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Our data centers now work harder when the sun shines and wind blows

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Re: Our data centers now work harder when the sun shines and wind blows

#71

Post by gbear605 »

shadowgovt wrote: post #35
bizzleDawg wrote: post #18

It seems that it must be a really difficult problem to work out the optimal solution for having spare capacity to allow time/location shifting of workloads to minimize carbon per unit of compute. This Dell paper[0] suggests that 16% of the carbon over a typical server lifecycle is from the manufacture, so you probably don't want a server sitting there unused for 23 hours per day, since the overall carbon/compute rati…

Carbon consumed in building a server is sunk cost and would be paid independent of whether the server does any kind of carbon-footprint-aware load shifting. Assuming the server is "sitting unused for 23 hours a day" is the wrong model for what this work changed. You're assuming the server could be running at 50% duty cycle vs. 100% duty cyle. It isn't; since we're talking the batch load, there's a roughly fixed amoun…

Suppose I'm building a new datacenter that I want to do some constant amount of work each day. It doesn't matter the time of day. I can either power it with solar power, in which case it will run for 1/Y of the day, or with coal power, in which case it will run 100% of the day. If it only runs for 1/Y of the day, then I will need to buy Y times as many computers in the solar scenario than in the coal scenario.

If Y = 2 and only 16% of the carbon in a typical coal-powered computer's lifetime is from the manufacture, then solar makes sense - solar is 2*16% = 32% of the carbon of coal. But if Y = 10 - so it's running 10% of the time, meaning there need to be 10x as many computers built - and 16% of the carbon is from the manufacture, then solar power is actually worse for the environment than coal power: solar takes 60% more carbon than coal power.

Of course, this is a vastly simplified situation, but it points to the idea that we need to at least consider the carbon cost of manufacturing.

Re: Our data centers now work harder when the sun shines and wind blows

#72

Post by saagarjha »

skummetmaelk wrote: post #33
floatrock wrote: post #25

Earlier quoted context omitted.

> Aluminum Foundries in particular are extremely power intensive and have been run during off-peak times (or are built in areas with cheap plentiful electricity like nearby hydro-electric dams). Fun fact: this is a big reason why aerospace congregated in the pacific northwest during WWII (eg Boeing in Seattle). Aluminum is key to aircraft because it's lightweight, and at the turn of the century the US went on a dam-b…

Another fun fact: in 2018 the US produced 890,000 tons of Aluminium. Iceland (population ~350,000) produced 870,000 tons.

Is it Iceland’s insatiable desire to produce aluminum, or an abundance of geothermal energy?

Re: Our data centers now work harder when the sun shines and wind blows

#73

Post by saagarjha »

user5994461 wrote: post #38
sambroner wrote: post #4

Seems like an intuitively good idea to me! It'd be great to see how effective this change was. Regardless of this change, I wonder if they share their forecasted non-renewable energy needs with their energy supplier so that the energy supplier can prepare for changes to the expected base load. Do any factories or other energy intensive operations do this?

Having worked in a factory before, I can tell you that the factory was calling the electricity company before shutting down or turning on the factory. It is consuming a noticeable chunks out of what the whole surrounding city is consuming. Given how much electricity a datacenter consumes. Google surely must have a direct support contact within the electricity provider and they better start working both ways, if they…

And reactors aren’t generally easy or desirable to adjust.

Re: Our data centers now work harder when the sun shines and wind blows

#74

Post by generatorguy »

awild wrote: post #59
Klathmon wrote: post #7

Earlier quoted context omitted.

It's probably not at the same level of granularity that Google is trying to accomplish here, but I believe that power-hungry commercial systems have tried to move to when power is cheapest for many years now. Aluminum Foundries in particular are extremely power intensive and have been run during off-peak times (or are built in areas with cheap plentiful electricity like nearby hydro-electric dams). Still, i'd love to…

I imagine this could result in a feedback loop between the power plants scheduling and your devices scheduling if enough people use it.

Wind, solar, and run of river hydro are unscheduled so if load ramps up due to renewable generation ramping up there is no change in load to be accommodated by dispatchable scheduled units.

If the load responding to increased renewable generation exceeded the generation then the excess load should have just run whenever it was convenient since it isn’t using renewable power anyway.

I’ve omitted nuclear and large hydro from my discussion even though their fuel doesn’t emit carbon.

Re: Our data centers now work harder when the sun shines and wind blows

#75

Post by 205guy »

This is the future. Using algorithms to optimize usage of renewable energy. Not only will it be lower carbon, it will be cheaper. What's interesting is they describe it working on forecasts (for wind and sun) instead of instantaneous renewable production. I wonder what the rationale for that was? Basing the algorithm on instantaneous information should be more accurate and thus give better savings, but maybe it varied too much to reliably run the loads they want.

Imagine when your fridge can do this: freeze extra cold when the sun is shining (or wind is blowing), don't run the compressor when it's not, only run the blower after you open the door to move that extra cold from the freezer, allow a slightly larger temperature range, and of course run as necessary to avoid spoilage. It's not a simple algorithm, it has to handle various timeframes, such as solar being a daily cycle except there's less in winter and can go for a week or more with very little (storm/overcast). Maybe it could also use a bit of "learning" like the Nest thermostats to also optimize predicted usage.

