The Pima County Area Development evaluated the county-wide market potential for utilizing geothermal energy. The study identified four potential geothermal resource areas with temperatures less than 100{sup 0}C (212{sup 0}F), and in addition, one area is identified as having a temperature of 147{sup 0}F (297{sup 0}F). Geothermal resources are found to occur in Tucson where average population growth rates of two to three percent per year are expected over the next 40 years. Rapid growth in the manufacturing sector and the existence of major copper mines provide opportunities for the direct utilization of geothermal energy. However, available water supplies are identified as a major constraint to projected growth. The study also includes a regional energy analysis, future predictions for energy consumption and energy prices. A major section of the report is aimed at identifying potential geothermal users in Pima County and providing projections of maximum economic geothermal utilization. The study identifies 115 firms in 32 industrial classes that have some potential for geothermal use. In addition, 26 agribusiness firms were found in the county.