Staff at Ovo Energy have been told that around 1,700 jobs are set to be cut as part of plans which include reducing the number of offices from 10 to three.
Unions said they will oppose the job cuts, and criticised the UK Government for “doing nothing” to tackle the energy crisis.
The cuts represent a quarter of the number of employees at Ovo, which has around 4.5 million customers.
The company said it is also increasing its minimum wage by 15% to £12 an hour, giving a pay rise for 1,000 employees.
It will also reverse the policy of offshoring from the previous owner and create more high-skilled jobs in the UK, and open a new Ovo Academy in Glasgow.
Around 1,000 call centre staff will be trained to become zero-carbon living advisers, with specialist knowledge of green home products and technologies from tariffs to making homes more energy efficient.
The three remaining offices will be in Bristol, Glasgow and London, while more employees will be supported to work flexibly from home.
The company had to apologise earlier this week after an email sent to customers advised them to keep their heating bills low by “having a cuddle with your pets” or eating bowls of porridge.
The Unite union said it warned in 2020 that Ovo was taking a risk when it took over the retail base of Perth-based energy giant SSE.
Around 2,600 jobs were cut in May 2020 after Ovo closed offices in Glasgow and Selkirk.
General secretary Sharon Graham said: “We will not sit by and watch our members being made to pay the price of the pandemic.”
Unite national officer for energy Simon Coop added: “We warned the directors about blundering into the SSE takeover – in recent years the same directors have plundered the accounts for amounts estimated to be touching £5m.
“Ovo must be subject to severe scrutiny before the union decides on our next moves, but if they move to compulsory redundancies they will be fully opposed by the union.”
GMB national officer Gary Carter said: “At a time when more than 20 energy companies have gone to the wall and customers are looking to other providers for their energy needs, this looks like the wrong time to cut jobs.
“The government has stood back and done nothing to address the energy crisis and we are all paying the price.”
Unison’s head of energy Matt Lay said: “Instead of worrying about star jumps, porridge and cat cuddles, Ovo bosses should have been spending time on the issues that matter.
“Unions will be pushing managers to hold on to staff and retrain them – those in at-risk roles must become part of the huge energy-efficiency drive that’s necessary if net-zero commitments are to be met.”
Sue Ferns, deputy general secretary of the Prospect union, added: “The government needs to urgently look at wholesale reform of the energy retail market, including bringing it under local public control.
“We hope that Ovo is able to stick to its promise to limit losses to voluntary redundancy.”
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