Manchester residents have been left 'freezing or homeless' after their energy provider hiked prices as much as 300 percent.
The hugely inflated bills have hit people living at a block of flats in New Islington, in the centre of Manchester, after their previous supplier CNG Energy entered administration in November.
All residents in the building must use the same boiler and have the same energy supplier.
After CNG's collapse, Pozitive Energy, was appointed by the regulator Ofgem to take over their supply - but residents told the Manchester Evening News that has seen their monthly bills sky rocket.
When bills arrived in December, just days before Christmas, residents were being asked to pay triple, or even quadruple, previous amounts.
One bill went from £56.29 in August 2021 to £152.63 in December, another soared from £42.02 to £215.29 and another from £66.70 to £260.56.
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The letters have sparked uproar in the building where there is a mixture of renters and owner-occupiers.
Jeff Swales, 35, said: "I don't think they appreciate the effect that letter has had just before Christmas - it was devastating.
"There was one woman who's got a £300 bill, she was sat in the lobby in tears saying 'I don't know how I'm going to pay'.
"I took out a payday loan to cover it and now I'm moving out.
"I'm going to sleep on a friend's sofa."
Jeff, an IT professional, is one of a number of tenants who moved into the Chips building on a Rent to Buy scheme.
The scheme means eligible renters pay 80 percent of market rate so they can save 20 percent towards a future deposit.
But tenants say the energy price hike means it no longer makes financial sense to live there.
Luke Ives, 30, who is also on the Rent to Buy scheme, said: "That 20 per cent isn't going towards a mortgage, it's going towards energy bills.
"People are leaving because it's unaffordable."
In the meantime, residents have told of being too scared to turn on the heating or even have hot showers.
"I've got a plug-in oil heater," said Luke, who works in engineering.
"I don't want a £300 bill.
"If it's cold we just put extra layers on."
Adam Labatt, 34, another Rent to Buy tenant, added: "This winter I'm just not using it [the heating].
"It's absolutely freezing, a lot of us work from home all the time but we're scared to put the heating on.
"Part of living here was to save - especially as a single person - so that I could get my own property, that's what attracted me.
"I can't do that when I've got these bills.
"I'm cutting back on other things - it might be deciding not to go out or not doing a big food shop."
Tenants are dealing with multiple parties including Urban Splash, the property management company RMG and the company which manages the billing of the 'district' heating system, Switch2.
As well as being celebrated for its unique architecture, much was made of its eco-friendly features including a 'green' heating system designed to generate electricity while capturing heat made in the process.
It means all residents operate off the same boiler and are therefore locked in with the same energy supplier.
Current residents say the situation has deteriorated with spells as long as three months without heating or hot water during recent winters.
This is disputed by RMG who say the boiler has never failed for more than 24 hours since it was replaced in 2017.
In a post on its website about the CHIPS building, Switch 2 acknowledged the historic issues and described how the firm was brought in by Urban Splash to 'improve both system’s efficiencies and the heat supply to its residents.'
The boiler needed to be replaced as it was 'damaged and not operating effectively for residents', the post says.
Residents 'stopped paying their bills' and the heating scheme began to accrue debt, it adds.
The project to replace the boiler and take over metering and billing reduced pre-existing debt by 68 percent, Switch2 claimed.
But it appears these problems have continued and residents now feel trapped by the arrangement that keeps them locked in with one supplier.
"The worst of it is that we can't change provider," said Adam.
"Or we would shop around. But we're stuck, we can't do anything, it's like it or lump it."
Magdalena Mikulak, whose bill went from £80 a month to £260 for December, added: "I always assumed the bills were high already, now they've just gone through the roof, I don't know how it's sustainable.
"And it's not even warm, I'm just using the heating enough to not be cold, not to freeze to death.
"People are moving out because of it."
A Switch2 spokesperson said: "Switch2 Energy is the billing service provider for the Chips scheme and is not responsible for the operation and maintenance. Therefore, we can only comment on the metering and billing and why the tariff has increased.
"Switch2 provides billing services for New Islington Utilities. The energy supplier for the site, CNG, went into administration in November and Ofgem allocated a Supplier of Last Resort to step in.
"The new tariff reflects the market increases experienced over the last 12 months, which have seen the wholesale gas price increase 5-fold since January 2021.
"In line with every other domestic consumer who will be, or currently are, facing a significant price increase, the charges for heating and energy will be rising at Chips.
"We understand the annual energy bill for gas and electricity at Chips to be going up by 47 percent.
"Generally, the bills customers receive include a heat unit charge based on their meter readings.
"This covers the cost of gas and electricity used in the communal heating system plant room. There is also a daily standing charge. This covers the cost of maintaining and repairing the plant (boilers, pumps, distribution pipe work, meters and heat interface units) and billing activities."
RMG operations director Justin Herbert said: "There has been historic problems with the boiler system at Chips but the developer provided an additional boiler in 2017 at no cost to the leaseholders and since then the boiler system has not failed for more than 24 hours. The last failure was in October 2021 but this was addressed on the day.
"Communal boilers heat the hot water and the water pumps, pump the hot water around the building.
"RMG currently maintain the communal parts of the heating system.
"There are currently no known faults with the communal system and both boilers are working efficiently.
"RMG have no involvement in the procurement or placement of utilities contracts or the billing but sympathise with the increased costs the residents at Chips and across the country are now facing.
"In terms of the cladding situation, the safety of the residents has been the priority since we identified the issue and we have taken advice throughout from fire engineers, surveyors, and Greater Manchester Fire Service with all parties satisfied that we have taken the short term remedial action required. This saw the implementation of an integrated fire alarm system."
Plumlife director of private sector management Caroline Millington said: “We sympathise with our customers regarding the energy tariff increase as this is an issue being experienced across the board.
"We are seeking clarification on behalf of our customers as neither the maintenance of the heating system nor the choice of the energy supplier in under our control.”
Urban Splash declined to comment.
