"It feels like we have got a clear playing field going forward to put significant focus into this, so it feels good," he said.
The other big players - Meridian, Genesis, Contact and Mercury - all have big retail businesses attached to their power generation activities.
"The (generator/retail) model is an interesting one but we felt that we wanted to be fully focused on developing capacity moving forward, without the potential distraction of having a retail business.
"We are very pleased to have had the retail business - we have put a lot of hard work into it - and we are delighted about the value that Mercury saw in it."
Being the odd man out would enable Manawa to focus more on renewable energy as New Zealand decarbonises.
"The other rationale was that with retail there was no doubt, from my perspective, that retail is a very hard game."
The company's retail arm had reached a point where it needed significantly more investment to take it to the next level.
Prentice added that retail had become an "increasingly competitive" marketplace.
In its result, Manawa said a financial derivatives gain hoisted its net profit to $119.8m in the March year.
The $30.7m improvement was largely due to a non-cash fair value gain on financial instruments in addition to increases in generation production and wholesale prices.
The company announced a final dividend of 16 cents per share and a one-off special dividend of 35 cents per share, unimputed.
Operating earnings (ebitdaf) were $204.2m (including the divested retail operations), up from $200.2m last year.
Manawa said it managed to deliver a solid performance.
Retail operations were in strong shape to hand over to Mercury, contributing operating earnings (ebitdaf) of $44.5m.
Generation production volumes across both the North and South Islands were 1760 gigawatt hours - an increase of 3 per cent on last year.
Inflows were up on 2021's record low, although they remained materially lower than average.
Manawa's work on asset investment delivered additional output which also contributed to the 52 GWh gain on last year.
Projects included major maintenance and asset renewals at Waipori, the installation of a new generating unit runner at Coleridge, and a new infiltration gallery intake at Branch River that when completed will yield an additional 10 GWh a year.
Prentice said Manawa would play a key role in New Zealand's energy sustainability.
"Over 99 per cent of our existing generation is renewable, and we have more in the pipeline."
Chair Paul Ridley-Smith Manawa had been able to reward investors with a special dividend while reserving some capital to enable growth and generate longer-term returns.
Manawa expects 2023 ebitdaf to be in the range of $140m to $160m and capital expenditure to be in the range of $45m to $55m.
