NASA's Radioisotope Power Systems and Technologies - A Forward Look

For 50 years, the use of radioisotope power systems for spacecraft applications has continued to evolve and mature. Advances in energy conversion component technologies as well as in flight generators continue to this day. In 2008, an effort to consolidate management of these related efforts was initiated, and the formation of a NASA Radioisotope Power Systems Program began. NASA has now completed consolidation of its investments in Radioisotope Power Systems (RPS) through the approval of a single program office structure. The RPS Program’s goal is to make RPS available for the exploration of the solar system in environments where conventional solar or chemical power generation is impractical or impossible. While historical use of RPS dates back fifty years to the launch of a 2.7 watt generator, this program overview provides an integrated look into recent progress by the DOE-NASA team on the Advanced Stirling Radioisotope Generator (ASRG) system development and its preparation for potential mission applications on the current Discovery mission competition. The overview also explores technology maturation of thermoelectric and thermo-photovoltaic technology as well as systems development status and plans. Possible RPS-based missions and destinations that were discussed as part of the recently completed Planetary Science Decadal Survey are identified and placed in context of the program implementation. Opportunities for RPS generator development and targeted research into RPS component performance enhancements as well as constraints dealing with the supply of radioisotope heat sources are also discussed in the context of the next 10 years of Planetary Science mission plans.