The company cited the strong performance of its wind farms and landfill gas operations, as well as lower overheads, as results came in ahead of expectations.
Turnover rose by 7.3 per cent to £242.5 million, and there was an 18.3 per cent rise in underlying EBITDA (earnings before interest, tax, depreciation and amortisation) to £148.4 million, before exceptional items.
But pe-tax earnings slid to £27.8 million for the year ended March 31, down from £2.9 million.
The accounts show the company narrowed net debt by 1.5 per cent to £555.6 million, and booked exceptional items of £39.4 million due to costs relating to the flotation and refinancing. Costs relating to the initial public offering came in at £37.1 million, which included fees of £16 million for external advisors, and bonuses for directors and staff.
Infinis, which aims to boost onshore wind capacity to between 130 mega-watts (MW) and 150 MW by 2017, consolidated its previous facilities for 10 separate wind farms totalling £255 million into a single £296 million syndicated loan.
Mr Marchant said the new facility has "significantly reduced complexity, increased flexibility and, most importantly, reduced interest costs".
Mr Marchant, who pocketed £655,000 in his final three months at SSE last year, praised staff at Infinis for delivering record results in the year it went public.
He said: "The flotation was achieved despite regulatory pressures and a difficult political backdrop.
"The political landscape around UK energy policy continues to be challenging but I believe that by focusing on affordable, reliable and clean electricity production, Infinis is well positioned for the coming years."
Meanwhile, the company said the forthcoming referendum on Scottish independence resulted in no change to its risk profile.
It noted the level of support for renewables in the event of a Yes vote was "unclear", and warned revenues from wind farms could fall given its exposure to the Scottish market.
But it pointed out the Scottish Government has "indicated its strong support for renewable energy", and added: "'RUK (remainder of UK) would still have obligations to meet its 2020 EU targets for renewable energy with Scotland being an obvious source given its strong wind resource."
Infinis is proposing a final dividend of 6.63p per share.
Shares in Infinis, which floated at £2.60 per share, closed up 9p at 237.5p.