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Interview: Christina Page explains how Yahoo keeps its datacentres green and clean

Yahoo's global director for sustainability explains why cloud providers need to get clued up on renewable energy

The environmental credentials of the datacentre industry are becoming increasingly scrutinised, with operators under pressure to reveal how energy efficient and reliant on fossil fuels their facilities really are.

For web services giant Yahoo, however, the datacentre has been front and centre of its company-wide efforts to reduce the size of its carbon footprint since 2007, reveals Christina Page, the firm’s global director of energy and sustainability strategy.

“When you look at our total carbon footprint as a company – from an employee commuting, air travel, office buildings and datacentre perspective, the datacentre is the place where we have the biggest opportunity to make an impact, and that is where we focus most of our attention,” she says.

The company started building and operating its own facilities around eight years ago, having previously leased space from other operators. It’s a move that has afforded the firm a greater degree of control over the location and design of the datacentres it relies on to run its services.

“Conventional wisdom said you needed to seal datacentres up, tight as a drum, and blast centralised, chilled air to keep them in a very tight envelope of temperature and humidity,” says Page.

“In that type of scenario, you’re consuming nearly as much energy keeping those servers cool as you are running the servers.

“What we discovered – in the process of owning and operating our own datacentres – is that we can use outside air and effectively open the windows to achieve the same effect,” she adds.

Location, location, location

The company typically looks for sites situated close to low-carbon power sources, as was the case with the 2010 opening of its Niagara County facility in western New York.

This location allows the company to tap into local hydropower supplies for energy, as well as the region’s temperate climate to keep cooling costs to a minimum.

The western New York site was also the first to feature a datacentre built using the Yahoo Computer Coop (YCC) design architecture, which favours ambient air over machine cooling techniques.

The datacentre is the place where we have the biggest opportunity to make an impact

Christina Page, Yahoo

“It’s a low-tech design and is cheaper to build because you’re not installing these big chiller systems inside. It’s also more reliable as there are fewer moving parts to fail,” she says.

Facilities built according to YCC specifications have a long and narrow “chicken coop-style” design, says Page, to encourage outside air to circulate inside and ensure just 1% of a building's total energy consumption is being drawn on to cool it.

“What we’ve done is sited in places where there are few enough hot and humid days of the year so this designs really works.

“At the time we were being conservative, and what we’ve concluded is that there are other locations where there are more hot and humid days that work just as well with this technology,” she says.

The western New York facility is quoted as having a power usage effectiveness (PUE) rating of 1.08, and the implementation of the YCC design resulted in Yahoo being awarded a $9.9m grant from the US Department of Energy in 2010.

Read more about green datacentres

For these reasons, Page says variations on the YCC design are starting to crop up elsewhere in the industry, as operators feel “encouraged and emboldened” by seeing a high-profile company like Yahoo do something like this.

However, there are still challenges to overcome, she says, particularly when it comes to satisfying the demand for datacentre resources in hotter climates, where the “chicken coop” design doesn’t work so well.

This has led Yahoo to experiment with oil submersion cooling techniques that see datacentre servers completely immersed in a tank of dielectric coolant that captures the heat emitted by the hardware so that it can be extracted.

“We’re continuously looking for innovations we can apply to bring about efficiencies in other parts of the world, as it’s not one-size-fits-all.

“Figuring things out that are appropriate for the location, in terms of the bottom line and energy impact, requires a bit more thinking. We’re constantly looking to address that,” says Page.

Renewable energy pledges

As previously stated, drawing on renewable energy sources to power Yahoo’s datacentres is a top priority for the company, and it has embarked on a number of initiatives to ensure supply.

These include signing a power purchase agreement with US-based OwnEnergy. It is hoped this will result in the creation of a Kansas-based wind farm that will eventually generate around 100,000MWh of power a year.

This power will be made available to the Southwest Power Pool Network, which effectively acts as a centralised repository for surplus energy that other towns can draw on if supply drops for any reason.

This approach, Yahoo claims, allows it to offset the large amounts of energy it consumes in its datacentres, while contributing to making renewable energy a more widely available resource.

“This power purchase agreement has a high degree of flexibility that allows me to commit to being a customer and to drive the development of renewable energy, while also factoring in that I may grow a lot faster,” explains Page.

“I’m also able to drive the development of renewable energy and keep it as a financial hedge so if I grow at the rate I think I’m going to grow or start going gangbusters, maybe this is energy I can use in my datacentre,” she adds. 

This kind of financial model is something Page would be keen to see more of the cloud provider community adopt to pay something back for the large amounts of energy their datacentres consume.

“I’d love to see cloud providers figure out a way to do similar deals as I think it sends out a strong message to the utilities companies about how they’d like their services to be powered.

“It’s a very exciting potential strategy for cloud companies to look at, particularly at a time when the industry is questioning how to do more to drive up adoption of renewable energy. And you know what? This might just be the way to do it,” she says.

Environmental groups such as Greenpeace are regularly drawing attention to the fact many of the datacentres used to deliver the cloud services users rely on are fuelled by non-renewable energy.

For this reason, Page says providers need to take steps to ensure they have a plan in place to use more renewable energy sources in their facilities, as it’s something customers are becoming notably more savvy about.

“Five years ago, it was harder to get that information. Now Greenpeace and others are empowering people by providing this greater level of transparency about the cloud supply chain. Cloud providers need to ask themselves, do our customers care about this? And, increasingly, they do,” she says.

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