Work Groups from Argentina, Paraguay and Uruguay integrated by renewable energy specialists and sociologists performed coordinately this technology transfer project funded by OAS, between 2001 and 2004. The project installed at public centers energy systems using solar thermal, PV and wind energies at six isolated communities as showcases of sustainable and easy to reproduce solutions to their energy needs. The communities were selected using the same basis. At each community, several meetings and an energy needs enquiry were performed. Finally, in a workshop, all the beneficiaries decided about the technology transfer. The systems, carefully designed in view of the available energy resources and their future operation and maintenance, were PV systems, windmills, basin type solar stills, solar water heaters, UV and filter PV water purifiers and water pumping systems. The experiences obtained in these communities with different cultures, located in diverse geographical zones were enriching and allowed to establish a methodology in the technological transference of renewable energy systems.