Assessment of high enthalpy geothermal resources and promising areas of Chile

Abstract

Artículo de publicación ISIThis work aims to assess geothermal power potential in identified high enthalpy geothermal areas in the Chilean Andes, based on reservoir temperature and volume. In addition, we present a set of highly favorable geothermal areas, but without enough data in order to quantify the resource. Information regarding geothermal systems was gathered and ranked to assess Indicated or Inferred resources, depending on the degree of confidence that a resource may exist as indicated by the geoscientific information available to review. Resources were estimated through the USGS Heat in Place method. A Monte Carlo approach is used to quantify variability in boundary conditions. Estimates of total Indicated resource are confined to 3 geothermal systems; Apacheta, El Tatio and Tolhuaca, yielding a total value of 228 +/- 154 MWe. The estimates of the total Inferred resources for Chile include 6 geothermal systems and yield a total value of 431 +/- 321 MWe. Standard deviation reflects the high variability of reservoir specific parameters for each system. A set of 65 favorable geothermal areas are proposed as the most likely future development targets. Eight of them have initial exploration results that suggest they are highly favorable targets as potential geothermal resources.FONDAP/CONICYT (Centro de Excelencia en Geotermia de los Andes, CEGA) 15090013 Departamento de Geologia, FCFM, Universidad de Chile Lawrence Berkeley National Laboratory under U.S. Department of Energy U.S. Department of Energy DE-AC02-05CH1123

Opportunities and Challenges for Scaling Up Geothermal Development in Latin America and the Caribbean

“…In fact, geothermal energy now accounts for approximately 7.5 percent of Central America's total electricity generation, 11 with several studies indicating that there is an opportunity for the percentage to be vastly increased. 12 The estimated geothermal potential in the Mexico and Central America sub-region is likely to range between 5,600 MW and 6,900 MW, 13 of which less than 30 percent has been exploited thus far for power production.…”

“…14 Historically, the electricity sector in the country has been managed and developed by 11 Dolezal et al 2013; ESMAP 2013b. 12 ESMAP 2012. 13 Based on geothermal expert review of estimates of geothermal resource potential for electricity generation in these countries generated by different authors, and judgement of "most likely value."…”

Geothermal potential assessment of the Nevado del Ruiz volcano based on rock thermal conductivity measurements and numerical modeling of heat transfer

“…Recent studies on the estimation of the geothermal potential have been conducted in few countries of South America, where there are no operating geothermal power plants. Aravena et al (2016) estimated the geothermal potential of high enthalpy geothermal areas of Chile to 659 MWe, applying numerical methods and including inferred resources. Invernizzi et al (2014) described a preliminary assessment of the geothermal potential of Rosario de la Frontera area to the northwest of Argentina, indicating 5.6x10 18 J of heat stored in the rock and 0.8x10 18 J in the geothermal fluids.…”

“…The minimum and maximum values were 1.28 × 10 -2 MW t m -1 and 2.59 × 10 -2 MW t m -1 , respectively (Figure 8). Considering the same reservoir width of 5 km, the mean estimated geothermal potential was now 94 MW t , while the minimum and maximum values were 64 MW t and Numerical modeling based on the finite element method is recommended for the estimation of geothermal potential (Aravena et al, 2016), since it provides a rigorous way to evaluate and understand conceptual models and the system heat transfer mechanisms. Similarly, González-Garcia and Jessell (2016) stated that numerical modeling of heat and mass transfer in a hydrothermal system is a proper tool to provide a quantitative estimate of geothermal resources, as well as to aid in the sustainable management of these resources.…”

The layered model of the Copahue geothermal reservoir, Argentina

“…1a). The most relevant are El Tatio and Cerro Pabellon in Chile (Aravena et al 2016;Vargas and Püschel-Lovengreen 2016), Laguna Colorada in Bolivia (Terceros 2000;Villarroel Camacho 2014), and currently Chachimbiro in Ecuador. The Cordón Caulle geothermal system in Chile is an excellent example of the inherent complexity of establishing a conceptual model in this setting.…”