This proposal requires imaginary materials straight out of comic book super-science. The proposed tantalum-hafnium-carbide material does have a very high melting point, but it will be destroyed by the molten uranium and its chemically diverse fission products.
If one were inclined to try to run "combustion in reverse" on a grand scale, to turn CO2 back into carbon and oxygen, the Bosch reaction seems a far more practical way to get there.
It runs at hundreds instead of thousands of degrees. The iron catalyst is cheap and abundant. The only required inputs are carbon dioxide and hydrogen. Since the reaction is thermodynamically spontaneous, the input gases can be produced from the cheapest available clean electricity (intermittent or otherwise) and stored in tank buffers.
CO2-to-graphite via the Bosch process would still be a project of breathtaking scale that would cost trillions of dollars. So it won't happen. But building a proof-of-concept would be affordable and straightforward, which is more than I can say for this nuclear-thermal decomposition proposal.
both pebble-bed reactors, where the first is some sort of superfund site, and the second tried to release some dust directly after chernobyl but got cought doing so.
OTOH China really seems to sample a bit of every tech it get
For a moment I wondered if the article was suggesting actually piping air through the reactor core - the accident at the Windscale plant in the UK demonstrating why that's maybe not such a great idea.
I feel like nuclear is the only (realistic) option we really have that'll help us navigate the gap between our current, and a more sustainable, less pollutant form of energy use.
It's a shame there's such a fear of it. I really think that most if not all energy efforts should be invested into nuclear immediately. That'll help buy us the time we need to get to sustainable renewables, or push us to master nuclear to the point that energy traded off against safety is no longer a concern.
It's probably too late for a full-on nuclear rollout. We need to reduce global carbon emissions really quickly, at least 5% (18%) per year starting right now [1,2] if we want a chance of staying below 2° (1.5°). Building nuclear power plants takes years even at the current rate of construction, if were to replace all fossil fuel by nuclear over the next fifteen to twenty years we would definitely run into capacity constraints, for example for manufacturing pressure vessels, or just having enough qualified personnel to build and run the things.
On the other hand, with the same money we could start building ridiculous amounts of wind, solar, and an improved grid and get immediate payoff, without having to wait years of unmitigated emissions for reactors to come online.
But what about the costs of energy storage to provide baseload capacity? And on top of that, if the goal is CO2 reduction, we need to generate 4x more electrical energy to replace fossil fuel chemical reagents and things like fertilizer production with non-fossil fuel sources that are far less 'efficient'. And that is before we start talking about future growth of electrical needs.
It won't be cheap, but neither will be the effects of global warming. The important question is whether it can be done or not, and on that front all signs point to yes.
Regarding storage, there is a tradeoff between an improved grid and storage requirements. It's always windy somewhere, if you have the grid to transport that power to where it's needed, you need much less storage.
> We need to reduce global carbon emissions really quickly...
I've been hearing this argument for at least 15 years now, and it's always followed by the assertion that nuclear plants are slow to build while solar and wind are quick to deploy.
And yet here we are, nothing has changed, the same arguments are repeated, only louder. Germany has shut down half her nuclear fleet, has very slowly built up renewable generation to maybe 30% of electricity production (only possible by abusing her neighbors' grid as a virtual battery), but has scarcely brought down her CO2 emissions, which are still more than twice those of France per capita.
And to think this blunder is celebrated as a success! It's not. If time was really of the essence, we'd do what France did between 1975 and 1985. Nuclear can be built quickly---they already did it, it can be done again.
Your math is off on the current scale of wind and PV and the time it takes to get it anywhere significant. Plus you are forgetting storage and infrastructure costs due to the intermittent nature of these sources and the imposed load factor. See https://jancovici.com/en/energy-transition/renewables/100-re...
The French government thinks they can make this transition and save 50 Billion compared with using nuclear. This blogger thinks it'll cost at least 10x more after doing some napkin math. Who do we believe?
