“Due to the continuing boom in solar energy, many power stations throughout the sector and across Europe are no longer profitable to operate,” the utility said in its second quarter financial report, citing a two-thirds drop in its conventional power generation division's operating result.
On top of the 3500MW the company plans to retire, a further 897MW of coal and lignite is under "intense review", while the prospects for an additional 1450MW of contracted hard coal plants are being considered.
Most of the plants would be retired between 2013 and 2016, RWE said.
Over the past four years, the German energy market has been oversupplied due to a boom in solar energy following increased funding for renewables from the government.
With subsidies flowing towards renewable energy sources, prices have dropped, making the operation of conventional power generating facilities uneconomical.