17 ms·

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 t

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-construction-hermes-reactor 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/ https://kairospower.com/technology/ [2] https://news.ycombinator.com/item?id=41841108 https://news.ycombinator.com/item?id=41841108

onepointsixC 2y ago
Yeah I’m not going to lie, that’s quite disappointing. Google funding several AP1000’s would be huge.
- iknowstuff 2y ago
  seeing how 2GW of nuclear cost $34B in Georgia, why would Google waste $120B when they can get the same output for at most half the price (and realistically more like 1/10th) using renewables and batteries? and they’d have results in 2 years instead of 2 decades. edit: to be clear, 1GW of wind or solar is $1B. Build 3GW for overcapacity and you’re still at just 17% of the cost of 1GW of nuclear, and you technically have 3x more capacity. Now figure out how many megapacks you can buy for the $14B/GW you saved https://www.tesla.com/megapack/design https://www.tesla.com/megapack/design (answer: 16GW/68GWh)
  - preisschild 2y ago
    Because they need power 24/7 and not only when the weather cooperates. And new AP1000s in the US would cost significantly less, because there are already experienced workers & supply chains from Vogtle and getting a license requires less work too, because you can copy much of Vogtle. The median build time for nuclear reactors is 7 years. This is archivable if you continue building and not just build 1 or 2 every few decades.
    - p1necone 2y ago
      > Because they need power 24/7 and not only when the weather cooperates. Hence the batteries.
      - rtkwe 2y ago
        The scale just isn't there. A single nuclear power plant near me, McGuire Nuclear Power Plant, produced 17,514 GW·h in 2005. The entire potential output of the Tesla (cough Panasonic) Gigafactories in California and China have a combined output of ~50 GWh per year. [0] Nuclear power is amazing at producing a reliable base load of power that massively outstrips our ability to produce and store solar power. Say our load is well aligned with the cycle of solar power and we're ignoring weather so we can derate the amount we want to store to 30% that's 105 years of production out of what I think is the two largest batter plants in existence to store the power produced continuously by a single large nuclear power plant. [0] https://www.fuld.com/tesla-energy-massive-growth-in-megapack-manufacturing/#:~:text=If%20we%20combine%20this%20with%20the%20potential%20output%20with%20Tesla%E2%80%99s%20new%20China%20plant%2C%20by%202025%20the%20combined%20output%20could%20be%20as%20high%20as%2050%20GW%20per%20year https://www.fuld.com/tesla-energy-massive-growth-in-megapack...
        toomuchtodo 2y ago
        Global stationary storage deployed for 2024 will be ~150GWh, and this is accelerating. Batteries are easy, nuclear appears to be impossible (economically speaking).
- treflop 2y ago
  I'm fairly pro-nuclear but the EIA (Energy Information Administration) publishes a "Levelized Costs of New Generation" report every year that compiles the total cost of installing new generation, taking into account the fuel, build up, maintenance, interest, and inflationary costs, and nuclear ends up costing more $$$ than other renewable alternatives. It's no conspiracy why nuclear never gets traction these days -- maybe it was cost-effective 10-30 years ago but renewable technology has gotten relatively cheap. (Shutting down active nuclear reactors earlier than needed is a whole different issue though.) Here's the report for 2023: https://www.eia.gov/outlooks/aeo/electricity_generation/pdf/AEO2023_LCOE_report.pdf https://www.eia.gov/outlooks/aeo/electricity_generation/pdf/... There is no report for 2024 because they are building a new model to take into account even newer technologies: https://www.eia.gov/pressroom/releases/press537.php https://www.eia.gov/pressroom/releases/press537.php
  - Moldoteck 2y ago
    https://liftoff.energy.gov/advanced-nuclear/ https://liftoff.energy.gov/advanced-nuclear/ https://www.sciencedirect.com/science/article/abs/pii/S0360544222018035 https://www.sciencedirect.com/science/article/abs/pii/S03605... Lazard report for lcoe is so funny because they assume 4h storage will be enough to cover the demand
- jeffbee 2y ago
  Google's entire thing only consumed on average 2.6x worth of AP1000 energy last year. Why does anyone think that the IT industry needs to pull all of the weight of electrifying the American economy by building 7 AP1000 power stations?
  - Tostino 2y ago
    They have the capital, and are the ones who need the extra generation capacity now. They will share the cost along with the average consumer as EVs take up a larger proportion of total vehicles on the road.
    - jeffbee 2y ago
      And you are applying this equally across all American industry? The production of chlorine by electrolysis consumes twice as much electricity in America than Google consumes worldwide. But I don't see you up here calling for Olin Chlor Alkali to build nuclear power stations, for some reason. Are you suggesting that the American chemical industry lacks capital?
  - throwaway2037 2y ago
    You raise a very good point. I need to do some research to understand your comment. 1) Google uses about 25 terawatt-hours per year. Source: https://www.statista.com/statistics/788540/energy-consumption-of-google/ https://www.statista.com/statistics/788540/energy-consumptio... 2) An AP100 nuclear reactor can produce up to 10 terawatt-hours per year. Source: https://canes.mit.edu/overnight-capital-cost-next-ap1000#:~:text=AP1000%20is%20now%20a%20proven,to%2080%20years%20and%20beyond https://canes.mit.edu/overnight-capital-cost-next-ap1000#:~:.... That is incredible to think just how much power that a single nuclear reactor can produce!
  - forgotoldacc 2y ago
    People say trillion dollar corporations need to start taking steps to limit climate change, then when they do, "Why should trillion dollar corporations need to pull their weight?" This top-down corporate order will make more change than Americans can individually.
