The West still relies on the Russian nuclear power industry and vice versa, a review has warned.
It said the “significant” interdependence has protected Russia from further European sanctions.
But reducing the West’s reliance risks increasing costs, the annual World Nuclear Industry Status Report said.
Since Russia’s full-scale invasion of Ukraine in 2022, Western countries have tried to wean themselves off Russian energy supplies, and enforced harsh sanctions in a bid to dent Russia’s war chest.
Some of the five EU countries that use VVER reactors, which are designed by Russia and use Russian fuel, have sought out alternative fuel sources, largely from the United States.
Even so, several stockpiled Russian fuel last year, driving up imports.
“Interdependence between Russia and its Western partners remains significant,” said the report, led by energy consultants Mycle Schneider, a sceptic of nuclear power, and Antony Froggatt, formerly of the UK’s Chatham House.
And some Western companies like a section of French state power company EDF rely on Russian state-built reactors around the world to sell their parts, the authors wrote.
“With [Russian nuclear giant] Rosatom implementing all 13 nuclear-power reactor construction sites started outside China over the past five years, providers of parts, e.g. France’s Arabelle turbines, do not have any other foreign customer besides Rosatom,” it said, referring to a unit of EDF.
In January, the previous UK government announced a £22m pot of money to develop of a new type of nuclear fuel – High-Assay Low-Enriched Uranium, currently only commercially produced by Russia – in an attempt to severe energy ties with Moscow.
The report also said the “close mutual industrial and market interdependencies” between Russian and Western nuclear industries partially explain “European hesitations to impose sanctions on the nuclear sector”.
“Efforts to reduce or eliminate Russia dependencies in natural uranium, conversion, and enrichment services will likely increase costs,” it added.
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The overview of global nuclear electricity generation found it grew by 2.2% last year to 2,602 net terawatt hours, providing 9% of the world’s electricity.
In the UK, the new government has said it is committed to the planned Sizewell C nuclear power station in Suffolk, although it has not yet made a final investment decision.
The energy department is also reviewing early plans drawn up by the last administration for another major plant in North Wales.
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It comes as a separate report on Thursday warned many Ukrainians face more blackouts when winter bites, as Russia this year escalated attacks on its energy infrastructure, and a gas supply contract it has with Russia’s Gazprom is due to expire at the end of this year.
The International Energy Agency (IEA) said Ukraine faces a power supply shortfall by about a third of peak demand, following Russian strikes on power plants, heat plants, transmission networks and other sites.
This has already caused rolling blackouts and limited electricity supply to some regions for a few hours a day, the IEA said.