E.ON, Germany's largest utility company, today posted a record loss for the second year in a row following asset writedowns worth more than half its market value.
The figures have cast doubts over plans to spin-off its ailing power plants later this year.
E.ON, in the process of spinning off its power generation and energy trading business into a new publicly traded company called Uniper, said its net loss more than doubled to €7 billion in 2015, from €3.16 billion euros in 2014.
Analysts had, on average, expected a net loss of €6.48 billion.
Germany's traditional power companies have been hammered by a surge in renewable energy, plunging wholesale electricity prices and the country's plans to abandon nuclear power.
As a response, E.ON wants to spin off its energy trading and most of its power generation into Uniper, to focus on renewables, networks and services.
E.ON warned future profits, dividends and cash flows were expected to decline further amid worsening conditions in the power sector.
"Our numbers reflect the far-reaching structural transformation that our industry is experiencing and that continues unabated in the current year," chief executive Johannes Teyssen said.
The course ahead will be tougher and longer than anticipated," he added.
E.ON blamed €8.8 billion in writedowns on its power plants, most of which have slid into loss as they no longer run the hours necessary to turn a profit, being increasingly replaced by solar and wind power.
Shares in E.ON have lost more than 40% over the past twelve months.
