But retail electricity sales fell 11 per cent through relatively warm weather limiting demand and a strategy of reducing marginally priced commercial sales.
Generation fell 14 per cent as an abundance of water in the hydro lakes kept wholesale prices low and thermal plant, especially the coal-fired units at Huntly, uncompetitive much of the time.
"At times it was cheaper to purchase from the spot market than run thermal generation and thermal output declined 24 per cent, partially offset by an 18 per cent increase in renewable generation," said chief executive Albert Brantley.
Late in the financial year Genesis' renewable portfolio was boosted by the $821 million purchase of the Tekapo A and B power stations from its brother SOE, Meridian.
Last month the company said it had to write down the value of the Tekapo hydro scheme by $101 million soon after the deal was done to account for repairs to parts of the 25km canal linking the two power stations, which also require work.
These factors led to a bottom line loss of $16.6 million, after a profit of $69.3 million the previous year.