Geo40, Contact Energy and the Ngati Tahu Tribal Lands Trust are teaming up as part of a world-leading sustainable energy project.

Set to start this month, the operation will see Geo40 use its technology to commercially extract silica from geothermal fluid used at Contact Energy's Ohaaki power station.

Up to 10,500 tonnes of high grade silica is expected to be sourced from Ohaaki each year, most of which will be exported overseas and sold to manufacturers for use in every day consumer goods.

John Lea, Geo40 chief executive, said the deal gives Geo40 access to a valuable mineral without harming the environment.


"Ohaaki's geothermal fluid enables us access to a valuable mineral without harming the environment," Lea said.

"The beauty of our technology is that nature – the geothermal reservoir – has already done most of the work for us, by dissolving the natural-occurring silica. Our process extracts the silica and turns it into silica products that will be exported around the world."

The partnership also significantly benefits Contact Energy and the Trust.

The removal of silica, which builds up over time, will significantly reduce equipment maintenance costs for Contact Energy and increase the overall life-span of the plant.

"Geothermal energy is a proven source of renewable energy and this partnership builds on geothermal's already impressive environmental credentials," James Kilty, chief generation officer at Contact Energy, said.

"It's part of our de-carbonisation strategy. Our focus is on using innovative ways to support customers to shift off carbon-intensive inputs by maximising the benefits of the abundant renewable resources in New Zealand."

The deal will not only provide an ongoing revenue stream to the Trust, but will restore clarity to the Ohaki Ngawha, a sacred natural hot spring.

"Our initial aim has been to support the Ohaki Marae Reservation Trust to improve the clarity of fluid supplied to the Ngawha, Marae protection from the Waikato River and re-establish the road from the Marae to the Ohaki Bridge, thereby connecting the Whanau that live along the Te Toke road," Aroha Campbell, a spokesperson for the Trust, said.

"We have strengthened our relationship with Contact Energy as an enabler to form new relationships, and we have already seen the benefit of whanau being employed by Geo40. We will see positive changes to our landscape over time while being fully in control of that destiny."


Silica is a naturally occurring and very common mineral (SiO2) and various forms of it are used in everyday materials and products, such as windows, paints, plastics and rubber.

Plans are already progressing on expanding the partnership.