- throwaway2037 2y ago
  Nuclear is a terrible investment in 2024. Price per delivered megawatt-hour is guaranteed to be much lower for a combination of solar+battery+wind. -- Edit -- To clarify, "Nuclear is a terrible investment for private industry in 2024." However, I understand why nation states (and their equivalents) would want a diversity of power sources. There many be non-economic reasons why nations want to build nuclear over solar+battery+wind.
  - forgotoldacc 2y ago
    There's something to be said for space. A nuclear reactor takes up far less land than an equivalent amount of wind and solar generation. That's quickly going to become a limiting factor in wind/solar rollout and already is in some smaller countries (unless they're willing to bulldoze their entire land to cover it in solar panels)
    - notTooFarGone 2y ago
      Ok we can all agree that the US has not a land problem. This argument is relevant in Europe but the US has more than enough space power transmission is a problem but it's solvable.
      - forgotoldacc 2y ago
        Just because the US has a lot of area doesn't mean it should all be paved over and turned into solar farms. "Who needs nature and green spaces? It could be cheap electricity instead" is a mindset the next generation will hate us for, just like our generation resents previous generations for thinking "Why not burn coal? It's cheap electricity and there's lots of air left." The US has a massive green space problem. It's a country of roads, parking lots, and corn fields and it's a problem that's visible from space. Don't take this as opposing solar energy. I support it versus fossil fuels. But if nuclear is viable, I'm for it.
    - throwaway2037 2y ago
      > There's something to be said for space. I see this argument a lot. Yes, the density is very high for nuclear power plants, but you need to build them in the middle of nowhere, for political and safety reasons. So, are we really saving space compared to solar? Plus, there is much less political resistance to solar farms, and almost zero safety issues (for PV). This comment: > unless they're willing to bulldoze their entire land to cover it in solar panels Your sentiment is interesting. No one says that when we talk about building new farms. Really, that is what people have done for the past 2000 years to alter our landscape. Can you imagine what Brazil looked like in 1800 vs today? Dramatic landscape changes due to farming. Same for US, Canada, New Zealand and Australia. California has plenty of desert or very unproductive land that can be covered with solar panels.
ViewTrick1002 2y ago
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-fake-customer-and-a-major-contract-in-peril-cast-doubt-on-nuscales-viability/ https://iceberg-research.com/2023/10/19/nuscale-power-smr-a-...
- credit_guy 2y ago
  > 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 https://en.wikipedia.org/wiki/Molten-Salt_Reactor_Experiment
lysace 2y ago
> 525 megawatts :( That's.. not very much. So typical of Google. Dip their toes in a new field. Get lots of press. Move on to the next thing.
photochemsyn 2y ago
This is all about the revival of pebble-bed reactors, which were attemped several decades ago but had problems with the graphite pebbles breaking down and releasing graphite fragments that clogged the pipes, basically. China is way ahead on this with helium-cooled versions. The big deal is that in the event of complete power loss (see Fukushima) they go into shutdown without melting down, although if the coolant lost and replaced with air you would get a nasty Chernobyl-style graphite fire. Still an improvement in safety. See: > "Several high-temperature thermal neutron–spectrum pebble bed reactors are being commercialized. China has started up two helium-cooled pebble bed high-temperature reactors. In the United States, the X-Energy helium-cooled and the Kairos Power salt-cooled pebble bed high-temperature reactors will produce spent nuclear fuel (SNF) with burnups exceeding 150 000 MWd per tonne. The reactor fuel in each case consists of small spherical graphite pebbles (4 to 6 cm in diameter) containing thousands of small TRISO (microspheric tri-structural isotropic) fuel particles embedded in the fuel of zone these pebbles." (2024) "Safeguards and Security for High-Burnup TRISO Pebble Bed Spent Fuel and Reactors" https://www.tandfonline.com/doi/full/10.1080/00295450.2023.2298157 https://www.tandfonline.com/doi/full/10.1080/00295450.2023.2... and https://www.powermag.com/nuclear-milestone-chinas-htr-pm-demonstrates-inherent-safety/ https://www.powermag.com/nuclear-milestone-chinas-htr-pm-dem...
- bb88 2y ago
  > although if the coolant lost and replaced with air you would get a nasty Chernobyl-style graphite fire Or alternatively, radioactive dust could be released into the atmosphere such as THTR-300 did. INL did a gap analysis in 2011 between what was known and what needed research. The german AVR reactor had technical issues that weren't expected -- dust being one of them. https://inldigitallibrary.inl.gov/sites/sti/sti/5026004.pdf https://inldigitallibrary.inl.gov/sites/sti/sti/5026004.pdf From what I can tell the dust issue is still a point of contention.
dang 2y ago
Ok, we've changed the title to language from the article itself (edited to fit HN's 80 char limit) which seems both representative and neutral. If there's a better title, we can change it again. (Submitted tile was "Google funding construction of seven U.S. nuclear reactors")
deleted 2y ago
[deleted]
petre 2y ago
> Kairos is in a pretty early stage. They started building a test reactor this summer, scheduled for completion by 2027 Sounds great in theory, but it took NuScale Power 6 years to get their design approved? I hope the AI hype lasts that long then maybe the world would have two certified 75 MWe SMR designs. Also the NuScale Idaho plant was cancelled last year when cost estimates balooned 3x. 9.3bn for a 460 MWe plant?
deleted 2y ago
[deleted]

