Direct Use A Reality Check

摘要

Direct use, or non-electric applications of geothermal energy, has enjoyed modest growth over the past 20 years. Despite the considerable geographic distribution of direct use (18 states have projects online) and the number of individual systems in operation (approximately 1,338 as of 2003), there remains in the geothermal industry an incomplete understanding of direct use and its potential. There is frequently the perception that industry is clamoring for access to geothermal resources, that district heating is widely applicable, and if we build it geothermally, "They will come." In fact, opportunities for new direct-use development and the circumstances under which it is economically feasible are quite narrowly defined. Exploring the concentration of past project development, the current status of direct use, and likely future trends will assist in identifying necessary strategies to sustain the technology in the future.