NZGA.

We deliver geothermal leadership by:

• Linking people and projects by promoting geothermal research and employment opportunities
• Serving as a forum for the exchange of quality and unbiased information
• Encouraging and supporting geothermal research
• Ensuring regular conversations between Government and industry
• Influencing decision making through informed and impartial advocacy into New Zealand’s geothermal legislation, policy and regulations
• Responding to enquiries from the public and international community and connecting the right information with the right people
• Future proofing the industry by engaging young talent and connecting with the new generation of geothermal specialists
• Collaborating with national and international governmental, institutional and private agencies for the sustainable development of geothermal resources.
• Growing expertise and building capacity by providing or sponsoring topical seminars, workshops and training opportunities
• Promoting good practice guidance
• Producing strategic papers to inform and better position the geothermal industry

Katie McLean - President
Senior Reservoir Engineer - Contact Energy

Katie is currently a reservoir engineer working for Contact Energy at Wairakei, New Zealand’s oldest geothermal power station. She is an engineer and a geologist by training, with an interest in renewable energy, and so naturally made the move to New Zealand to work in the geothermal industry.

Katie has a PhD in geothermal well testing from the University of Auckland. She has published papers on a range of reservoir engineering topics, and more recently on the subject of carbon emissions from geothermal. She has co-authored a textbook on geothermal well testing with Dr Sadiq Zarrouk, of the Geothermal Institute at the University of Auckland.

Mike Allen - Vice-President

As we all recognise, these are challenging times for the energy sector and the geothermal industry more broadly. While Mike have been associated with geothermal activities for more than 40 years, much of his experience has been in helping deliver New Zealand experience and expertise into international projects. The establishment of Geothermal New Zealand Inc (GEONZ) in 2012 provided a platform to explore a more substantial role for the NZ industry overseas: though this has had mixed results, Mike believes it continues to help maintain our position in a number of markets, reinforcing contacts at industry, project and government levels. He also has involvement in the broader renewable energy sector through IRENA and programmes for MFAT and can offer a pragmatic view of how geothermal fits within this wider sector.

Over the last 18 months Mike has had the opportunity to work closely with the New Zealand industry in putting together a national presence for the WGC and through these efforts we have strengthened the connection between NZGA and GEONZ. He has been impressed with the reinvigoration of NZGA activities that the current board has brought to bear and this will ensure strong support for the industry going forward. His interest in joining the board is to reinforce this renewed approach of the NZGA, offer his international commercial experience and connections and ensure that the membership continues to be provided with personal and business development opportunities as appropriate.

Leighton Taylor - Treasurer
Director - LT Engineering

Leighton’s professional experience to date has been undergraduate work experience on New Zealand’s steamfields; a Masters Thesis in low temperature geothermal binary plants; design work at MTL for overseas steamfields projects; attending and presenting at geothermal conferences on both geothermal generation and steamfield design.

Leighton is committed to the belief that geothermal energy will play a significant role in achieving New Zealand’s carbon neutral goal. To become a member of the NZGA board is an opportunity to contribute towards the development of the geothermal industry and to shape how geothermal fits into the carbon neutral future of New Zealand. Leighton brings both enthusiasm and experience to the NZGA board.

Samantha Alcaraz - Secretary
Geothermal Geology and Modelling Team Leader - GNS Science

Samantha is a geologist specialising in geomatics. With GNS Science since 2009, her technical role is focussed on integrating multi-disciplinary data to create geoscience and spatial models that support our understanding of the geothermal resources. She has the privilege of leading the Geothermal Geology and Modelling Team at GNS, a group of 10 passionate geothermal experts. They work on a wide range of geothermal projects, from high temperature geothermal resource assessment to direct use applications in New Zealand and internationally.

Samantha has been the Secretary of the New Zealand Geothermal Association during her first term on the Board (2020-2023) with a particular emphasis in the last couple of years on updating the Bylaws and preparing the Association to transition to the new Incorporated Societies Act 2022. She is also the Treasurer of the Asia-Western Pacific Regional Branch (AWPRB) of the International Geothermal Association (IGA) since 2018, and more recently the co-Executive Secretary of the International Energy Agency Geothermal (IEA Geothermal) since early 2023. Through these roles, Samantha brings a connection to our international colleagues and activities in Asia-Pacific, Europe and the United States.