onepointsixC 2y ago

Yeah I’m not going to lie, that’s quite disappointing. Google funding several AP1000’s would be huge.

iknowstuff 2y ago
seeing how 2GW of nuclear cost $34B in Georgia, why would Google waste $120B when they can get the same output for at most half the price (and realistically more like 1/10th) using renewables and batteries? and they’d have results in 2 years instead of 2 decades. edit: to be clear, 1GW of wind or solar is $1B. Build 3GW for overcapacity and you’re still at just 17% of the cost of 1GW of nuclear, and you technically have 3x more capacity. Now figure out how many megapacks you can buy for the $14B/GW you saved https://www.tesla.com/megapack/design https://www.tesla.com/megapack/design (answer: 16GW/68GWh)
- preisschild 2y ago
  Because they need power 24/7 and not only when the weather cooperates. And new AP1000s in the US would cost significantly less, because there are already experienced workers & supply chains from Vogtle and getting a license requires less work too, because you can copy much of Vogtle. The median build time for nuclear reactors is 7 years. This is archivable if you continue building and not just build 1 or 2 every few decades.
  - p1necone 2y ago
    > Because they need power 24/7 and not only when the weather cooperates. Hence the batteries.
    - rtkwe 2y ago
      The scale just isn't there. A single nuclear power plant near me, McGuire Nuclear Power Plant, produced 17,514 GW·h in 2005. The entire potential output of the Tesla (cough Panasonic) Gigafactories in California and China have a combined output of ~50 GWh per year. [0] Nuclear power is amazing at producing a reliable base load of power that massively outstrips our ability to produce and store solar power. Say our load is well aligned with the cycle of solar power and we're ignoring weather so we can derate the amount we want to store to 30% that's 105 years of production out of what I think is the two largest batter plants in existence to store the power produced continuously by a single large nuclear power plant. [0] https://www.fuld.com/tesla-energy-massive-growth-in-megapack-manufacturing/#:~:text=If%20we%20combine%20this%20with%20the%20potential%20output%20with%20Tesla%E2%80%99s%20new%20China%20plant%2C%20by%202025%20the%20combined%20output%20could%20be%20as%20high%20as%2050%20GW%20per%20year https://www.fuld.com/tesla-energy-massive-growth-in-megapack...
      - toomuchtodo 2y ago
        Global stationary storage deployed for 2024 will be ~150GWh, and this is accelerating. Batteries are easy, nuclear appears to be impossible (economically speaking).
treflop 2y ago
I'm fairly pro-nuclear but the EIA (Energy Information Administration) publishes a "Levelized Costs of New Generation" report every year that compiles the total cost of installing new generation, taking into account the fuel, build up, maintenance, interest, and inflationary costs, and nuclear ends up costing more $$$ than other renewable alternatives. It's no conspiracy why nuclear never gets traction these days -- maybe it was cost-effective 10-30 years ago but renewable technology has gotten relatively cheap. (Shutting down active nuclear reactors earlier than needed is a whole different issue though.) Here's the report for 2023: https://www.eia.gov/outlooks/aeo/electricity_generation/pdf/AEO2023_LCOE_report.pdf https://www.eia.gov/outlooks/aeo/electricity_generation/pdf/... There is no report for 2024 because they are building a new model to take into account even newer technologies: https://www.eia.gov/pressroom/releases/press537.php https://www.eia.gov/pressroom/releases/press537.php
- Moldoteck 2y ago
  https://liftoff.energy.gov/advanced-nuclear/ https://liftoff.energy.gov/advanced-nuclear/ https://www.sciencedirect.com/science/article/abs/pii/S0360544222018035 https://www.sciencedirect.com/science/article/abs/pii/S03605... Lazard report for lcoe is so funny because they assume 4h storage will be enough to cover the demand
jeffbee 2y ago
Google's entire thing only consumed on average 2.6x worth of AP1000 energy last year. Why does anyone think that the IT industry needs to pull all of the weight of electrifying the American economy by building 7 AP1000 power stations?
