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Google is investing $3.3B to build clean data centers in Europe

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Re: Google is investing $3.3B to build clean data centers in Europe

#142
What'd be better for the environment is to not build anything at all, and force people to use existing resources more efficiently through higher pricing rather than buying more resources to run at 1/30th the speed a real programming language would be able to do. Not a realistic proposition, but let's not get taken by the narrative that a multi-megawatt datacenter can somehow be as green as they claim, once you consider the downstream effects.

Re: Google is investing $3.3B to build clean data centers in Europe

#143
post #87

Earlier quoted context omitted.

A heat pump is basically an air conditioner running backwards - it runs uncompressed refrigerant through a radiator outside to pick up heat from the outdoors, and compressed refrigerant through a radiator indoors to release the heat. Because they can move more heat than they dissipate (and some of the dissipated heat is indoors anyway) they can be more than 100% efficient. (edited to fix compressed/uncompressed sides…

(disclaimer: physics noob) If a Stirling engine can be operate at 50% efficiency and a heap pump can operate at 400% efficiency, could we take a source of heat (e.g. heat side product of computation instead of burning fuel) use it to power the Stirling engine and use the movement of the Stirling engine to power a heat pump and thus turn computation into house heating at effective 200% efficiency? (under whatever assu…

Yes and no.

A heat pumpt doesn't generate heat, it /pumps/ it from one location to another. It can only achieve above-100% efficiency if you don't include the source of the heat in your calculation.

For a more practical example, consider a (simplified) geothermal heating system. It consists of a probe that's drilled some 10-15m into the earth, a radiator in your living space as well as a pump and piping connecting the two. The earth's temperature surrounding the probe is relatively constant at 10-15 degrees C.

In winter, when the outside temperature falls below those 10-15 C, you pump warm water from the probe into the radiator. Using the example numbers, 100W of electrical energy might provide you with 400W of heating output. The 100W has no part in generating the heat though, it only moves it from the warmer probe to the cooler radiator. The reverse applies in Summer, when the surface temperature is higher than 10-15 C.

What you're describing exists in the form of district heating. Heat is generated in a central location (e.g. as a side product from garbage incinerators), and a heat pump is used to transfer the thermal energy from that location into a bunch of surrounding houses. But, in any case: the whole process only makes sense as a way to capture excess energy from the heat-generating process; and you are always limited to (at the theoretical maximum) capture all of the excess energy output, but not one Joule more.

Re: Google is investing $3.3B to build clean data centers in Europe

#144

Bravo to Google for this show of corporate leadership. Their pledge to purchase renewable energy to match their real-time demand really is impressive, especially the note that it must create new renewable generation (discussed on the Google blog announcement not this article) . It is also prudent, as these long-term power purchase agreements (PPAs) with new renewable generators will be very competitive, probably much…

I wonder, would it be feasible for them to use wind power to run time insensitive batch jobs in the daytime - crank down the processing power on these jobs when there's less green energy around?

Not impossible, but I doubt it.

(1) Existing power usage doesn't work that way. You're basically on the hook for a predicable amount of usage. Of course, this could change, but the inertia behind this paradigm is high.

(2) Google has a bunch of hardware with relatively fixed costs that they'd prefer to run 24 hrs/day, 365 days/year.

Re: Google is investing $3.3B to build clean data centers in Europe

#145

Earlier quoted context omitted.

To very good approximation, 100% of the energy used by a contemporary computer is turned to heat. The amount of negentropy generated by the computations is utterly dwarfed by the increase in entropy in the computer's surroundings. Computers are space heaters that happen to do some calculations as a side effect.

I wonder if WD and friends do generative braking on the hard drives.

Spin them all up when the wind blows and convert their kinetic energy to power during a lull.

Re: Google is investing $3.3B to build clean data centers in Europe

#146

Earlier quoted context omitted.

To very good approximation, 100% of the energy used by a contemporary computer is turned to heat. The amount of negentropy generated by the computations is utterly dwarfed by the increase in entropy in the computer's surroundings. Computers are space heaters that happen to do some calculations as a side effect.

I do realize that and I still don't get how doing computation is supposed to increase the energy efficiency of heating. Are you trying to reduce wasted energy while heating by diverting it to computation, or are you trying to avoid wasted energy in computing by utilizing the otherwise-wasted heat? It seems like you're optimizing the cost efficiency of computation while claiming it improves the energy efficiency of he…

Computing is heating, but with benefits, to a rough approximation.

The components inside the computer do something with the electricity, which results in it being turned into heat. So by doing useful computing and using the created heat as a result for heating something, you've effectively made the heating free, to the degree you can use the computing for something useful.

Re: Google is investing $3.3B to build clean data centers in Europe

#147
post #146

Earlier quoted context omitted.

I do realize that and I still don't get how doing computation is supposed to increase the energy efficiency of heating. Are you trying to reduce wasted energy while heating by diverting it to computation, or are you trying to avoid wasted energy in computing by utilizing the otherwise-wasted heat? It seems like you're optimizing the cost efficiency of computation while claiming it improves the energy efficiency of he…

Computing is heating, but with benefits, to a rough approximation. The components inside the computer do something with the electricity, which results in it being turned into heat. So by doing useful computing and using the created heat as a result for heating something, you've effectively made the heating free, to the degree you can use the computing for something useful.

OK, I think I see why we're seeing this differently. The only way this actually saves energy (instead of merely money) is if, later in the future, you would've actually wasted the heat that would've be produced if your initial goal had been computation. In that case, yes, it's true that doing the computation now and using it for heat is better. My assumption was that you would be already using any heat you generate from computation for heating regardless, so it didn't make sense to me that, in other situations where your goal is only heating, adding computation to the problem would save any energy.

(Sorry this is complicated to explain, I hope it makes sense. Regardless, I get your point.)

Re: Google is investing $3.3B to build clean data centers in Europe

#148

Earlier quoted context omitted.

Following this logic, I often thought electric heaters are a waste of energy since they perform no computation. But a French company is having a go at this: https://www.qarnot.com/computing-heater_qh-1/

Couldn't the heat also be used to generate more electricity?

No, because you need to be able to exploit a temperature difference to convert heat into other forms of energy.

Conversion efficiency is proportional to the difference in temperature, so for most wate-heat scenarios, electricity generation is either non-functional, or barely functional, but impractical. In a lot of scenarios you end up interfering with the efficiency or longevity of whatever you were trying to cool in the first place.

Re: Google is investing $3.3B to build clean data centers in Europe

#149

These data centers will collect large amounts of personal data. I believe that the future of personal privacy protection issues needs to receive greater attention.

This is not on topic.

These “omg privacy!” flavor of off topic post seems predictably standard for anything with “google” in the title.
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