Shower with other people, go to bed early and stop drinking tea if you want to cut expenses, suggests British energy firm Frist Utility after whopping their prices up by 18 per cent.

Frist Utility, Britain’s biggest independent energy firm with 120,000 customers, has said that customers should follow an “energy diet” where two days of the week, they save and the remaining five days they use whatever electricity they want.

“Just stick to the low-usage energy plan on fast days, then use what you like on the other five and you could save an average of £154 a year,” the company, which charges an average of £1,120 for electricity and gas, said in a statement.

Showering together can save £34 a year, while turning off the telly and turning out the lights can knock another £18 off your bill, Frist Utility said. Playing a board game and microwaving meals instead of cooking them could also save £12 a year.

“Staying away from a hot drink twice a week could save you approximately £10 a year,” the company continues.

Ed Kamm, a spokesman for Frist Utility, defended the controversial advice.

“These tips are meant to provide some advice on how we might reduce our energy usage and absolutely not intended to trivialize the issue of fuel poverty, something we take very seriously,” he told the Independent.

But Labour’s shadow energy minister Tom Greartex said the advice was an “insult” to millions of people in the UK who are struggling to pay their bills.

“Rising energy bills aren’t a laughing matter and cause genuine hardship for millions of people issuing ridiculous advice, however tongue in cheek, will insult and annoy many customers who are struggling to heat and power their homes this winter,” he said.