Energy bills will increase by approximately one per cent this autumn, adding £17 to annual household expenses, according to the latest forecast for Ofgem's price cap.

Cornwall Insights has predicted the average yearly bill will reach £1,737 for typical usage, when the regulator's new pricing structure takes effect in October.

The firm's analysis indicates this upward adjustment contradicts earlier expectations. The energy consultancy had previously anticipated a reduction in costs during July's assessment, when bills were forecast to decrease from the present £1,720 level.

Ofgem will announce what level the energy price cap will be set at on August 27, which determines the maximum amount suppliers can charge households per unit and electricity.

Energy bills are predicted to rise later this year

The increase reverses July's projections of declining bills. Cornwall Insight's revised forecast reflects anticipated regulatory adjustments during the forthcoming pricing period.

Notably, the consultancy highlighted that expanding the Warm Home Discount programme would contribute approximately £15 to standard bills while delivering £150 assistance to an additional 2.7 million people.

Market volatility in electricity and gas prices has persisted, influenced by international political developments and questions surrounding American trade policies.

These factors have contributed to the unexpected reversal in pricing predictions, despite earlier optimism linked to reduced tensions in the Middle East.

Ofgem is responsible for setting the UK energy price cap | GETTY

Cornwall Insight attributes the forecast to Ofgem's anticipated changes. The expansion of the Warm Home Discount programme will add approximately £15 to standard bills whilst providing £150 support to 2.7 million additional recipients.

Dr Craig Lowrey, principal consultant at Cornwall Insight, said: "News of higher bills will not be welcomed by households, especially as winter approaches."

He explained that whilst the additional charges aim to assist those requiring support, standard bills will rise regardless of comparatively reduced wholesale expenses.

"It's a reminder that the price cap reflects more than just the market price of energy," Dr Lowrey added.

The consultancy anticipates a modest reduction in January's pricing, though this remains contingent on international political developments, seasonal weather conditions and potential policy cost adjustments.

Future expenses might incorporate funding for new nuclear generation infrastructure.

Household bills are likely to go up in autumn

"The real hope for lasting relief lies in the longer-term transition towards clean power and energy independence, which offers the greatest prospect of both stability and lower costs," he stated.

Simon Francis, coordinator of the End Fuel Poverty Coalition, said: "We’re about to face our fifth winter of the energy bills crisis, with the average family still paying hundreds of pounds more than they did just a few years ago.

"One of the main culprits is the price of gas, which tripled at the height of the crisis and is still 81 per cent higher than before. What's more, the North Sea, once seen as the nation's source of gas, is in terminal decline and it simply cannot provide power for our heating systems for the long term.

"If we want affordable, secure energy, we have to look beyond gas and slash the cost of clean electricity."