Clare Baxter - Board Member
Customer Solutions Specialist, Energy - Seequent Limited
Representative - Women in Geothermal WING

A geologist by background Clare also has a Master of Energy, where her research focused on developing a natural state model of a field in the Azures. For the past 10 years, she has supported geothermal companies build out their subsurface modelling workflows. This has taken her around the globe, where in 2017 she focused on Europe, Africa and Middle East region. Clare returned to New Zealand in 2021, joining the New Zealand geothermal community and is based in Christchurch.

Clare is an active committee member in Women in Geothermal and was the UK WING Ambassador before serving the WING NZ team.

Aroha Campbell - Board Member
Tauhara North No.2 Trust

Aroha is the longest standing Trustee of 30 years with Tauhara North No.2 Trust – Matua Board and currently holds the internal position on the Financial Audit & Risk & Policy Sub-Committee; a director on the Kai Whenua (Food & Land), Charitable Company Limited, Rotokawa Joint Venture with partners Mercury and the Chair of Waiariki Woman’s Refuge.

During her 11 years as CEO for Tauhara North No2. Trust, a sound foundation has been established for the owners and descendants ensuring their mission “Kia mau ki te whenua” Hold fast to the land, “Whakamahia te whenua” Make use of the land “ Hei painga mo nga uri whakatipuranga” For the future generations. This korero was given to them by Aroha's grand uncle Tete Mihinui from her dad’s whakapapa and Nanny Kurupai Whata from her grandmother’s whakapapa.

Aroha is very passionate about giving back to the Marae within the rohe of Ngati Tahu – Whaoa, assisting in community Trusts at a governance level and providing strategic insight, support and advice for community and indigenous groups around the world looking to develop their own geothermal projects or wishing to collaborate with partners on geothermal developments. She gets excited in creating an environment when interacting and listening to people and motivating them to find solutions and seeing their satisfaction and smile.

Aroha believes as a board member she can offer a Maori point of view in geothermal and walk a parallel pathway with a professional acumen.

Nga mihi

Mason Jackson - Board Member
Associate - Mitchell Daysh

Ko Takitimu te waka
Ko Hikurangi te maunga
Ko Tukituki te awa
Ko Ngāti Kahungunu ko Ngāti Porou ōku iwi
Ko Mason Jackson tāku ingoa.

Mason is currently employed by Mitchell Daysh – a resource management and environmental planning consultancy with offices across the motu.

Mason studied earth sciences at the University of Waikato, and since graduating and entering the work force, has gained approximately 25 years of environmental management experience in New Zealand focused in the energy and regulatory sectors. More notably, he has been involved in, and led, multi-disciplinary teams on a number of large geothermal consenting and development projects for Mercury NZ and its predecessor company Mighty River Power through, what some people refer to as, New Zealand’s “geothermal renaissance” period. In this regard, among various renewable wind and geothermal developments, Mason was lucky enough to work alongside Tauhara North No.2 Trust in the consenting and development of the Ngā Awa Pūrua and Ngā Tamariki geothermal projects.

Mason has a strong interest in the earth sciences, and a particular passion for geothermal resources and their sustainable development. Mason is an experienced RMA practitioner and closely follows the myriad of RMA reforms occurring and being signaled for the near future. As a result of his work experiences and environmental interests, Mason has become acutely aware of the preciousness of our geothermal resources, and of the important role they play in New Zealand’s effort to decarbonize. Similarly, Mason is conscious of the associated challenges and opportunities that face the future of our geothermal taonga, especially in light of emerging national regulatory reforms and global climate change. Mason believes he can offer specific value to the NZGA in this dynamic space.

Jacqui Nelson - Board Member
Chief Development Officer - Contact Energy Limited

Jacqui has been with Contact Energy for over 15 years taking the role of Chief Development Officer in October 2021. As Chief Development Officer she has responsibility for the company’s development and demand growth activities aligned with its Contact26 strategy. Previously Jacqui has held a wide range of roles within Contact across finance, resource management, trading and most recently as Chief Generation Officer where she was responsible for the electricity Generation and Trading, and Sustainability functions of the business which deliver 80% of Contact’s EBITDAF.

Prior to her current role Jacqui has headed up trading, the land consenting and environment group and was Company Treasurer from 2004 to 2010. In the years before Contact she was Treasury Adviser at Airways for nine years and prior to that worked at ANZ Banking Group.

