Under the microscope: Different datacentre sustainability strategies

Less Heat to Cool

Efficiency begins with facility design, taking into account both the servers that power the internet and the equipment that supports them.  Inefficient equipment both wastes electricity and produces excess heat that needs to be cooled, resulting in the consumption of even more electricity or large amounts of water.

By understanding this double-impact, there are a number of low-cost, effective improvements that can minimize energy and water consumption through eliminating both wasted power and heat.  While selecting efficient servers is crucial for datacentres as a whole, since CyrusOne is a colocation provider, I’m just going to focus on the data support equipment that pays this double dividend.

• High-efficiency uninterruptible power supplies (UPS): These UPSs generate little waste heat and operate efficiently even while running at 50% maximum capacity, so the datacentre doesn’t have to be at full capacity for peak efficiency.
• Ultrasonic humidification: Instead of using heat or pressurised water to produce water vapor for humidification, ultrasonic humidification systems maintain the necessary humidity using only 7% of the energy of more traditional electric steam humidifiers, all without adding heat to the data hall.
• LED lighting: Older lighting technology converts more of its electricity into heat than into light, but modern LED lighting gives operators the double dividend of less data hall heat and less wasted electricity. Coupled with occupancy sensors, LEDs deliver lighting only where and when it is needed.

Right cooling, right time, right place

Because data halls, especially for colocation providers, often host a variety of different servers, they must be built to be flexible and remain efficient at a wide range of occupancy.  Older cooling technologies had to run at full capacity regardless of the actual need for cooling, resulting in overproduction and waste.

Modern datacentres can use a variety of technologies to deliver the right cooling to the right place at the right time regardless of current occupancy.  Those technologies include:

• Building management systems: Using intelligent systems and sensor networks, the datacentre predicts the need for cooling and adjusts chiller output, air handling, and other factors to meet customer needs with minimal electricity use.
• Economizers: Also called “free cooling” systems, these use low outdoor ambient air temperatures to generate chilling when the weather is right, using roughly 1/7 of the electricity required by standard chillers. Economizers are installed in facilities where the local climate provides efficient free cooling.
• High-efficiency chillers: The air-cooled chillers that we source are selected for efficiency, flexibility, and reliability. We design for water-free cooling from the ground-up, maximizing the efficiency of our systems and avoiding dependence on water. Water is used in only a closed loop system to remove heat from the data hall, but no water is consumed in the process.
• Throttling: Newer systems use controllable variable frequency drives (VFDs) to power air handler fans and pumps, meaning they don’t have to be “all on” or “all off.” The cooling distribution equipment is operated at just the right level needed for optimal cooling without wasting energy.
• Liquid-to-chip cooling: This system allows even higher efficiency for customers who want to use various liquid cooling methods (in-row cooling, liquid-to-cabinet, liquid-to-chip, and immersion cooling).
• Airflow Modeling: We use Computational Fluid Dynamics (CFD) to model the flow of chilled air through our data hall and the equipment it needs to cool.  While this is sometimes done during initial design, by updating our model with actual conditions in the data hall, we can make adjustments to deliver just the right amount of chilled air to the equipment.

Make mine renewable

Making the switch to renewable energy is and will continue to be a key datacentre sustainability strategy. As “green” power costs come into alignment with “brown”, the barriers to carbon-neutral energy are evaporating.  As an additional benefit, since most green power generation doesn’t consume water the way fossil fuel generation does, we have the opportunity to make both our electrical generation and our onsite cooling water-free.

One of the hurdles that remains for organisations to increase their renewable procurement comes in the form of energy contract terms.  Many companies purchase brown power with short term agreements of a year or less, whereas many of the available green power projects that result in additional power require much longer commitments – sometimes as long as 10 years or more.

Such agreements can expose organisations to market volatility they may be unfamiliar or uncomfortable with.  As the renewables market continues to mature and energy buyers gain experience with renewable power, we will find strategies such as forming groups like the Renewable Energy Buyers Alliance (REBA) to overcome these hurdles.

Why not skip the efficiency measures above and just go straight to renewable power?  We still have to be good citizens of the grid and give our customers good value. Efficiency lets us reduce strain on the grid and expenses for our customers, while also freeing up renewable power for other industries.  Think of it as the energy form of reduce, reuse, recycle.

Don’t Forget Water and Biodiversity

Because the threat of climate change looms large, many companies’ main target right now is to reduce carbon. One way some accomplish this is to shift their cooling burden from consuming electricity to consuming water.

While consuming water can reduce carbon from some kinds of electricity (like fossil fuel generation), in many regions this is trading one problem for another.  Datacentre companies also need to consider local impacts to water stress when evaluating sites and their cooling technologies.

The old wisdom was that generating electricity necessarily consumed large amounts of water, so any water consumed onsite for cooling would be balanced by savings at the electrical plant.

However, with the shift to renewable power generation, which is largely water-free, that old assumption no longer holds, leaving facilities with a big onsite water footprint that could have been avoided. This may be acceptable in locations where water supplies are plentiful, but can cause problems if water becomes scarce, as is predicted by climate change models for many locations.  To ignore this water risk is bad for the region and for the data centers’ operational continuity.

Another often-neglected consideration is biodiversity and habitat preservation.  While climate disruption affects habitat and conserving water has big local benefits for biodiversity of a region, there’s no avoiding that datacentre footprints (or any buildings for that matter) can locally displace plant and animal habitat.  This can be mitigated in a few different ways.

One way is through looking at landscaping as an opportunity for good, rather than just covering up undeveloped land.  We all want to work in a pleasing environment and landscaping helps create this feel but, let’s face it…traditional datacentres closely resemble bomb shelters — not the most aesthetically pleasing!

Rather than trying to make our surrounding landscape look like golf greens, we can take the opportunity to create improved wildlife habitats by selecting plants and features to provide food, water, shelter, nesting sites, and other necessities. Furthermore, by favoring native or climate-adapted plants you can often achieve water savings as well as biodiversity goals, while reducing landscaping costs from replanting and other maintenance.

Another way to mitigate habitat loss and improve local habitat is through looking beyond your property line.  By working with local partners there are many ways that you can contribute to your local community’s restoration efforts, creating habitat for animals and recreation for neighbors through volunteer time and sponsorship.

While our team at CyrusOne doesn’t claim to have all of the answers on sustainability, our newly released Sustainability Report details our specific efforts and shows measurable results that confirm our commitment to being climate neutral by 2040.

We see our sustainability efforts as a long journey. As I tried to share in this article, there’s no one solution.  But by carefully thinking about our designs, operations, and place in the community we can contribute to societal good through more ways than just keeping the internet running.