MADRID, Oct 4 (Reuters) - Spanish lobby group Foro Nuclear has filed a legal challenge with the country's top court against a 30% increase of the nuclear waste levy, while the main operators of the plants are moving to join the fight.

The lobby group, whose members include the energy companies operating Spain's reactors and firms active in the industry, filed the legal action to the Supreme Court in late September, it told Reuters on Friday, declining to further comment.

Energy giants Iberdrola (IBE.MC) , opens new tab and Endesa (ELE.MC) , opens new tab, the main operators of the country's nuclear fleet, are moving to file their own appeals, people familiar with the matter told Reuters.

In June, the government raised the levy to 10.36 euros ($11.36) per megawatt hour from 7.98 euros due to rising storage and disposal costs.

That means a cost of around 130 million euros more every year for the Spanish nuclear fleet as a whole, in addition to the 450 million it already pays, according to Foro Nuclear.

The lobby group has also filed administrative appeals against the government's nuclear waste plans.

Madrid's plan to shut the country's reactors, which generate about a fifth of its electricity, by 2035 has faced opposition from industry and business lobbies.

The government estimates that dismantling the plants and managing radioactive waste will cost about 20.2 billion euros, to be paid for by a fund supported by the plants' operators.

Naturgy (NTGY.MC) , opens new tab and EDP (EDP.LS) , opens new tab have minor stakes in some plants.

Iberdrola, Endesa and the Energy Ministry declined to comment.

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https://www.reuters.com/business/energy/spains-nuclear-waste-levy-hike-faces-legal-challenges-2024-10-04/