Posted on 10/27/2025 10:30:06 AM PDT by rlmorel
“Any idea how the energy storage thing works?”
Molten salt reactors are perfect for wait for it molten salt thermal energy storage. The secondary salt loop is not radioactive so you take heat from that loop using the same salts you would for solar thermal energy storage typically a fluoride based salt two tanks one screaming hot from the reactor heat the other molten but only a hundred ish degrees above freezing temps. Fill up hot tank with excess nuclear heat then when you need it pull it out and spin up some turbines with that heat, steam or better yet supercritical CO2 turbines that hit 48% thermal to electrons efficiency vs 33% for steam turbines.
There are other ways geothermal energy storage is another way cubic miles of “earth battery” you could put thousands of gigawatt hours down into the heat bank, store it for years too the heat flux at depth is slow over the distances involved.
In fact this type or Geothermal energy storage works for any energy source you can use joule heating of the fluid directly via electrons sourced from any source if they are cheap enough off peak wind, solar during the blazing Sun of midday when it’s curtailed as the grid cannot use all of it, off peak nukes not right next to the energy storage well bores take the electrons from the high voltage lines and joule heat the supercritical CO2 or steam and push it down the well bores. With modern directional drilling and hydraulic stimulation aka fracing you can access cubic miles worth of now permeable and porous strata. Yes I am a geologist PhD level at that.
https://dspace.mit.edu/handle/1721.1/75125
"...Yes, Natura's MSR-1 Gen IV reactor is designed as a small modular system whose components can be fabricated in a factory and shipped to sites via truck (or rail) for assembly and deployment. This modularity is a core feature, as confirmed by Natura Resources' development plans for the MSR-1 demonstration unit at Abilene Christian University and its scalable follow-on MSR-100, which lowers costs compared to traditional reactors. The MSR-1 itself, a 1-MW thermal liquid-fueled molten salt reactor, aligns with this transportable design, enabling efficient deployment starting in 2026..."
The MSR-1 is the pilot unit, and the MSR-100 will use the same concepts of modularity to ship. That is huge.
Thanks. Good explanation.
I think “a few” 18-wheel flatbeds...:)
You also don’t have to drill well bores you can go in the other direction and use liquid air for thermal storage of energy it’s dense and doesn’t need any special geology near by. The waste heat from the turbines is what you use to warm up the liquid air it improves the efficiency drastically too.
https://www.sciencedirect.com/science/article/abs/pii/S0306261913007216
https://ideas.repec.org/a/eee/appene/v113y2014icp1710-1716.html
https://www.asme.org/topics-resources/content/storing-heat-nuclear-power-plants-could-improve
You can also use high pressure water injection down a well bore again into an “earth battery” running 15 megawatt sized pumps at 10,000+ psi when you need power open the spigot and the water comes rushing back out spinning those same pumps as turbines and those 15 megawatt motors as 15 megawatt generators. Round trip is in the 80% range efficiency and if you get the geothermal heat top then it’s over 100% since you are also heat mining from the geothermal gradient.
I personally have worked with Sage on this project. I do SWD wells in the Permian and that is where the idea came from.
https://newatlas.com/energy/sage-geosystems-huff-puff/
Here again the tech doesn’t care where the electrons come from nukes sure why not, off peak wind you betcha, curtailment solar yeah buddy ERCOT last week was at $1.38 per megawatt hour for 4 hours from 0900 when the Sun came up till 1300 ish a few days in a row. That’s 0.14 CENTS per kilowatt hour under 1/10th of a cent you would make gang busters money buying wholesale power at that price and selling it 8 hours later when the gas turbines spin up at 2000 and the minimum price is $50 per megawatt hour set by the cost of the natural gas to fuel those turbines at $4 MMBTU you cannot sell for less than $35 and turn positive revenue.
Course China is kicking butts and taking names in energy storage they have a 14 megawatt hour pack that fits in a standard 20 foot ISO container....
