Comment by bob1029

Comment by bob1029 a day ago

12 replies

From a purely engineering perspective I think it becomes difficult to argue with the gas turbine once you get into the gigawatt class of data center. The amount of land required for this much solar is not to be understated. In many practical scenarios the solar array would need to be located a distance away from the actual data center. This implies transmission infrastructure which is often the hardest part of any electrical engineering project. You can put a gigawatt of N+1 generation on a 50 acre site with gas. It's dispatchable 24/7/365 and you can store energy for pennies on the dollar at incredible scale.

Having both forms of generation available at the same time is the best solution. Once you put a data center on the grid you can mix the fuel however you want upstream. This should be the ultimate goal and I believe it is for all current AI projects. I am not aware of any data center builds that intend to operate on parking lot generators indefinitely.

dan-robertson 20 hours ago

For inference you don’t need gpus to be clustered together as much (generally training has lots of synchronisation steps so you can be bottlenecked on that instead of ‘real’ work) as they can handle separate tasks in parallel. But maybe other economies of scale still make you want to put them together (and therefore on average further from the power).

I guess there was a bit of thought about transmission with the reference to high voltages. Another interesting thing: batteries allow you to reduce the needed capacity for transmission lines – if you have batteries near generation and then transmit power at a lower maximum, same average rate than if you only have batteries near use, you can more efficiently use the available transmission.

I guess the main reason for gas to be a problem is if you can’t get new generation (eg lack of turbines).

hjoutfbkfd a day ago

they are talking about covering the desert with solar panels. why would you not put the data center in the middle of it?

  • bob1029 a day ago

    Dust, high ambient temperatures, latency, accessibility.

    I think the dust is the worst part in terms of operational concerns.

  • sethops1 a day ago

    Simply because latency is a competitive advantage, one worth paying for. At the speed of light, making a trip out to the desert and back is too slow.

    • hjoutfbkfd a day ago

      20 ms extra, for models which respond in 5 minutes

      • stogot a day ago

        Right It is a use case where humans are not latency sensitive

matt-p a day ago

Sadly, I agree until we get SMRs (I think we are few years off). Obviously it would be more ideal to use grid+solar with curtailment but not super realistic.

cinntaile a day ago

If you have predictable demand at that scale, nuclear might make more sense than the combination of gas and solar.

  • leetrout a day ago

    I am hoping nuclear batteries make a comeback by the desire for all this compute and its voracious appetite for energy.

    • alansaber a day ago

      We have rolls royce small modular reactors (SMRs) driving a similar functionality in the UK

      • stephen_g a day ago

        For context, at the moment they hope to have them operating some time in the 2030s. That’s a best case, just like the cost estimates (which operating practically and safely may be more than what people are forecasting)

        Not operating today like it sounds from the comment.