posted on Jun, 14 2003 @ 06:40 PM
Radioisotope Thermal Generators (RTGs) are essentially a thermocouple attached to an atomic material, (generally low grade, equivalent to the energy
released by a microwave over or less) that slowly decays, releasing a controlled amount of heat. The thermocouple converts the heat directly into
By contrast, a true nuclear reactor uses a number of highly energetic subcritical masses to react to each other in a classic fission reaction. The
heat generated is generally converted into electricity by means of a steam turbine (thermocouples are not efficient for large amounts of heat energy).
Stirling RTG link
The Stirling engine is a candidate for use with isotope power systems. In the references below, Bents et al. (1992, 1992, and 1991) discuss the
application of free-piston Stirling convertors to dynamic isotope power systems (DIPS). DIPS could have applications to a variety of unmanned deep
space and planetary exploration missions. The RTG (radioisotope thermoelectric generator) is the power source currently available for these mission
requirements. The Stirling convertor is able to achieve higher efficiencies at these lower power levels, thus, allowing a significant reduction in the
amount of isotope required. Thermal photovoltaic power systems are beginning to sound like a very attractive possibility for isotope power, but are
still in an early stage of development.