Her passions lie in the people she connects with. She takes great pleasure in creating an environment in which the people she interacts with are motivated to be their best selves and to add value. Jacqui has received a number of external awards recognising her work and capability including the 2019 US Energy Association - Women in Energy Feature for Exemplary Leadership and the 2018 US Energy Association Corporate Volunteer Award for her work with Ngati Tahu in helping the Masai in Kenya.

As well as being a Director on the NZGA, Jacqui is Chair and Trustee of the New Zealand Red Cross Foundation (appointed Chair Aug 2020).

Jaime Quinao - Board Member
Associate Geothermal Engineer - Jacobs

Jaime is currently the Senior Resources Engineer or Kaipuukaha for Ngati Tuwharetoa Geothermal Assets Ltd. (NTGA) in Kawerau, a world-leading geothermal energy supplier for industrial direct heat use. In his role at NTGA, he enjoys the challenges and opportunities at the intersection of resource management, steamfield operations, resource and environment sustainability, and stakeholder engagement in support of geothermal energy development in the Kawerau Industrial Complex.

Jaime has over 11 years of geothermal resource management and reservoir engineering experience, starting as a reservoir engineer at Chevron Geothermal fields in the Philippines in 2007. He joined the New Zealand geothermal community in 2010 as a reservoir engineer for Mercury and moved to NTGA in 2017 to pursue his interest in geothermal direct heat use. He completed a Bachelor of Science in Chemical Engineering at the University of the Philippines in 2007 and a Master of Engineering in Engineering Science at the University of Auckland in 2016, studying a framework for uncertainty analysis of geothermal numerical models.

Farrell Siega - Board Member
Geoscience Manager – Mercury NZ

Farrell has had 27 years of experience working in the geothermal industry, previously with Energy Development Corporation in the Philippines before coming to New Zealand in 2008 to join Mercury (formerly Mighty River Power) at the peak of its geothermal operation development in Kawerau, Rotokawa and Ngatamariki.

Farrell holds a Bachelor’s Degree in Chemical Engineering in the Philippines, a Post-graduate Diploma in Hydrology in Austria, and completed a Master of Business Administration degree in Australia and a Certified Associate in Project Management qualification in New Zealand.

Farrell is a dedicated geothermal professional with a great passion for fostering team development, promoting diversity in the workplace, and taking care of the well-being of people around him. During his time on the NZGA Board, he is keen to leverage his experience and passion to continue the success of the NZGA in promoting geothermal energy development in New Zealand and overseas, and in raising awareness of what it can offer to the wider community.

Sadiq Zarrouk - Board Member
Co-Director, Geothermal Institute - University of Auckland

Sadiq J. Zarrouk is an Associate Professor of Geothermal Engineering, Co-Director of the Geothermal Institute, and the course director for the Postgraduate Certificate in Geothermal Energy Technology at the Department of Engineering Science, The University of Auckland.

Sadiq has extended research and commercial field experience in geothermal and reservoir engineering with more than 25 years of experience in geothermal energy training and research. In 2007 Sadiq was instrumental in the restart of the geothermal training programme at the University of Auckland.

Sadiq has worked on 41 geothermal fields around the world. His role was to assess the resource, well targeting, analysis of the performance of wells and reservoir modelling. He participated in several due diligence projects included the geothermal engineering aspects of the field development (steam field equipment, flow measurements, two-phase flow, power stations equipment, heat exchangers and direct use). Sadiq also runs many professional training courses and has provided expert evidence on several occasions.

Sadiq has an applied approach to geothermal energy research with ongoing collaboration and joint publications with several universities and research institutions in Belgium, Germany, Iceland, Indonesia, Iran, USA, Canada, Japan, Kenya, Philippines and Australia with more than 150 publications in journals and conference proceedings, three patents and two books.

Sadiq is an elected member of the board of directors of the International Geothermal Association (IGA) 2013-2020 and the New Zealand Geothermal Association 2011-2017. He is a member of the organising committee of the New Zealand Geothermal Workshop (NZGW) since 2006 and an Associate Editor in Geothermics since 2020.

