Analysis of power cycles for geothermal wellhead conversion systems. Final report

The purpose was to develop a data base and preliminary guidelines for selecting the energy conversion systems and working fluids that would efficiently utilize geothermal resources in the 200 to 600/sup 0/F temperature range. A large number of working fluids were screened and detailed thermodynamic analyses were performed for 240 combinations of brine temperatures condensing temperatures, working fluids, and energy conversion systems including single- and dual-pressure binary systems, single- and double-flash systems and total-flow systems comprising a rotary separator turbine and a condensing steam turbine. Summary thermodynamic and performance data were tabulated for each of the 240 cases, from which the upper envelope of achievable resource utilization efficiency was established. Preliminary guidelines for system and fluid selection were also developed. 16 refs., 23 figs., 14 tabs.