Last night I went to an event at NESTA, the peak body fostering innovation in the UK. One of my key takeaways was a fresh realisation of the value of water. It’s suggested, in fact, that in the next few decades, fresh water will become one of the most valuable commodities on Earth. Wars will be fought over fresh water
Did you know it takes seven litres of water to make one litre of beer? Ten litres of water to create a litre of petrol. 1000 litres of water to make a television set. 8000 to make a pair of jeans. And 40,000 or more to make a car. You can read the interesting facts in detail here.
A great deal of attention has been focussed on the copious use of power of any industry that uses data centres. In our organisation, we’re swiftly moving the thinking model we use to build our systems from one where power is effectively unlimited, to one where we recognise that power is a primary constraint that we must manage across our application portfolio. No matter how advanced your green technology, there is an upper limit beyond which it simply isn’t possible to shove any more compute into a certain amount of space.
But until last night, it didn’t dawn on me that, just like power, water cannot be considered an unlimited resource. If it takes 40k litres of water to make a car, how much must be used up building us just one of the many mainframe computers we run?
It takes, according to this site, 45.4 litres of water to make a computer chip. I did some rough, back of the envelope calculations. Let us assume that a typical bank data centre has 400,000 chips. That’s assuming that the data centre is one of a reasonable scale and has about 20,000 CPUs across all the possible platforms deployed, and there are about 20 other chips supporting each CPU. That’s probably a low order number, but it means that the compute in the data centre took 18.16 million litres of water to create. I’m not even factoring in the data storage, the cooling, and the construction costs (in litres) of the actual facility.
If you’re a typical bank, you’ll be cycling your platforms every couple of years. Let’s say everything is refreshed every three, for our purposes here. That doubles the water consumption across a three year time frame for a huge 36.32 million litres of water, just for the chips.
If you are a bank with that sized data centre, you’ll probably have some millions of customers – let’s say 10 million. And at that point, we’re talking about 36 litres of water every three years, or 12 litres of water per year per customer to have a banking relationship.
That’s a very low order number, given the assumptions above. Clearly, the real number of litres will be much, much higher.
In other words, you can make a litre of petrol with less water than it takes to run a bank account for a year. Going back to the initial point of this post, if water becomes one of the most valuable commodities on earth, using that much just to run a banking relationship is going to become uneconomic. It also goes to show that green agendas are, as predicted by practically everyone, just good business sense.