Households with prepay energy meters are weighed down by more than £1billion of debt, say campaigners.
Repayments are deducted from credit and can deny households energy they need for heating, cooking or medical equipment.
Junnie Braithwaite, 56, from North East London, is among those affected. She said: “I live in a socially rented apartment over two floors and need a stairlift because of fibromyalgia and arthritis.
“Due to rising energy prices and £600 of energy debt I can no longer afford to operate my stairlift. This debt is based on an estimation as I am unable to read my meter.
“I’ve been forced into unpayable debt because of my situation and it’s left me feeling suicidal.”
According to the group Debt Justice, prepay energy users take an average of four-and-a-half years to pay off electricity debt, and four years to pay off gas debt. It says debt payments expose people to the “deadly effects” of cold and damp homes.
Joe Cox, senior policy officer at Debt Justice, added: “The fallout from record energy prices and the huge build-up of debt could impact millions of households for years.
“We need to pause energy debt enforcement, write down unpayable debt and reform the system to ensure everyone has access to the energy they need.”
In the wake of controversial tactics used by agents working on behalf of British Gas, suppliers suspended forced installation of prepay meters to recover money.
But the debt remains hanging over hundreds of thousands who already have a prepay account.