It’s no secret that data centres are energy intensive buildings. With the carbon tax to be introduced in July this year, they will increasingly come under scrutiny for their environmental credentials.
However, environmental savings don’t have to be difficult to achieve.
Engineering consultancy, Norman Disney and Young (NDY), recently completed energy audits of three data centres around Australia. It identified energy savings of up to 20 per cent which could be gained through measures such as energy sub-metering and monitoring systems to better understand energy consumption. Cycling outside air inside the data centre can also reap great benefits.
Chris Nunn, sustainability leader at NDY, says brush strips can also be installed around the edges of server racks and blanking panels to prevent air escaping. He says other initiatives can include:
• retrofitting motors with variable speed drives to enable recommissioning and better control of the way the mechanical systems distribute air throughout the data centre • carrying out airflow management, which includes maintaining layout diagrams and up-to-date stocks of panels to place into the floor tiles to prevent air flowing through holes in the floor
Minor initiatives can also help. For example, removing old cables which have built up on the floor over time but are no longer in use – cables can cause obstructions in airflow.
“Also, there’s new guidance from ASHRAE which specifies thermal guidelines for correct temperatures and humidities for cooling new computer equipment, whereas in the past those were quite restrictive,” Nunn says.
Although he recommends clients to adopt the expanded temperature ranges to gain energy savings, he concedes there is reticence from clients, perhaps due to existing contractual agreements.
Chris Seale, director of sustainability at Fujitsu, agrees and says new equipment is better able to handle higher temperature tolerances. “We’ve done work and studies on running the data centres hotter. As long as you get the atmospherics right, my understanding is there’s no problem with doing that,” he says.
Although energy consumption is the main focus of improving sustainability in data centres, Nunn says there can also be environmental savings in other areas, such as intelligent material selection, waste generation and reducing water consumption. He also predicts renewable energy sources, such as solar power, will become more popular due to the large, flat roofspace data centres have available and the decreasing cost of photovoltaic systems.
The introduction of the carbon tax is likely to force some companies to consider technology such as solar, with Nunn predicting a 1 per cent pass-on effect throughout the economy due to the tax. “So in the future we think price regulatory changes and energy price rises will mean the relationships between the clients and the data centre managers will have to change so that clients are taking responsibility for energy costs and data centre managers will be increasingly focused on reducing energy costs,” Nunn says.
However, Seale says the impact of the carbon tax is still relatively unknown and won’t fully understood until it has been introduced.
While it can be relatively straight forward to introduce sustainability measures into new data centres, retrofitting is a completing different ballgame. Nunn says “quick wins” can be gained, but it is by no means easy and most major environmental savings are gained through improving central mechanical plant and equipment. This requires large capital costs.
“While capital costs can be large – up in the hundreds of thousands of dollars – paybacks are quite good. Because of the energy hungry nature of the data centre, industry savings will pay back that capital investment,” Nunn says.
New sustainable technology will begin to filter through the industry as the focus on sustainability grows. For example, cooling high density server racks via liquid cooling. This delivers chilled water to “the hot side of a rack to remove heat using liquid, which is more efficient to pump around than it is to pump around air,” he says.
While he admits there is some reticence to utilise products which pipe water so close to server equipment, Nunn says it can dramatically increase cooling effectiveness.
In-rack cooling may also grow in popularity. “After that there’s going to be in-device cooling, so some people are estimating that the cooling’s actually going to be part of the devices as well,” Seale says.
“So whilst there might be some reluctance on that, I think it’s increasingly the direction that the IT industry is headed towards and we should anticipate seeing more of that.”
Some companies are leading the sustainability charge. NextDC will install up to 400kW at its M1 data centre in Port Melbourne, which will be the largest privately-owned solar installation in Australia. Fujitsu is also actively working towards bringing down its PUE – it is aiming for 1.7 for its data centres and has a target to reach an average for its Australian centres of 1.5 by 2020.
Initiatives by Fujitsu to help reduce its PUE include auto sensor lighting, using highly efficient lighting and has investigated using reflective paint on the roof space of data centres to help reduce heat absorption.
The company has also looked into installing trigeneration at its Western Sydney data centre, but Seale says any environmental initiatives must make business sense and initiatives such as renewable energy are evaluated on a case-by-case basis.
Nunn believes Australia’s current data centres are world class and steadily adopting energy efficient measures. However, legacy centres yield vast opportunities.
“I think the focus should be both on ensuring that all our new builds data centres are world class, continue to be world class, and in particular, upgrading our energy hungry existing data centres to take some of those best practice technologies and implement them where they’re not already in place,” he says.