Most active commenters
  • Manuel_D(7)
  • philwelch(4)
  • ViewTrick1002(4)
  • bobthepanda(3)
  • adrianN(3)
  • Dylan16807(3)

←back to thread

589 points atomic128 | 27 comments | | HN request time: 0.002s | source | bottom
Show context
philipkglass ◴[] No.41841019[source]
Based on the headline I thought that this was an enormous capital commitment for an enormous generating capacity, but the deal is with a company called Kairos that is developing small modular reactors with 75 megawatts of electrical output each [1]. 7 reactors of this type, collectively, would supply 525 megawatts (less than half of a typical new commercial power reactor like the AP1000, HPR1000, EPR, or APR1400).

Kairos is in a pretty early stage. They started building a test reactor this summer, scheduled for completion by 2027:

https://www.energy.gov/ne/articles/kairos-power-starts-const...

EDIT: Statement from the official Google announcement linked by xnx below [2]:

Today, we’re building on these efforts by signing the world’s first corporate agreement to purchase nuclear energy from multiple small modular reactors (SMRs) to be developed by Kairos Power. The initial phase of work is intended to bring Kairos Power’s first SMR online quickly and safely by 2030, followed by additional reactor deployments through 2035. Overall, this deal will enable up to 500 MW of new 24/7 carbon-free power to U.S. electricity grids and help more communities benefit from clean and affordable nuclear power.

[1] https://kairospower.com/technology/

[2] https://news.ycombinator.com/item?id=41841108

replies(8): >>41841055 #>>41842094 #>>41842395 #>>41843875 #>>41844253 #>>41845537 #>>41845613 #>>41848283 #
ViewTrick1002 ◴[] No.41842094[source]
Would be extremely interesting to the the $/MWh for the deal to understand the viability.

Otherwise similar to the NuScale deal which fell through last autumn.

A PPA like agreement which then only kept rising until all potential utilities had quit the deal.

All honor to Kairos if they can deliver, but history is against them. Let’s hope they succeed.

> NuScale has a more credible contract with the Carbon Free Power Project (“CFPP”) for the Utah Associated Municipal Power Systems (“UAMPS”). CFPP participants have been supportive of the project despite contracted energy prices that never seem to stop rising, from $55/MWh in 2016, to $89/MWh at the start of this year. What many have missed is that NuScale has been given till around January 2024 to raise project commitments to 80% or 370 MWe, from the existing 26% or 120 MWe, or risk termination. Crucially, when the participants agreed to this timeline, they were assured refunds for project costs if it were terminated, which creates an incentive for them to drop out. We are three months to the deadline and subscriptions have not moved an inch.

https://iceberg-research.com/2023/10/19/nuscale-power-smr-a-...

replies(2): >>41842380 #>>41846359 #
credit_guy ◴[] No.41842380[source]
> All honor to Kairos if they can deliver, but history is against them.

History is not really against them. Our current reactors (mainly pressurized water reactors) are the way they are because Admiral Rickover determined that PWRs are the best option for submarines. He was not wrong, but civilian power reactors are not the same as the reactors powering submarines.

PWRs are expensive mainly because of the huge pressure inside the reactor core, about 150 times higher than the atmospheric pressure. For comparison, a pressure cooker has an internal pressure about 5 times higher than the atmospheric pressure, and such a cooker can explode with a pretty loud bang.

The Kairos Hermes reactor design is based on a design that was tested in the '60s, the Molten-Salt Reactor Experiment [1]. While such a reactor can be used to burn thorium, Kairos decided to go with the far more conventional approach of burning U-235. The reactor operates at approximately regular atmospheric pressure. This should reduce considerably the construction costs.

Of course, there are unknowns. While the world has built thousands of pressurized water reactors, it has built maybe 10 molten salt reactors. For example one quite unexpected effect in the MSRE was the enbrittlement of the reactor vessel caused by tellurium, which shows up as a fission product when U-235 burns.

The Nuclear Regulatory Commission is a very conservative organization, and they don't have much experience with molten salt reactors because nobody has. It took them 6 years to give NuScale an approval for a pressurized water reactor, design that they knew in and out. My guess is that they will not give Kairos an approval without at least 15 years of testing. But Google's agreement with Kairos is quite crucial to keep this testing going.

[1] https://en.wikipedia.org/wiki/Molten-Salt_Reactor_Experiment

replies(6): >>41843113 #>>41843300 #>>41843515 #>>41844374 #>>41846610 #>>41847860 #
cyberax ◴[] No.41843113[source]
> The Kairos Hermes reactor design is based on a design that was tested in the '60s, the Molten-Salt Reactor Experiment

MSRs are a costly distraction. They are not viable without literally hundreds of billions in research and development money. That's why all the MSRs startups are failing long before they even start the licensing process.

> For example one quite unexpected effect in the MSRE was the enbrittlement of the reactor vessel caused by tellurium, which shows up as a fission product when U-235 burns.

