New Zealand could become a renewable energy super power capable of powering all manner of energy intensive export-earning enterprises.

"The amount of investment, which is going on at pace, is an exciting opportunity, and as a nation, it's just a matter of whether we can seize that or not," Contact Energy chief executive Mike Fuge said.

"We are 90- to 95 percent renewable, heading to 98 percent with almost all of the firming provided from renewable sources."

He said the collapse of the gas supply was the past, as New Zealand continued to build large scale renewable energy, which could provide the firming, or back-up energy reserve of last resort.

Major Electricity Users' Group (MEUG) chairman John Harbord said there was still a dry-year risk regardless of how much renewable energy was generated.