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One solution is to rely on backup power supplies and batteries to charge and discharge, providing extra power quickly. However, much like a phone battery degrad

One solution is to rely on backup power supplies and batteries to charge and discharge, providing extra power quickly. However, much like a phone battery degrades after multiple recharge cycles, lithium-ion batteries degrade quickly when charging and discharging at this high rate. Is this really a problem for an industrial installation? I would imagine that a properly sized facility would have adequate cooling + capacity to only run the batteries within optimal spec. Solar plants are already charging/discharging their batteries daily.

jeffbee 1y ago
In addition to what you said, nothing is forcing or even encouraging anyone to use lithium-ion batteries in fixed service, such as a rack full of computers.
pixl97 1y ago
Eh, I think part of the problem here is the speed of load switching. From the article it looks like the loads could generate dozens to hundreds of demand spikes per minute. With most battery operated loads that I've ever messed with we're not switching loads like that. It's typically 'oh a fault, switch to battery' then some time later you check the power circuit to see if it's up and switch back. This looks a whole lot more like high frequency load smoothing. Really it seems to me like a continuation of a motherboard. Even if you have a battery backup on your PC you still have capacitors on the board for voltage fluctuations.
lstodd 1y ago
in a properly designed install you can actually use the compressors and fans for smoothing load spikes. won't be much, but why not. edit: otherwise I'm not getting what the entire article is about. it's as contrary to what I know about datacenter design as it can get. it's.. just wrong.
- touisteur 1y ago
  I'm thinking of sequences of 'put the sharded dataset through the ten thousand 2kW GPUs, then wait on network - all-reduce - then spike again - a mostly-synchronous all-on/all-off loop. Watching how quick they get to boost-frequency I can see where the worries come from.
  - lstodd 1y ago
    does anyone actually do those kind of loads over entire dcs? because if so, I have some nice east-european guys to teach them proper load-balancing.
    - 0cf8612b2e1e 1y ago
      Wouldn’t that situation arise when a company is training their top end model? Facebook/Google/DeepSeek probably trained on thousands of collocated GPUs. The bigger the cluster, the bigger the sync delays between batches as the model data gets shunted back and forth.
      - deleted 1y ago
        [deleted]
      - lstodd 1y ago
        basically it's a load-spreading problem. this can be mitigated entirely by control plane alone. unless you think they really do a cluster-per-datacenter and in that case, I cannot believe the DC in question were not designed for peak and transient loads both in AC and power supply. Besides it would be stupud.
        jwatte 1y ago
        Yes, the data center was designed for peak load. Unfortunately, the data center is hooked up to the grid. De-coupling that connection is what this article is literally about. Then again, some data centers just use re-generation from giant flywheels, where the grid powers the flywheel to build up inertia, and thus load can be smoothed that way. The flywheels need to keep running at 60 Hz for at least 30 seconds to give the Diesel generators time to start, should the grid fail. Run a flywheel at the main transformer, run batteries at your PDC and add supercaps at each point of load, and you may very well be able to show a much smoother load to the grid.
    - jwatte 1y ago
      Yes, they do, and no, they don't want to wait longer for the result just because you think they shouldn't.

jeffbee 1y ago

In addition to what you said, nothing is forcing or even encouraging anyone to use lithium-ion batteries in fixed service, such as a rack full of computers.

pixl97 1y ago

Eh, I think part of the problem here is the speed of load switching. From the article it looks like the loads could generate dozens to hundreds of demand spikes per minute. With most battery operated loads that I've ever messed with we're not switching loads like that. It's typically 'oh a fault, switch to battery' then some time later you check the power circuit to see if it's up and switch back. This looks a whole lot more like high frequency load smoothing. Really it seems to me like a continuation of a motherboard. Even if you have a battery backup on your PC you still have capacitors on the board for voltage fluctuations.

lstodd 1y ago

in a properly designed install you can actually use the compressors and fans for smoothing load spikes. won't be much, but why not. edit: otherwise I'm not getting what the entire article is about. it's as contrary to what I know about datacenter design as it can get. it's.. just wrong.

touisteur 1y ago
I'm thinking of sequences of 'put the sharded dataset through the ten thousand 2kW GPUs, then wait on network - all-reduce - then spike again - a mostly-synchronous all-on/all-off loop. Watching how quick they get to boost-frequency I can see where the worries come from.
- lstodd 1y ago
  does anyone actually do those kind of loads over entire dcs? because if so, I have some nice east-european guys to teach them proper load-balancing.
  - 0cf8612b2e1e 1y ago
    Wouldn’t that situation arise when a company is training their top end model? Facebook/Google/DeepSeek probably trained on thousands of collocated GPUs. The bigger the cluster, the bigger the sync delays between batches as the model data gets shunted back and forth.
    - deleted 1y ago
      [deleted]
    - lstodd 1y ago
      basically it's a load-spreading problem. this can be mitigated entirely by control plane alone. unless you think they really do a cluster-per-datacenter and in that case, I cannot believe the DC in question were not designed for peak and transient loads both in AC and power supply. Besides it would be stupud.
      - jwatte 1y ago
        Yes, the data center was designed for peak load. Unfortunately, the data center is hooked up to the grid. De-coupling that connection is what this article is literally about. Then again, some data centers just use re-generation from giant flywheels, where the grid powers the flywheel to build up inertia, and thus load can be smoothed that way. The flywheels need to keep running at 60 Hz for at least 30 seconds to give the Diesel generators time to start, should the grid fail. Run a flywheel at the main transformer, run batteries at your PDC and add supercaps at each point of load, and you may very well be able to show a much smoother load to the grid.
  - jwatte 1y ago
    Yes, they do, and no, they don't want to wait longer for the result just because you think they shouldn't.