5 ms·

First, as others have pointed out, Nukes can be throttled, they don't tend to be because its not economically efficient (basically the entire cost is front load

First, as others have pointed out, Nukes can be throttled, they don't tend to be because its not economically efficient (basically the entire cost is front loaded in the construction). But there is a _HUGE_ difference between simply not having the capacity because the wind isn't blowing, and having to predict 12-24 hours in advance what the energy load is going to be. In the latter case its entirely possible to spin a nuke or coal plant up in anticipation of the need. Plus, if you overbuilt nukes, and could guarantee a consistent energy overproduction then you could build all kinds of energy soaking plants, to say desalinate sea water, produce various liquid fuels, etc as well as drive the acceptance of electric cars with free night/weekend charging schedules. This is actually one of my issues with the Biden administrations "we need more charging" stations drive recently. Charging stations are a problem that will fix themselves when people can look at electric cars and actually say "i'm not driving a coal burner around" and its a no brainier to charge this thing vs buying gas. Until recently that calculation isn't clear, your playing around the edges with the numbers, and the best cases aren't even 2x. Continent wide off peak free and clean electricity for charging makes it obvious which is better. When that happens gas stations will scramble to install charging.

zdragnar 4y ago
There's a story making the rounds here about a family who is out $11k because they bought a used ford fusion. Within 6 months of buying it, the battery died. If they could buy a replacement battery, it would run them another $14k, but they can't even do that, because the batteries for the fusion aren't being made anymore. The dealer offered them $500 to take the car off their hands. I think the current median price for a new electric car is something like $67k. Buying used is a bit like taking the gamble of not having health insurance- maybe you'll be fine, maybe you'll get a life-wrecking bill.
- StillBored 4y ago
  That is ugly, at least in the US the car manufactures are under no obligation to provide parts beyond the warantee period, but they generally do, because its very profitable. That said, I tend to drive the wheels off my cars, but since my first, I've tended to buy very popular models, meaning that there is a nearly unlimited supply of junkyard parts. I would expect that is a partial solution to their problem. A wrecked car probably has a fine battery if it wasn't damaged in the wreck. That is the usual answer even with ICE cars because sh*t happens to them too, blown engine/transmission/whatever can easily exceed the purchase price/value of the car. OTOH, there are probably various borderline amoral ways to deal with the problem by shifting it somewhere else.
  - nathanaldensr 4y ago
    Except that engines and transmissions almost never cost as much to repair or even replace as batteries (which are getting more and more expensive over time as supply chain and materials shortages increase). They are also repairable by more people, including the actual vehicle owner.
    - StillBored 4y ago
      That is largely though because people aren't buying new engines/transmissions from the manufacture when they fail. Instead there is a robust remanufacturing industry which takes the old broken ones, and basically repairs them and sells them back through the auto parts supply chains. So, while its true a new battery pack costs a small fortune, most of them probably aren't completely useless when they fail. If car packs are anything like power tool packs, old laptop packs, and the like then they generally go "bad" when a cell or two get far enough out of spec that its not safe to charge/discharge them as a pack because the charge controllers aren't fine grained enough to manage each cell individually beyond monitoring. The internet are full of DYI projects where people collected packs with 18650 batteries, tore them out, quantified them, and then rebuilt them into packs with matching cells. I'm betting this holds true even for car packs not using a battery standard like the 18650s. Given a pile of back packs, they could be torn apart, the cells rematched, and then rebuilt into remanufactured packs. Sure they won't be 120% or whatever over their original capacity like the new ones, but a battery pack with 85% of its capacity sold for 1/8th of the price of a new one will likely have a market. BTW: Couple years ago when I was in yellowstone, Toyota had a big plaque on one of the visitor centers about how they were reusing prius batteries for solar backup. https://www.greencarreports.com/news/1098326_used-toyota-hybrid-batteries-repurposed-at-yellowstone-national-park https://www.greencarreports.com/news/1098326_used-toyota-hyb... So, even when they are at 50%/etc of their capacity they have a use in stationary applications.
