The product of the proposed research is nanostructured bulk thermoelectric materials that have higher efficiency than conventional materials so that high levels of power can be produced in an environmentally clean (pollution free) manner. The manufacturing technology developed during this program will not only be applicable to the proposed materials but to any thermoelectric material with suitable modifications. This will result in manufacturing of thermoelectric power generation and cooling devices with high efficiency and at economically viable cost. NASA anticipates the need for advanced power generation and conversion that goes well beyond the capabilities of the current level of technology for the success of its future missions. Systems are needed that provide significantly better conversion efficiency, higher specific power and enhanced operational capabilities. Thermo-electric power generation (TEPG) has exceptionally rich potential to contribute to electrical power generation in space based applications, and the potential of enabling large-scale electric power generation. The materials and devices that will result from this research will be useful for both power generation and cooling applications. Major commercial application is in the area of vehicle waste heat recovery (generally from the exhaust pipe) and is very attractive to auto makers in the country. Government agencies like DOD and DOE have a need for thermoelectric power generation for specialized applications. TEPG modules built from suitable thermoelectric materials can be used to build self-powered water and space heating systems, to retrieve the waste heat emitted from incinerators, power plants, or other similar sources, to promote the practice of green building, and even to generate power using human body heat. Development of TEPG materials will advance the state-of-the art in systems and components by reducing / replacing the use of fossil fuels in a cost effective manner.