Geothermal Leasing Research Articles

Developments in Geothermal Resources in 1982

The total number of geothermal wells drilled in 1982 decreased to 79 from 99 wells in 1981. Total footage drilled in 1982 decreased to 559,326 ft from 676,127 ft in 1981. An increase in average well depth from 6,830 ft in 1981 to 7,080 ft in 1982 indicated that operators are having to drill deeper in their efforts to extend the productive limits of proven geothermal reservoirs. Of the 79 geothermal wells completed in 1982, about 80% (i.e., 63 wells, which accounted for 90% of the total footage) were drilled in California. Two major acquisitions occurred during 1982 in The Geysers geothermal field in northern California. Geothermal Resources International, Inc. (GRI), purchased Thermogenics, Inc. (TGI), including the steam-producing property from which TGI sells steam to the Pacific Gas and Electric Co. (PG&E) Unit 15 geothermal power plant. Additionally, GRI purchased the 50% interest of Aminoil USA, Inc., in about 60,000 acres within and around The Geysers for $26.25 million in the largest transaction negotiated in the geothermal industry during 1982. GRI then entered into agreements for the exploration and development of the acreage with the Central California Power Agency. Geothermal power generation was highlighted at The Geysers by an increase of 110 MWe of electricity. With the start-up of PG&E Unit 17, the total capacity of The Geysers at year end was 1,019 MWe. In the Salton Sea KGRA in the Imperial Valley in southern California, the Southern California Edison Co. 10 MWe single flash demonstration plant became operational in 1982, bringing the total geothermal electricity generation capacity in the Imperial Valley to about 31 MWe. By mid-year, 5 development wells were completed by California Energy Co., Inc., at the Coso Hot Springs KGRA on the China Lake Naval Weapons Center in south-central California. These wells confirmed the dry steam discovery of late 1981 and established the Coso area as another important geothermal resource for electric l power generation. Other achievements included the accelerated federal geothermal leasing program reaching its goal of offering about 600,000 acres in 14 sales held by the U.S. Bureau of Land Management. Five other geothermal lease sales were conducted by 3 state agencies. Private industry paid more than $18.7 million in bonus bids in 1982 for geothermal leases at these competitive federal and state lease sales, an average of $113.20/acre. In 1982, 2 significant technical developments, the Crystallizer Clarifier Processor and the EFP System, were successfully demonstrated and will accelerate the commercial utilization of liquid-dominated geothermal resources in the United States and elsewhere. Finally, the dedication of several district heating projects highlighted the direct-use application of geotherm l resources in 1982.

Developments in Geothermal Resources in 1981

Several significant developments in the geothermal industry may change the course of geothermal development. The U. S. Department of Energy budget for fiscal year 1981-82 was reduced drastically. Natomas Co. acquired Magma Power Co., thereby changing participants in the development of The Geysers and providing acknowledgment by financial institutions of the value of geothermal reserves. California Energy Co., Inc., with its dry steam discovery well, established commercial production at the Coso Hot Springs KGRA in late 1981. There was dramatic acceleration in releasing federal lands for geothermal leasing. Finally, Occidental Geothermal, Inc., announced that it will build and operate an 80 MWe power plant near Anderson Springs, California, selling the electricity to Pacif c Gas and Electric Co. under the Public Utilities Regulatory Act (PURPA). Drilling of geothermal exploration and development wells showed a slight increase over 1980. In 1981, 99 wells accounted for 674,781 ft of hole. A total of 203,673 ft of hole was cut during the drilling of 37 geothermal exploratory wells. California again had the largest number of wildcats at 16, followed by Nevada with 10. Eight successful wildcats accounted for 34,862 ft of hole, with an average total depth of 4,358 ft. These include wells capable of producing dry and wet steam, as well as ones intended for direct-use applications. The wildcat success rate was 21.62%, down from the 1980 success rate of 47.37%. Of the 62 geothermal development wells in 1981, representing 471,108 ft of hole, 56 were considered capable of production. The development success rate of 90.32% is slightly b low the 1980 success rate of 94.83%. Also, there has been a significant increase in average depth, from 5,997 ft in 1980 to 7,901 ft in 1981. This seems to indicate that operators are having to drill deeper in their efforts to extend productive limits of proven geothermal reservoirs. Although there have been no new geothermal electrical power plants brought on-line in The Geysers during 1981, construction continued on 6 plants, with a combined capacity of 537 MWe, scheduled to become operational during 1982 through 1984. A strong trend is emerging in the area of power generation from geothermal resources: the development of small power plants (i.e., those of 1.5 to 20 MWe capacity). Two small facilities, 1 of 3 MWe at the Puna District in Hawaii and 1 of 1.6 MWe at the Roosevelt Hot Springs KGRA in Utah, became operational in 1981. This movement toward smaller, semiportable, less expensive power plants is healthy, and is indicative of the desire of utilities and geothermal operators to solve their mutual problems. With the approval for 2 new electrical transmissio lines, a major impediment to the eventual development of geothermal resources in The Geysers and the Imperial Valley has been removed. The construction of district heating projects highlights direct-use applications of geothermal energy in 1981.

Inventory of geothermal leasing and drilling activity in New Mexico

Inventory of geothermal leasing and drilling activity in New Mexico

Developments in Four Corners-Intermountain Area in 1976

Total drilling in the Four Corners-Intermountain area during 1976 decreased from that of 1975. The decrease was mostly in development drilling with a lesser decrease in exploratory drilling. On an individual basis, Arizona and Nevada recorded increases in exploratory drilling and the second oil field was discovered in Nevada. Success rates of 14% and 85.2% for exploratory and development wells were less than in 1975. Leasing activity was heavy in the east-central part of Nevada and extended into western Utah. Geothermal leasing and exploration were active in Utah and New Mexico. It is anticipated that both exploratory and development activity will increase in 1977.