What Happened to Paks Nuclear Power Plant Emergency Shutdown?

The Paks Nuclear Power Plant, a cornerstone of Hungary's energy independence, is currently grappling with an unprecedented crisis: an emergency shutdown of its four operational units. As of late July 2026, record-low water levels in the Danube River, which provides vital cooling water, have forced the plant operator, MVM Paksi Atomeromu, to initiate a phased reduction in output, leading to an inevitable full shutdown. This event marks the first time in the plant's 42-year history that it will cease full operation due to environmental conditions. The plant, with an installed capacity of approximately 2 GW, typically generates nearly half of Hungary's electricity.

The immediate cause of the shutdown is the critically low water level of the Danube. While there is still sufficient water in the river for cooling, the water level has fallen below the suction pipes used to extract water for the condensers of the reactor units, rendering the pumps inoperable. Danube levels at Paks reached a record low of 121 cm below the reference level on July 30, 2026, and were projected to fall further. This situation has been exacerbated by riverbed deepening due to reduced sediment transport and decades of dredging, combined with the effects of global climate change leading to increased extremes and a lack of spring floods in 2026. Output reductions began on July 27, with Unit 3 being completely shut down on July 30, 2026, and a full plant shutdown anticipated within 24-72 hours.

The consequences of this emergency shutdown are significant for Hungary's energy sector. The domestic generation shortfall, estimated at around 2 GW, will need to be covered by imports, with Prime Minister Peter Magyar stating that Hungary has 3.6-3.8 GW of import capacity. The government is preparing a multi-layered contingency plan, including mobilizing domestic power plant reserves and urging the public to postpone energy-intensive activities during peak hours. The situation has also led to a surge in electricity contract prices. While the shutdown is temporary and the plant can be restarted once water levels recover, the duration of the outage remains uncertain, with a restart unlikely in the short term if Danube levels continue to drop.

Beyond the immediate crisis, the Paks Nuclear Power Plant has been pursuing a long-term strategy for its existing units. In December 2023, the operator, MVM Paksi Atomeromu Zrt, notified the European Union of its intention to extend the operating lifetime of the four VVER-440 units to 70 years, a process expected to take approximately a decade. These units, which began commercial operation between 1982 and 1987, had already received a 20-year lifetime extension in 2005, pushing their scheduled shutdown dates to between 2032 and 2037. This further extension aims to ensure Hungary's energy security and reduce carbon emissions.

In parallel, the Paks II expansion project, involving the construction of two new Russian-designed VVER-1200 reactors, has seen significant developments. After years of delays, the 'first concrete' for the foundation of Unit 5 was poured on February 5, 2026, officially marking the project's transition to 'under construction' status according to IAEA standards. This project, backed by a EUR 10 billion Russian state loan, aims to add 2.4 GW of capacity and significantly boost Hungary's energy independence. However, the new Hungarian government, which took office in May 2026, has announced a review of the Paks II project's contracts and the overall investment process, with some suggesting construction should be suspended during this review due to accumulated delays and increased costs. Earthworks for Unit 6 are also underway.

As of July 31, 2026, the Paks Nuclear Power Plant is on the brink of a full emergency shutdown due to environmental factors, a situation that highlights the vulnerability of even critical infrastructure to climate change impacts. While the existing units await a potential 20-year lifetime extension, the Paks II project continues its slow progress under a cloud of governmental review. The immediate focus remains on managing the current energy crisis and ensuring the safe maintenance of the shut-down units, with hopes for a restart once the Danube's water levels normalize.