The average household’s annual energy bill of £1,252 now accounts for 11pc of a couple’s basic state pension of £11,175 a year, the study by price comparison website uSwitch.com found.
The cost of energy is now the top household worry for Britons (90pc), ahead of the rising cost of food (77pc) and mortgage payments (42pc).
Almost a third of consumers (32pc) say that household energy is unaffordable in the UK, the poll found.
While the average UK household income has increased by 20pc from £32,812 in 2004 to £39,468 today, the average energy bill has risen by 140pc, according to uSwitch figures.
Households were spending an average of £522 a year for their energy in 2004, but now pay £1,252 a year – 3.2pc of income or double the 1.6pc of eight years ago.
Britons now have an average of £297 of disposable income left each month after all essential household bills are paid.
The study found 83pc of people believe that rising energy bills have had an impact on their disposable income, with 17pc of these reporting that they no longer have any disposable income as a result and 27pc saying energy bills have reduced their disposable income dramatically.
Director of consumer policy at uSwitch.com Ann Robinson said: “This is the cold reality facing households today; in less than 10 years our energy bills have rocketed by 140pc. The break-neck speed at which energy prices have sprinted upwards has caught many people unawares. Consumers are still playing catch-up.
“Energy now accounts for a significant slice of household income which is why the numbers rationing their energy use have risen so steeply in recent years. But going cold or without is a short-term and potentially harmful fix and not a long-term solution.
“The fact is that consumers can control how much they spend on energy by making their homes more energy-efficient and paying less for the energy they do use by moving to a competitively-priced energy plan.
“Those who are on a low income or benefits could even benefit from free insulation from their energy supplier, so it’s always worth contacting them first to see what financial help you can get.”