The party's deputy leader in the Bundestag, Bärbel Höhn, told public broadcaster Deutschlandfunk on Tuesday that energy companies were failing to pass along lower costs for power to their customers and that recent price hikes were unjustified.
Noting that prices on the European Energy Exchange in Leipzig had fallen around 40 percent in the past two years, Höhn said consumers should have lower power bills and utilities could not blame renewable energy for the higher costs.
She called for curbs on the market influence of the biggest energy firms to avoid unjustified hikes in electricity prices in the future.
Ingrid Nestle, the Greens' spokeswoman for energy issues in parliament, said power giant RWE was misusing renewable energy as an argument for milking customers.
“But in fact the price hikes only make electricity production at nuclear power plants more lucrative,” she told business daily Handelsblatt.
She said this focus on nuclear power was in turn was blocking the expansion of renewable energy, estimating RWE would glean an extra €100 million from its latest price increase starting in August.
The company said it would raise power bills for some two million households by 7.3 percent because of higher electricity costs partly related to supporting the development of renewable energy sources.