Infratil is planning to complete its $65 million buyback of its own shares through a tender process on 22 October, rather than buying them over time as has been traditional.
Chief executive Marko Bogoievski says Infratil doesn't want the buyback process to drag on.
He says the process is quite innovative for New Zealand capital markets although it's more standard in markets such as the UK.
"It's not a bad idea if you've got a stock that's not that liquid and you are trying to introduce some efficiency in the buyback."
Mr Bogoievski says a lot of firms announce buybacks but then take a long time to execute them and Infratil wanted to avoid that.
He says after 14 March the Snowtown wind will be fully commissioned which will introduce a lot of new operating income to the group.
Mr Bogoievski says by 2017 what now looks like $500 million earnings before interest, taxes, depreciation and amortization (EBITDA) could extend to the $700 million level.
Infratil says it believes the share market is undervaluing its shares, which it says are worth between $3.08 and $3.69, although it will pay only a maximum price of $2.60 a share in the buyback.