Energy group Viridian moved back into the black last year, posting an after tax profit of €7.5 million, compared to a loss of €21.9 million the previous year.

The company, which owns electricity and gas suppliers Energia and Power NI, reported a turnover of €90.3 million for the 12 months to March 31st 2015. This is down from the previous year, when it recorded revenues of €132.1 million.

Operating profit at the firm, which operates two power plants in Huntstown, Co Dublin, increased from to €18.8 million primarily due to improved margins associated with the bidding, and lower operating costs and the recovery of gas capacity costs. Viridian reported an operating loss of €13.1 million for the same period in 2014.

The accounts, filed with the Companies Registration Office, show Viridian’s operating costs fell from €21 million in 2014 to €17.1 million last year.

The company’s balance sheet as of 31 March 2015 showed net liabilities of €104.6 million.

The directors of the company paid dividends of €8 million during the year.

Belfast-based Viridian emerged as a holding company in 1998, after the 1993 privatisation of Northern Ireland Electricity.

Viridian has been for sale since early December with an estimated €1 billion price tag, when its Bahraini owner, Arcapita Bank, sought bids for it.

The owners of Bord Gáis Energy and Airtricity are thought to be in the race to buy Viridian after submitting first-round offers for the business.