Developments in geothermal energy in Mexico—part eight: Geothermal reservoir energy recovery: A 3-D numerical simulation study of the Cerro Prieto geothermal field

Cerro Prieto is the most developed Mexican geothermal field. Currently, two power plants produce electricity from it. The oldest, CP I, as been on line for more than a decade; CP II recently started producing at half capacity, and CP III is scheduled to come on line soon. In this work we investigate the mass and heat reserves, the corresponding deliverability, and the expected quality of the heat delivered, in relation to CP I. We also inquire into the likely effect of the planned production of the CP II and CP III power plants on the future performance of CP I. The investigation is accomplished via numerical simulation. Our results indicate that the reserves of mass and heat in the layers that feed CP I are adequate for a thirty year economic life of the plant, that the quality of the produced heat will decline with time to about 85% of its peak value, and that the main effect of production by CP II and CP III is to enhance recharge by cool water of the zone that feeds CP I.