It was not unexpected. The _main_ issue with MSRs is that they have to contain fluoride salts that release elemental fluorine radicals as a result of radiolysis. So the reactor vessel walls will be eaten up by them, rather rapidly. Especially when reactors are scaled up to a level that makes them practical. And then you have all the fission byproducts that literally include almost all the Periodic Table.

replies(2): >>41844000 #>>41844329 #
Dylan16807 ◴[] No.41844329[source]
> They are not viable without literally hundreds of billions in research and development money.

The US produces 40000 billion kWh every decade, so that doesn't really seem that bad to me.

replies(2): >>41844399 #>>41844557 #
oblio ◴[] No.41844399{3}[source]
When solar and wind and sodium ion batteries are basically there and probably don't need as much investment and R&D (or it's happening anyway from 1000 existing funding sources), it's probably bad. Or at least unlikely to happen.
replies(3): >>41844618 #>>41845607 #>>41845643 #
Manuel_D ◴[] No.41845607{4}[source]
Intermittency is a tough thing to handle. The US uses 12,000 GWh of electricity per day. The word used 60,000 GWh per day. Evening out daily fluctuations, let alone seasonal fluctuations, demands an enormous amount of storage.
replies(2): >>41846988 #>>41847026 #
1. nosbo ◴[] No.41846988{5}[source]
Or just overbuild your generation sources?
replies(2): >>41849014 #>>41850164 #
2. TheCraiggers ◴[] No.41849014[source]
How is overbuilding going to help when the source of the power itself is intermittent? The sun regularly sets and the wind has this unfortunate habit of not blowing. Or, oddly enough, blowing too much.

If we hope to go 100% renewable, storage is a key piece of that puzzle.

replies(3): >>41849541 #>>41850055 #>>41851990 #
3. snapplebobapple ◴[] No.41849541[source]
It wont help much but it was the actul solution when the main source of electricity was fossil fuels because you could stockpile the fossil fuel
4. bobthepanda ◴[] No.41850055[source]
Nuclear also has this problem because it cannot be easily tuned down during low demand periods.

Much of the pumped hydro that exists today was built to handle excess nuclear.

replies(3): >>41850193 #>>41850215 #>>41850449 #
5. Manuel_D ◴[] No.41850164[source]
Overbuilding doesn't make solar generate power at night. Days with minimal wind can see 10% average wind speeds or less.
6. Manuel_D ◴[] No.41850193{3}[source]
Nuclear's electrical output can indeed be turned down, by over-cooling the steam in the turbines. The reactor is putting out the same power, but less electricity is generated since you're deliberately increasing waste heat. This is not efficient so it's rarely done.

Furthermore, too much energy is a far easier problem to solve than too little energy. People can desalinate water, or do any other energy intensive things.

replies(1): >>41850828 #
7. cyberax ◴[] No.41850215{3}[source]
Nuclear can handle variable loads just fine, if reactors are designed with load-following in mind. France does that, for example.
replies(2): >>41850818 #>>41850920 #
8. philwelch ◴[] No.41850449{3}[source]
“Oh no we have too much power, what are we going to do with it” is a much better problem to have than “the sun and wind are going down at the same time and we don’t have enough power, what are we going to do about it”.
replies(1): >>41850825 #
9. ViewTrick1002 ◴[] No.41850818{4}[source]
Technically yes if you have an entire fleet to both spread the load following across and their manage their fuel cycles since they get less flexible the further into a fuel cycle a reactor is.

Economically? Load following with nuclear power means an even worse business case than running at 100% 24/7. And nuclear power is already a laughably bad business case when running at 100%.

replies(1): >>41850861 #
10. ViewTrick1002 ◴[] No.41850825{4}[source]
It means the nuclear power plants shut down and then start losing money hand over fist, eventually closing.
replies(1): >>41850975 #
11. ViewTrick1002 ◴[] No.41850828{4}[source]
Technically yes if you have an entire fleet to both spread the load following across and their manage their fuel cycles since they get less flexible the further into a fuel cycle a reactor is.

Economically? Load following with nuclear power means an even worse business case than running at 100% 24/7. And nuclear power is already a laughably bad business case when running at 100%.

replies(1): >>41850931 #
12. Manuel_D ◴[] No.41850861{5}[source]
You don't need to change fuel cycles to reduce the output of a nuclear plant. You can accomplish it by more aggressively cooling the water in the steam turbines, effectively wasting heat (and thus generating less power).

