He went from Tiwai Point — New Zealand’s largest consumer of electricity — to chief executive of Mercury NZ, one of New Zealand’s largest creators of electricity.
Mr Hamilton returned to his old stomping ground of Southland last week for an Institute of Directors’ Otago-Southland branch event, attended by more than 40 people.
He joined New Zealand’s Aluminium Smelter (NZAS) 25 years ago as a graduate engineer, and later became the boss of the aluminium smelter before leaving in 2021 to become general manager of generation at Mercury. He was appointed chief executive in September this year.
Mr Hamilton said he still cared deeply about Tiwai and, with the smelter becoming Mercury’s largest customer, it was “kind of full circle” for him.
The Kaiwera Downs wind farm development in Southland, of which stage two is under construction, was largely linked to the smelter, he said.
The second stage involved a $486 million investment with the first generation expected in mid-2026 and full generation expected at the end of that year from 36 turbines. It was largely about building roads and more like a civil project. but that would change next year when blades were on site.
The chimney at Tiwai was 135m high and probably the tallest structure in the South Island. Once the turbines at Kaiwera Downs were built, they would be 160m high and the tallest structures in the South Island — a “pretty impressive engineering feat”, he said.
Speaking to some of the big global wind turbine manufacturers, they mentioned how New Zealand had some of the best resource — or wind — in the world and they got excited about what could be built here.
Mr Hamilton said New Zealand was facing significant change; rising cost of living, rapid technology change and AI development, different generational expectations, climate change, geopolitical tensions and challenges to democracy, and changing societal norms.
Transitioning to zero carbon could be “pretty bumpy” in many ways and the energy sector faced a “trilemma”.
By its very nature, renewable energy “goes up and down” — either the wind did not blow, the sun did not shine or the rain did not fall — and consumers required reliable and affordable energy at the push of a switch. The big headwind for the industry was how to manage when New Zealand, which was so dominated by hydro power, experienced dry periods.
Mercury has about $1 billion worth of renewable generation development under way and that was one of Mr Hamilton’s highlights for the year, saying it would be of huge benefit to New Zealand. Some of the good things happening in the sector could get “lost in the noise”, he said.
Mercury was looking at how it could engage in the Energy Competition Task Force with the Commerce Commission and to be part of the solution, he said.
