There are many ways that you can address energy efficiency in data centres, but an article in The Data Center Journal suggests that the best place to start is the lights.
One of the easy quick wins for saving money in a data centre is to simply turn the lights off. In the past data centres have been permanently lit, despite the fact that no one enters a room from one day to the next. The savings may not be huge, 3-5% of the power requirement when the impact on cooling requirements is taken into account, but why waste it?
But the article, from Sam Klepper, EVP of Building Solutions and CMO for Redwood Systems, goes further, placing lighting systems at the heart of data centre energy monitoring.
We’re not talking about standard, switched light bulbs, but an intelligent lighting system based on networked LEDs. These devices last longer, generate less heat and are connected via a direct current(DC)-powered network. One of the main advantages is that the network can also incorporate multiple sensors that can accommodate countless specialised features. Once the lighting platform is in place it supports a range of building intelligence applications.
The article says that switching to an energy-efficient lighting network that integrates building-performance systems can result in improving PUE by up to 25%.
Well, the savings aren’t from the lighting system itself, but from the ability to monitor the environment and identify where actions should be taken. This is one of a number of approaches to monitoring the data centre, some addressing the facility as a whole and some more directly monitoring (and managing) IT and other equipment.
Much depends on other energy-reduction initiatives to address the PUE. For example, running systems hotter, which is something Intel has been talking about a lot recently. Facebook refitted its Santa Clara data centre to operate at 27°C, which saved $229,000 in annual energy costs. But you really need to be sure that complete systems will be reliable at higher temperatures, which needs more than just Intel’s say-so.
The other main alternative, and one that is gaining considerable momentum, is to use the external environment to cool the data centre. Much easier to do if you’re building a new facility (more on that in a post in a day or two), less so for refits. And it depends on location. It can dramatically reduce PUE, and hence energy costs, in one fell swoop. It’s also much more under the control of the data centre manager and still leaves lots of room to make the IT infrastructure itself more efficient.