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I firmly believe that iteration is the key to good engineering. SpaceX has got where they are (partly) due to running flight after flight with incremental impro

I firmly believe that iteration is the key to good engineering. SpaceX has got where they are (partly) due to running flight after flight with incremental improvements each time. The problem with the massive reactors is that you get to build only a couple of them, so you never get to take advantage of learnings to make the next one better/cheaper/quicker.

rob74 2y ago
So basically it's one economy of scale (making something bigger means the costs for safety, maintenance, personnel etc. are proportionally lower) vs. another economy of scale (making more of one thing decreases the costs per "unit"). Place your bets... About your comparison to SpaceX: the approach of building a rocket, launching it, letting it explode and then using the gathered data to make the next one explode later (or not at all) is fine for rockets, but I wouldn't want to see it applied to nuclear reactors.
- rkangel 2y ago
  I do agree on not letting nuclear reactors explode, but I did use the SpaceX example on purpose. Before SpaceX started to do it, the concept of iterating to that degree on rockets was unthinkable. There was a self reinforcing loop of "rocket launches are expensive, so we must plan for every contingency, so the launch cycle is long and expensive". SpaceX proved that wrong. I think small modular reactors are the way out of the similar cycle we've got for nuclear reactors. And I think that building a small number of large ones is going to be a lot better if we're also building a large number of small ones and learning. It's like not building a y houses for 30 years and then building a massive skyscraper. If that's all we do then we'll only ever have one way of building a skyscraper because there's no room to experiment on other construction materials and techniques.
  - pydry 2y ago
    >Before SpaceX started to do it, the concept of iterating to that degree on rockets was unthinkable. I'm pretty sure that was what NASA was going to do all the way back in the 70s before their funding got slashed. It was a novel idea but not a novel idea that SpaceX was particularly responsible for, just one they threw capital at because the government stopped caring after the space race. Nuclear power research, by contrast, never really suffered from a lack of available funds. They were throwing money at mini reactors back in the 90s, saying all the same stuff about how mass production would bring down the price.
    - pieix 2y ago
      NASA funding far exceeds SpaceX’s and always has. It shouldn’t take 4% of the US federal budget (NASA funding during Apollo) to run a hardware-rich design process!
      - pydry 2y ago
        Apollo was wound down because the government wanted NASA to focus on the space shuttle and all sorts of other things as well as slashing the total budget by a huge amount. So, while in theory it may have had the money, in practice it did not.
        pieix 2y ago
        The Shuttle cost $48 billion to develop in inflation-adjusted dollars — contrast this with the ~$5B spent on Starship development thus far. It’s hard to defend the claim that NASA is or ever has been under-funded.
        msandford 2y ago
        NASAs "do stuff" budget is super small because their "keep all the experts on staff" budget is insatiable. It's not entirely bad though, I'm sure lots of those folks are doing good and important stuff. But I don't think the balance between employment and building things is quite right. At least to my tastes.
operationcwal 2y ago
if you don't care about any externalities (like spacex), sure. but I doubt hospitals or just normal people who need electricity would be super happy about power sources failing because the people building them subscribed to the "move fast/break things" mentality instead of actually building reliable/safe infrastructure at the cost of it taking longer
- zaphar 2y ago
  Our energy infrastructure isn't particularly reliable right now. Power outages, while not at the level of a third world country, are quite frequent. Nuclear is the highest energy density power generation you can get. Investing in reactors that are less susceptible to explosions (Like a molten salt reactor) is an important step and it's really only viable if you can iterate which means building modular reactor. If you read the article you'll see that most of their iteration and experimentation is without the nuclear material. Something that is possible because the reactor itself is small and can be run through a bunch of safety checks without the dangerous parts. The route that Nuscale and Kairos are taking is both cheaper and safer than large scale reactors. And we are going to need something to fill the gaps when there is no wind or solar generation available if we want to get off fossil fuels.
  - ViewTrick1002 2y ago
    We have been attempting "small modular reactors" since the 1950s. They've never worked out. In the same sense that tiny coal plants never worked out. Large physical scale is everything with old school power generation technologies due to various scaling laws. https://spectrum.ieee.org/the-forgotten-history-of-small-nuclear-reactors https://spectrum.ieee.org/the-forgotten-history-of-small-nuc...
    - DennisP 2y ago
      We have plenty of small but commercially successful natural gas plants, so it doesn't seem to be a general principle. The only scaling law mentioned in your article is this: > a 400-MW reactor requires less than twice the quantity of concrete and steel to construct as a 200-MW reactor, and it can be operated with fewer than twice as many people. Writing in Science in 1961, a senior member of the AEC worried that “competition [from fossil fuel plants] is indeed formidable” and suggested that “with current pressurized-water reactor technology, lower nuclear power costs can be achieved most readily with large plants.” Almost all the SMRs we've built have been water cooled reactors, which require a large amount of concrete and steel. Newer designs, such as molten salt reactors, can use a lot less, because they operate near atmospheric pressure, don't have to leave room for a high-pressure pipe break introducing a large volume of steam, and have nothing that can cause a chemical explosion. They're also inherently stable and adaptive to load, with little need for active control. A small modular MSR could well work out.

