Phase 0 of a project for Experimental Geothermal Research Facilities focuses on identification of a representative liquid-dominated geothermal reservoir of moderate temperature and salinity, preliminary engineering design of an appropriate energy conversion system, identification of critical technology, and planning for implementation of experimental facilities. The objectives included development of liaison with the industrial sector, to ensure responsiveness to their views in facility requirements and planning, and incorporation of environmental and socioeconomic factors. The overall project, of which the six-month Phase 0 is reported herein, is phased in accordance with RANN guidelines. This Phase 0 report covers problem definition and systems requirements. Phase 1 will involve design of the experimental facility, and testing of components. Phase 2 will comprise detailed design and construction of an experimental geothermal electrical powerplant at East Mesa, Imperial County, California. Facilities will incorporate capability for research in component, system, and materials technology and a nominal 10 MWe experimental, binary cycle, power generating plant.