[Schroedingersat]

> Was this due to a sudden increase in reactor construction?

Mild delay in a mine opening. A sudden increase in reactor construction would be much worse.

> This is a distinct advantage over wind and solar that do not directly produce thermal energy and have to be converted from electricity to thermal energy.

CSP exists and is going down in price rapidly.

> Sulfuric acid is widely used for plenty of things like fertilizer production, hydrocarbon refining, and car batteries. An 8x increase in nuclear power wouldn't substantially affect the markets for these resources

1kg of Uranium from inkai or husab uses 50-100kg of sulfuric acid. And this is high grade compared to the 600,000 tonnes per year you are proposing using. Doubling world sulfuric acid production is about the right magnitude.

> uranium seawater extraction has been successfully performed

Make up your mind about what is possible and what is impossible. If doing it once to publish a paper and then pencilling out the costs of raw materials counts then we can all just use AlS batteries and go home.

> This is not how seawater extraction works. The same mass of adsorbent won't collect larger quantities of other elements. The 6 grams of uranium collected per kilogram of adsorbent doesn't turn into a 6 kilograms of material per Kg of adsorbent for a material that's 1000x as concentrated in the ocean. It will fill up faster for a more concentrated element, but you're still retrieving similar amounts of material for the same amount of adsorbent. You have to make 1000x as many trips to collect 1000x as much material, regardless of concentration.

> The cost of this extraction is entirely comprised of deploying and retrieving the adsorbent material - letting a buoy sit in the ocean for 2 months instead of 1 week costs nothing. This is why seawater extraction is prohibitively expensive for most applications, uranium's incredible energy density is what makes it a viable application.

Natural Uranium in a burner reactor is not very energy dense in the scheme of things. Much higher than coal, but about the same power output as a similar mass of silicon in a photovoltaic cell (but at 75% CF for 6 years rather than ~15-25% for 30-50).

At ~3g/kg the uranium only has about 10x as much energy as you'd get by burning the polymer or 5x in the current nuclear fleet (wonder how much it takes to make?). There goes the much vaunted EROI unless you get quite a few reuses (hint: you only get a few).

Also what I said is exactly how sea mining works. Please at least try to understand these technologies before pushing them. You get more vanadium than Uranium in any realistic use case https://www.osti.gov/pages/biblio/1234341

The longer you leave it, the more Uranium gets displaced by Vanadium. At 2 months you get 5x as much.

1kg of natural uranium has a power output of about 1-2kW for 6 years and then it's gone. 1kg of vanadium can store 350-650Wh.

Such a simple plan with so few completely deal breaking oversights compared to building sodium ion factories which is already happening and building more pumped hydro which we know how to do.

[Manuel_D]

> at ~3g/kg the uranium only has about 10x as much energy as you'd get by burning the polymer or 5x in the current nuclear fleet (wonder how much it takes to make?). There goes the much vaunted EROI unless you get quite a few reuses (hint: you only get a few).

Except the polymer is re-usable.

> The longer you leave it, the more Uranium gets displaced by Vanadium. At 2 months you get 5x as much.

Until it's saturated, then you can leave it out all you want and it won't collect any more. And I had thought you were referring to lithium seawater extraction - you just tossed out vanadium without actually explaining how you'd use it and I assumed you mistyped lithium.

Unfortunately vanadium redox batteries are not nearly built at the scale of lithium batteries - which are themselves not built at a scale large enough for grid storage - as well as poorer round trip efficiency.

[Schroedingersat]

> Except the polymer is re-usable.

A few times: https://www.ornl.gov/publication/investigations-reusability-...

As I said, there goes your eroi. At 10mg/kg you're producing 10,000 tonnes of polymer per year per reactor and harvesting it 3-6 times. This is supposed to be economical? That's 10 million tonnes of plastic waste per year just for one terawatt or 10% of world plastic waste to replace FF electrical generation.

> Until it's saturated, then you can leave it out all you want and it won't collect any more.

If you leave it in too long the Uranium starts going out because Vanadium has higher concentration and similar affinity. But long before that, your polymer breaks down and becomes microplastic pollution.

> Unfortunately vanadium redox batteries are not nearly built at the scale of lithium batteries - which are themselves not built at a scale large enough for grid storage - as well as poorer round trip efficiency.

So now we're back to this incoherent dissonance where doing something once on a tiny test platform makes it a definite solution to world energy, but something being produced at GWh scale in the real world is not big enough? That's a truly stellar amount of double think you've got going on there. I'm sure there'll be even more interest when your magic $20/kg unlimited supply vanadium machine running at 20x current total production is up and running.