Kennie Tsui
NZGA CEO

Kennie Tsui joined the New Zealand Geothermal Association as Chief Executive Officer in July 2021. Prior to this, she was the Principal Analyst at the Climate Change Commission, and was heavily involved with developing the recent report “Ināia tonu nei: a low emissions future for Aotearoa”. Tabled in Parliament in June, this report provided recommendations to the Government on climate change action in New Zealand. She has also held previous positions at the Ministry for Business, Innovation and Employment. A chemical and process engineer by training, and also holding an MBA qualification, Kennie has a wealth of knowledge across the energy sector built during her professional roles and directorships, as well as strong working relationships with central government. She is based in Wellington, New Zealand.

Jess Bradley
NZGA Board Coordinator and Communications Lead

Jess joined the NZGA in early 2020, taking on both the administration and communications aspects of the organisation. Prior to that, she has worked in a number of roles, including hospitality, event management, marketing and maths tutoring. Her involvement in the geothermal sector quickly connected as being based in Rotorua and her passion for a world-class sustainable future for Aotearoa New Zealand.

Paul Bixley

Paul has been involved in the geothermal industry within New Zealand and internationally for almost 50 years, specialising in well testing and reservoir engineering. He has been closely involved with exploration, development and operations in many geothermal resources, particularly with reinjection of cooled process fluids which was untried technology when he began his geothermal career. Over the last few years he has maintained his professional interests working part-time with Contact Energy at Wairakei helping to retain their geothermal heritage and as Chairman of Craters of the Moon Charitable Trust.

Pat Brown

A chartered accountant specialising in strategic planning, geothermal energy development, financing and management, Pat was a founding partner of Strettons Accountants. In 1999 when the Tūaropaki Trust's Mokai station was completed, the Trust was the first indigenous group in the world to raise finance for such a project. Pat played a key part in securing the finance whilst ensuring that Tūaropaki's land assets were protected from financial risk. Pat sat on the NZGA Board from 2004 - 2009, including two years as treasurer. During this time he successfully guided the IRD towards updating their taxation rules regarding geothermal drilling, increasing investor confidence in geothermal exploration.

Pat Browne

Pat Browne joined the NZ Geological Survey in April 1967, working as a petrologist/ geologist mainly on the Broadlands/ Ohaaki geothermal project but also Kawerau, Tauhara, Wairakei, Kawah Kamojang and El Tatio. Patrick was appointed to the newly established Geothermal Institute at the University of Auckland in December 1978 where he taught geothermal geology from 1979 until 2003. Here, with Manfred Hochstein and Derek Freeston, later joined by Robert McKibben and ably supported by many visiting lecturers, he enjoyed teaching several hundred geothermal Diploma students, many of who successfully contributed to geothermal projects in their home countries. His research interests mostly related to hydrothermal alteration.

Aroha Campbell

Ko Aroha Campbell, QSM taku ingoa

I have lived my life around geothermal, whenua and whanau in the central north island, specifically in the rohe of Ngati Tahu, Ngati Whaoa. I am humble to be associated with three geothermal reservoirs namely Ohaki, Ngatamariki, Rotokawa and their activities. More recently I have the pleasure of contributing to the development of the Taheke project within Te Arawa.

Nga mihi

Brian Carey

Brian Carey is a Geothermal Resource Management Specialist with GNS Science where he has worked in an advisory capacity for the geothermal sector for over 10 years. Brian is trained as a mechanical engineer well versed in geothermal resource utilisation borne out of having spent 20 years of his career managing the geothermal reservoirs at Wairakei and Ohaaki. Part of his current work is as the Executive Secretary of the International Energy Agency Geothermal Group, comprising 15 members, who are fostering the uptake of geothermal energy technology across the globe. Brian has been actively involved in the Geoheat Strategy for Aotearoa NZ 2017 - 2030 initiative from its inception. The initiative is promoting the direct use of low carbon geothermal energy and the associated jobs with the enterprises that embrace for the benefit of the New Zealand.

Malcolm Grant

Malcolm Grant returned to NZ in 1974, after graduating from MIT. He joined the Department of Scientific and Industrial Research (DSIR), to work on geothermal and became what is now known as a reservoir engineer. He was senior author of “Geothermal Reservoir Engineering”, and became Geothermal Coordinator (head of DSIR geothermal program). There was a spell in management (GM NZ Met Service, CEO National Institute of Water and Atmospheric Research (NIWA)), before becoming a private consultant in 1994. In the following years he worked on every geothermal project in NZ except Taheke, working for developers, Māori Trusts and regulatory authorities; and many fields overseas. The overseas experience included being an expert witness in international arbitrations, and chairing an International Geothermal Association (IGA) subcommittee on resource assessment. He retired in 2018.

