One in every six prepayment energy customers has gone without gas or electricity because of high costs, problems with topping up or faulty meters, a study has found.
Today is the start of the industry's winter moratorium on disconnections for vulnerable customers and those with young children, but Citizens Advice has called for suppliers, the Government and Ofgem to look into greater protection for those on prepayment meters.
It found 1.6 million prepayment customers "self disconnected" their supply every year and had no protection from the "stark choice of top up or drop out" over the winter.
The charity said half of those who disconnected their supply last year (54%) were seriously concerned about being able to afford to top up their gas or electricity meter this winter - up by 6% since 2010.
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It found some were going without gas or electricity because of rising prices and unstable incomes, while reduced working hours, loss of employment, illness or a change in benefits could lead to erratic finances and not enough money to cover day to day costs.
Figures showed that children lived in half (47%) of the households that used prepayment meters.
Citizens Advice chief executive Gillian Guy said: "Going without gas or electricity is a grave necessity, not a choice.
"The budgets of many prepayment meter users are stretched so thin that not topping up their energy meters for a few days, or even weeks, is the only way to get by.
"It is very concerning that, as temperatures start to drop and the nights draw in, some prepayment consumers will be living in cold, dark homes because they can't afford to put money on their meters.
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"Energy companies are doing the right thing by putting a freeze on disconnections for vulnerable households but industry, Government and the regulator need to look at how this can be extended to prepayment consumers too.
"Self-disconnection is just the tip of the iceberg when it comes to problems faced by prepayment consumers. Higher costs, a small or non-existent choice of tariffs and inconvenient ways of topping up are some of the extra challenges faced by pay-as-you-go energy consumers."
Citizens Advice has launched the Fair Play for Prepay campaign calling for better customer service and support with easier top-ups and a fair choice of tariffs.
:: TNS surveyed 14,226 prepayment customers in 2013/14.
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