ENERGY giant Centrica said today that mild spring and autumn weather fuelled a 30% slide in profits at its residential arm British Gas to �522million last year.

ENERGY giant Centrica said yesterday that mild spring and autumn weather fuelled a 30% slide in profits at its residential arm British Gas to �522million last year.

The UK’s biggest gas supplier, which lost 97,000 customers in 2011, said the unseasonably warm weather in spring and autumn had led to a 21% drop in average household gas consumption and a 4% fall in electricity.

The slide in profits for the year to December 31 comes despite the energy supplier increasing gas and electricity bills by an average of 18% and 16% respectively in August. It has since announced a 5% cut in electricity prices, in January.

Group-wide, however, Centrica reported a 1% increase in adjusted operating profits to �2.41billion as its upstream gas and oil exploration business saw profits jump 33% to �1bn.

Some of the fall in profits in supplying gas and electricity to households has been clawed back through residential services such as boiler repairs, where profits were 10% higher at �264m.

The upstream business smashed through the �1bn barrier for the first time, recording a 33% increase in profits to �1.02bn.