Ngāwhā Generation Ltd – Zero Carbon Electricity for the Far North

Winner of the Environmental action in industry and Environmental action to address climate change awards at the 2023 Whakamānawa ā Taiao – Environmental Awards.

Ngāwhā Generation Ltd (NGL), a geothermal energy company in the Far North that is on track to be New Zealand’s first zero carbon power station by the end of 2023, is a double award-winner this year.

In 2022, NGL transitioned from being one of the highest-emitting geothermal power stations in New Zealand to one of the lowest.

To achieve this, the company developed new technology to reinject 100% of the non-condensable gases extracted during electricity production back underground to the geothermal reservoir they came from, instead of releasing them into the environment. This creates a secure, closed-loop carbon zero system.

To develop the system, the NGL operational team worked in an international partnership to develop and trial innovative reinjection technology and methodology.

Initial experiments were carried out at Station One and then rolled out to Station Two. The system worked well, removing 35,000 tonnes of carbon dioxide from the atmosphere, and emissions from both stations ceased permanently in January 2023.

As a result, NGL is now producing zero greenhouse gas emissions from all but one of its three power stations. The remaining emissions, from Station Three, will cease in September this year. From then on, NGL will return 128,000 tonnes of carbon dioxide to the geothermal field every year.

Converting Stations One and Two to the zero-emission system cost $350,000 and took seven months, with the project wrapping up three years ahead of NGL’s target 2026 completion date.

The low cost of implementing the project contrasts impressively with its economic benefits. NGL has saved $5 million in carbon credits, a figure that is expected to rise to $10 million a year once the system is fully rolled out.

As well as reducing emissions, returning gases underground maintains the geothermal resource for future generations and gives consumers access to a reliable and affordable energy source.

Cultural significance and environment protection is honoured with monitoring and advice from local hapū.

The project supports Far North businesses and communities in the transition to a low carbon economy.

All electricity consumed on the Top Energy network during export periods will become carbon neutral once Station Three achieves zero emissions.

The success at Ngāwhā is inspiring change across the geothermal energy sector. NGL shares its insights with other geothermal generators to help the sector contribute to a carbon zero future for Aotearoa. The technology has potential to be applied around the world, representing a huge success for Aotearoa and our planet.

Our future depends on finding innovate ways to combine industrial success with protecting our environment. This inspirational project by NGL lights the way for sustainable geothermal power generation by proving success in industry can go hand-in-hand with addressing climate change.

(Images: Wendy Bown)