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Yes and no. The Kilopower design is not an RTG (Radioisotope Thermoelectric Generator). Those rely on the decay of a heavy element like plutonium to generate h

Yes and no. The Kilopower design is not an RTG (Radioisotope Thermoelectric Generator). Those rely on the decay of a heavy element like plutonium to generate heat, which then generates electric power using a thermocouple. Kilopower is making an actual fission reactor, which generates heat from the chain reaction of fissile atoms splitting each other. Another difference is that their design will utilize a linear-actuating sterling engine to convert the heat to electricity. That being said, you're correct. The management of thermal flux and particularly discharging waste heat is hugely important to keeping this design working and efficient.

rtkwe 7y ago
It's not 100% clear these are that different from RTGs it sounds like they just use Stirling engines instead of thermocouples to do the heat -> electricity conversion which is more efficient than the old style but seem largely the same otherwise.
- spinningleaves 7y ago
  Again, this reactor design is different from an RTG, precisely because it is a reactor. RTGs like those used in the Cassini mission rely on radioactive decay to generate heat. They have a significantly smaller power output, on the scale of watts. In Cassini's case, PuO2 fuel was used, and the primary decay mode was alpha decay. These designs are great for long-term, low power missions. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge... Kilopower will utilize highly-enriched uranium fuel to power a fission reactor. This means that the atoms in the fuel will be sustaining a chain reaction of fissioning, releasing neutrons, causing more atoms to fission, and on and on. This is what generates heat in reactor systems. This design will prove usable for shorter, higher energy demand missions. https://www.nasa.gov/directorates/spacetech/kilopower https://www.nasa.gov/directorates/spacetech/kilopower An RTG is essentially a lump of fuel which sits and decays, generating heat. Kilopower's reactor would be an actual reactor, needing to manage reactivity, burnup, and maintain criticality. They are vastly different systems. For someone not in the field I can see how there'd be some confusion but please be less speculative on topics of which you're less familiar.

rtkwe 7y ago

It's not 100% clear these are that different from RTGs it sounds like they just use Stirling engines instead of thermocouples to do the heat -> electricity conversion which is more efficient than the old style but seem largely the same otherwise.

spinningleaves 7y ago
Again, this reactor design is different from an RTG, precisely because it is a reactor. RTGs like those used in the Cassini mission rely on radioactive decay to generate heat. They have a significantly smaller power output, on the scale of watts. In Cassini's case, PuO2 fuel was used, and the primary decay mode was alpha decay. These designs are great for long-term, low power missions. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge... Kilopower will utilize highly-enriched uranium fuel to power a fission reactor. This means that the atoms in the fuel will be sustaining a chain reaction of fissioning, releasing neutrons, causing more atoms to fission, and on and on. This is what generates heat in reactor systems. This design will prove usable for shorter, higher energy demand missions. https://www.nasa.gov/directorates/spacetech/kilopower https://www.nasa.gov/directorates/spacetech/kilopower An RTG is essentially a lump of fuel which sits and decays, generating heat. Kilopower's reactor would be an actual reactor, needing to manage reactivity, burnup, and maintain criticality. They are vastly different systems. For someone not in the field I can see how there'd be some confusion but please be less speculative on topics of which you're less familiar.