Geothermal turning up the heat at the Los Humeros geothermal field, Puebla, Mexico

Abstract

Geothermal power is a highly reliable source of base load, renewable power. This is a feature that utilities, looking to increase their share of renewables in the energy mix while maintaining secure supply, will no doubt find attractive. Despite the relatively high installation costs for a direct-cycle geothermal power plant, the high capacity factor in operation results in a competitive levelized cost of electricity, even when taking into account the cost of drilling the wells and building the steam collection system. In May and December 2009, CFE awarded Alstom contracts to build two 25-MW power plants in the Los Humeros geothermal field, located in the state of Puebla, Mexico, 225 km southeast of Mexico City. When they begin operation, the two plants --known as Los Humeros II, Units 9 and 10-- will produce more than 400 GWh annually of reliable, clean electricity, enough to power 100,000 homes in the Puebla state. This paper presents the main features of the Units 9 and 10, currently under construction.