Nuclear is a bad business case compared to a fossil fuel grid. Solar and wind backed by fossil fuels are a better business choice, too. But when it comes to a fossil-fuel free grid, it's the only viable option if you don't have a big source of hydropower nearby. Batteries can't deliver the required storage capacity. Remember, the world uses 60,000 GWh of electricity per day. And as transportation and industrial uses of fossil fuels are electrified, that'll increase.

replies(1): >>41855325 #
13. bobthepanda ◴[] No.41850920{4}[source]
Notably it also runs the reactors much harder, which has led to situations like France needing to shut all nuclear plants at once for maintenance.
14. Manuel_D ◴[] No.41850931{5}[source]
The fuel is burned at the same rate using this method of modulating output. Thermal output from the reactor is the same. Electrical output is reduced because heat is deliberately wasted.
15. philwelch ◴[] No.41850975{5}[source]
Don’t piss on my leg and tell me it’s raining. Most of the costs and all of the shutdowns in nuclear power are primarily motivated by anti-nuclear activism. What you’re describing is a policy choice, not an essential reality.
replies(1): >>41852371 #
16. energy123 ◴[] No.41851990[source]
Simulation studies have covered this. It addresses it by providing more power when there is less sunlight and less wind.
17. bobthepanda ◴[] No.41852371{6}[source]
If it costs you money to generate power at a time you cannot sell it, that is losing money. Wind and solar are unique in that they have low marginal costs, whereas a nuclear plant requires more staffing and fuel burn.
replies(2): >>41852587 #>>41855357 #
18. TheCraiggers ◴[] No.41852587{7}[source]
I don't understand why you're coming about this problem from a "100% nuclear" situation. That's not the case for the world, and likely never will be the case. But heck, let's assume all you've got to work with is nuclear.

You have a baseload. That's basically the minimum load that always exists. You don't have to worry about selling the power, it's already sold. And then you have peak. Both of these are time / weather dependent but we're still quite able to plan days, if not weeks and months, in advance for what those two values will be. As an example, let's get back to the original topic of the article.

If you're Google and you have a particular datacenter at a location, you know what that baseload is. You know what the peak is. It's a pretty simple calculation to figure out what is most cost-effective here. It's probably even easier for you than the local power company, as base and peak loads likely don't fluctuate much for you outside of HVAC keeping up with weather. It might be to use nuclear for just base load and use the local grid for the rest. It might be to over-produce occasionally because that's still cheaper than buying from the local system operator. Hell, you can probably sell any access, but that's more of a problem than most people think.

But the point is nuclear is king when it comes to baseload power supply. And a datacenter, which consumes a lot of power consistently, is almost entirely baseload.

replies(1): >>41855064 #
19. philwelch ◴[] No.41855064{8}[source]
Also, if you're serious about the problem of "our nuclear power plants are producing more power than we need and we can't turn them off because then we'll have a power shortage", there are applications to dump "bonus" energy into. You'd run into the same problem with renewables too; the difference is that with nuclear, you can avoid the "not enough energy" problem.
20. adrianN ◴[] No.41855325{6}[source]
Batteries and hydro are not the only storage options.
replies(1): >>41860385 #
21. Dylan16807 ◴[] No.41855357{7}[source]
If you're not in Texas, there's such a thing as paying to keep capacity available, and then you don't lose money.

And power plants having individual finances in the first place is a policy choice, not a law of nature.

replies(1): >>41861359 #
22. Manuel_D ◴[] No.41860385{7}[source]
What are the other storage options? Besides batteries and hydroelectric, there's only prototype technologies that haven't seen any significant deployment at scale. Compressed air, hydrogen, and power to gas have been tried but no at anywhere near grid scales.
replies(1): >>41861405 #
23. philwelch ◴[] No.41861359{8}[source]
We have a version of that in Texas, too. There are some commercial cryptocurrency mining operations that pay for a certain level of power capacity, and if the grid is running low on power, the grid just buys the capacity back from them and they stop mining for awhile.

If you find cryptocurrency mining objectionable for some reason, you could apply the same basic principle to things like aluminum refining or desalination.

replies(1): >>41875005 #
24. adrianN ◴[] No.41861405{8}[source]
Five years ago batteries weren’t anywhere near grid scale either. Arguably they still aren’t. That doesn’t mean we should not consider them when talking snot the grid in 2040.
replies(1): >>41861490 #
25. Manuel_D ◴[] No.41861490{9}[source]
Sure. But we also shouldn't assume they will be successful at grid-scale either. Planning a grid assuming that some future storage technology will be a silver bullet that solves grid storage is a massive gamble.

Hydroelectric storage is the only grid-scale energy storage system available to us, and it's geographically dependent. And the places that are suitable for hydroelectric storage usually don't need it because they can just generate electricity via hydropower anyway. Until your hypothetical breakthrough in power-to-gas or giant flywheels actually happens, this is the state of grid storage.

replies(1): >>41861990 #
26. adrianN ◴[] No.41861990{10}[source]
It's not such a massive gamble if you can just keep relying on natural gas peaker plants in case storage is somehow unsolvable, which seems quite unlikely given that we have a dozen completely different technologies for storage in the pipeline.
27. Dylan16807 ◴[] No.41875005{9}[source]
That's still only paying when the capacity is needed. It doesn't do a good job of incentivizing power sources/releases that are needed very rarely.