| Title | Numerical modelling and resource assessment of the NRV geothermal field, Colombia |
|---|---|
| Authors | A.J.P. Mendez, J. OSullivan, K. Dekkers |
| Year | 2024 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | Nevado del Ruiz Volcano (NRV), geothermal modelling, resource assessment, uncertainty |
| Abstract | The Nevado del Ruiz Volcano (NRV), located in the central cordillera of Colombia, is one of the most monitored volcanoes in the world due to its destructive capability. Thanks to this, there is abundant information regarding its surrounding structures and the behaviour of the edifice itself. This information has been used over the years to study the potential of the area to produce geothermal energy; however, because of the political and economic circumstances of the country, geothermal development has been slow and disorganised, and exploration projects have focused on understanding its geology and the geochemistry of the surface features associated with it, but the underground structures have not yet been extensively studied. This research aimed to gather the open-source information of the field and compile it to create a geological model of the area using Leapfrog Energy 2023.1. Furthermore, this geological model was used to create a discretised numerical reservoir model, using AUTOUGH2, that matched the estimated subsurface structures and the surface manifestations found in the zone. The calibrated numerical model of the NRV obtained matched the expected flow patterns of the field, which were estimated based on two groups of surface manifestations: group one (G1), of acidic nature, located to the west of the volcano and believed to correspond to the upflow of the field, and group two (G2), located further away from the volcano in its north-western flank, which presented alkali-chloride mixed waters and is believed to be the outflow region. Additionally, this numerical model was used to perform a resource assessment and predict, considering uncertainty, how much power the field could produce based on a resource assessment method developed by Dekkers et al. at the University of Auckland. Using this method, the estimated NRV mean power production potential was above 150MWe over an exploitation period of 25 years, with a confidence interval P90 of about 100MWe and P10 of about 200MWe. |