"When we design something new, we are going to use the opportunity to go green. Likewise, we are squeezing as much green into what we already have as we feasibly can."
The more energy you use, the more you pay and the more you pollute. The corollary is equally true. Cybernest calculates that they are expected to achieve an overall energy saving of 34 percent a year by embedding green principles into the design of its newest data centre, Bellville 2.
Its carbon footprint will also shrink. Just by introducing free air cooling, one of the hottest new cooling techniques in the international data centre arena. Features such as this will save massive amounts of energy while dramatically cutting emissions of ash, particulates and carbon dioxide.
"Green aspects are important to us. When we design something new, we are going to use the opportunity to go green," says Althon Beukes, Executive: Infrastructure Operations. "Likewise, we are going to squeeze as much green into what we already have as we feasibly can."
To be able to do this, Cybernest has made a point of measuring every resource it consumes and then calculating the associated costs. "Costs must be put into the context of measurements," says Beukes. "If you don't know what you're consuming, you can't know where your costs are sitting or what impact you are having on the environment."
Without accurate measurements, many IT users remain blissfully unaware of how much of their money might be going up in smoke as a result of energy inefficiencies.
Little do most IT users know, for instance, that the computing equipment itself consumes a relatively small part - around 30 percent - of the power used in the average data centre. UPS typically consumes 18 percent and PDU five percent, with by far the biggest energy users being the cooling systems. Their average share of data centre energy consumption is as high as 45 percent.
This explains why Cybernest is so particular about measuring and analysing its energy use, and why it has a strategy at Bellville 2 for each energy-consuming domain - cooling, UPS and the IT equipment.
As the biggest drain on energy supplies, cooling systems get close attention, with both free air cooling and hot aisle, cold aisle containment in use at Bellville 2.
At legacy centres, the standard air conditioning system is a water-based chiller plant. At Bellville 2, two cooling modes are in place: the usual chiller system and free air cooling. The latter is used on days when the ambient temperature outside is less than 24 degrees celsius. On these days, cool outside air is filtered in and hot air is vented out, estimated to save approximately 4,7 million kWh a year.
The temperature inside most legacy centres tends to be so cold as to be uncomfortable because the chillers blast frigid air at everything inside, not just the computers. New-generation centres are more selective. As Althon Beukes puts it: "They don't cool everything, only the components that need cooling".
Using the principle that hot air rises and cold air sinks, they have alternating hot and cold aisles, with each cold aisle blowing cool air upwards through the floor and a hot aisle above, sucking warm air out through the ceiling. The components needing cooling are positioned to face the cold aisle, ensuring the ultimate use of cool air flowing in and hot air flowing out.
