ATHENS (Reuters) - Greece’s biggest electricity utility Public Power Corp. (PPC) posted a wider loss on Friday for the first quarter, as higher costs for carbon emission rights and the sale of power to alternative producers at below-cost prices were hurting profit.

PPC, with 77% of the domestic retail market, is seen as being key to the country’s energy security. A large loss it reported for 2018 and about 2.4 billion euros of arrears from unpaid bills accumulated during the Greek debt crisis have raised concerns over its finances.

The utility, which is 51 percent state owned, reported a net loss of 205 million euros (184 million pounds) for the first three months of the year versus a loss of 12.6 million euros for the same period last year.

Under a post-bailout arrangement with its lenders to help open up the electricity market, PPC needs to sell specific quantities of power to alternative producers at below-cost prices.

PPC’s shares plunged last week after a media report said the utility was in need of fresh funds to avert banks from calling in loans.

But chief executive Manolis Panagiotakis said on Thursday that the utility is not collapsing and that its problems can be addressed.

“First quarter 2019 financial results, following the respective figures for Q4 2018, reflect the negative

impact of exogenous factors, beyond the control of the Company”, Panagiotakis said in a statement.

He said that PPC will take additional actions to collect its arrears “in the next few days”.