9 ms·

Can we stop with these convoluted systems and just do nuclear already?

by um_ya 6y ago

X6S1x6Okd1st 6y ago
With nuclear you still need storage to flatten the peaks and troughs though right? Also this does not seem very convoluted, it's using an electric engine pretty directly. If you are actually boring straight down it seems like the failure modes are pretty okay.
- core-questions 6y ago
  > With nuclear you still need storage to flatten the peaks and troughs though right? Why? Just build more. Keep expanding capacity so the base load covers the peaks and thensome. Push the price of electricity down while keeping it carbon-neutral and crush competition. Get everyone 2c/kwh power. Wouldn't that be more fun?
  - _ph_ 6y ago
    The problem is the speed at which the reactors can be ramped up and down, this is very limited. Also, if you have enough capacity to cover all peaks, most of the time the reactors are not running at full power. That increases the cost of operating the reactors, which is far higher than you claim. Currently, projects building new nuclear reactors are challenged by their costs. Never mention the safety concerns and of course the waste problem.
    - core-questions 6y ago
      So print more money, what does it even matter anymore in the land of MMT? > the waste problem. Ehh, it's well managed in Canada and France, I don't see why Americans can't handle it. Just keep it away from fault lines, right? I bet some of those old missile silos would be perfect.
      - _ph_ 6y ago
        You would only have to print half as much money, if you use solar+wind+storage. And please enlighten me, how does France manage their nuclear waste problem?
        p_l 6y ago
        Like every sane country, they reuse it - only the final, hard-to-use fractions are stored, which takes a relatively small hall (pretty sure typical US football stadium is bigger). And those hard-to-use fractions aren't going to be a problem for long, pretty sure they are considerably shorter-time risk than the timeframe for cleanup of WW1 battlefields in France (which currently stands at around 700 years).
    - jabl 6y ago
      Current versions of the traditional LWR design can ramp at about 5% of full power per minute, which is about the same ramping rate as a CCGT plant. With steam bypass it's possible to ramp even faster. Demand response, frequently promoted as a way to increase penetration of intermittent renewables, can also be used to reduce the cost of a system composed on high capital cost, low marginal cost dispatchable generators like nuclear. Charge the EV's and run heat pumps to warm thermal storages during the night when demand is lower, say.
      - _ph_ 6y ago
        Yes, demand response will play a huge role in the grids of the future. But when you say "current versions", which current operating nuclear plant achieves this ramp speed? Also, it means you have to run your reactors regularly at below 100%, so you still can react on additional demand, which increases further the cost of a very expensive technology.
        jabl 6y ago
        > But when you say "current versions", which current operating nuclear plant achieves this ramp speed? IIRC that 5% figure I read was wrt EPR and AP1000, presumably older generation LWR's are slower, by how much I'm not sure. France has run older generation PWR's in load-following mode for decades, but I'm not sure which ramp speeds they achieve; fast enough in practice in any case it seems. CANDU reactors in Canada have steam bypass and can apparently ramp at >10%/min. In any case, my point is that ramp speed is in practice not a technical limitation. Of course you want to run a generator with high capital cost but very low marginal cost at 100% as much as possible, but if you now and then need to ramp (say, if the wholesale price goes negative) you can do it. > Also, it means you have to run your reactors regularly at below 100%, so you still can react on additional demand, which increases further the cost of a very expensive technology. To be clear, I'm not advocating a 100% nuclear grid. I'm just pointing out that the "nuclear can't ramp and is thus unsuited for the grid of the future" isn't correct. In particular, I think solar and a moderate amount of storage is very well suited to cover the daily variation in many parts of the world. I also think that dispatchable low-carbon sources (which could be hydro, or nuclear, or something else like geothermal where available, CCS where geological formations for storing CO2 are available, etc.) have a role to play in least-cost deep decarbonized grids. See e.g. https://doi.org/10.1016/j.joule.2018.08.006 https://doi.org/10.1016/j.joule.2018.08.006
    - p_l 6y ago
      A lot of the costs is politics, and second-order effects from lack of production lines making everything a one-off. Which "funnily" enough makes it so that the more dangerous reactors remain in use for longer, as the new designs aren't built, despite huge safety improvements (even if you go just for late 1970's self-sealing molten lead/bismuth reactors). Overcapacity is a problem, especially for low-enriched reactors, but that's why it shouldn't be the only answer.
  - imtringued 6y ago
    Are you joking? Building nuclear power to cover peaks is insanely uneconomical. More expensive than building a nuclear power plant in a flexible grid. If you don't know anything about how a grid functions then maybe you should stop shoehorning a single solution to solve every problem when everyone is already aware that a large array of different technologies is necessary for a modern grid.
  - p_l 6y ago
    If you have more production than demand you need to store it somewhere, which is exactly the point of such projects, if only to prevent network desynchronisation that causes brown/blackouts due to power flowing in different way than you want in the grid. Energy storage has also been planned for nuclear power plants as starter and emergency power.
rsync 6y ago
You'd compare the relative simplicity and complexity of a nuclear reactor to this "dig a hole in the ground and drop a weight" scheme ? Regardless of your thoughts on Nuclear, this is clearly a much simpler device. Also, I suspect the failure modes in this are pretty boring ...
reegnz 6y ago
Exactly. Most people just don't want to accept the fact that when it comes to energy density, nothing compares to nuclear. Nothing even comes close. https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/
- dave333 6y ago
  even if nuclear had no contamination horrors, this is no longer true. Hydrino energy is much more energy dense and will be the ubiquitous portable power source for the 21st century and beyond. https://brilliantlightpower.com/news/ https://brilliantlightpower.com/news/
  - reegnz 6y ago
    My comment might be read as 'Nothing will EVER compare to nuclear'. While in fact what I meant was 'CURRENTLY nothing scientifically viable compares to nuclear.' I do have high hopes about fusion and molten salt thorium is also up there as something I'd like to be further explored. But currently nothing up and coming seems to compare to nuclear. I just did a quick skim of the wikipedia page of that 'hydrino' stuff: https://en.wikipedia.org/wiki/Brilliant_Light_Power#Criticism https://en.wikipedia.org/wiki/Brilliant_Light_Power#Criticis.... I'm not an expert, but reading those criticisms makes me think this is nothing more than a money grab scheme without delivering anything usable for the past 30 years. Also, this thread: https://news.ycombinator.com/item?id=24423103 https://news.ycombinator.com/item?id=24423103