  - zdragnar 4y ago
    I think it is a pretty bad sign when the cost of replacing a part is higher than the cost of the whole thing. I suspect this will continue to be true for any used EV whose MSRP (i.e. brand new price) is under $30k. If true, then EVs are the vehicle equivalent of single-use plastics.
cinntaile 4y ago
> But there is a _HUGE_ difference between simply not having the capacity because the wind isn't blowing, and having to predict 12-24 hours in advance what the energy load is going to be. In the latter case its entirely possible to spin a nuke or coal plant up in anticipation of the need. It seems like you think that no wind or wind comes as a complete surprise and that they don't use models to estimate the wind for the next day? How do you think the day-ahead prices are calculated? 1GW missing is 1GW missing, it doesn't matter if that's wind or nuclear. That mismatch needs to be accounted for.
- StillBored 4y ago
  The point isn't that they aren't modeling it, the point is when there is a shortfall, they can't just tell the wind to produce more, they have to find more traditional sources, and when those run out... well... calls for conservation and rolling blackouts when those fail. And they can and do, tell traditional plants they can't go down for maintenance, or that they have to come back online.
  - cinntaile 4y ago
    I don't get how this relates to my original point. Do you agree or disagree that both wind and nuclear need fossil fuel backups if there is no hydro that can fill in for the missing capacity?
    - StillBored 4y ago
      No, because I think nukes can be throttled and designed for load following, particularly on the timeframes required for grid supply.
      - cinntaile 4y ago
        Are you suggesting to run the current ones at lower than optimal output and only run at optimal output when necessary? That doesn't sound like a good use of capital.
merb 4y ago
btw... there is _HUGE_ difference between it is possible to do something in theory than in praxis, there is NO nuclear reactor that could scale in short periods of time. france which is _HUGE_ on nuclear still has at least ~7-12% of gas (depending if they can use solar and wind or not) and they still import power. so it's basically bullshit that it's just economically efficient, it's simple not possible, else it would've been done, but there are only load following plants and not more and there are still no small plants or fusion plants or some other stuff.
- StillBored 4y ago
  Its not theory, the US navy doesn't run gas backup plants on the subs/carriers. Their reactors follow the load, and its not an insignificant variation, since propulsion is on demand and in the case of a sub, likely the largest consumer.
  - merb 4y ago
    1. they use diesel generators as backup (they need to and it's a safety net) 2. they follow the load but they also pump out unnecessary energy (heat) into the ocean (you can't do that with normal reactors, BECAUSE you don't have infinite cooling water) 3. it's way smaller and the load is way smaller < 100 MW which of course makes load following way way more easier
    - StillBored 4y ago
      Emergency use != load following. The fact that sometimes energy needs to be dumped != system cannot be throttled. And a huge number of nuke plants are already on the coast so, they have just as much water as a sub (not that this really matters). And I suspect size isn't really a factor here, its more about time variance, which I suspect is higher on a ship than its is on the grid. The grid wouldn't be swinging its power usage as drastically or completely as one would expect from propulsion onboard a ship. This is more about whether its possible to run the reactor at say 50% rated capacity for long periods of time, which AFAIK naval reactors can do, and to a certain extent so can some civilian plants, rod placement controls not just criticality but in the end heat generation, which translates to power output.

