Ask HN: Which is better. A server farm somewhere hot or somewhere cold? | Hacker News Reader

Ask HN: Which is better. A server farm somewhere hot or somewhere cold?

5 pointsed2098 comments

Two recent articles caught my eye today. Both about new server farms being built/upgraded.

One is somewhere hot (North Carolina, Apple) [1]

The other is somewhere cold (Sweden, Facebook) [2]

Hot, (assuming more solar energy available) benefits are increased power from a solar plant but the farm requires more cooling. Cold, requires less cooling therefore less energy.

It's interesting [to me at least] because it raises the question of efficiency. i.e. do you build something that requires loads of power - but who cares 'cos we got tonnes of renewable energy... or do you try an require a lot less energy even though hydroelectric is not damaging to the environment the more you produce.

[1] http://arstechnica.com/apple/news/2011/10/apple-building-171-acre-solar-panel-farm-to-power-nc-data-center.ars

[2] http://www.techiespider.com/2011/10/27/facebook-build-server-farm-northern-sweden-arctic-circle/

Maiden, North Carolina is temperate, not warm.

December 2010 data for Ashville, NC:

   Average Daily High = 38.4F 
   Average Daily Low = 22.8F
   High = 50F
   Low = 11F
   1087 degree days of heating
   10.8" of snow, 7" maximum depth.

Source: http://www.nws.noaa.gov/climate/index.php?wfo=gsp

Data for Greenville Spartenburg for December 2010 is similar but with less snowfall locally.

If your data centre uses less energy than your renewable energy source, then you can push the excess out onto the grid. Similarly, if you use more than you can produce, you have to pull the deficit from the grid. Either way, the less energy you use, the more energy has to be generated elsewhere. So energy efficiency still matters.

Against that, there are transmission losses. If your data centre in a cold dark place is powered by a solar array in a hot sunny place, you need less energy to spend on cooling, but you have less energy to spend because more energy will be lost in transmission. I don't know how they balance out.

(And if you have enough clients in the hot place who want low latency, it makes sense to put the data centre in the hot place even if it's less energy efficient.)

I'd venture a guess that the solar energy provided wouldn't even cover a quarter of the energy cost required to cool a data center.

I'd go on to say that the energy coefficient between 35 Deg N and 55 Deg N probably isn't enough to offset the equation significantly.

As such I think that removing heat more efficiently via naturally cold climates would have a greater impact on bottom line. Check out wikileaks cave-based data centers in old Swedish nuclear bunkers. http://bitshare.tumblr.com/post/2383169988/the-wikileaks-ser... (Sweden's bandwidth to the rest of the world also blows ours away.)

An ambiguous question that does not consider the requirements.

eg Latency vs cost.

Being based Antarctica can be very cheap and fast. But there's poor connections.

It's like a PHP vs C++ argument. While C++ is secure, efficient and takes longer to implement while PHP is cheaper, faster to implement for MVP.

tl;dr: Doing science with servers in bulk? Better in cold. Doing business? Better more closer to customers that tend to be in warm places.

Either way, if you are using renewables, you are going to be using a baseload renewable power source (geothermal/hydro) that isn't going to care about temperature.

What you want is access to cheap electricity and cheap cooling. Whatever minimises TCO is where you want to be.

I know that electricity in northern Sweden is relatively (very) cheap due to the effective water power plants in the area. They work all year and I can imagine that they are cheap compared to solar panels. So: cheap electricity + neutral cooling = happy zuck.

A kind-of third option is what I believe Google have done, near a hydroelectric plant (that used to be used for smelting?), and near a city with a major internet exchange.

Why couldn't you place it in a cold windy place? Solar is not the only renewable energy.

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