Can we stop with these convoluted systems and just do nuclear already?

by um_ya 6y ago

Can we stop with these convoluted systems and just do nuclear already?

With nuclear you still need storage to flatten the peaks and troughs though right? Also this does not seem very convoluted, it's using an electric engine pretty directly. If you are actually boring straight down it seems like the failure modes are pretty okay.

core-questions 6y ago
> With nuclear you still need storage to flatten the peaks and troughs though right? Why? Just build more. Keep expanding capacity so the base load covers the peaks and thensome. Push the price of electricity down while keeping it carbon-neutral and crush competition. Get everyone 2c/kwh power. Wouldn't that be more fun?
- _ph_ 6y ago
  The problem is the speed at which the reactors can be ramped up and down, this is very limited. Also, if you have enough capacity to cover all peaks, most of the time the reactors are not running at full power. That increases the cost of operating the reactors, which is far higher than you claim. Currently, projects building new nuclear reactors are challenged by their costs. Never mention the safety concerns and of course the waste problem.
  - core-questions 6y ago
    So print more money, what does it even matter anymore in the land of MMT? > the waste problem. Ehh, it's well managed in Canada and France, I don't see why Americans can't handle it. Just keep it away from fault lines, right? I bet some of those old missile silos would be perfect.
    - _ph_ 6y ago
      You would only have to print half as much money, if you use solar+wind+storage. And please enlighten me, how does France manage their nuclear waste problem?
      - p_l 6y ago
        Like every sane country, they reuse it - only the final, hard-to-use fractions are stored, which takes a relatively small hall (pretty sure typical US football stadium is bigger). And those hard-to-use fractions aren't going to be a problem for long, pretty sure they are considerably shorter-time risk than the timeframe for cleanup of WW1 battlefields in France (which currently stands at around 700 years).
  - jabl 6y ago
    Current versions of the traditional LWR design can ramp at about 5% of full power per minute, which is about the same ramping rate as a CCGT plant. With steam bypass it's possible to ramp even faster. Demand response, frequently promoted as a way to increase penetration of intermittent renewables, can also be used to reduce the cost of a system composed on high capital cost, low marginal cost dispatchable generators like nuclear. Charge the EV's and run heat pumps to warm thermal storages during the night when demand is lower, say.
    - _ph_ 6y ago
      Yes, demand response will play a huge role in the grids of the future. But when you say "current versions", which current operating nuclear plant achieves this ramp speed? Also, it means you have to run your reactors regularly at below 100%, so you still can react on additional demand, which increases further the cost of a very expensive technology.
      - jabl 6y ago
        > But when you say "current versions", which current operating nuclear plant achieves this ramp speed? IIRC that 5% figure I read was wrt EPR and AP1000, presumably older generation LWR's are slower, by how much I'm not sure. France has run older generation PWR's in load-following mode for decades, but I'm not sure which ramp speeds they achieve; fast enough in practice in any case it seems. CANDU reactors in Canada have steam bypass and can apparently ramp at >10%/min. In any case, my point is that ramp speed is in practice not a technical limitation. Of course you want to run a generator with high capital cost but very low marginal cost at 100% as much as possible, but if you now and then need to ramp (say, if the wholesale