The Hidden Polluters
Most of us are blissfully unaware of the ‘silent CO2’ we are contributing to on a daily basis.
With more and more of our world moving online, the everyday services that we take for granted, are increasingly responsible for our CO2 emissions.
The culprits? Data Centres!
Whether it be Google, Facebook, Twitter or online banking, anything that requires online processing and storage requires some form of Data Centre to process it.
So what is a Data Centre?
They are essentially computers that process IT requests. These servers can range from just a single unit supporting a small office setup, to the gigantic ‘Server Farms’ operated by multinational companies. They usually employ security that would embarrass the average prison, and run state of the art back-up systems to ensure that the precious data is protected at all costs.
Data Centres already account for 2% of global CO2 emissions and are expected to surpass that of the airline industry by 2020.
This equates to around 1,963 billion kWh of electrical power.
Cisco forecast that that the fastest growing component of Data Centre traffic – global cloud traffic, will increase from 1.2 zettabytes of annual traffic in 2012, to 5.3 zettabytes in 2017. Overall global Data Centre traffic is expected to triple, reaching 7.7 zettabytes annually.
Just in case you were wondering 1 zettabyte = 1,000,000,000,000 Gigabytes
Now these are big figures that are not easy to get your head around. What’s clear though, is that these 'beasts’ are major polluters and there’s a big drive on to make them as ‘green’ as possible.
Because of the energy required to run them, designers are increasingly looking for ways to be more efficient. The industry figure used to measure a Data Centres efficiency is called Power Usage Effectiveness (PUE).
This is simply the power that the whole facility takes to run, which includes cooling, power losses, lighting and general power, divided by the power that is solely consumed by the IT equipment.
PUE =Total facility Load / IT Load
The ideal figure would be 1.0, however in practice this is not achievable, with most Data Centres, once fully loaded, somewhere in the region of 2.0 PUE.
Apart from the electrical power, cooling is also a big concern in Data Centres. The servers produce vast amounts of heat, and this has to be removed to avoid overheating. This is usually done via a chilled water system that effectively transfers heat from the inside, to the outside via chillers/coolers. This all requires energy.
A current trend is to locate Data Centres in places like Norway, Finland and Sweden. Google and Facebook have done just that. These are designed to take advantage of the so called 'free cooling' available in the colder climate, utilising the ambient outside temperature, or in some cases Arctic fjords, to cool as much of the chilled water as possible.
Although a step in the right direction, these ‘green’ Data Centres still consume vast amounts of energy in order to operate. A Data Centres main purpose is to protect data, and companies will often run more equipment than necessary, to minimise risk. A server going down can have massive financial implications, especially in the banking sector, and more importantly a loss of trust from its customers.
In this world, the servers stay up at all costs, no matter what.
So what for the future?
Data Centers are here to stay. Yes, they greatly contribute to worldwide CO2 emissions, but they serve an essential purpose in our online world by processing and protecting our data. It’s up to the designers to make them as efficient as possible.
Our modern world needs them, just don’t call them green.