Johannes Teyssen, the chief executive at utility E.ON and one of the most powerful executives in German energy, amid a fierce discussion in Europe’s largest economy on future emission costs has proposed a CO2 levy to finance the expansion of renewable power.

Each ton of CO2 emitted in power generation, heating or transport should cost €35 ($39), Teyssen told shareholders at the company’s annual meeting, which he said would bring in €25m in tax revenue.