press release

Unocal completes sale of Geysers geothermal interest to Calpine

El Segundo, Calif., March 23, 1999 - Unocal Corporation today said its has completed the sale of its 75-percent interest in a geothermal steam venture at The Geysers in Northern California to Calpine Corporation for $101 million.

"We expect to reinvest the proceeds from this sale into our core oil and gas exploration and production activities around the world," said Roger C. Beach, Unocal chairman and chief executive officer.

"We have expanded our oil and gas exploration business in the key deepwater hydrocarbon provinces -- the Gulf of Mexico, South and Southeast Asia, Latin America and West Africa - that offer significant growth opportunities and higher potential returns," Beach said.

The company has already announced plans for fast-track development of promising deepwater oil and gas fields in the Kutei Basin offshore East Kalimantan, Indonesia, and has participated in a successful discovery on the deepwater Mirage prospect in the Gulf of Mexico. Unocal began natural gas sales from a new project in Bangladesh this month and expects to start commercial natural gas sales from the Yadana project in Myanmar later this year.

In 1998, Unocal's international operations replaced 114 percent of production in 1998 (excluding sales and price-related revisions), primarily through exploration drilling. Spirit Energy 76, the company's Lower 48 U.S. unit, replaced 108 percent of its production (excluding sales and price-related revisions), essentially as a result of a 64-percent exploration success rate on the Gulf of Mexico shelf during the year.

Unocal's interest at The Geysers contributed approximately $18 million in pre-tax earnings and $23 million in pre-tax operating cash flow to Unocal's 1998 results.

Unocal will continue to operate the geothermal steam venture at The Geysers on behalf of Calpine for a transition period of up to 90 days.

Unocal also operates geothermal resource ventures in the Philippines and Indonesia, supplying steam for nearly 1,100 megawatts of installed generating capacity. The company also operates three, 55-megawatt geothermal power plants in Indonesia.

Unocal is one of the world's largest independent oil and gas exploration and production companies, with resource development, power plant and pipeline projects in Asia, the U.S. Gulf of Mexico region and Latin America.

Forward-looking statements about future capital investment in this news release are based on assumptions concerning market, competitive, regulatory, and other considerations. Actual results could differ materially as a result of factors discussed in Unocal's 1998 Form 10-K report filed with the Securities and Exchange Commission.

Updated: March 1999