zdragnar 4y ago

There's a story making the rounds here about a family who is out $11k because they bought a used ford fusion. Within 6 months of buying it, the battery died. If they could buy a replacement battery, it would run them another $14k, but they can't even do that, because the batteries for the fusion aren't being made anymore. The dealer offered them $500 to take the car off their hands. I think the current median price for a new electric car is something like $67k. Buying used is a bit like taking the gamble of not having health insurance- maybe you'll be fine, maybe you'll get a life-wrecking bill.

StillBored 4y ago
That is ugly, at least in the US the car manufactures are under no obligation to provide parts beyond the warantee period, but they generally do, because its very profitable. That said, I tend to drive the wheels off my cars, but since my first, I've tended to buy very popular models, meaning that there is a nearly unlimited supply of junkyard parts. I would expect that is a partial solution to their problem. A wrecked car probably has a fine battery if it wasn't damaged in the wreck. That is the usual answer even with ICE cars because sh*t happens to them too, blown engine/transmission/whatever can easily exceed the purchase price/value of the car. OTOH, there are probably various borderline amoral ways to deal with the problem by shifting it somewhere else.
- nathanaldensr 4y ago
  Except that engines and transmissions almost never cost as much to repair or even replace as batteries (which are getting more and more expensive over time as supply chain and materials shortages increase). They are also repairable by more people, including the actual vehicle owner.
  - StillBored 4y ago
    That is largely though because people aren't buying new engines/transmissions from the manufacture when they fail. Instead there is a robust remanufacturing industry which takes the old broken ones, and basically repairs them and sells them back through the auto parts supply chains. So, while its true a new battery pack costs a small fortune, most of them probably aren't completely useless when they fail. If car packs are anything like power tool packs, old laptop packs, and the like then they generally go "bad" when a cell or two get far enough out of spec that its not safe to charge/discharge them as a pack because the charge controllers aren't fine grained enough to manage each cell individually beyond monitoring. The internet are full of DYI projects where people collected packs with 18650 batteries, tore them out, quantified them, and then rebuilt them into packs with matching cells. I'm betting this holds true even for car packs not using a battery standard like the 18650s. Given a pile of back packs, they could be torn apart, the cells rematched, and then rebuilt into remanufactured packs. Sure they won't be 120% or whatever over their original capacity like the new ones, but a battery pack with 85% of its capacity sold for 1/8th of the price of a new one will likely have a market. BTW: Couple years ago when I was in yellowstone, Toyota had a big plaque on one of the visitor centers about how they were reusing prius batteries for solar backup. https://www.greencarreports.com/news/1098326_used-toyota-hybrid-batteries-repurposed-at-yellowstone-national-park https://www.greencarreports.com/news/1098326_used-toyota-hyb... So, even when they are at 50%/etc of their capacity they have a use in stationary applications.
- zdragnar 4y ago
  I think it is a pretty bad sign when the cost of replacing a part is higher than the cost of the whole thing. I suspect this will continue to be true for any used EV whose MSRP (i.e. brand new price) is under $30k. If true, then EVs are the vehicle equivalent of single-use plastics.

cinntaile 4y ago

> But there is a _HUGE_ difference between simply not having the capacity because the wind isn't blowing, and having to predict 12-24 hours in advance what the energy load is going to be. In the latter case its entirely possible to spin a nuke or coal plant up in anticipation of the need. It seems like you think that no wind or wind comes as a complete surprise and that they don't use models to estimate the wind for the next day? How do you think the day-ahead prices are calculated? 1GW missing is 1GW missing, it doesn't matter if that's wind or nuclear. That mismatch needs to be accounted for.

StillBored 4y ago
The point isn't that they aren't modeling it, the point is when there is a shortfall, they can't just tell the wind to produce more, they have to find more traditional sources, and when those run out... well... calls for conservation and rolling blackouts when those fail. And they can and do, tell traditional plants they can't go down for maintenance, or that they have to come back online.
- cinntaile 4y ago
  I don't get how this relates to my original point. Do you agree or disagree that both wind and nuclear need fossil fuel backups if there is no hydro that can fill in for the missing capacity?
  - StillBored 4y ago
    No, because I think nukes can be throttled and designed for load following, particularly on the timeframes required for grid supply.
    - cinntaile 4y ago
      Are you suggesting to run the current ones at lower than optimal output and only run at optimal output when necessary? That doesn't sound like a good use of capital.

merb 4y ago

btw... there is _HUGE_ difference between it is possible to do something in theory than in praxis, there is NO nuclear reactor that could scale in short periods of time. france which is _HUGE_ on nuclear still has at least ~7-12% of gas (depending if they can use solar and wind or not) and they still import power. so it's basically bullshit that it's just economically efficient, it's simple not possible, else it would've been done, but there are only load following plants and not more and there are still no small plants or fusion plants or some other stuff.

StillBored 4y ago
Its not theory, the US navy doesn't run gas backup plants on the subs/carriers. Their reactors follow the load, and its not an insignificant variation, since propulsion is on demand and in the case of a sub, likely the largest consumer.
- merb 4y ago
  1. they use diesel generators as backup (they need to and it's a safety net) 2. they follow the load but they also pump out unnecessary energy (heat) into the ocean (you can't do that with normal reactors, BECAUSE you don't have infinite cooling water) 3. it's way smaller and the load is way smaller < 100 MW which of course makes load following way way more easier
  - StillBored 4y ago
    Emergency use != load following. The fact that sometimes energy needs to be dumped != system cannot be throttled. And a huge number of nuke plants are already on the coast so, they have just as much water as a sub (not that this really matters). And I suspect size isn't really a factor here, its more about time variance, which I suspect is higher on a ship than its is on the grid. The grid wouldn't be swinging its power usage as drastically or completely as one would expect from propulsion onboard a ship. This is more about whether its possible to run the reactor at say 50% rated capacity for long periods of time, which AFAIK naval reactors can do, and to a certain extent so can some civilian plants, rod placement controls not just criticality but in the end heat generation, which translates to power output.