Data Centres: the invisible problem
One of the main challenges of the modern day is how much of our lives are now invisible to us. There was a time when energy was visible: Logs burning in a fireplace, for example. There was a time when pollution was visible: Black smoke billowing out of a chimney, maybe. And there was a time when data was obvious: Stacks of paper on your desk. In some senses the world has become more and more invisible to us, transformed into a maze with hidden walls. This makes conceptual challenges like ‘why save electricity’ more difficult, because for most of us electricity is magic: You plug something in, turn it on, and it works. Even when we understand the impact of our own personal energy use and seek to save power in our own lives, we often can’t see all the ways we impact the world with our energy use, because everything we use these days is invisible. Take data for instance.
The cloud of power consumption
Data is one of the fastest growing business sectors in the world. After years of wondering where the ‘office of the future’ was, as we still dealt with paper for just about everything, the tide seems to have turned and the Cloud has come. Data seems like a weightless, formless item of infinite size; when you need more space for music and videos at home, you simply buy a new hard drive – or, more and more common these days, you buy a Cloud service from a company like Amazon or Dropbox. Data has almost no physical presence in your life.
Yet it has a very real physical impact. Data is stored on servers in Data Centres. Not only do these servers consume electricity to run, of course, but they also generate immense amounts of heat, and when dozens or hundreds are combined in one space, the heat issue is a difficult one to deal with. The servers must be maintained at a cool operating temperature or they will malfunction. So data centres represent several invisible problems: The resources required to manufacture these delicate machines, the electricity required to run them, and the power needed to cool them down and keep them running.
Data Centres: the growing energy efficiency problem
The number of Data Centres in the world is expected to double within the next two to three years, and they represent an immense drain on energy resources. Currently there are only about 13,000 data centres in the world and yet they already represent about 1.2% of the world’s energy consumption. In England, the country is expected to reach ‘maximum power’ by 2015 and already purchases 20% of its power from France in order to keep up with the demand. As Data Centres grow, the need to make them sustainable becomes increasingly difficult.
One of the key ways this can be achieved is by designing the data centres to be more efficient from the very start, by using natural cooling. Cooling servers down to efficient operating temperatures is where the largest power consumption occurs in a data centre, and using outside air to cool the interior or to chill water-based cooling systems can have a tremendous impact on the energy efficiency of a data centre. Google, one of the leading data centre companies in the world, has located many of their data centres in geographically cold climates to take advantage of the natural cooling of cold air from the outside.
However this approach does have its challenges. While natural cooling reduces the energy used in cooling a data centre to almost zero, it often requires that the centres be built far away from other infrastructure, which increases construction and maintenance costs.
In conclusion, Data Centres will constitute a larger and larger piece of our energy consumption picture as our lives move increasingly into the digital realm. Despite the fact this means we’ll no longer be able to see the direct physical evidence of our impact on the world as we go, reducing that impact becomes more important. The less we see, the more we have to do.