CEO of owner Centrica says service will be ‘my obsession’ as profits slump by a third to £2.3bn

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The boss of British Gas has said that losing its spot as Britain’s biggest energy supplier for the first time in four decades should “galvanise” its staff to focus on customer service and lowering bills.

Chris O’Shea, the chief executive of Centrica, which owns British Gas, said monitoring its customer service was an “obsession” that would continue after Octopus Energy toppled it from the position as the largest energy supplier in the market last year.