The country's largest power company, Genesis Energy, is easing off its plan to stop using coal completely by 2030.
Genesis owns the gas and coal-powered Huntly Power Station as well as wind and hydro stations. 60 percent of its generation is renewable, while the rest is thermal.
Huntly is used as a back-up for when the industry faces challenging weather conditions and was relied on heavily last year when power prices hit a seven-year high.
In February last year, Genesis announced an ambitious target to rid of the coal-fired units at Huntly, but chief executive Marc England is now wavering on that goal.
"Our intent is to remove coal by 2030 if we can."
However, in its submission to the Ministry for the Environment on the Zero Carbon Bill in July last year, Genesis said it intended to "exit coal-fired generation altogether by 2030 at the latest".
Responding to the change in wording, Mr England said the company did not rely heavily on coal.
"Remember we use a lot of gas in our thermal generation. Coal is a very small portion of the overall mix in New Zealand."
He said Huntly could operate solely on gas.
"We will still need some back-up, and that back-up will need to be there when the wind is not blowing and the lakes are low. We expect that back-up to continue to play a role into the 2030s."
Genesis' goal to only use coal in exceptional circumstances from 2025 remained.