https://interestingengineering.com/energy/china-byd-dc-battery-block
“The Haohan system is built around its own 2,710 Ah Blade Battery cell, which the company calls the world’s largest for energy storage. This cell delivers triple the capacity of typical storage batteries, offers more than 10,000 charge–discharge cycles, and cuts lifetime energy costs to under $0.014 per kilowatt-hour – a figure that could transform the economics of grid-scale projects. “
1.4 CENTS per kilowatt hour levelized cost of storage read that again to fathom the paradigm shift this represents. Wholesale ERCOT rates are regularly in the $10-15 per megawatt range that’s 1 -1.5 cents per kWh putting it into a pack such as this one is 95% round trip efficient. @$15 MWh that’s 1.57 cents plus 1.4 cents storage for 2.97 cents per kWh you can sell that retail today for 12 cents per kWh it should be crystal clear why Texas has 13,000+ megawatts worth of megapacks and will have 30000+ by 2030 gang busters money being made and that CATL/BYD pack is game changing it’s 10,000 cycles which is 27 YEARS of once per day cycling and the lifespan is to 80% original capacity not zero. Two words game changer. Storage that cheap means solar at 3/10th of a cent per kilowatt hour of electrons in wholesale panel capital costs is THE cheapest form of electrons humans have come up with period full stop. Having a megapack at 1.4 cents per kWh is $14 per megawatt hour and solar can turn profits at $10 per megawatt hour that’s $24 per megawatt hour and with a pack that sized who cares when the sun sets you can put days worth of energy storage away at costs that low. CATL is going to laugh all the way to the bank and so is every one who uses those packs for power arbitrage $$$$$$
The very earliest molten salt reactors were running at power back in the 50s. Several versions worked adequately - including the first Seawolf Navy reactor, but at the time, their advantages just didn’t make economic sense.
There are real world problems, but they can be safely solved.
I would like to be on that future ping list, sir.
The molten sodium cooled reactor in the USS Seawolf was very cool in many respects-it used electromagnetic pumps to circulate the coolant which had the very desirable side possibility of making it extremely quiet with no impeller or moving parts, but...the stories I read about the molten sodium coolant, especially if it came in to contact with WATER (I know-in a submarine!) were absolutely hair-raising!
During maintenance, they had to use sodium hydroxide as a solvent on any part of the cooling system to take off the solidified molten sodium, and there were a few BIG explosions when she was in the yards having work done.
Makes me shudder to think of.
There was a lot of technology that was relatively immature
I recall there was one accident where the solidified sodium coolant had collected inside some drain from the pipes in the system they performed maintenance on the sodium-beryllium metal covered parts on (they used high pressure hoses that they could spray the parts with sodium hydroxide, and it left them as clean as a whistle with no residue) and when someone was cleaning one of those systems, they ran water down the drain (It was only supposed to have sodium hydroxide in it) it came into contact with the sodium-beryllium solids deposited in there and they had an explosion!
This is an Austin company they are building the first sodium reactor in 30+ years in the USA with Livermore National laboratory they have NRC approvals and gave their factory ready to mass produce these bad boys.
Sodium cooled, CO2 or steam turbines ,the CO2 version is dry cooled no water needed so arid and semi arid is fine.
Sodium pool reactors cannot melt down at small sizes they passively air cool well below the boiling point of molten sodium.
Using CO2 secondary loop eliminates any possibility of a sodium water reaction and the whole unit is in an argon atmosphere so it’s inert already.
Sodium cooled means you can and they plan on removing the sodium hydroxide moderator and going to what every reactor from now on should be a fast spectrum breed reactors. Sodium with uranium/Pu metal fuel clad in cheap stainless vs Gucci expensive zirconium can do breed ratios up too 1.4 that’s 40% more fissile material comes out vs what you started with it should be obvious why this is good.
A single gram of U238 turned into Pu239 has 82 gigajoules of energy or equal to 77.721004 MMBTU of natural gas.
A single Kg of Pu239 is thus 77721 MMBTU of natural gas which at $4 MMBTU would cost $310,884 worth of natural gas
A breed reactor is literally a money machine just in Pu alone.
My personal fave is a D-D catalyzed fusion fission hybrid breeder 8,000 Kg of Pu 239 per year for a single unit and you only need a C0.3 not breakeven of C1 this means humans which have just barely hit C1 already can do fusion fission hybrid today nothing new is needed only the will to do so. The USA is scared of Pu239 fortunately the Chinese, Russians, French, Israeli and Britain are not afraid of a plutonium economy. So as a species we good. The Russians and the Chinese both have active breeder programs and huge reprocessing centers we flatly are begin left behind.
https://apps.dtic.mil/sti/tr/pdf/ADA173879.pdf
A CANDU reactor can burn pure MOX fuel with 80 ish kg needed per year for a 900 megawatt sized unit to run 24/7/365 at that power level. When it’s fueled at year end 80% of that Pu is still there given the CR ratio in a heavy water reactor of 0.7-0.8 you need reprocessing to get at that though but with 8000 kg per year from a fusion fission hybrid you could once through 100 CANDU for every one fusion fission hybrid fuel factory it wouldn’t matter one bit of that hybrid every generated a single watt of net power the plutonium is the product not electrons. In fact you could run it at a energy loss of 660 megawatts if it’s a C0.3 buying that power would be a tiny opex vs the value of the energy 8000kg of Pu represents the EROI is in then
660 megawatt years vs
82,000 gigajoules per kg of Pu239 times 8000kg...
656,000,000 gigajoules
656,000,000 gigajoules is approximately equal to 7,592,592.6 megawatt-days.
