"There are two conditions we see for these plants: they need clarity about the dimension and location of a hydrogen core transport grid and...a capacity premium...," said chief executive Markus Krebber in a call with reporters after earnings for the first half of the year.

Germany's economy minister earlier this month said he had made a "breakthrough" in talks with the European Commission on the plans but has yet to agree on how they will be subsidised.

(Reporting by Vera Eckert and Christoph Steitz, editing by Matthias Williams)