The final frontier for data center carbon neutrality

We’ve crystalized carbon and hid it away in concrete. Entire hyperscale data centers are powered by the wind and the sun. Air, free and abundant, can be used in lieu of water to cool data centers — even in a place like Houston (which is saying a lot based on the summer we’re having in Texas).

Efficiency gains have helped to limit electricity demand from data centers to the point where they now account for only 1% of global electricity demand after data consumption shot up by almost 40% in the spring of 2020.

Still, the industry continues to challenge itself to do better by the environment, striving to reach the zero carbon holy grail. The final frontier in the fight to get that last bit of operating emissions out of the atmosphere is the uninterruptible power supply system.

Diesel engine generators have been the go-to since the beginning of data center time. They pack a lot of power into a relatively small footprint. If the fuel’s available, then a data center can stay up and running through a really long power outage.

Of course, what diesel power generators offer in terms of practicality is offset by carbon emissions. And so, data center developers and operators are bringing a lot of creative options to the table, approaching the problem from a number of angles.

Green backup power

Hyperscalers, like Facebook and Google, have rolled out interesting alternatives in recent years, and Compass announced our newest effort to go green earlier in the summer. Here’s a quick rundown on some promising front-runner alternatives to diesel-powered generators.

• Alternative fuels — Earlier this summer, Compass announced a partnership with Foster Fuels to become one of the first data center providers to use hydrogenated vegetable oil (HVO)-based biodiesel to fuel on-site generators. Using HVO blended fuels has the potential to reduce a facility’s greenhouse gas (GHG) emissions by approximately 85% versus traditional diesel. It also significantly reduces particulates and sulfides emitted.
• Lithium-ion batteries — In 2014, Facebook began testing lithium-ion (Li-ion) batteries for backup power.  As the Li-ion batteries have become increasingly available and affordable, several data center operators have begun placing them on individual racks, bypassing the traditional valve-regulated lead-acid battery UPS for backup power. Given the longer life, smaller footprint, and environmental advantages, Li-ion batteries now account for 15% of the data center battery market, and adoption is expected to reach 38.5% by 2025.  However, fire protection concerns loom large with Li-ion solutions.
• Google’s battery park - Google just completed a two-year test of a “battery park” at a data center in Belgium. The battery park replaced diesel-powered generators with 10,665 solar panels that generate a total of 2.9GWh of electricity, 5.5 MWh of which can be stored. When not in use, the battery park feeds power back into the Belgian grid.   

The reliability of a data center is everything, and it hinges on backup power. It stands to reason this is a complex issue with a lot of different solutions bubbling up to the surface.

Operators are hard at work to strike the balance between reliability and sustainability. The entire industry is taking carbon emissions very seriously, working hard and working together to design solutions that are scalable and effective. Time will tell where we land on the voyage, but the great work underway tells me progress is being made, and, ultimately, we’ll get there together.