Colin Harvey

Colin Harvey holds a doctorate in low temperature geochemistry and clay mineralogy from Indiana University. Colin has been involved in geothermal exploration and development in over 30 countries since 1981. He initially held the role of Senior Geochemist with KRTA Ltd and subsequently with GENZL (PB Power NZ Ltd). Colin’s development of the methylene blue technique and use of mixed layer clays are now internationally well recognised techniques in the interpretation of various geophysical measurements. After several years on the faculty of Indiana University in the 1990's, Colin returned to New Zealand in 2002 to lead the geothermal team at GNS Science before retiring in 2012. He was President of NZGA between 2004 and 2010, as well as serving on the IGA board for ten years with three years as Vice President. Colin is now retired from geothermal apart from an ongoing involvement in Peer Review Panels at Ohaaki and Ngatamariki.

Manfred Hochstein

Born in Germany, Manfred Hochstein graduated from Geophysics, Geology and Physics studies in 1961 and continued with post-graduate studies in the US and Antarctica until 1964 when he joined the Department of Scientific and Industrial Research (DSIR) in Wellington. He was superintendent of the Geophysical Survey, Geophysics Division (DSIR) from 1967 to 1972, and in 1973 moved to University of Auckland to teach Applied Geophysics. In 1978 he was one of the founding members of the Geothermal Institute based at the University, along with Pat Browne and Derek Freeston. Manfred was invited as a consultant to participate in several UNDP geothermal projects (Chile, El Salvador, Nicaragua, Kenya, Ethiopia, and PR of China) between 1967 and 1988, and later in several bilateral aid projects in Indonesia. Many of his students are now leaders in geothermal exploration in many parts of the world, and he had a pioneering role in the exploration and evaluation of numerous geothermal prospects around the globe. Manfred retired in 1997 but remained active in field explorations around the world, often supporting his past students with a variety of geothermal evaluations and resource inventory.

Trevor Hunt

Trevor joined the Geophysics Division of the Department of Scientific & Industrial Research, New Zealand in 1966. While there, he obtained his PhD from Victoria University in 1976. Although he officially retired in 2002, he has continued his scientific work as an emeritus scientist with GNS Science. Trevor pioneered the use of repeat gravity surveys to monitor mass balance for the Wairakei Geothermal Field. His first paper on the subject was published in 1970. The technique has since been applied to numerous geothermal fields in New Zealand, Japan, the USA, the Philippines, and elsewhere. Between 1994 and 2009, Trevor edited four special issues of Geothermics on geothermal systems in New Zealand. Trevor was a founding member of the International Energy Agency’s Geothermal Implementing Agreement, and was one of the leaders for the task called Discharge and Reinjection Problems. Trevor has also been very active in the International Geothermal Association. He was a member of the IGA Board of Directors from 1993 to 2001. He served as chairman of the IGA’s Technical Program Committee for WGC 2000 and as chairman of the Publication & Information Committee for the 2005 World Geothermal Congress. He served on the Board of Studies of the Geothermal Institute. Trevor was a founding member of the NZGA in 1992 and served until 1998.

Jim Lawless

Jim Lawless (BSc, MSc, Dip Teach) has a background of over 40 years of experience in geothermal energy. He has worked as a consultant to governments, international development agencies including World Bank, Asia Development Bank and the large German agency KfW, as well as many private energy companies. His first geothermal position was with the Department of Scientific and Industrial Research (DSIR), which led to a 29 career with scientific and engineering consultancy KRTA (later SKM). In 2010 he set up as a private consultant.

In later years his attention has mainly been on energy economics and policy. He is a Director of Polaris Renewable Energy, a Canadian-based international energy company. More recently, he has been voluntarily teaching environmental science to elementary school pupils, and has set up a certified tree-planting carbon offset scheme for travel with them. His intention (so far unrealised) is to retire at the end of 2022.

