The industry regulator said that 10 suppliers had handed over compensation and goodwill payments to just over 34,000 customers. The total came to around £7m.
Ofgem said those affected, between January 2019 and September last year, had more than one electricity meter point at their property recording energy usage.
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It explained that while suppliers were allowed to apply multiple standing charges for homes with multiple electricity meters, it meant that some were “erroneously charged more than is allowed under the price cap when combined with unit rates”.
The companies affected were revealed as E.ON Next, Ecotricity, EDF Energy, Octopus Energy, Outfox The Market,
OVO Energy, Rebel Energy [no longer trading], So Energy, Tru Energy and Utility Warehouse.
Of those, Octopus Energy accounted for the majority of the customers hit.
Ofgem said that the near-21,000 customers impacted at the supplier had received compensation of £2.6m and goodwill payments of almost £550,000.
The redress was revealed at a time when energy bills remain elevated due and debts at record levels in the wake of the 2022 price shock caused by Russia’s invasion of Ukraine.
Higher wholesale natural gas prices over the winter months meant that the price cap actually rose in April when a decline would normally be seen.
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The latest forecasts suggest, however, that bills should start to decline for the forseeable future.
Charlotte Friel, director of retail pricing and systems at Ofgem, said of its compliance operation: “Our duty is to protect energy consumers, and we set the price cap for that very reason so customers don’t pay a higher amount for their energy than they should.
“We expect all suppliers to have robust processes in place so they can bill their customers accurately. While it’s clear that on this occasion errors were made, thankfully, the issues were promptly resolved, and customers are being refunded.”
The watchdog added that all ten suppliers had updated their systems and processes to prevent the error occurring in future.
