Centrica, the country's largest energy supplier, said domestic gas and electricity prices should increase an average of 6 percent for consumers starting Friday. The company said that some of those costs are associated with investments meant to upgrade the national grid and usher in a low-carbon economy.
"These costs, which are out of our control, have added around $79 to the cost of supplying the average household," the company said. "We have also experienced rising wholesale gas prices, which are 13 percent higher this winter than last."
The company added that residential gas consumption for the first 10 months of the year was 9 percent higher than for the same period in 2011 because of colder temperatures and energy efficiency measures.
A full-year report on profits is expected from the energy company in February. It said its year-on-year earnings for 2012 are in line with market expectations.
"In U.K. residential services we remain on track to deliver double-digit profit growth, primarily due to the delivery of cost efficiencies across the business," the company stated.
British utility companies are under pressure from regulators examining allegations of price manipulation in the natural gas market.