Perth-based energy giant SSE said it would increase its electricity prices 14.9% on average from April 28 in a move that would affect 2.8 million customers throughout Great Britain.
SSE will hold its gas prices at their current level.
The company said the change equates to a £73 or 6.9% rise per year for a typical dual fuel customer.
“The 6.9% dual fuel increase will mean a typical domestic customer will pay on average £73 a year more, which equates to around £1.40 per week, as a result of an average 14.9% increase in electricity prices,” said SSE.
“The new typical dual fuel bill of £1,142 per year remains cheaper than in November 2013 and gas prices remain the cheapest they’ve been since October 2012, thanks to three price cuts in the intervening period …
“The price change reflects the increasing cost of supplying electricity, and specifically higher costs associated with delivering vital government programmes designed to upgrade Britain’s ageing energy infrastructure and help the country move towards a low carbon future.
“These costs are levied predominantly against electricity customers.”
Will Morris, SSE managing director for retail said: “We deeply regret having to raise electricity prices.
“This is the first increase since 2013 and we’ve worked hard to keep them down for as long as possible by cutting our own costs, putting in place a winter price freeze and holding gas prices, but we have seen significant increases in electricity costs which are outside our control.
“Without an increase we would have been supplying electricity to domestic customers at a loss.
“We know that any increase can add extra pressure on customers’ bills so we’re launching a £5 million fund to provide assistance to those who are struggling with their bills, in addition to the existing £46 million that SSE already spends helping customers through the Warm Home Discount.
“Anyone worried should contact our advisors so we can ensure they benefit from any support available to them.”