Yeah I don’t know how else to use nuclear radiation to make power except by heating water into steam. I know nasa has played with tiny reactors for spacecraft, but I don’t know how they work. Perhaps they have something like a solar panel sitting next to a uranium rod and it generates electricity from that instead of photons?
They take advantage of the Seebeck effect which is where a voltage is generated between two points in a conducting material when there’s a temperature difference between them. Basically the nuclear material heats one piece of metal in the circuit, while another remains cold, and this produces a potential difference between the two that drives current through the circuit. Because space is very cold and nuclear materials are very hot, this produces a useful quantity of current. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
yes, while space is cold, the vacuum means that nearly all the heat has to be shed by radiation (meaning e.g. infrared radiation, not nookyular radiation) rather than conduction & convection. so the more you scale it up, the bigger the heat sinks needed. think giant metal fins to radiate away the heat. eventually it becomes prohibitive.
interestingly, the 40KW NASA pilot project this proposal appears to be derived from is a Stirling engine, not a radioisotope thermal generator like on New Horizons, Cassini, etc.
a Stirling design converts much more of the heat to electricity than an RTG, but it has moving parts.
Yeah I don’t know how else to use nuclear radiation to make power except by heating water into steam. I know nasa has played with tiny reactors for spacecraft, but I don’t know how they work. Perhaps they have something like a solar panel sitting next to a uranium rod and it generates electricity from that instead of photons?
They take advantage of the Seebeck effect which is where a voltage is generated between two points in a conducting material when there’s a temperature difference between them. Basically the nuclear material heats one piece of metal in the circuit, while another remains cold, and this produces a potential difference between the two that drives current through the circuit. Because space is very cold and nuclear materials are very hot, this produces a useful quantity of current. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator
So they’re going to have to scale this method way the fuck up to get to 100kw.
yeah it’d be very unfeasible
yes, while space is cold, the vacuum means that nearly all the heat has to be shed by radiation (meaning e.g. infrared radiation, not nookyular radiation) rather than conduction & convection. so the more you scale it up, the bigger the heat sinks needed. think giant metal fins to radiate away the heat. eventually it becomes prohibitive.
interestingly, the 40KW NASA pilot project this proposal appears to be derived from is a Stirling engine, not a radioisotope thermal generator like on New Horizons, Cassini, etc.
a Stirling design converts much more of the heat to electricity than an RTG, but it has moving parts.