Andreas Kaubisch wrote:"And finally, not a battery at all, are projects like the Kilowatt. A 1 to 10K thermonuclear generator being developed by NASA for use off world. They last 10 years... at full output, but can be throttled. Probably safer than any of the batteries discussed above. Capturing the waste heat rather than radiating it would probably double it's effective output. Sunshine or rain not a problem, no snow removal needed. I suspect the liquid salt reactor would be too big for the average homestead, but probably ideal for a small community. (it would also be an ideal place to get rid of spent fuel from kilopower generators used on local homesteads."
'thermonuclear generator' - what are the waste products of this process? Something radiocative?
Also not sure about the wisdom of putting thermonuclear devices in the hands of homesteaders all over the world.... maybe I am not clear on the technology you are referring to?
Thermonuclear power production has gotten off to an unfortunate start. Research in this area is costly. The only reason it got that funding is because of wartime needs (like the bomb) Further funding was done to get nuclear powered submarines. There was other development ongoing into molten salt reactors but that was shutdown once there were nuclear powered sub in place and it was obvious the same process could be used in civilian power production. This was a political
decision and in my opinion a bad one. Using water based cooling
in the middle of the ocean in a sub or even a surface vessel makes lots of sense but all three major nuclear power plant accidents have been steam explosions. Water cooled nuclear power plants absolutely must have outside power at all times to be run in a safe manner... as we have seen in Japan there can never be a guarantee of that outside power. Both the kilopower and the molten salt reactors mentioned above do not have this problem. They have a gravity based (or in the case of a microgravity kilopower unit, spring based) method of safe shutdown that will happen all on it's own with no human intervention. Heat opens a valve and the fuel or moderator drains or falls away, completely shutting the plant down safely. The generator can sit in this emergency shutdown mode without any attention and no radioactive emissions for years. So in a case like Japan, the energy spent evacuating away from the power plant (this evacuation cased more deaths than the powerplant failure) could be spent on more important emergencies. I have covered emergencies and harm that could be done first because that is the area the fearmongers spend most of their time on.
Waste disposal in the case of the kilopower is similar to lead acid batteries. The unit is sealed and after 10 to 20 years the whole unit is recycled in the same way as lead acid batteries.... they are taken back where they came from. I would imagine a deposit would be large enough
to make it worth while for the user to do so. I don't know about other countries, but lead acid batteries can be returned to anyplace that sells them where I live. Liquid salt reactors, as I said, are a bit too big for the average homestead at 500kw, but they do have the advantage that they truly use up all the fuel they are given and in fact are quite happy to use the waste product of other nuclear processes as fuel. So they would be quite happy to eat up all the "spent" fuel from our current inefficient water based nuclear power plants. They would be quite happy taking the fuel from decommissioned weapons as well. As output, they can provide medically important materials at a fraction of the cost of current processing. The remainder after all is finished is much smaller than current generation plants... in fact the radiation from the byproducts is less than the radiation from smoke emitted from coal burning power plants we have now. So in the same way that all off grid power supplies have waste be it wind generators, solar panels, batteries or whatever, they all have a life time and a waste cycle but in the case of a kilopower type of generator the energy to recycle would be less and the spent fuel would be fuel for another process that is environmentally "friendly". I think that when properly compared to all the other homestead power solutions, taking into account the whole life cycle, small nuclear power generation is no worse and possibly better than most other methods. I would add to that nuclear power generation is in its infancy. work had stopped up until only a few years ago because government funding stopped and even as development has restarted in many parts of the world (the US is behind these days) the biggest problem is not the technology, but regulations based on light water power plants. (ok, politics)
Some other advantages of some of the new nuclear processes: North America has stopped mining rare earth materials because of the byproducts. These same byproducts happen to be the needed starting point for these nuclear processes. In case it has been missed, rare earth materials are used in almost all small and large electric motors that make the best replacements for internal combustion engines.
The truth is, if there is electricity on any homestead, that homestead is reliant on modern technology and modern waste products that require off homestead disposal as well as production. One of the things that scares me about lithium based home power is that there is the assumption the end product is benign and is safe to just leave lying around.... In the end, the question very quickly starts to become, do any of us really know what we are talking about?
Thanks for a great question. The answer
for the most part is that the technology is not yet ready for use off world use (where money is no object) and probably a long way off before terrestrial use is happening at all let alone common place. However, I firmly believe that if we wish to keep our shorelines sort of close to where they are, it is going to take nuclear power, particularly in the third world countries where the difference between poverty and not, is readily available power. This is not about human caused climate change, climate will change if we are here or not and it will take technology of some sort to keep our world livable.