I have been writing about some pretty cool ways to save electricity in our house. What’s remarkable is that many of the ones that save the most are low-tech and not very obvious. I found them mostly by using two meters: a Kill-a-Watt and a PowerCost Meter; it wouldn’t have been obvious to me without them. So when I read this article, I was pleased to see that UPS has reduced their annual electricity expenses in their data centers by 3 Million kWh. That’s a lot of kWh!
In a data center, where lots of computer servers are running, you need to provide electricity for all the computers … which generates heat … that you have to get rid of my keeping the air cool around the computers. This very web page was served to you from a computer running in a data center somewhere, probably Texas. Big data centers have thousands of computers — it’s amazing to see, and they use a lot of electricity. The EPA reports that data centers use 60 – 70 Billion kWh per year, which is about 5% of the total use of household electricity. Yowza!
So when UPS looked at one of their data centers, they found two things. First, when they kept the cooled air only where it was needed, they needed to cool less air. High-tech solution: put a Plexiglas top over the top of a cabinet to prevent escape of cooled air. It might sound obvious, but they looked, and found huge amounts of pointless waste. And fixed it. I bet you can do the same in your house (or your data center!).
The second thing was that they took advantage of outdoor temperature to provide chilled water to cool the space using a pretty simple device: a heat exchanger. A heat exchanger is just a fancy way of saying cool air (also works with water) is used to cool down something else. It might seem even easier just to pump cool air in from outside, but things like humidity and air cleanliness are important in a data center. But again, a simple solution to a problem reduced waste by a lot.
In the end, UPS is saving about 3M kWh per year from these changes, or about $110M. Not to mention 1,000 tons of CO2.
They key is, you have to look. Some changes are hard and expensive. But some changes are simple and cheap. Write the most unusual thing you found in your house in comments.