REFILE-UK's Centrica had top profit margin from supplying energy -Ofgem
LONDON Nov 25 (Reuters) - Centrica made the highest profit margin last year out of Britain's 'Big Six' power utilities from supplying electricity and gas to customers at 6.6 percent, a report by regulator Ofgem showed on Monday.
The cost of consumers' monthly energy bills has climbed to the top of the political agenda in recent months as politicians gear up for a 2015 election campaign, which is likely to focus on the cost of living after years of austerity measures.
Britain's utilities have announced steep price increases for this winter, angering consumers who often accuse them of pocketing extra profits from offering essential services.
The country's 'Big Six' suppliers are Scottish Power , EDF Energy, SSE, Centrica, RWE npower and E.ON.
Ofgem's report analysing the profits of large energy companies showed that Centrica, the owner of top gas supplier British Gas, had the highest profit margin in 2012 at 6.6 percent for supplying electricity and gas to households and industry.
EDF Energy had the lowest margin, making a loss of 1.4 percent last year.
The utilities' average profit per customer rose to 53 pounds ($85.79) in 2012, up from 30 pounds in 2011, mainly due to a rise in consumption during a winter with below-average temperatures, the report showed.
The average household energy bill rose by 168 pounds, of which 75 pounds were attributed to wholesale price rises and 60 pounds to an increase in the cost of paying for network usage and government policies.
The report, based on findings from accountancy firm BDO which analysed the companies' full-year statements, also gave a glimpse of profits on the energy generation side.
It showed that profit margins in energy production were 19.9 percent last year, down from 24.4 percent the previous year, amounting to a total of 2.1 billion pounds in profits for the 'Big Six'.
Ofgem said, however, that its calculation for generation profits did not include the large upfront costs required to build new power plants.