One thing that puzzles me after reading that article: if the bodies of the men like Vasily Ignatenko weren't dangerous why did the authorities bury them inside zink caskets under a layer of concrete?
Edit: I guess one answer is that they were scared/ill-informed - but the Soviet authorities seemed to be doing everything they could do downplay the risks from radiation - so why would they do that?
This might sound cheeky, but it's a serious question: Where do you get this idea from?
There seems to be a lot of people who are strongly pro-nuclear primarily because they're pessimistic about renewables.
Whereas from my perspective, renewable tech is doing well enough that I consider climate change to be purely a political problem now.
Unfortunately that same politics has generated an absurd amount of informational chaff. There's multiple layers: climate change is a hoax, it's just cycles, it's actually beneficial, it won't be that bad, solar is a net waste of energy, you can't run a grid on more than 30% renewable and so on and so on.
It seems to me that the people that are enthusiastic about nuclear are coming from that same information bubble, possibly via American libertarianism, where they've been exposed to anti-renewable propaganda for years. They probably have internalized lots of misconceptions as a result. It's just that being vocally pro nuclear is a bit more of a rational and socially acceptable position to take than most of the other propaganda so as long as they stick to that it's hard to tell.
However, it's still wrong. I don't consider myself anti-nuclear, but it's just not the most cost effective way to generate low carbon energy. And that rollout of cheaper options would happen slightly faster if people like yourself (and Bill Gates) stopped acting like it was some impossible pipe dream and that we need to wait for nuclear to save us.
Not an expert, but right now I only believe in solar geo-engineering. And, of course, never buying a waterfront property, since at this point we'll almost certainly go above 2*C.
"baseload" is another shibboleth that suggests you're coming from some other information bubble, where that phrase has much more meaning.
I have no problem imagining renewable and storage taking care of baseload. Seasonal storage and winter peaks in cold climates and long distance flight are interesting problems. But meeting the baseload more economically than coal, gas or nuclear? Just roll out more of the tech we already have and which is already saving us money as we roll it out at smaller scales. Every small battery that replaces a horrendously expensive gas peaker plant is one step closer to the goal and generates savings we can spend on the next step.
This seems an unpopular opinion, but maybe we don't need more base load. Maybe we need more on availability load. With all the magic of connected devices, they could cope with varying electricity?
Of US Commercial electricity use about 40% is refrigeration, cooling, heating, and ventilation which can all time shifted at least intra-day with good building practices.
10% is lighting which realistically can't - you need lights when it's dark.
15% is computers which can sort of load shift because most office computers are now laptops - with good communications systems you can tell laptops how aggressively to charge / whether to run off battery.
The rest is "other" quite a lot of which is small electronic devices like tablets and phones charging and then a grab-bag of misc. stuff.
Half of residential electricity is some kind of temperature shifting (heating, cooling, refrigeration, freezers, ventilation).
Essentially with good insulation you can get to a point where you can load shift 50%+ of your electricity consumption on an intra-day basis.
Electric car charging of course is a perfect load to match to renewables as well.
That doesn't solve the issue of inter-day fluctuations - what happens when you have a cloudy, high pressure system sitting over a substantial part of your generation for a week - but it does mean that we can go pretty far. We may have to keep more open-cycle gas around for those times which will have to be funded on a capacity basis.
"with good building practices", "get to a point" this is planning an ideal future despite having a system where the legacy infrastructure very much still needs to be accommodated for. We can't disregard what already exists, and that involves a considerable amount of base load.
1) We don't yet have enough renewables for this to be an issue. Even with the most optimistic possible build-out timelines for additional renewable generation, we will not do so for another decade or two. That's why it's important to change building practices for new-build and refurbs now since the incremental cost for additional insulation is much less than the cost of retro-fitting.
