Micro nuclear reactors

I've already talked  about the small nuclear reactors NASA has developed for use in space and on Mars, called KRUSTY.  These will produce 1 kW of power, with the scaled-up version producing 10 kW.   I've also mentioned small modular reactors, here.

Ex-SpaceX engineers are developing a micro, portable nuclear reactor that can produce 1 MW of electricity, 100 times more than the scaled up version of NASA's KRUSTY nuclear reactor, designed to portable on the back of a lorry and with safety features allegedly making it much safer than the behemoths that catastrophically melted down at Chernobyl and Fukushima.  Since the company is still in the process of acquiring patents, there aren't many details.  

For me, one of the interesting aspects of this development is that SpaceX seems to have a division designing small nuclear reactors for use on Mars.  And on Starship?  No wonder SpaceX's latest video update about Starship shows it journeying to Mars without deploying solar panels!  

Using helium as a coolant certainly reduces the risk of explosions.  No mention of how nuclear waste is to be disposed of, though.

It's intriguing to see lots of private sector companies producing new designs for nuclear fission reactors.  The old super large designs seem to have got stuck in an expensive cul-de-sac.  Nuclear reactors will be very useful right here on Earth, if they can be made cheap enough and safe enough, as a complement to renewables in our electricity grids.  Lots of competing designs and companies might get us there quicker than large government bureaucracies, with both nuclear fission and fusion.

From New Atlas

California company Radiant has secured funding to develop a compact, portable, "low-cost" one-megawatt nuclear micro-reactor that fits in a shipping container, powers about 1,000 homes and uses a helium coolant instead of water.

Founded by ex-SpaceX engineers, who decided the Mars colony power sources they were researching would make a bigger impact closer to home, Radiant has pulled in US$1.2 million from angel investors to continue work on its reactors, which are specifically designed to be highly portable, quick to deploy and effective wherever they're deployed; remote communities and disaster areas are early targets.

The military is another key market here; a few of these could power an entire military base in a remote area for four to eight years before expending its "advanced particle fuel," eliminating not just the emissions of the current diesel generators, but also the need to constantly bring in trucks full of fuel for this purpose.

Those trucks will still have to run – up until the point where the military ditches diesel in all its vehicles – but they'll be much less frequent, reducing a significant risk for transport personnel.

Radiant says its fuel "does not melt down, and withstands higher temperatures when compared to traditional nuclear fuels." Using helium as the coolant "greatly reduces corrosion, boiling and contamination risks," and the company says it's received provisional patents for ideas it's developed around refueling the reactors and efficiently transporting heat out of the reactor core.

Radiant joins a number of companies now working on compact nuclear reactors, and a smaller number focusing specifically on portable units, which would include the floating barges proposed for mass-manufacture by Seaborg. It'll be a while before we see one up and running, but a clean, convenient, low-cost, long-life alternative to diesel generators would be very welcome.