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SSE has become the latest "big six" energy supplier to raise its prices.

It said average electricity prices would rise by 14.9% from 28 April for 2.8 million customers. However, it will keep its gas prices unchanged.

As a result, SSE said a typical dual fuel customer would see their annual bill rise by 6.9%, or £73.

It blamed the increase on government policies that mean customers subsidise energy from renewable sources and the cost of smart meter installation.

Other government-imposed costs include subsidising the feed-in tariff scheme for home owners that install solar panels on their roofs.

'Deep regret'

SSE said the electricity price rise was its first for three and half years.

Four of the other big six suppliers have already announced price rises this year, while British Gas has held prices until August.

Scottish Power 's standard electricity prices will increase by an average of 10.8% and gas by 4.7% on 31 March.

's standard electricity prices will increase by an average of 10.8% and gas by 4.7% on 31 March. Npower is raising its standard tariff electricity prices by 15% from 16 March, and gas prices by 4.8%

is raising its standard tariff electricity prices by 15% from 16 March, and gas prices by 4.8% EDF Energy cut its gas prices by 5.2% in January, but its electricity prices rose by 8.4% on 1 March

cut its gas prices by 5.2% in January, but its electricity prices rose by 8.4% on 1 March British Gas is freezing its gas and electricity prices until August

is freezing its gas and electricity prices until August E.On is increasing electricity prices by an average of 13.8%, and gas prices by 3.8%, on 26 April

Will Morris, SSE's managing director for retail, said he "deeply regretted" having to put prices up.

"This is the first increase since 2013 ... we have seen significant increases in electricity costs, which are outside our control," he said. "Without an increase we would have been supplying electricity to domestic customers at a loss."

Switching

SSE said that 85% of its customers were on its standard variable tariffs, so they will be affected by April's price rise.

Last December, industry regulator Ofgem published figures showing how much money customers could save by moving from a standard variable tariff to their supplier's cheapest fixed tariff. For SSE customers that was £98 a year.

Earlier this month the FTSE 100-listed company had to apologise to a number of customers whose smart meters had been reporting astonishingly high rogue readings for their electricity use.

Analysis: John Moylan, BBC industry correspondent

There are around 20 million customers on standard tariffs - mostly with one of the big suppliers.

With SSE's price rise, those customers now know how their bills will be hit in the months ahead.

Most will see price rises - that is a political headache for a government worried about families that are just about managing.

There has been speculation that ministers could intervene in the energy market, perhaps by extending the price cap coming in for pre-payment meter customers.

Citizens Advice want households that receive the government's Warm Home Discount scheme to be protected from price rises too.

Whether intervention is on the table should become clearer later this year when the government publishes its official response to the energy market investigation being undertaken by the Competition and Markets Authority.