Methodology Applied for Thickness Selection and Stored Heat Evaluation in Non-producer Geothermal Wells in Order to Its Investment Rescue
Alfonso Aragon- Aguilar *
Instituto Nacional de Electricidad y Energías Limpias (INEEL), Reforma 113, Col. Palmira, Cuernavaca, Morelos, CP 62490, Mexico.
Georgina Izquierdo- Montalvo
Instituto Nacional de Electricidad y Energías Limpias (INEEL), Reforma 113, Col. Palmira, Cuernavaca, Morelos, CP 62490, Mexico.
Dominic A. Becerra- Serrato
Instituto Nacional de Electricidad y Energías Limpias (INEEL), Reforma 113, Col. Palmira, Cuernavaca, Morelos, CP 62490, Mexico.
Victor M. Monrroy- Mar
Tecnológico de Poza Rica, Luis Donaldo Colosio, S/N, Poza Rica, Ver., 93230, Mexico.
*Author to whom correspondence should be addressed.
Abstract
An assessment methodology of stored heat in rock formation surrounding to wellbore in geothermal systems is shown. Due to geothermal systems generally are nested in volcanic rock, it is characteristic its heterogeneous behavior. Proposed methodology starts since zone selection with possibilities of heat store. This methodology is focused to be applied in geothermal reservoirs with tendency to production decline, due to low permeability and unbalance between exploitation and water recharge. Because the high costs of drilling geothermal wells, methodology shown in this work is proposed to be applied in those with production decline or non-producers, in order to rescue its investment. The objective is to select the thickness with heat, evaluate its storage, design the appropriate instrumentation for its recovery, its energy conversion and rescue its investment done. The different designs for energy recovery using non-conventional methods to those, used habitually are reviewed. Each one of the variables for stored heat calculation was determined using technical tools of reservoir engineering. A parametric analysis about variables sensitivity (porosity and drainage radius) for determining thermal energy and corresponding electric energy of analyzed rock volume is done. Practical application of this methodology was carried out using data of one of wells of Los Humeros Mexican geothermal field.
Keywords: Los Humeros Geothermal Field (LHGF), low permeability, thickness evaluation, heat storage, high temperature, thermal energy, electricity generation.