You can never be too rich or too thin, I guess. And if you’re Germany, you can never tax too much, either.

Germany’s biggest utilities, still reeling from the country’s early exit from nuclear power, scored a major victory Tuesday when a Hamburg court said the national tax on nuclear fuel rods may violate European law.

The Hamburg finance court said it “cannot assess beyond any doubt” whether the tax on nuclear fuel used for electricity generation complies with European law. It will now ask the European Court of Justice to decide whether the levy conforms with rules that prohibit member states from creating new taxes on electricity for “general budget financing purposes.”

The tax was introduced at the beginning of 2011 and came as part of an extension of nuclear reactors’ operating lives that the government had agreed on. However, the nuclear disaster at Japan’s Fukushima power plant in March of that year triggered a U-turn in German energy policy, with Chancellor Angela Merkel ordering the immediate shutdown of the oldest plants and the early phaseout of nuclear energy by 2022. Out of 17 reactors that were in operation in March 2011, only nine are still producing power. But the fuel-rod tax remains in place, to the utilities’ annoyance.

Das Hamburger Finanzgericht will vom Europäischen Gerichtshof (EuGH) in Luxemburg zentrale Fragen zur umstrittenen Brennelementesteuer klären lassen.