The energy cap is set to rise by 80% in October, it was announced this week.
Further rises are feared to be on the horizon in January and April next year.
MoneySavingExpert Martin Lewis has called for more action from the government to support people through the price rises.
Here is what has been said:
How much is the cap increasing by?
Ofgem has confirmed an 80.06% rise in the energy price cap, sending the average household’s yearly bill from £1,971 to £3,549 from October.
The cap will come into effect for around 24 million households in England, Scotland and Wales on default energy tariffs on October 1, and will remain in place until December 31, when it will be adjusted again.
However, Ofgem warned that some suppliers could start to increase direct debits before October 1 to spread costs.
What has Martin Lewis said?
Mr Lewis told BBC Radio 4’s Today Programme: “I’ve been accused of catastrophising over this situation.
“Well, the reason I have catastrophised is this is a catastrophe, plain and simple.
“If we do not get further government intervention on top of what was announced in May, lives will be lost this winter.”
The 4.5 million pre-payment meter customers, who are often the most vulnerable and already in fuel poverty, will see their average annual bill rise to £3,608.
However, Mr Lewis said many will likely pay much more.
He said: “You could easily be paying £5,000 or £10,000 a year if you have high usage.
“I worry terribly for some of those who have disabled children or disabilities themselves who need lots of electrical equipment to keep their houses warm because of medical conditions.”
Mr Lewis said prices for many will be “unaffordable” in January.
He added: “The prediction now in January is up another 51% on top of where we are now and that would take a typical bill and direct debit to £5,386 a year.”
What is Martin Lewis’ bill calculator?
In a post on Twitter, he said that his MoneySavingExpert team has created a calculator to help users work out how much their bills will increase by.
The calculator is on the MSE website.
What advice has he given the government?
On Twitter, Martin Lewis wrote: “These rates are mathematically unaffordable for many.
“The full new state pension is £9,600/yr, the older one £7,400/yr, and remember many pensioners have higher than typical use. Bills are an even bigger proportion for many on benefits and with disabilities.
“If not the physical and mental health risk to millions is unthinkable.
“And if the package is right, as I did in May, I’ll be the first to applaud. Please help.”
What has he said about the Don’t Pay movement?
Mr Lewis said a movement to refuse to pay energy bills is “growing”, as he called on the next prime minister to spend billions on tackling the crisis.
He said: “We must hope that once we have somebody in place, they will come up with a robust strong policy that we can all get behind that feeds people and heats people so we don’t have people dying because of these price cuts these winters.”
The money saving expert added: “I suspect if it isn’t in place, then people coming from the Don’t Pay movement are going to become a louder voice in this country.”