I know of one commercial product that sort of does this: the Zappi electric car charger. If you have grid-tied solar, it measures the current being fed back to the grid and adjusts the charging current to match. So if a cloud goes over your house, or you turn on a big appliance, the charger reduces the power to the car by the same amount. This maximizes the use of your own solar energy and minimizes the use of grid energy.

https://myenergi.com/product/zappi/

Re: Our data centers now work harder when the sun shines and wind blows

#76

Post by ajpgrealish »

gambiting wrote: post #57
pbhjpbhj wrote: post #49

Earlier quoted context omitted.

In the UK households used to be able to get economy 7 electricity, which meant cheap electricity at night (I'd guess for 7 hours?). I've wanted to have realtime pricing like that for a while, it seems to be becoming available again. I honestly thought that was what the advanced electricity meter roll-out was going to do; but it seems not. More direct energy cost to service price charged seems like a good thing in gen…

With Octopus you can go to an Agile tariff, where you're paying exactly what the market rate is, which means that frequently at night you are being paid for using electricity(the rate per kWh goes into negative). I know a few people who have it with an electric car, and it means that at certain times you are being paid to charge your car. It's crazy. But also it means that at peak times the cost can be as high as 25-…

There are apps that can automate this whole process for you, monitoring the charge your cars needs each night and the dynamic energy prices either on an Economy 7 or Agile tariff and then controls the charging to optimise the price. If you're car needs less charge than your off peak rate time period then it will charge at the lowest carbon times. https://ev.energy

Re: Our data centers now work harder when the sun shines and wind blows

#78

Post by WalterBright »

205guy wrote: post #75

This is the future. Using algorithms to optimize usage of renewable energy. Not only will it be lower carbon, it will be cheaper. What's interesting is they describe it working on forecasts (for wind and sun) instead of instantaneous renewable production. I wonder what the rationale for that was? Basing the algorithm on instantaneous information should be more accurate and thus give better savings, but maybe it varie…

> Imagine when your fridge can do this

I've been posting for years that an effective grid "battery" is internet connected refrigerators, water heaters, A/C, car chargers, etc., that only run when power is cheap, i.e. when solar/wind is providing excess power.

A great deal of our demand for electricity is elastic and shiftable, which will eliminate a huge chunk of the need for grid batteries.

Glad to see this finally gaining some traction!

Re: Our data centers now work harder when the sun shines and wind blows

#79

Post by vladd »

ben509 wrote: post #29

Optimizing for this is a perfect task to throw at a simple market. Especially because actually reworking the software to take advantage of resources at different times is often going to require a decent amount of work by engineers. One way to do it would be assign various jobs a value, (which could be dynamic e.g. it might get more important as information becomes stale) and have them bid on compute power. You could…

> One way to do it would be assign various jobs a value. Or you could use real money.

It's not the value of the outcome for that job that you're interested, but rather its sensitivity to a delayed latency in executing it.

For example, preemptively converting Youtube videos to a lower resolution with optimum compression to avoid having to do it in real-time (when video is played) at a crappy compression (to be fast), is valuable for sure. It's just that it can be postponed for 24 hours without real impact. Executing a search for a single user is less valuable in terms of overall impact but much more latency-sensitive.

(you can think of value and latency-sensitive in terms of two dimensions that are independent between them.)

This idea helps save the planet for sure, but it requires cloud-providers to build APIs that enable devs to switch from the "here's the SSH to the server, do what you want with it" to a model where it's the devs that say instead "here's a lambda function and its desired latency execution, please schedule to run it for me and let me know when the result is ready" ( https://en.wikipedia.org/wiki/Inversion_of_control )

Google was able to do that because it owns a large part of the jobs executed in their datacenters. Hence they could build this adaptive scheduling for their own jobs quickly without necessarily passing through a cloud-based API that inverts the control of job scheduling.

Re: Our data centers now work harder when the sun shines and wind blows

#80

Post by walshemj »

mikepurvis wrote: post #55
pbhjpbhj wrote: post #49

Earlier quoted context omitted.

In the UK households used to be able to get economy 7 electricity, which meant cheap electricity at night (I'd guess for 7 hours?). I've wanted to have realtime pricing like that for a while, it seems to be becoming available again. I honestly thought that was what the advanced electricity meter roll-out was going to do; but it seems not. More direct energy cost to service price charged seems like a good thing in gen…

TOU pricing is pretty widespread at this point; I have it in a medium-sized city in Canada, and intentionally run laundry (electric dryer) in the evening when power is half the cost of daytime use. With EVs coming online and being set up to charge at night, it would definitely be nice to have a minute by minute spot pricing scheme, though, then you'd basically have a mechanism for using the chargers and other intelli…

I think when widespread overnight charging of EV's is a thing cheap evening electricity will be phased out
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