Power company Genesis Energy says demand is expected to remain weak until the end of the year, with a modest improvement the year after.
In its annual Statement of Intent, which sets out priorities over the next few years, Genesis says newer, cheaper thermal plants will displace some units at its coal-fired Huntly Power Station.
Genesis has reiterated it will shut down one of its four older units at Huntly from the end of November.
A second unit is likely to be put into storage at the end of 2014 unless demand changes.
Meanwhile, the publicly-owned company will spend more than $125 million repairing the leaking Tekapo hydro canal over the next couple of years.
The first of two 14-week tranches of work is expected to start early next year and the second at the same time the year after.
Genesis made an annual profit of $90 million and expects to improve on that due to lifting power prices.