AUSTRALASIA: GEOTHERMAL REPORT 2015

Transcription

1 AUSTRALASIA: GEOTHERMAL REPORT 2015 Juliet Newson Contact Energy Ltd. Geothermal Resources Council 39 th Annual Meeting September 20 th 23 rd 2015, Reno, NV

2 AUSTRALIA Ground source heat pump installation rapidly increasing Hot spring spa industry emerging in Victoria Increased direct use of thermal groundwater, especially in Perth. Completed: Ground Water Cooling project in Perth that involves the rejection of waste heat from a supercomputer into a shallow aquifer Lack of large scale development due to: unsupportive and risk-averse investment markets unexpected technical issues unstable policy settings. Birdsville Geothermal Power Plant continues to generate 80 kwe net from a 98 C artesian well in Central Australia. Beardsmore et al, Proceedings World Geothermal Congress 2015

3 NEW ZEALAND ELECTRICITY SCENE 80% renewable 16% geothermal

4 OUR GEOTHERMAL SYSTEMS Large scale convecting geothermal systems Liquid dominated Reservoirs at ~ boiling point for depth High rainfall, high permeability = high recharge & mass flow rates 220 C -320 C Reservoir temperature From Bernal et al, Geochimica et Cosmochimica Acta 126 (2014) p

5 NZ GEOTHERMAL GENERATION

6 KAWERAU +8 MWe NGAWHA +15 MWe KAWERAU +23 MWe KAWERAU +100 MWe NGA AWA PURUA +138 MWe NGATAMARIKI +82 MWe

7 Recent development summary BIO-REACTOR Condensate treatment TE HUKA +28 MWe TE MIHI +160 MWe DRILLING & STEAMFIELD

8 Recent drilling program 2013 Ohaaki 2006 Wairakei Why: -Make-up - New production - Reinjection -Exploration - Appraisal -Direct heat - Subsidence investigation From Winmill et al, Proceedings World Geothermal Congress 2015 Result: - Reinjection capacity: 3 * increase - 2 super-wide wells, casing 18-5/8 - Contact s deepest well (3020 m) - Hottest wells yet > 300 C

9 Steamfield development From Harwood et al, Proceedings World Geothermal Congress 2015 Challenges: Ultimately supply 3 stations with different pressure requirements Flexible swing of steam between 3 stations Dual redundant & dual modes of reinjection capacity Commissioning Te Mihi while maintaining baseload to other stations Optimize capacity of older plant to accommodate project deferrals Land scarcity with power station & well-pad requirements Scalability for a 3 rd Te Mihi turbine

10 Wairakei Bioreactor Achieves the required reduction in H 2 S discharges to the Waikato River from the Wairakei Power Stations Old Wairakei Power Station has direct contact condensers using river water Pipe field POWER STATIO N Old flow inlet outlet

11 Wairakei Bioreactor Total pipe length 378 km Water flow at 13 m 3 /s Water takes ~ four minutes to travel the 378 km of pipes Over three million litres of treated water being returned to the river PIPE FIELD every four minutes Largest industrial scale biofilm facility of its type in the world proven to reduce the amount of hydrogen sulphide in the cooling water from a geothermal power plant from POWER STATION

12 DIRECT USE From Carey et al, Proceedings World Geothermal Congress Tauhara 20 MW th timber drying Norske Skog Tasman Pulp & Paper mill use 2007 Mokai 11.7 hectares of glasshouses Increased use of geothermal heat in rebuilding from Christchurch 2010 & 2011 earthquakes 2010 Svenska Cellulosa Aktiebolaget Tissue mill Clean steam supply (Ngati Tuwharetoa Geothermal Assets) 2010 Mokai Miraka milk drying plant

13 PROFESSIONAL WORK (who did it?) Professional person-years of effort Data from Carey et al, Proceedings World Geothermal Congress 2015

14 FUTURE Geothermal is the most cost-effective electricity generation option, but electricity demand flat 3 new power plants consented (315 MW) Optimizing use of the consented fluid take Managing the reservoir in a sustainable manner Increased direct use of heat Researching & teaching geothermal

15 Photo of Wairakei by Dr Fabian Sepulveda, Contact Energy Ltd. Thank you