades ago, and the offshore programme in the Baltic — the largest energy investment in Poland's modern history — could cost more than $140 billion over 15 years, the Economist reported. Greater wind penetration sharpens the gap when output falls short of evening demand.1
Gas supply security has been addressed separately. The LNG terminal at Swinoujscie has been expanded to 8.3 bcm per year. A second facility in Gdansk targeting 6.1 bcm of additional capacity is due in 2028. The pipeline from Norway through Denmark, launched in 2022, adds up to 10 bcm in capacity. But these investments address fuel import exposure, not the evening electricity shortfalls forcing PSE to reach for reserves.1
Cross-border flows add a further complication. Polish power traders called on PSE on Thursday (2026-07-23) to clarify how EU changes to cross-border electricity trade rules, due in November, would reshape their positions. "What we know now is that we know nothing for sure really," the head trader at one Polish firm told Montel.3
PSE has not indicated how many more reserve calls the system may require before autumn cooling eases the evening peak. Regional capacity from Hungary's partial Paks restart could help stabilise cross-border supply before September. The November EU rule change for cross-border capacity allocation, which Polish traders have already flagged as opaque, is a regulatory overhang the market has yet to absorb.6,3