Safe, TL 7 suitcase sized nuke power plant, for real.
- Thread starter DFW
- Start date
RTG reactors have been used for decades on space craft. I think it was Green Peace who tried to stop one of the planetary probes from launching from Canaveral because it carried a plutonium - powered RTG and they were worried about the risk if the rocket crashed.
Granted, plutonium in the Atlantic is not to be trifled with, but the casings are designed to take quite a beating. And that far from the sun solar power is next to useless.
Granted, plutonium in the Atlantic is not to be trifled with, but the casings are designed to take quite a beating. And that far from the sun solar power is next to useless.
DFW said:phavoc said:
This isn't an RTG reactor.
Here's a cutaway of one:
Huh? According to the Wiki entry at http://en.wikipedia.org/wiki/GPHS-RTG, which shows that same illustration, it is an RTG (or more properly a General Purpose Heat Source Radioisotope Thermoelectric Generator).
I followed the link on the page referenced by DFW. According to the Wiki entry for the rover says the power source is, in fact, a RTG:
Power source
The Curiosity rover will be powered by radioisotope thermoelectric generators (RTGs), as used by the successful Mars landers Viking 1 and Viking 2 in 1976.[29][30] Radioisotope power systems are generators that produce electricity from the natural decay of plutonium-238, which is a non-fissile isotope of plutonium used in power systems for NASA spacecraft. Heat given off by the natural decay of this isotope is converted into electricity, providing constant power during all seasons and through the day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments.[29][30]
The Curiosity power source will use the latest RTG generation built by Boeing, called the "Multi-Mission Radioisotope Thermoelectric Generator" or MMRTG.[31] Based on classical RTG technology, it represents a more flexible and compact development step,[31] and is designed to produce 125 watts of electrical power at the start of the mission and 100 watts after its minimum lifetime of 14 years.[32][33] The MSL will generate 2.5 kilowatt hours per day compared to the Mars Exploration Rovers which can generate about 0.6 kilowatt hours per day.[13]
Power source
The Curiosity rover will be powered by radioisotope thermoelectric generators (RTGs), as used by the successful Mars landers Viking 1 and Viking 2 in 1976.[29][30] Radioisotope power systems are generators that produce electricity from the natural decay of plutonium-238, which is a non-fissile isotope of plutonium used in power systems for NASA spacecraft. Heat given off by the natural decay of this isotope is converted into electricity, providing constant power during all seasons and through the day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments.[29][30]
The Curiosity power source will use the latest RTG generation built by Boeing, called the "Multi-Mission Radioisotope Thermoelectric Generator" or MMRTG.[31] Based on classical RTG technology, it represents a more flexible and compact development step,[31] and is designed to produce 125 watts of electrical power at the start of the mission and 100 watts after its minimum lifetime of 14 years.[32][33] The MSL will generate 2.5 kilowatt hours per day compared to the Mars Exploration Rovers which can generate about 0.6 kilowatt hours per day.[13]
Well... to be fair it's made out to be not much more than a concept at the moment.
It's not impossible - critical mass for uranium is in the order of fifty kilos or so give or take design features.
There's one thing not made clear - I found a second version of the article here .
The thing that's not clear is how they actually intend to turn the output into electricity. A suitcase sized core is fine, I'll buy it. But unless they have a suitably clever concept to go with it, it's not a generator, it's just a portable source of radiation sickness. It's possible you could do something with a thermoelectric effect (just using a fissioning core for the heat, rather than the warmth of 'natural' decay like an RTG) but I don't think they're supposed to be very efficient.
On the other hand, with space as your 'cold' source, and a critical nuclear sphere for the 'hot' source, you'll get a fairly impressive temperature difference.
The use of liquid metal cooling makes sense - it means not having to have the vessel under pressure (since building a pressure vessel eliminates any real space advantages of a small core) but it's going to cause some problems with design and maintenance.
Indeed. If the damn thing is designed to survive an uncontrolled and uncommanded re-entry without leaking (which it was), I don't see what the problem is. To be honest, if a probe crashed, the release of rate earth metals from the electronics and invasive fibres from CFRP and BFRP will do far more damage to the local environment than any putative radiation leak. Not that that's probably going to help much as an argument.
It's not impossible - critical mass for uranium is in the order of fifty kilos or so give or take design features.
There's one thing not made clear - I found a second version of the article here .
The thing that's not clear is how they actually intend to turn the output into electricity. A suitcase sized core is fine, I'll buy it. But unless they have a suitably clever concept to go with it, it's not a generator, it's just a portable source of radiation sickness. It's possible you could do something with a thermoelectric effect (just using a fissioning core for the heat, rather than the warmth of 'natural' decay like an RTG) but I don't think they're supposed to be very efficient.
On the other hand, with space as your 'cold' source, and a critical nuclear sphere for the 'hot' source, you'll get a fairly impressive temperature difference.
The use of liquid metal cooling makes sense - it means not having to have the vessel under pressure (since building a pressure vessel eliminates any real space advantages of a small core) but it's going to cause some problems with design and maintenance.
Indeed. If the damn thing is designed to survive an uncontrolled and uncommanded re-entry without leaking (which it was), I don't see what the problem is. To be honest, if a probe crashed, the release of rate earth metals from the electronics and invasive fibres from CFRP and BFRP will do far more damage to the local environment than any putative radiation leak. Not that that's probably going to help much as an argument.
I guess the problem was that a Russian RTG supposedly designed tolocarno24 said:
survive an uncontrolled re-entry without leaking crashed in Canada,
Greenpeace's home nation, and split open. Since Greenpeace does
not trust any government further than they can throw it, the US as-
surances that the RTG was safer than its Russian counterpart did
not convince them. Besides, the protest got wide attention and ear-
ned them a lot of donations.
phavoc said:
:roll:
No, not what you are writing about. Reread the tech until you understand the difference between RTG's and a nuclear power station using a generator, a machine that converts mechanical energy into electrical energy by creating relative motion between a magnetic field and a conductor. ...
DFW said:
Ah, ok. I see where I was making my mistake. You are correct. The RTG is different beast. I found another article for this that went into more detail - http://idealab.talkingpointsmemo.com/2011/08/nasa-testing-suitcase-sized-nukes-to-power-colonies-on-remote-planets.php
