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NASA to test prototype Kilopower nuclear reactor

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Re: NASA to test prototype Kilopower nuclear reactor

#91

Post by willismichael »

Manglano wrote: post #85
pault wrote: post #81

Earlier quoted context omitted.

When I lived in Seattle I was sitting at a cafe one day and a government motorcade came down the street with an 18 wheel truck carrying a dumbell-shaped canister with a giant yellow nuclear symbol on the side. I've never been able to figure out what they were transporting. Does anybody here know what it might have been? It was post 9/11 so I was surprised they were still moving radioactive material on the surface str…

To some extent we are radioactive material on the surface streets of the major cities, because we have consumed soil!! Even our steel tools can be somewhat radioactive, refinement concentrates point sources. However, containment vessels like that are usually for refined ores, which end up in reactors, smoke detectors, medical devices, radiotherapy machines, you name it. Too expensive and possibly hazardous to airlift…

Waste from the Hanford Site? Why would it be necessary to transport it through the most populous area of WA state? (I'm asking as somebody who has lived near Hanford as well as in the Seattle metro area)

Re: NASA to test prototype Kilopower nuclear reactor

#92

Post by ChuckMcM »

hutzlibu wrote: post #75
dgoodell wrote: post #61

Earlier quoted context omitted.

One of the primary uses are deep space probes. The stirling engine has exactly two moving parts and uses non contact seals. In theory the lifetime should be limited by the deformation of the piston at elevated temperatures. Still, you’re right. They certainly have to do a lot of reliability testing to be able to show that these stirling engines will last 10+ years before they use them in a mission. They have several…

But on deep space missions, aren't you aiming for 50+ years, or ideally potentially unlimited if you want to hit alpha centauri? Voyager 1 is going for 50 years ...

Your point about moving parts is good, it is absolutely the place to look for possible failure. That said, it is also possible to build such things in a durable way. For example, at the science museum in London there was a display with a Stirling engine that over 75 years old and still works fine. I expect the challenge will be to keep the materials within the range of temperatures and pressures that do not cause structural change in the material.

Re: NASA to test prototype Kilopower nuclear reactor

#93

Post by RosanaAnaDana »

willismichael wrote: post #91
Manglano wrote: post #85

Earlier quoted context omitted.

To some extent we are radioactive material on the surface streets of the major cities, because we have consumed soil!! Even our steel tools can be somewhat radioactive, refinement concentrates point sources. However, containment vessels like that are usually for refined ores, which end up in reactors, smoke detectors, medical devices, radiotherapy machines, you name it. Too expensive and possibly hazardous to airlift…

Waste from the Hanford Site? Why would it be necessary to transport it through the most populous area of WA state? (I'm asking as somebody who has lived near Hanford as well as in the Seattle metro area)

Waste from Hanford would either stay at Hanford or go through Portland. Seattle is way out of the way. Portland much closer.

Re: NASA to test prototype Kilopower nuclear reactor

#94

Post by rijoja »

gambiting wrote: post #79
rijoja wrote: post #70

Earlier quoted context omitted.

But it would be perfect for a well isolated home wouldn't it?

Hmmmm a normal boiler for a 4-person family home is about 8-10kW so again, probably not. At least not for heating. But for normal power consumption should be ok, especially if paired with some storage device to account of periods of higher consumption(running a 3kW kettle for couple minutes for example).

Well yeah not the average household obviously but if you really wanted to get rid of your dependency on the grid it would be somewhat possible. As opposed to say drive a at least 70 HP ~ 50 KW car. Not a proposal for everybody of course but for lets say political idealists.

As far as the 3kW kettle is concerned having a battery to provide for these surges is entirely viable.

Re: NASA to test prototype Kilopower nuclear reactor

#95

Post by seanmcdirmid »

willismichael wrote: post #91
Manglano wrote: post #85

Earlier quoted context omitted.

To some extent we are radioactive material on the surface streets of the major cities, because we have consumed soil!! Even our steel tools can be somewhat radioactive, refinement concentrates point sources. However, containment vessels like that are usually for refined ores, which end up in reactors, smoke detectors, medical devices, radiotherapy machines, you name it. Too expensive and possibly hazardous to airlift…

Waste from the Hanford Site? Why would it be necessary to transport it through the most populous area of WA state? (I'm asking as somebody who has lived near Hanford as well as in the Seattle metro area)

Eh, it also doesn’t make sense since Hanford is a waste storage site...where else could the waste be going, and even if it’s high grade, why does that involve the Pacific Ocean rather than a trip to Utah or neveda in the other direction? I’ll assume that whatever it was, it was unrelated to Hanford, more likely something to do with nuclear submarines or the training reactor they had at UW.

Re: NASA to test prototype Kilopower nuclear reactor

#97

Post by scrumbledober »

ChuckMcM wrote: post #92
hutzlibu wrote: post #75

Earlier quoted context omitted.

But on deep space missions, aren't you aiming for 50+ years, or ideally potentially unlimited if you want to hit alpha centauri? Voyager 1 is going for 50 years ...

Your point about moving parts is good, it is absolutely the place to look for possible failure. That said, it is also possible to build such things in a durable way. For example, at the science museum in London there was a display with a Stirling engine that over 75 years old and still works fine. I expect the challenge will be to keep the materials within the range of temperatures and pressures that do not cause str…

Has that stirling engine had zero maintnence in the last 75 years? If so that is quite impressive and gives much more confidence that NASA can pull this off with the benefit of three quarters of a centruty of technological advancement.

Re: NASA to test prototype Kilopower nuclear reactor

#98

Post by bildung »

Filligree wrote: post #67
bildung wrote: post #32

Earlier quoted context omitted.

The half-life of the currently used fuel (Plutonium 238) is 87 years.

The article is about a reactor that does not use plutonium.

Yeah, but this subthread is about protest reasons :) The reactor in the article (and the half-life of it's fuel) can't be the reason people are protesting.

Re: NASA to test prototype Kilopower nuclear reactor

#100

Post by Manglano »

lloyd-christmas wrote: post #87
Manglano wrote: post #80

Earlier quoted context omitted.

US production has resumed, according to Wikipedia, as Cobalt 60 is coproduced and useful for medical sterilization. As an aside: There are some people who are very skeptical of both atoms and space exploration. I'm not sure what their motives are but given the amount of steel necessary to produce wind turbines, I'm unconvinced that "renewable" is actually "greener."

"over 20 years, a three-megawatt wind turbine can deliver 80 times more energy than is used in its production and maintenance." [0] Beyond that, Steel is 100% recyclable^, and that accounts for over 65% of US steel production. Recycled steel can be done in arc furnaces, requiring no coal coke. [1] Info like this is at the tip of your fingers. [0] https://www.worldsteel.org/en/dam/jcr:f07b864c-908e-4229-9f9... [1] htt…

Okay!

Downvote me if you like but our fuel mix in this country is still ~40% combustion and the calculations on wind power say that at current power requirements civilization will harvest enough energy from the air currents to change the climate again. Maybe it stops hurricanes, I have no idea.

Also, steel, like atomic fuel, is toxic to produce and reprocess!

I know it is much-despised by but I am curious as to the lifetime energy footprint of a fission reactor facility with onsite fuel-reprocessing and waste transmutation. And then? Tokamak. Won't even need a turbine!!

Parts of that system don't even exist yet but me I believe one day there will be clean atoms, fission or fusion, and they will require even less energy to produce and maintain than the wind and solar grid.

But then, I have lived among the fission reactors my entire life. Perhaps I am "mad from the rads" ;)

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