Application of a Lumped Parameter Model to the Cerro Prieto Geothermal Field

Abstract

In this paper, a lumped parameter mathematical model for hot water geothermal reservoirs is developed and applied to the Cerro Prieto geothermal field in Mexico. The production and pressure histories of Cerro Prieto were assembled from field data. A computer program was then used to perform sensitivity studies on reservoir size, porosity, aquifer recharge, and temperature of recharge fluid. Two types of depletion schemes were investigated; in the first, the reservoir remains essentially one-phase liquid, and in the second, the reservoir becomes two-phase at a point early in its history. A satisfactory match of the history of the field has been obtained. This paper shows the usefulness of a lumped parameter model in clarifying the basic behavior of a hot water geothermal system and in giving focus to more complex two- and three dimensional modeling efforts. The results obtained specifically for the Cerro Prieto field will also be of value to the scientists and engineers studying this reservoir.