(19 July 2018) - Geo40, in cooperation with Contact Energy and the Ngati Tahu Tribal Lands Trust, is this month set to
start commercially extracting silica from geothermal fluid as part of a world-leading sustainable energy partnership.
The operation will see Geo40 use its technology to extract silica from geothermal fluid used at Contact’s Ohaaki power
station.
Once extracted, the silica will be sold to manufacturers for use in everyday consumer goods, such as paint, providing an
environmentally-sound source of silica that would otherwise require amounts of carbon-intensive energy to make. The
potential volume of high grade silica that will be sourced from Ohaaki is up to 10,500 tonnes a year, most of which will
be exported overseas.
“Geothermal energy is a proven source of renewable energy and this partnership builds on geothermal’s already impressive
environmental credentials,” said James Kilty, Chief Generation Officer at Contact Energy.
“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 partnership offers clear benefits to all parties.
For Contact, the operational benefits are significant. Silica builds up in the geothermal pipes over time, and removing
the silica significantly reduces equipment maintenance costs and increases the overall life-span of the plant. Removing
silica also allows the plant to extract more heat from the geothermal fluid, making it more efficient to run.
The deal provides financial and social benefits to Ngati Tahu Tribal Lands Trust. The partnership will provide an
ongoing revenue stream to the Trust, and the processed fluid will restore clarity to the Ohaki Ngawha, a sacred natural
hot spring. This will be the Trust’s first commercial venture of this nature, with the proceeds going towards restoring
the Ohaki Community.
“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,” said Aroha Campbell, a spokesperson for the Trust.
“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.”
The benefit for Geo40 is the ability to access a source of silica that does not require the same level of heat
processing as silica sourced through traditional means.
“Ohaaki’s geothermal fluid enables us access to a valuable mineral without harming the environment,” said Geo40 Chief
Executive John Lea. “The beauty of our technology is that nature – the geothermal reservoir – has already done most of
the work for us, by dissolving the naturally occurring silica. Our process extracts the silica and turns it into silica
products that will be exported around the world”
There are also positive economic benefits for the Waikato and Bay of Plenty regions, since Geo40’s extraction and
processing plants will need to be situated close to geothermal fields, creating additional jobs in provincial New
Zealand.
Plans are already progressing on expanding the partnership, with the parties investigating the possibility of processing
up to 10 times as much fluid per day.
Notes to editor
· Silica is a naturally occurring and very common mineral (SiO2).
· Various forms of silica are used in everyday materials and products, such as windows, paints, plastics and rubber.
· Specialty silicas are otherwise produced by an environmentally unfriendly industrial process using strong chemicals
and a large amount of heat to dissolve and purify the silica.
· Silica is a natural by-product of geothermal energy generation – where nature’s heat dissolves the silica deep under
the ground in geothermal fluids.
· Contact and Geo40 have been running a pilot project to test the silica extraction technology with Contact Ohaaki
Plant’s equipment since October 2017.
· This commercial demonstration plant follows the pilot project’s success and will see Geo40 technology process
approximately 850 tonnes of Contact’s Ohaaki Plant geothermal fluid per day, to produce 460 tonnes of liquid colloidal
silica per annum.
· The next stage includes plans to process 6,000 tonnes of fluid per day and stage three will aim for 7,000 tonnes.
· The silica extracted will be supplied around the world to manufacturers of consumer goods, such as paint and golf
clubs.
· This is the first commercial demonstration plant of its kind in the world.
ends