"In Indonesia, we are expanding a geothermal power project that not only will provide additional electrical power, but also will help Indonesia avoid more than 400,000 tons per year of carbon dioxide emissions."

With the acquisition of Unocal, Chevron became the world's largest geothermal producer.

For more than 30 years, we have been a major geothermal energy producer in Indonesia. Unocal added three more of the world's major geothermal energy projects: Gunung Salak in Indonesia and Tiwi and Mak-Ban in the Philippines.

Geothermal energy is produced when groundwater descending from the earth's surface meets molten magma reservoirs, typically at depths of up to 9,800 feet (3,000 meters). The fluids can be recovered by drilling wells — much like traditional oil and natural gas operations. Surface facilities separate steam from any liquid water that is produced, and the steam is used to power turbines for generating electricity. Excess fluids are returned to the reservoir, thereby regenerating the steam source.