- Tostino 2y ago
  They have the capital, and are the ones who need the extra generation capacity now. They will share the cost along with the average consumer as EVs take up a larger proportion of total vehicles on the road.
  - jeffbee 2y ago
    And you are applying this equally across all American industry? The production of chlorine by electrolysis consumes twice as much electricity in America than Google consumes worldwide. But I don't see you up here calling for Olin Chlor Alkali to build nuclear power stations, for some reason. Are you suggesting that the American chemical industry lacks capital?
- throwaway2037 2y ago
  You raise a very good point. I need to do some research to understand your comment. 1) Google uses about 25 terawatt-hours per year. Source: https://www.statista.com/statistics/788540/energy-consumption-of-google/ https://www.statista.com/statistics/788540/energy-consumptio... 2) An AP100 nuclear reactor can produce up to 10 terawatt-hours per year. Source: https://canes.mit.edu/overnight-capital-cost-next-ap1000#:~:text=AP1000%20is%20now%20a%20proven,to%2080%20years%20and%20beyond https://canes.mit.edu/overnight-capital-cost-next-ap1000#:~:.... That is incredible to think just how much power that a single nuclear reactor can produce!
- forgotoldacc 2y ago
  People say trillion dollar corporations need to start taking steps to limit climate change, then when they do, "Why should trillion dollar corporations need to pull their weight?" This top-down corporate order will make more change than Americans can individually.
throwaway2037 2y ago
Nuclear is a terrible investment in 2024. Price per delivered megawatt-hour is guaranteed to be much lower for a combination of solar+battery+wind. -- Edit -- To clarify, "Nuclear is a terrible investment for private industry in 2024." However, I understand why nation states (and their equivalents) would want a diversity of power sources. There many be non-economic reasons why nations want to build nuclear over solar+battery+wind.
- forgotoldacc 2y ago
  There's something to be said for space. A nuclear reactor takes up far less land than an equivalent amount of wind and solar generation. That's quickly going to become a limiting factor in wind/solar rollout and already is in some smaller countries (unless they're willing to bulldoze their entire land to cover it in solar panels)
  - notTooFarGone 2y ago
    Ok we can all agree that the US has not a land problem. This argument is relevant in Europe but the US has more than enough space power transmission is a problem but it's solvable.
    - forgotoldacc 2y ago
      Just because the US has a lot of area doesn't mean it should all be paved over and turned into solar farms. "Who needs nature and green spaces? It could be cheap electricity instead" is a mindset the next generation will hate us for, just like our generation resents previous generations for thinking "Why not burn coal? It's cheap electricity and there's lots of air left." The US has a massive green space problem. It's a country of roads, parking lots, and corn fields and it's a problem that's visible from space. Don't take this as opposing solar energy. I support it versus fossil fuels. But if nuclear is viable, I'm for it.
  - throwaway2037 2y ago
    > There's something to be said for space. I see this argument a lot. Yes, the density is very high for nuclear power plants, but you need to build them in the middle of nowhere, for political and safety reasons. So, are we really saving space compared to solar? Plus, there is much less political resistance to solar farms, and almost zero safety issues (for PV). This comment: > unless they're willing to bulldoze their entire land to cover it in solar panels Your sentiment is interesting. No one says that when we talk about building new farms. Really, that is what people have done for the past 2000 years to alter our landscape. Can you imagine what Brazil looked like in 1800 vs today? Dramatic landscape changes due to farming. Same for US, Canada, New Zealand and Australia. California has plenty of desert or very unproductive land that can be covered with solar panels.

