PROFITS at Power NI's parent company Viridian Group rocketed by 42.1 per cent last year to £106.3 million before exceptional items.
Revenue however fell to £1,46 billion in the 12 months to March 2015 from £1.6bn the previous year.
The group's annual report showed operating profit at Power NI rose 16 per cent to £26m.
Sales at Power NI actually reduced to £420m from £458.3m "primarily due to the reduction in residential customer numbers together with lower consumption per customer and lower market prices" the report said.
However, this was partly offset by higher volumes of unregulated sales - those to larger energy users.
The company is reported to being offered by sale by its Bahraini owners Arcapita Bank BSC which are said to expect bids as much as £700 million for the group.
The Viridian Group which also operates Energia, a provider of gas and electricity to business customers across Ireland.
It is anticipated British energy giant Centrica will be interested. It bought Irish firm Bord Gáis Energy last year for €1.12 billion (£792m).
Arcapita filed for Chapter 11 protection in the US in 2012 after talks with creditors over a syndicated loan failed.
However, it exited bankruptcy a year later after securing a US$350m (£234m) loan from Goldman Sachs.
Last month Viridian announced it was creating 35 jobs over three years as part of a £20m investment in new IT systems.
