Geothermal resource evaluation was accomplished for the Baja California Peninsula hydrothermal systems. Numerous geothermal areas were identified along the eastern coast of the Peninsula, which are related with the Gulf of California opening process. The western coast presents hydrothermal activity in the northern part related with regional faults like the Agua Blanca Fault nearby Ensenada. The southern part of the Peninsula also has abundant geothermal resources related with local grabens. The heat in place evaluation was accomplished for five geothermal areas where geophysical data were available to estimate the reservoir volume. The minimum calculated potential is more than 400 MWe. There are still more than six geothermal prospects with calculated temperatures above 200 degrees C that lack reliable information on the reservoir volume and would increase the geothermal potential of the Peninsula. Surface heat loss from the submarine systems reaches more than 6000 MWt. (C) 2015 The Authors. Published by Elsevier Ltd.