* Eskom forecasts annual losses until 2022
* Utility seeks even higher power tariff hikes
* Firm supplies more than 90 percent of S.Africa's power (Adds bond moves)By Alexander WinningJOHANNESBURG, Feb 4 (Reuters) - South Africa's strugglingpower firm Eskom expects to make a wider 20 billion rand ($1.5billion) loss in the current financial year and wants steepertariff hikes than it previously sought, its chief financialofficer said on Monday.The chief executive also said the government should considerinjecting extra capital into state-owned Eskom to help it copewith what he said were low electricity tariffs.Eskom, which previously forecast a 15 billion rand loss inthe financial year ending in March, is vital to South Africa'seconomy because it supplies more than 90 percent of its powerbut is drowning in around 420 billion rand of debt.South African President Cyril Ramaphosa is trying to turnaround the ailing company and has said he will announce a planto shore up its finances in the coming weeks. Eskom's dollar-denominated bonds have rallied in recent dayson hopes that Ramaphosa will unveil a restructuring plan soon.On Monday, many issues fetched their highest since June2018. The 2025 issue rose 0.8 cent to trade at99.5 cents in the dollar and the 2023 bond nearly matched those gains to change hands at 99.45 cents,according to Tradeweb data.Chief Executive Phakamani Hadebe told a mining conference inCape Town the government should consider splitting the utility,using the term "functionally unbundling".Chief Financial Officer Calib Cassim said in Johannesburgthe larger forecast loss would be due to higher-than-anticipatedpower plant maintenance costs and increased use of diesel andgas, which is typically more costly than coal for generation.Cassim said Eskom was now requesting electricity tariffhikes of 17.1 percent in 2019/20, 15.4 percent in 2020/21 and15.5 percent in 2021/22, steeper than a previous application forincreases of 15.0 percent in each of those three years.Eskom said the new request was based on changes to its salesforecasts and production plans, arguing that significant timehad elapsed since it made its initial request.South Africa's energy regulator is expected to make adecision on Eskom's tariff request in March this year."We need Eskom to be sustainable to supply electricity,"Cassim told a public hearing on the tariff increases."We are using one credit card to pay for another," he said,saying Eskom was funding debt servicing with further borrowing.If granted the revised tariff hikes, Eskom would still turna profit only in 2022, Cassim said, showing the challenge facingthe firm. ($1 = 13.3404 rand) (Additional reporting by Wendell Roelf in Cape Town and KarinStrohecker in LondonEditing by James Macharia and Dale Hudson)