TOKYO - Tokyo Electric Power Co (Tepco) plans to raise electricity rates for companies from April to help offset the rising costs of fuel to run thermal power plants after the Fukushima disaster shut down most of its nuclear reactors.

The utility company will announce the size of the increase in January, it said in a statement. It will also seek approval from the government to raise tariffs for households "as soon as possible", according to the statement.

Tepco estimates its fuel costs will rise by 830 billion yen ($10.6 billion) to 2.31 trillion yen in the year ending March 2012. Only two of the company's 17 nuclear reactors are now running after the March 11 earthquake and tsunami wrecked its Daiichi plant. Other reactors closed for maintenance haven't been approved for restart because of safety concerns. Tepco supplies 29 million companies and households in the Tokyo area.