[Manuel_D]

> A few times: https://www.ornl.gov/publication/investigations-reusability-...

The adsorbent loses efficiency after a couple elution cycles, but it is regenerated by an alki wash. Read this [1] if you want a better explanation. No, you do not need to keep producing tons and tons of polymer. You have to treat it with chemicals after a couple cycles, but you don't need to throw the whole polymer away and start anew.

Regardless, this whole seawater extraction tangent is only a contingency if no new terrestrial reserves of uranium are found. Unlike intermittent sources which require massive amounts of grid storage, uranium seawater extraction isn't going to be necessary any time soon which is why I'm not super concerned about how seawater extraction isn't being commercialized.

On the other hand, renewables are already starting to saturate the market during peak production today. In order to make intermittent sources viable we need storage systems now. It's not dissonance, it's the fact that there are presently functioning alternatives to seawater extraction that will continue to work for the near to mid term future. Whereas there are no storage systems capable of delivering energy at grid scale.

1. https://www.osti.gov/servlets/purl/1423067

[Schroedingersat]

> The adsorbent loses efficiency after a couple elution cycles, but it is regenerated by an alki wash. Read this [1] if you want a better explanation.

..The longest lasting method in that paper is a scale model in idealized conditions of the same method I linked to but the first was in more realistic conditions... they ran one in the ocean but not more than once.

> Regardless, this whole seawater extraction tangent is only a contingency if no new terrestrial reserves of uranium are found. Unlike intermittent sources which require massive amounts of grid storage, uranium seawater extraction isn't going to be necessary any time soon which is why I'm not super concerned about how seawater extraction isn't being commercialized.

So we're back here. To match the scale of renewable when they start to run into the constraints that require scaling up storage, you need about 3TW by 2030 (before then a mix is viable along with using surplus for replacing non-electrical fossil fuels such as H2). That's 10,000 tonnes of fissile material up front, and another 10,000 every reload. You need to open every mine on the planet today and empty them by 2040. Then your sea mining rig needs to be ready to go (and hilariously has to be installed on a greater net capacity of offshore wind turbines than the capacity of nuclear reactors it supplies). After that you still need just as much storage for variable loads because ramping isn't an option as idle capacity would reduce your fuel runway by 6 years.

All this because you think lithium production can't double when the extraction started a year ago? It's actually a comically bad plan. Well done. The bit where it needs the wind turbines was comedy gold.

[Manuel_D]

> ..The longest lasting method in that paper is a scale model in idealized conditions of the same method I linked to but the first was in more realistic conditions... they ran one in the ocean but not more than once.

Sure, they may need to regenerate the adsorbent after just one use. But the polymer survives. Even if the adsorbent retains most of its efficacy after one elution cycle, it could be more efficient to refresh it to maximize the material collected per trip. You seemed to have been under the impression that the entire polymer needed to be replaced when you talked about how it'd be more effective to burn the polymer: "at ~3g/kg the uranium only has about 10x as much energy as you'd get by burning the polymer or 5x in the current nuclear fleet"

For what it's worth I am confident that lithium ion battery production will continue to increase and double, triple, or even quadruple over the next century. But that will be barely enough just to satisfy EV demand for batteries. Even just provisioning 12 hours of grid storage worldwide would need 30,000 GWh at present electricity demand. That's close to a century of production at present rates. Doubling, tripling or even quadrupling production still means we'd need to dedicate several decades worth of battery production just to satisfy 12 hours of present electricity demand. Not to mention the fact that electricity demand is going to increase as more transport moves to EVs and as poorer countries develop. Not to mention the fact that these batteries need to be replaced after a few thousand cycles.

I'm confident about battery production doubling or tripling, it's the factor of 10 to 20 that I'm more skeptical of - and that's the kind of increase we'd need to make battery grid storage feasible.

[Schroedingersat]

The polymer is the sorbent. Please actually read the sources you send. Normally it is on a higher strength belt, but this scheme puts it in a plastic shell. That's the bit their charts show with tens of thousands of tonnes needed per fuel load (which turned out to be optimistic when someone checked).

> For what it's worth I am confident that lithium ion battery production will continue to increase and double, triple, or even quadruple over the next century. But that will be barely enough just to satisfy EV demand for batteries. Even just provisioning 12 hours of grid storage worldwide would need 30,000 GWh at present electricity demand. That's close to a century of production at present rates.