price goes negative) you can do it. > Also, it means you have to run your reactors regularly at below 100%, so you still can react on additional demand, which increases further the cost of a very expensive technology. To be clear, I'm not advocating a 100% nuclear grid. I'm just pointing out that the "nuclear can't ramp and is thus unsuited for the grid of the future" isn't correct. In particular, I think solar and a moderate amount of storage is very well suited to cover the daily variation in many parts of the world. I also think that dispatchable low-carbon sources (which could be hydro, or nuclear, or something else like geothermal where available, CCS where geological formations for storing CO2 are available, etc.) have a role to play in least-cost deep decarbonized grids. See e.g. https://doi.org/10.1016/j.joule.2018.08.006 https://doi.org/10.1016/j.joule.2018.08.006
  - p_l 6y ago
    A lot of the costs is politics, and second-order effects from lack of production lines making everything a one-off. Which "funnily" enough makes it so that the more dangerous reactors remain in use for longer, as the new designs aren't built, despite huge safety improvements (even if you go just for late 1970's self-sealing molten lead/bismuth reactors). Overcapacity is a problem, especially for low-enriched reactors, but that's why it shouldn't be the only answer.
- imtringued 6y ago
  Are you joking? Building nuclear power to cover peaks is insanely uneconomical. More expensive than building a nuclear power plant in a flexible grid. If you don't know anything about how a grid functions then maybe you should stop shoehorning a single solution to solve every problem when everyone is already aware that a large array of different technologies is necessary for a modern grid.
- p_l 6y ago
  If you have more production than demand you need to store it somewhere, which is exactly the point of such projects, if only to prevent network desynchronisation that causes brown/blackouts due to power flowing in different way than you want in the grid. Energy storage has also been planned for nuclear power plants as starter and emergency power.

rsync 6y ago

You'd compare the relative simplicity and complexity of a nuclear reactor to this "dig a hole in the ground and drop a weight" scheme ? Regardless of your thoughts on Nuclear, this is clearly a much simpler device. Also, I suspect the failure modes in this are pretty boring ...

reegnz 6y ago

Exactly. Most people just don't want to accept the fact that when it comes to energy density, nothing compares to nuclear. Nothing even comes close. https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/ https://dothemath.ucsd.edu/2011/11/pump-up-the-storage/

dave333 6y ago
even if nuclear had no contamination horrors, this is no longer true. Hydrino energy is much more energy dense and will be the ubiquitous portable power source for the 21st century and beyond. https://brilliantlightpower.com/news/ https://brilliantlightpower.com/news/
- reegnz 6y ago
  My comment might be read as 'Nothing will EVER compare to nuclear'. While in fact what I meant was 'CURRENTLY nothing scientifically viable compares to nuclear.' I do have high hopes about fusion and molten salt thorium is also up there as something I'd like to be further explored. But currently nothing up and coming seems to compare to nuclear. I just did a quick skim of the wikipedia page of that 'hydrino' stuff: https://en.wikipedia.org/wiki/Brilliant_Light_Power#Criticism https://en.wikipedia.org/wiki/Brilliant_Light_Power#Criticis.... I'm not an expert, but reading those criticisms makes me think this is nothing more than a money grab scheme without delivering anything usable for the past 30 years. Also, this thread: https://news.ycombinator.com/item?id=24423103 https://news.ycombinator.com/item?id=24423103