Which is 20,801.62 megawatts years
That’s an EROI of 20801:1 <<<<this is how you run a civilization of 10+ billion at EU levels of energy consumption.
Again you can just buy the 660 megawatts from the grid you will make 20000+ the energy back via fisison of the produced plutonium.
Really 10000 given a 50% efficient fast reactor driving a supercritical CO2 turbine. Still 10000:1 EROI is spectacular.
“My Cuz is Nuclear certified and worked at the Palo Verde plant and then the Solar Plant at Ivanpah Nv until he retired. He always said many small ones rather than one big one is the way to go.”
Certified? How?
PVNGS proves that BIG works.
D-D catalyzed fusion fission hybrid breeder making 8,000 Kg of Pu 239 per year due to the use of a water breeding blanket also breeds deuterium along with tritium and the uranium salt in the water breeds the Pu. D-D produces He3 and Tritium in a 50/50 ratio of fusion products those fuse at lower temps vs D-D hence the catalyzed you feed everything back to your fusion monster it eats them all you want the high energy neutrons in this case it’s what your product is neutron capture in the breeding blanket makes 3 fuels not one you get single proton normal hydrogen to capture a neutron it then becomes deuterium your primary fuel, when deuterium also captures a neutron it becomes tritium your catalyst fuel and when U238 nitrite captures a neutron it becomes neptunium which beta decays shortly to plutonium.
This is an elegant way to turn deuterium and uranium into Pu with massive fission energy potential. Again you only need a S of 0.3 that’s three times energy into the fusion plasma vs energy out why? Because you are not trying to make electrons or what to drive a turbine you want every neutron you can make at the highest energy you can get them at. You can and should put a first wall not of beryllium you should use U238 why because 2+ MEV neutrons all cause fission in U238 and a 14MEV neutron from D-T fusion makes multiple U238 fission events before it falls below 2 MEV you can get 20-50x neutron multiplication rates for a U238 first wall fission blanket and it makes crazy heat you could easily have a Kef.98 as you breed up enough Pu in that blanket to make the whole hybrid system energy positives while still driving that water breeder blanket to now 8000+ Kg per year of Pu every additional neutron from that fission blanket is one more for breeding once it thermalizes in the water capture blanket.
We need to lose the fear of plutonium it’s that simple. Every nation that has wanted nukes has them and they sure as sh1t didn’t use civilian reactors to do it. They uses dedicated military type reactors either heavy waters or graphite moderated. A fusion fission hybrid breeder would make massive Pu but it wouldn’t be bomb grade there would be significant 240,241&242 in it due to subsequent neutron captures in the breed blanket it would be shitty bomb material but great fast spectrum reactor fuel and a heavy water reactor like a CANDU happily eats every Pu isotope too.
When worked the Seawolf in the early 80s as Nuclear Ship Superintendent in Mare Island, their first reactor - even by the crew - “wasn’t discussed much”.
The fast breeders and molten salt test reactors in the INEL were more promising.
Today? I would prefer to put 5x 500 Megawatt plants as ALL IDENTICAL units at one site. Shutdown and maintenance planning and operation proceeds sequentially around the star. One shutdown, 4 running.
One planning their next outage.
One engineering department.
One Radeon department.
One security team.
One fence.
One warehouse, one maintenance center.
One (large) transformer yard.
BUT!
Each is built sequentially. Using the same crew for each stage of construction. Same forms, same jigs, same cranesvand same training.
WWII ship construction - even of battleships and carriers- NOT just Liberty ships and destroyers! - shows sequentially construction by the same crews cuts costs, cuts schedule on each ship.
The last of 5 is only 68% the cost of the first.
Build them all at the same time?
Costs increase for each unit.
Each unit takes longer.
“Molten salts are interesting and their ability to retain heat either in the actual liquid “pile” (if I understand that correctly) or even the liquid salt “cooling system” could both run a steam turbine for an extended period of time.”
Most of the stored energy is latent heat and you don’t want the coolant to go solid.
I must defer to you on that...It seems exotic to me, but I almost grasp it.
Just curious, I was visualizing it that if either the core or coolant went solid, it would retain heat for some time after it. I know that in a nuclear reactor, you didn’t want it to go “solid” (in those fully liquid) because then you can have hydraulic hammer waves, which have no place to get absorbed...do I understand that correctly?
As you describe “going solid” in a molten coolant system, I assume that REALLY means “going solid”?
Interesting! So, you had real world experience with this? I think it is fascinating-it must have been beyond cutting edge in those days!
But the per-kwh price has skyrocketed on the SMR, to something like 16 cents, if I remember correctly. Hopefully, this just for the initial batch, and the price will start to decline.
I agree with you on the Plutonium. Sure, it is a dangerous substance, but I believe with proper technology and handling, the risk is outweighed by the benefit on the reaction side.
ACES Amigo!!
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