E.ON, Germany's biggest power supplier, said Wednesday the difficult business environment pushed it deeply into the red last year, but stressed that the group is "past the worst".
E.ON said in a statement it booked a net loss of 2.219 billion euros ($2.9 billion) in 2011, compared with profit of 5.853 billion euros a year earlier.
Underlying profits, as measured by earnings before interest, tax, depreciation and amortisation (EBITDA), slumped 30 percent to 9.293 billion euros, while sales grew by 22 percent to 113 billion euros.
"E.ON continued its consolidation course in a difficult business environment in 2011 and is past the worst," said chief executive Johannes Teyssen.
"For 2012, we expect to post an earnings increase that will continue in subsequent years."