This latest installment of our “How to Speak Like a Data Center Geek” series is about being green. The occasional puppet might tell you this isn’t always easy, but at Equinix we’re committed to environmental sustainability, whether it comes easy or not. And we think it’s critical that when we talk to people about what we’re doing to stay green, they know what we’re saying. That’s where the “geek” series comes in: to give our readers more fluency in data center language. The following entry defines a few terms people might toss around when they’re talking about green data centers, so that you can toss them back.
Power Usage Effectiveness (PUE): This is the standard measure of how efficiently a data center uses energy. It’s a ratio that shows how much power a data center uses for its customers’ IT equipment, compared to how much is going to overhead, including essential services such as cooling, lighting and power conversion. The more a data center can reduce its overhead – by delivering more efficient cooling, for instance – the lower it can drop its PUE. If absolutely no electricity was going to overhead, the PUE would be a perfect 1.00, but that’s impossible. At LD6 in London, which we’re opening next year, we’re shooting for a PUE between 1.10 and 1.25.
ASHRAE Thermal Guidelines: ASHRAE, which stands for American Society of Heating, Refrigerating and Air-conditioning Engineers, regularly updates guidelines on the optimal temperatures inside a data center to ensure the computing equipment performs properly. Equinix uses these guidelines as a reference in our newer facilities to ensure that we’re reducing our power consumption for cooling as much as possible, while still keeping the data center cool enough so things run safely and at a temperature level our customers are comfortable with.
Free cooling: One of the first things to know about free cooling is that it isn’t free, though it definitely is cheaper. Some background: The cooling systems at our data centers use chilled water to help produce the cool air we circulate among the equipment. The basic concept of free cooling is that when the outside air is cold enough, the system’s water can be chilled by that air, rather than by using a chilling compressor. That saves energy, but it’s not free because you still have to use fans to circulate the air and run pumps to move the water. Our AM3 facility in Amsterdam is one Equinix facility that uses free cooling.
Variable frequency drives (VFD): “Frequency” is directly related to a motor’s speed – the faster the frequency, the higher the revolutions per minute. A VFD enables a data center operator to vary both the frequency and the voltage being supplied to a motor to best fit the requirements of whatever function the motor is performing. At Equinix, VFDs are used in chillers, pumps and fans in our HVAC systems. They conserve energy by automatically reducing a motor’s speed and power draw when system loads are lower.
Read more about Equinix’s green data centers here.
Also, you may have heard we data center geeks have a thing for interconnection, since it’s essential for the enterprise to compete. Download Equinix’s IOA Playbook, which describes an interconnection-first architecture that securely connects people, locations, clouds and data.
And check out every post in the “Speak Like a Data Center Geek” series. (Please note: We welcome binge readers):
Part 7: Security and reliability
Part 9: Sustainability (see post above)