Thermal Decomposition of CO2 with Nuclear Heat
toughsf.blogspot.com
toughsf.blogspot.com
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.
https://en.wikipedia.org/wiki/AVR_reactor
and
https://en.wikipedia.org/wiki/THTR-300
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
https://en.wikipedia.org/wiki/HTR-PM
allegedly they use better fuel elements which are structured like a pomegrenade internally.
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.
https://www.forbes.com/sites/michaelshellenberger/2019/06/06...
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?
The Olkiluoto 3 plant in Finland was planned to open in 2011. It's still not running, massive cost overrun. https://en.wikipedia.org/wiki/Olkiluoto_Nuclear_Power_Plant
Flamanville in France was planned to open in 2012. Still not running, massive cost overrun. https://en.wikipedia.org/wiki/Flamanville_Nuclear_Power_Plan...
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.
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.
[1] http://folk.uio.no/roberan/img/GCB2018/PNG/s00_2018_Mitigati... [2] http://folk.uio.no/roberan/img/GCB2018/PNG/s00_2018_Mitigati...
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.
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.
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.
PS. It's fascinating to see Miami real estate prices completely ignoring the incoming doom: https://fred.stlouisfed.org/series/MIXRNSA
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.
Maybe in SV but not elsewhere. Plus servers that run 24x7 are probably the bulk of that 15%.
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.
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.
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.
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.
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.
Hydrogen is more efficient though.
It's awkward and relatively unsafe to handle, and has low energy density.
You'd be better off making eg synthetic petrol.
(I don't know enough about rocket fuel.)
Of course, making that plane fuel will cost energy. But probably closer to eg 2-3x the energy regained on burning than 10x.
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.
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.
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..)
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).
But so far without a carbon tax there hasn't been much incentive to reduce CO2 release in absolute levels.
A gram of carbon saved is equivalent to a gram of carbon captured.
> This problem could be avoided by limiting applicants to countries with the fossil fuel tax + import tariffs, and judging purely on carbon recovered.
I am not sure how that's avoiding the problem at all?
Btw, how would you judge the brilliant idea of growing trees?
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.
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.