Jim has received awards and accolades for his contributions to geothermal, and has had numerous roles within the geothermal community, including chairing the NZGA Board from 2001 - 2004. He is an active member of the humanitarian organisation Oneness-Heart-Tears and Smiles and has been responsible for successful projects in Bali, Nicaragua, Tonga, Myanmar, Burundi and the Maldives.

Ed Mroczek

I joined Chemistry Division of the Department of Scientific and Industrial Research in 1986 after completing a PhD in high temperature solution chemistry. It was my privilege to be part of what was a groundbreaking period in New Zealand geothermal chemistry. I was able to be involved in the application of laboratory experiments and the advance of computing to the understanding of the thermodynamics of high temperature geothermal fluids and the hydrology of geothermal fields. Being based at Wairakei meant that I had the best mix of both laboratory and field work for over 30 years.

During this time I found that working in close association and collaboration with both developers, regulatory agencies and Māori Trusts was essential for understanding the problems that required applied research for their solution and I was very grateful for the support GNS Science received from them for grant applications over many years.

This collaboration with diverse industry groups was strengthened with them all coming together in the incorporation of the NZGA in 1992. I served on the Board and then as Secretary from 2001 to 2004. By the end of my tenure, I was gratified to have seen an explosion of interest in geothermal development and in membership of the Association. A series of dry winters at that time had shown the great value of an indigenous, renewable, low carbon fuel – a fuel that was not reliant on climate, as the generation of hydroelectricity is. Not much has changed in the intervening years and more dry winters mean that this commitment to the promotion of geothermal has proved itself to be more important and relevant today than it was back in the 2000s.
During my career I have gained immensely from working with countless colleagues from many disciplines and have thoroughly enjoyed my role in teaching and working with students from all over the world.
Ngā mihi.

Mike O'Sullivan

Mike O’Sullivan is a professor in the Department of Engineering Science at the University of Auckland, specialising in computer modelling of geothermal fields. He has written many papers on the subject and has taught courses on reservoir engineering and reservoir modelling at the Geothermal Institute and at various overseas universities and companies. Since the 1980's Mike has been involved in many commercial modelling studies in New Zealand and overseas, including modelling studies of Wairakei and Ohaaki in collaboration with Contact Energy Limited. He was responsible for the revival of the Geothermal Institute in 2007.

Past NZGA Life Members

- Dick Bolton

- Derek Freeston

- Dick Glover

- Russell James

- Brian Jones

- Tony Mahon

- Basil Stilwell

- Ian Thain

The NZGA was formed following a meeting of a group of geothermalists at the Geothermal Institute of the University of Auckland in October 1992. This group wanted to bring the geothermal industry together to promote and advance geothermal in New Zealand and connect internationally.

Some of this group had also been responsible for formation of the International Geothermal Association (IGA), which had been formed after a meeting of geothermal industry representatives at Wairakei on 14 October 1986; it was incorporated in New Zealand on 21 July 1988, with Prof. Derek Freeston as Secretary and remains registered as an Incorporated Society in New Zealand.

The inaugural meeting of the NZGA was held at the Geothermal Institute of the University of Auckland on 3 November 1992. At the meeting IGA affiliation and Incorporation of the NZGA were presented followed by planning of future activities:

A mid-year (1989) Wairakei seminar
The Geothermal Workshop preparations for 10-12 November 1993
Participation in the 1995 World Geothermal Congress

The original Board was:

• Ian Thain – President
• Derek Freeston – Secretary
• Tony Mahon – Vice President
• Neville Dench
• Tom King
• Arnold Watson
• Jim McLeod
• Trevor Hunt

The NZGA was incorporated in New Zealand on 21st October 1992; it was Affiliated with the IGA at the same time.

Meeting of geothermalists at Wairakei in 1988; the meeting that led to formation of the IGA and subsequently NZGA

Records are available from the Societies website from 1992. The first record is a change of the Bylaws; these were in fact the original Bylaws.

The NZGA is a not-for-profit voluntary organisation, chartered as an incorporated society.

The Association consists of our members, the Board of Directors (including the president, vice president, treasurer and secretary), our chief executive and administrative staff. The Board of Directors governs the affairs of the Association, and is elected at its Annual meeting.

Committees may be established to progress matters of interest to the Association.

The NZGA is an affiliated member of the BusinessNZ Energy Council (BEC).

NZGA Bylaws (last updated in November 2023)