Google tests battery backups, aims to ditch emergency datacenter diesel

Tests in Belgium might mean carbon-free backup power for its other DCs

The pilot of a new emergency battery power system at a Google datacenter in Belgium may be the first of many steps toward eliminating diesel generators from similar facilities around the world.

Google talked up the success of the datacenter battery power backup trial, which took place at its bit barn in St Ghislain, west Belgium, earlier this week alongside several other renewable energy announcements.

Altogether, the aim is to move Google further toward its goal of being entirely powered by carbon-free energy by 2030. 

There's an important distinction to make between carbon free and carbon neutral: carbon neutrality involves matching dirty energy expenditure with investment in green energy production. By that definition, Google has been carbon neutral since 2017. 

Carbon free, however, is described by Google as a "moonshot" goal, and with good reason: Being carbon free, as far as Google is concerned, means "decarboniz[ing] our electricity supply completely and operat[ing] on 24/7 carbon-free energy, everywhere, by 2030."

At the St Ghislain datacenter, Google replaced the diesel power backup system for the facility with an array of batteries. That project was launched in 2020, and now two years later Google said it's nearly up and running. 

"We have now fully installed and tested the battery and are preparing to use it to support the Belgian grid," Google said. In addition to storing energy for emergency use, Google said the battery system will also be used to load balance the local electrical grid. 

The successful test of the system also means Google may start deploying similar technology at other datacenters "across our global portfolio … this kind of technology will help us achieve our 24/7 carbon-free energy goal," Google said. 

Previous research by Omdia earlier this year suggested data centre operators could use UPS systems linked to the electricity grid to lessen any unpredictability of renewable energy resources.

Elsewhere in Google renewables

Google also reported today that three of its solar energy projects have just come online in its datacenters in Quilicura, Chile; Hamina, Finland; and Fredericia, Denmark. Each of the DCs is feeding energy into the grids in which they reside, said the tech giant. 

In Chile, a new wind farm that Google built in cooperation with power company AES Chile will take Google's first Latin American datacenter over the 80 percent carbon-free energy mark, it said. The wind energy portion of the project consists of 23 turbines and forms a part of a larger solar/wind portfolio that can generate up to 125 MW of energy.

Google recently contracted with Finland's Ilmatar power company to buy 60 percent of the 212 MW generated by its newly completed wind farm, which Google said was built in large part thanks to its own investment in the facility. Finally, in Denmark, the local Rødby Fjord solar project has begun delivering carbon-free energy that Google said will supplement existing solar power it uses in Fredericia. 

Google describes itself as an early pioneer of corporate power purchase agreements (PPAs), which are a standard contract type used by power companies and the grids they service to finance facility construction with a guarantee the facility will be used. 

In Google's case, its PPAs are intended to fund the construction of carbon-free energy facilities, which are meant to put power onto local grids that may or may not be in close proximity to the actual datacenter. The money Google continues to pay as part of its PPAs includes the bulk purchase of energy generated by renewable sources.

Technically, the carbon-free energy flowing into the local grid that Google has purchased can end up powering any one of the facilities or homes the generator is connected to. That's not an issue though, said Google, because electricity is a fungible asset: One electron is just as good as the next.

"From a physical perspective, this is just as good as consuming the renewable energy directly," Google said. ®