You're off by over a factor of 3. There's around 1TWh/yr now, and 5TWh/yr under construction due before 2030. And only a few hours needs to be high power. The rest can be thermal, PHES, CSP dispatch, virtual batteries via load shifting, hydrogen for emergencies, and so on.

> I'm confident about battery production doubling or tripling, it's the factor of 10 to 20 that I'm more skeptical of - and that's the kind of increase we'd need to make battery grid storage feasible.

It's happened, if it were a nuclear project then it'd be at the stage where they've already declared it finished, but shut it down straight after loading and said it will reopen in a month. Other industries do things a little differently, but either way it'll mostly be running around 2028

[Manuel_D]

> CSP exists and is going down in price rapidly.

Quite the contrary, CSP fell out of favor because PVs outcompeted it. What is making CSP better? Did mirrors suddenly improve?

> 1kg of Uranium from inkai or husab uses 50-100kg of sulfuric acid. And this is high grade compared to the 600,000 tonnes per year you are proposing using. Doubling world sulfuric acid production is about the right magnitude.

Did you just pick these figures out of thin air? Reduction of uranium in sulfuric acid is nowhere near 100 : 1 ratio. Unless you're talking about 600,000 tons after enrichment, in which case your figure for uranium consumption is off by an order of magnitude. A 1 GW reactor requires 27 tons of uranium per year [1]. The world uses an average of 2,500 GW of electricity meaning we'd need 68,000 tons of uranium fuel per year. The world produces 231 million tons of sulfuric acid annually [2], so even if we run with your un-sourced numbers this only requires an increase of 2-3%.

> At ~3g/kg the uranium only has about 10x as much energy as you'd get by burning the polymer or 5x in the current nuclear fleet (wonder how much it takes to make?). There goes the much vaunted EROI unless you get quite a few reuses (hint: you only get a few).

Except unlike solar power, the nuclear fleet doesn't require vast amounts of energy storage. It produces the amount amount of electricity regardless of sunlight or wind speed.

Here's the future of renewables: We keep building it opportunistically to displace natural gas. But once they saturate markets during peak production, they become far less effective at displacing carbon emissions because most of their energy is wasted.. After some time scratching our heads struggling to build energy storage at anywhere near relevant scales, we realize that dispatchable energy is necessary and we build it the only ways we know how: hydroelectricity where geography permits, and nuclear power. Or we can jump straight to the the last part and skip building a bunch of intermittent generation that will be made redundant in the end anyway.

1. https://world-nuclear.org/nuclear-essentials/how-is-uranium-...

2. https://www.essentialchemicalindustry.org/chemicals/sulfuric...

[Schroedingersat]

> What is making CSP better? Did mirrors suddenly improve?

Yes. Thanks for noticing: https://www.reutersevents.com/renewables/csp-today/self-alig... I think the first projects using them are just about done. Heliostats now require much less foundation and are much cheaper to install. The remaining portion is almost identical to the cheap part of many of the SMR concepts, but on a stick instead of in a gigantic steel and concrete room.

But the main driver is actually that it is dispatchable. If you make the hot bit bigger and combine it 5:1 with PV with a little battery on the side you get a millisecond response, grid forming, 24/7 dispatchable power station that is presently about the same price as a NPP but is actually going down rather than up. They're only good in low clous regions, but there is enough good resource for it to make a contribution on the same order as nuclear.

> Did you just pick these figures out of thin air? Reduction of uranium in sulfuric acid is nowhere near 100 : 1 ratio. Unless you're talking about 600,000 tons after enrichment, in which case your figure for uranium consumption is off by an order of magnitude. A 1 GW reactor requires 27 tons of uranium per year [1]. The world uses an average of 2,500 GW of electricity meaning we'd need 68,000 tons of uranium fuel per year. The world produces 231 million tons of sulfuric acid annually [2], so even if we run with your un-sourced numbers this only requires an increase of 2-3%.

It's for getting it out of the ore at 1-3ppt. Do you not even understand that not all uranium resource is like cigar lake where you just find some yellow and green rocks, pour a bit of heavy water on them and call it good? Go look at the sulfuric acid consumption of rossing or inkai, realise those are high concentration compared to the other 7 million tonnes and lower concentration needs more, then come back and apologise.

Most of the ore you are proposing mining is no more energy dense than oil.

> Except unlike solar power, the nuclear fleet doesn't require vast amounts of energy storage.

One kg of natural uranium cannot produce enough energy to wear out an LFP battery made with 1kg of lithium -- and the lithium can be recycled. I think we're good.