Harnessing geothermal heat

New Zealanders will have more opportunity to use heat energy drawn directly from the ground in the future, as a result of research led by GNS Science.

Over the next three years, the organisation will lead a research programme aimed at increasing the use of low temperature geothermal energy in New Zealand. Low temperature refers to geothermal heat sources that are generally less than 150ºC.

The main uses of low heat resources are heating for homes and offices, bathing, greenhouse heating and aquaculture. It is also used for food processing and other industrial applications.

Project leader Brain Carey says New Zealand’s landmass is a large source of heat, with different types of natural energy available for harnessing with the right technology in various locations.

“Low temperature geothermal resources are widespread throughout New Zealand and there is significant potential to increase their use. They are capable of providing long-term energy and heat supply with low carbon emissions,” Mr Carey says.

Natural heat energy sources include springs and borehole fluid discharges, water and steam from thermal power plants, warm water from oil and gas wells and flooded underground mines.

The benefits of harvesting energy this way include low environmental impacts and increased security of supply, Mr Carey explains.