ViewTrick1002 2y ago

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-fake-customer-and-a-major-contract-in-peril-cast-doubt-on-nuscales-viability/ https://iceberg-research.com/2023/10/19/nuscale-power-smr-a-...

credit_guy 2y ago
> 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 https://en.wikipedia.org/wiki/Molten-Salt_Reactor_Experiment

lysace 2y ago

> 525 megawatts :( That's.. not very much. So typical of Google. Dip their toes in a new field. Get lots of press. Move on to the next thing.

photochemsyn 2y ago

This is all about the revival of pebble-bed reactors, which were attemped several decades ago but had problems with the graphite pebbles breaking down and releasing graphite fragments that clogged the pipes, basically. China is way ahead on this with helium-cooled versions. The big deal is that in the event of complete power loss (see Fukushima) they go into shutdown without melting down, although if the coolant lost and replaced with air you would get a nasty Chernobyl-style graphite fire. Still an improvement in safety. See: > "Several high-temperature thermal neutron–spectrum pebble bed reactors are being commercialized. China has started up two helium-cooled pebble bed high-temperature reactors. In the United States, the X-Energy helium-cooled and the Kairos Power salt-cooled pebble bed high-temperature reactors will produce spent nuclear fuel (SNF) with burnups exceeding 150 000 MWd per tonne. The reactor fuel in each case consists of small spherical graphite pebbles (4 to 6 cm in diameter) containing thousands of small TRISO (microspheric tri-structural isotropic) fuel particles embedded in the fuel of zone these pebbles." (2024) "Safeguards and Security for High-Burnup TRISO Pebble Bed Spent Fuel and Reactors" https://www.tandfonline.com/doi/full/10.1080/00295450.2023.2298157 https://www.tandfonline.com/doi/full/10.1080/00295450.2023.2... and https://www.powermag.com/nuclear-milestone-chinas-htr-pm-demonstrates-inherent-safety/ https://www.powermag.com/nuclear-milestone-chinas-htr-pm-dem...

bb88 2y ago
> although if the coolant lost and replaced with air you would get a nasty Chernobyl-style graphite fire Or alternatively, radioactive dust could be released into the atmosphere such as THTR-300 did. INL did a gap analysis in 2011 between what was known and what needed research. The german AVR reactor had technical issues that weren't expected -- dust being one of them. https://inldigitallibrary.inl.gov/sites/sti/sti/5026004.pdf https://inldigitallibrary.inl.gov/sites/sti/sti/5026004.pdf From what I can tell the dust issue is still a point of contention.

dang 2y ago

Ok, we've changed the title to language from the article itself (edited to fit HN's 80 char limit) which seems both representative and neutral. If there's a better title, we can change it again. (Submitted tile was "Google funding construction of seven U.S. nuclear reactors")

deleted 2y ago

[deleted]

petre 2y ago

> Kairos is in a pretty early stage. They started building a test reactor this summer, scheduled for completion by 2027 Sounds great in theory, but it took NuScale Power 6 years to get their design approved? I hope the AI hype lasts that long then maybe the world would have two certified 75 MWe SMR designs. Also the NuScale Idaho plant was cancelled last year when cost estimates balooned 3x. 9.3bn for a 460 MWe plant?

deleted 2y ago

[deleted]