Geothermal Resources

​​​​​​​​​​​​​​​​​Geothermal Energy Pie Chart

Geothermal energy comes from heat stored in rocks and fluid in the Earth’s crust. Geothermal fluids may be steam or hot water. With more than 650 active, high-temperature (fluids over 212 degrees F) wells that tap into geothermal fields, California is the largest generator of electricity from geothermal energy in the United States. In 2018, the state received 5.92 percent of its electrical energy from geothermal resources.

The Geologic Energy Management Division (CalGEM) supports development of this clean, renewable energy resource while prioritizing the health and safety of the public and the environment. CalGEM regulates​ the operation, maintenance, and permanent closure of production and injection wells used for the discovery and extraction of geothermal resources on state and private land. Geothermal energy is part of the answer as California aims toward carbon-neutrality by 2045.


The CalGEM Geothermal and GIS Mapping units have published  ​​new, dynamic statewide maps that display spatial and other information about geothermal well resources and data in California. The maps are updated nightly.

Active Rulemaking

Discussion Draft.  The CalGEM geothermal unit and Department of Conservation legal and regulatory staff have reviewed and assessed public feedback on the discussion draft. They are developing documentation for a formal regulations draft.

Current Geothermal Statutes and Regulations​​

Additional Information

Frequently Asked Questions (FAQs)

GIS Mapping

Geothermal Data

Geothermal Technical Reports

For Operators

CalGEM conducted two workshops for geothermal operators. One session focused on geothermal project compliance with the California Environmental Quality Act (CEQA) and CalGEM's role in CEQA. Compliance documentation, indemnity agreements, project descriptions, and acceptable CEQA submittals and examples were discussed.

A second session covered blowout prevention equipment (BOPE) requirements for high temperature hydrothermal geothermal resources and DOGGR (now CalGEM) Publication Instruction Manual No. M07, PT2, Section 4.

Geothermal Requirements, Records, and Related Information

Geothermal Forms

GeoSteam well search and data

​ ​