2) "base load" isn't the best term here. Base load refers to the load that makes up the bottom of the load curve, basically a straight horizontal line right under the trough in demand. Some of base load actually is flexible load - for instance refrigeration equipment that runs overnight can be timeshifted by an hour easily (although in that case it is rarely done because power prices are cheap at that time). The problem for renewables is not base load but non-flexible / non-dispatchable load that must go on when requested such as lights or televisions.
Renewables meet the traditional concept of base load while generation is sufficient. This can be the situation often, or just occasionally depending on how many wind and solar facilities are present.
Renewable oversupply can already be economically stored for daily cycle purposes with 4 to 8 hour battery banks. If longer term storage is not developed, biomatter and synthetic fuels can run thermo-electric generators on the occasions that renewable supply falls short of demand.
Hinkley C in UK only could start construction because it got promised massive overpriced payment for electricity by the government. Speculation is this largely happens to cross-subsidize UKs nuclear weapons program.
This is all in countries that are politically relatively pro nuclear, this isn't because environmentalists are blocking the efforts.
Those articles indicate they are both partially running and both outputting more power right now individually, in their partially operational state, than any of the largest solar plants on earth. They also beat all wind plants except the largest.
But solar can be much more decentralised than nuclear. So comparing single plants by power doesn't seem fair to me, at the very least you also need to compare costs.
Decentralized solar also requires extensive upgrades and smarter and more robust electrical network. Electrical storage facilities will also still be centralized and you will have even more losses from bringing power in from long distances, and then releasing it back over similar distances again. A central plant is only one way, instead of both ways.
Looks like this guy really wants to build a vapor core reactor, but hasn't found a suitable problem it would solve.
If turning CO2 into graphite was a viable idea at all (it isn't, but that's besides the point), doing it purely thermally still wouldn't make sense. Even if the machines made of unobtainium existed, the dissociated gasses would just recombine when cooled down. It's much easier to operate at "low" temperature (say 1200K instead of 4000K, which is still a challenge!) and do it in multiple steps. But that is casually dismissed as slow and expensive in the article---I suspect, because it wouldn't need a vapor core reactor.
To be fair, when the dissociated gases recombined they would now likely have captured some neutrons, so it wouldn't be entirely without effect.
You'd likely end up emitting a lot of C-14 monoxide, which fantastically is both poisonous and radioactive.
I agree with a previous poster that the water electrolysis followed by the Bosch reaction would be a much more sensible approach. Of course it's unlikely that anybody will bother.
I was going to point out how crazy it is to even suggest that we'd install 10 times the total electrical generating capacity of mankind, in the form of imaginary reactor technology, just to scrub our existing CO2 emissions, but I think that might be the point...
Electricity generation is pretty cheap and doing it 10x more wouldn't be too hard. In fact if it fixed our CO2 problem, it would be an oustanding deal.
I suspect the grandparent was hinting that if we went ahead and generated 10x more electrical energy than now, we'd use it to just stop using fossil fuels entirely, rather than keep using fossil fuels and then pulling that CO2 back out of the atmosphere.
You can't stop using fossil fuels for everything just yet. Rockets, planes, still need fuels with high energy density - they won't run on batteries (at least with the current technology). There are of course other industries where fossil fuels are currently the basis for chemical reactions as well.
All solutions for large scale reduction of CO2 emissions are politically impossible, so some kind of carbon capture is probably the only thing that could save us. It's unlikely to work, but we should at least incentivize trying.
I suggest taxing all fossil fuels sufficient to cause a compounding 10% price rise per year, and applying an equivalent tariff based on estimated embodied energy from fossil fuels to imports from countries that don't apply the same tax. All the money goes into a prize fund, and anybody can claim a share of it in proportion to their share of net CO2 removed from the atmosphere out of the total verified claims of net CO2 removed that year (paying an application fee sufficient to cover third party verification of their claim).
Anybody anywhere in the world can claim, and you could win the entire multi-billion dollar prize with a single gram of carbon if nobody else claimed. This would strongly encourage competition.
