Raised-floor cooling has been deemed by experts as an inefficient method of mitigating heat in datacentres, but Australian Securities Exchange (ASX) general manager for technology infrastructure Fraser Marsh doesn't agree with this view.
Marsh runs the ASX's Australian Liquidity Centre (ALC), a bespoke tier 3 datacentre in Artarmon, Sydney. As well as housing ASX's IT gear, it also offers co-location space for customers that want their own IT equipment closer to ASX's trading platforms.
The datacentre is at around 70 per cent capacity right now, with 70 co-location customers including international investment firms, brokers, and several managed service providers. The AU$36.5 million bespoke facility officially opened in February 2012, and is one of the many datacentres across the globe that still uses raised-floor cooling.
Industry pundits such as Schneider Electric's manager for the federal government and the ACT Olaf Moon and Gartner's chief of research for infrastructure David Cappuccio have deemed raised-floor cooling wasteful, while others have claimed that the datacentre industry should move away from air cooling altogether.
"With air, it requires more energy to push large volumes of heat away, but you only need small quantities of water to transport similar heat loads," Boorer told ZDNet.
Marsh acknowledged that there are other ways to cool his facility, but is happy with doing it through raised floors, which is still the predominant method for datacentre cooling. The data hall in the ALC is laid out in a hot aisle/cold aisle configuration to optimise management of heat coming from the racks with large vents under the floor that are 85cm deep pumping out large quantities of cool air.
"What we did is put all the cabling above the floor, so you have proper airflow," Marsh told ZDNet. "A lot of datacentres enclose their hot aisle to duct away hot air, then it goes back and recirculates — the power utilisation in the facility doesn't really require that.
"I think raised-floor cooling is still a perfectly viable solution for most organisations, to be honest with you."
The temperature within the ALC is currently at around 22-23 degrees Celsius, although the ASX is considering raising that by a little, according to Marsh.
Three 1.2MW air-cooled chillers are used to cool the water that goes into the air conditioners, providing the cold air through the floor vents. ASX decided against using water tanks or water chillers to avoid diseases such as Legionnaires Disease, which thrives in damp conditions, Marsh said.
"With water towers, you are susceptible to that, and there have been instances with shopping centres where they've had to shut down their systems because of a Legionella outbreak," he said. "We made a conscious decision away from that."
The ALC currently has 300 racks for co-location services to clients, with the ability to expand that out to 500 racks in the future.
Customers that value a low-latency connection to ASX's trading platforms find co-locating to the ALC extremely beneficial, according to ASX CIO Tim Thurman.
"If they want to trade on the Australian stock market, they don't have to leave and can do it all from this building," he said. "That's where the rest of the world is going in terms of trading — it's getting closer and closer to the trading platforms.
"One day, you might even see trading platforms as a community in themselves, with the technologies merged together, but that's way out there and could be 15 years from now."