The immediate NASA application is for space fission nuclear reactors that utilize Stirling converters or thermoelectric for power conversion. Specifically, the 1kWe Fission Power System with a 15 year design life. The alkali metal heat pipes developed in this program would be capable of transporting the reactor heat to the Stirling or thermoelectric convertors for power generation. The Stirling system and other space nuclear reactors also require radiator panels to reject waste heat. The grooved and self-venting arterial heat pipes developed on this program will also be suitable to the lower temperature radiator heat pipes. The high temperature heat pipes developed under this program can also be used for waste heat energy recovery and utilization, specifically for automotive engines and military generator sets. The exhaust heat generated in these applications is considered high-grade heat and would require alkali metal heat pipes for collection and transportation. The high temperature heat pipes developed under this program could be used to collect the high-grade exhaust heat and transfer it to either a catalyst convertor to reduce the energy needed for vehicle startup or to Stirling engines for electrical energy generation. A second application is high temperature solar receivers. These devices are currently being investigated to provide the necessary thermal power to aid in alternate energy generation. The thermochemical reduction processes used to generate alternate energy must be performed at very high temperatures. The high temperature heat pipes developed in this program could be used to transfer the thermal energy collected by a solar receiver to a reactor to aid in the thermochemical reduction process.