Business Central February 2021

44 | Geothermal - just ticking along in the background from page 42 Phone: 03 983 5500 waterfordpress.co.nz Find new clients with regular marketing in print media ADVERTISING IS GREAT FOR BUSINESS ENERGY Contact Energy “From those five geothermal sites we have total generation capacity to produce 430 megawatts. The plants run pretty much 24/7, barring maintenance and outages, so the plants generate quite a lot of energy.” Geothermal tends to run baseload, which is in the background all the time, producing about 3300 gigawatt hours of electricity annu- ally from those plants. On average, at any one time, Contact’s geo- thermal output might power 400,000 homes. In context, according to the 2018 census there are20,682 private dwellings in Taupo, so there is a massive amount of energy generat- ed from geothermal fluids available for other parts of the country. Inclusive of Contact, Mercury and other energy producers, geothermal provides about 17% of New Zealand’s electricity and most of that comes from the Central North Island. Within the global geothermal picture New Zealand ranks the 5th largest supplier of geo- thermal energy — massive when you consider the size of the country. The United States is the highest. The dominant use of geothermal energy is the production of electricity but Contact also provides customers in Taupo and Ohaaki with steam for industrial use. Tenon Ltd, a wood-processing mill in Taupo, switched from natural gas in their timber drying kilns to geothermal in 2006 and is currently Contact’s biggest user of direct use geothermal energy. At that same location Nature’s Flame dries wood pellets for wood burning stoves and furnaces. Their alternative was to use natural gas or burn some of their own product in the kilns. But by using geothermal fuel they can produce more wood pellets. “We also supply Ohaaki Thermal Kilns with heat. They produce kiln-dried firewood and we’ve supplied the Huka Prawn Park with heat for many years. Then there’s use for bathing and tourism activities. Wairakei Terraces has a bathing complex that uses geothermal water supplied by us that cascades down some silica terraces and into pools that people bath in. The heat is also used for heating the build- ings and swimming pool at Waikarei Resort.” Innovative company Geo40 Limited has based its plant in Ohaaki to recover silica from the geothermal fluids from Contact’s wells during the reinjection process. “In compar- ison to other ways that silica is produced around the world it’s a very benign way of ac- cessing the minerals because nature has done all the dissolution of silica under the ground.” Mike suggests that because geothermal energy is more niche than wind or solar which are supported by giant global industries, it tends to fly under the radar of the general public and policy makers. “Geothermal is much smaller because it’s much more geographically specific. While New Zealand is blessed to have that, geothermal doesn’t have the prominence in the industrial world as some of the other technologies have. So it’s not necessarily seen as such a fantastic solution for New Zealand. Geothermal sits in the background quietly doing its thing and not overly visible to the public at large who might otherwise be calling out for more geothermal power plants.”