| Title | Steaming Ground Heat-Flux Assessment: Reducing Uncertainties |
|---|---|
| Authors | C.J. Bromley, S.M. van Manen, Warren Mannington |
| Year | 2011 |
| Conference | Stanford Geothermal Workshop |
| Keywords | heat-flux, Wairakei-Tauhara, steaming-ground |
| Abstract | Improved calibration of geothermal reservoir models can be achieved with more accurate input data, including assessments of surface heat loss from areas of naturally steam-heated ground. In the past, these have proven to be notoriously difficult to assess, with large uncertainties leading to poor knowledge of changes in surface heat flux values. Using a 2009-2010 comprehensive study of heat flux from the Tauhara sector of the Wairakei-Tauhara system as a case study, this paper discusses three new practical methods and a theoretical approach, which reduce the uncertainties in such assessments. This has implications for improved monitoring of heat flux values in similar settings, and therefore improved predictive capabilities of future reservoir simulations. The total heat loss from surface thermal features in 2010 at Tauhara was assessed to be 86 (+/- 10) MW (thermal), similar to the 1950’s pre-Wairakei assessment of heat loss from the same area of about 100 MW, and significantly less than the 1970’s assessment of about 220 MW. A higher proportion (63%) now originates from areas of steaming ground compared to discharging hot springs. |