You start by talking about political impossibility, but then propose an even more outlandish scheme.
Applying CO2 tax as a consumption tax like VAT seems like a feasible solution.
Your prize fund, less so. But it's not needed. The tax take can just finance government in general. Companies will have plenty of incentive to reward inventors for lessening their tax burden.
Your proposal will only result in moderately reduced emissions, which isn't enough. We need zero, or ideally negative emissions, which the prize fund idea has a chance of providing.
How much emissions reduce depends on how high the tax is, how well it is enforced, and how easy the divers technologies and trade-offs to reduce emissions work in practice.
On the one hand, if the tax worked perfectly, emissions would cease completely, and there would be no prize money funded.
On the other hand, if there was a lot of tax take, that would be a big incentive for companies to do their own research and put up prizes.
Government picking winners in such a beauty-contest competition is inherently dangerous.
Eg one obvious 'idea' is to just reduce your consumption, like driving less. Or running your aircon less often and only at higher temperatures.
Those ideas are very effective, but are their prize worthy?
The only prize worthy aspect of them would be in the social science / propaganda necessary to get many people to adopt them. How are you going to judge that? (And in that case, the politicians who voted for the carbon tax can arguable claim the biggest part of that prize..)
If emissions cease completely then there's much less need for the prize fund. The point of the prize system is that it avoids the government picking winners. The money is distributed by objective measurement. But admittedly "net removed carbon" (meaning carbon removed from the air - carbon released into the air by the removal process) has some subjectivity in the "by the removal process" part. What qualifies as part of the process? This problem could be avoided by limiting applicants to countries with the fossil fuel tax + import tariffs, and judging purely on carbon recovered.
Just reducing consumption is not pulling carbon out of the air so it would score zero, and it's a highly ineffective solution (we've been trying it for decades, but CO2 levels keep increasing).
The reason I said "net carbon captured" was to avoid the "cobra effect" of people releasing carbon deliberately so they can capture it, or of people using fossil fuel powered carbon capture that releases more than it captures. If they are paying high taxes on fossil fuels then it will quickly become unprofitable, so in that case it's not a serious problem.
Assuming they are not later burnt, growing trees qualifies as carbon capture. I now realize the tax would have to be on all forms of CO2 emissions, not just fossil fuels, otherwise the captured carbon would be re-burned.
This amounts to using nuclear power to unburn carbon in the atmosphere, which is possible I’m sure, but the total loop efficiency of burning then unburning carbon is less than if you just never burned it in the first place.
TL;DR; If we overcome massive engineering challenges (such as capturing CO2, crafting materials that handle nuclear reaction at very hight temperature and manage to successfully confine all irradiated byproducts) we could theoretically decompose CO2 using nuclear reactors to overcome global warming.
My comment: Or maybe, just maybe we could plant a shitload of well chosen/engineered trees and algae that do the whole processes autonomously with less risks. And of course reduce current consumption is needed in every scenario.
Wait a minute, if we can just extract co2 from the air like in step 1, why don't we just stick it in a container somewhere? It's the atmospheric co2 that's the problem, right?
If one were inclined to try to run "combustion in reverse" on a grand scale, to turn CO2 back into carbon and oxygen, the Bosch reaction seems a far more practical way to get there.
https://en.wikipedia.org/wiki/Bosch_reaction
It runs at hundreds instead of thousands of degrees. The iron catalyst is cheap and abundant. The only required inputs are carbon dioxide and hydrogen. Since the reaction is thermodynamically spontaneous, the input gases can be produced from the cheapest available clean electricity (intermittent or otherwise) and stored in tank buffers.
CO2-to-graphite via the Bosch process would still be a project of breathtaking scale that would cost trillions of dollars. So it won't happen. But building a proof-of-concept would be affordable and straightforward, which is more than I can say for this nuclear-thermal decomposition proposal.