rob74 2y ago

So basically it's one economy of scale (making something bigger means the costs for safety, maintenance, personnel etc. are proportionally lower) vs. another economy of scale (making more of one thing decreases the costs per "unit"). Place your bets... About your comparison to SpaceX: the approach of building a rocket, launching it, letting it explode and then using the gathered data to make the next one explode later (or not at all) is fine for rockets, but I wouldn't want to see it applied to nuclear reactors.

rkangel 2y ago
I do agree on not letting nuclear reactors explode, but I did use the SpaceX example on purpose. Before SpaceX started to do it, the concept of iterating to that degree on rockets was unthinkable. There was a self reinforcing loop of "rocket launches are expensive, so we must plan for every contingency, so the launch cycle is long and expensive". SpaceX proved that wrong. I think small modular reactors are the way out of the similar cycle we've got for nuclear reactors. And I think that building a small number of large ones is going to be a lot better if we're also building a large number of small ones and learning. It's like not building a y houses for 30 years and then building a massive skyscraper. If that's all we do then we'll only ever have one way of building a skyscraper because there's no room to experiment on other construction materials and techniques.
- pydry 2y ago
  >Before SpaceX started to do it, the concept of iterating to that degree on rockets was unthinkable. I'm pretty sure that was what NASA was going to do all the way back in the 70s before their funding got slashed. It was a novel idea but not a novel idea that SpaceX was particularly responsible for, just one they threw capital at because the government stopped caring after the space race. Nuclear power research, by contrast, never really suffered from a lack of available funds. They were throwing money at mini reactors back in the 90s, saying all the same stuff about how mass production would bring down the price.
  - pieix 2y ago
    NASA funding far exceeds SpaceX’s and always has. It shouldn’t take 4% of the US federal budget (NASA funding during Apollo) to run a hardware-rich design process!
    - pydry 2y ago
      Apollo was wound down because the government wanted NASA to focus on the space shuttle and all sorts of other things as well as slashing the total budget by a huge amount. So, while in theory it may have had the money, in practice it did not.
      - pieix 2y ago
        The Shuttle cost $48 billion to develop in inflation-adjusted dollars — contrast this with the ~$5B spent on Starship development thus far. It’s hard to defend the claim that NASA is or ever has been under-funded.
        msandford 2y ago
        NASAs "do stuff" budget is super small because their "keep all the experts on staff" budget is insatiable. It's not entirely bad though, I'm sure lots of those folks are doing good and important stuff. But I don't think the balance between employment and building things is quite right. At least to my tastes.

operationcwal 2y ago

if you don't care about any externalities (like spacex), sure. but I doubt hospitals or just normal people who need electricity would be super happy about power sources failing because the people building them subscribed to the "move fast/break things" mentality instead of actually building reliable/safe infrastructure at the cost of it taking longer

zaphar 2y ago
Our energy infrastructure isn't particularly reliable right now. Power outages, while not at the level of a third world country, are quite frequent. Nuclear is the highest energy density power generation you can get. Investing in reactors that are less susceptible to explosions (Like a molten salt reactor) is an important step and it's really only viable if you can iterate which means building modular reactor. If you read the article you'll see that most of their iteration and experimentation is without the nuclear material. Something that is possible because the reactor itself is small and can be run through a bunch of safety checks without the dangerous parts. The route that Nuscale and Kairos are taking is both cheaper and safer than large scale reactors. And we are going to need something to fill the gaps when there is no wind or solar generation available if we want to get off fossil fuels.
- ViewTrick1002 2y ago
  We have been attempting "small modular reactors" since the 1950s. They've never worked out. In the same sense that tiny coal plants never worked out. Large physical scale is everything with old school power generation technologies due to various scaling laws. https://spectrum.ieee.org/the-forgotten-history-of-small-nuclear-reactors https://spectrum.ieee.org/the-forgotten-history-of-small-nuc...
  - DennisP 2y ago
    We have plenty of small but commercially successful natural gas plants, so it doesn't seem to be a general principle. The only scaling law mentioned in your article is this: > a 400-MW reactor requires less than twice the quantity of concrete and steel to construct as a 200-MW reactor, and it can be operated with fewer than twice as many people. Writing in Science in 1961, a senior member of the AEC worried that “competition [from fossil fuel plants] is indeed formidable” and suggested that “with current pressurized-water reactor technology, lower nuclear power costs can be achieved most readily with large plants.” Almost all the SMRs we've built have been water cooled reactors, which require a large amount of concrete and steel. Newer designs, such as molten salt reactors, can use a lot less, because they operate near atmospheric pressure, don't have to leave room for a high-pressure pipe break introducing a large volume of steam, and have nothing that can cause a chemical explosion. They're also inherently stable and adaptive to load, with little need for active control. A small modular MSR could well work out.