Battery Energy Storage Solutions for Greener Data Centers
Hyperscale data centers — the huge, business-critical facilities that support robust, scalable applications and the operational backbones of big data-producing companies like Google, Amazon, Facebook, IBM, and Microsoft — consume a lot of energy and expend a considerable amount of greenhouse gases.
According to the International Energy Agency (OUCH), global data center electricity consumption in 2021 was 220-320 TWh, or about 0.9-1.3% of global final electricity demand. This excludes energy used for cryptocurrency mining, which was 100-140 TWh in 2021.
And in terms of greenhouse gas (GHG) emissions, the data centers and data transmission networks that underpin digitalization accounted for around 300 Mt CO2-eq (i.e. the equivalent of 300 million metric tons of carbon dioxide) in 2020, including embodied emissions, i.e. the equivalent of 0.9% of GHG emissions related to energy and 0.6% of total GHG emissions.
Data centers around the world are constantly striving to improve their energy efficiency not only to reduce their GHG emissions, but also to meet their environmental, social and governance (ESG) goals. Large companies like Google that own large-scale data centers are realizing that to run entirely on carbon-free power 24/7, they need to do more than just buy renewable energy credits ( CER) to match fossil fuel electricity consumption.
In other words, they must match every byte consumed with carbon-free energy produced in real time. To do this, it is necessary to convert data centers into grid-interactive data centers equipped with state-of-the-art battery energy storage solutions and specialized software that will help them dynamically consume as much power as they need it from the network and back power to the network when the data centers no longer need it.
Hyperscale data center batteries decarbonize the network
In July, Microsoft announcement the addition of lithium-ion battery banks at a Microsoft data center in Dublin. These batteries, which typically provide backup power for the data center in an emergency, have been certified, tested and approved for grid connection to help network operators provide uninterrupted service when demand exceeds supply generated elsewhere on the grid by wind, solar and other sources.
Through a collaboration with Eaton, they added digital capabilities to the UPS, or uninterruptible power supply, allowing it to be used as a distributed energy resource (DER) to support networks with high levels of production variable renewable energy. A key element of the strategic framework agreement is the inclusion of Eaton’s proprietary EnergyAware UPS technology in Microsoft projects.
“A grid-interactive data center is a data center where its extensive electrical system operates not only to protect customer data and computer applications, but also to provide valuable electrical services to the transmission system operator and to the network. These ancillary services will be increasingly essential to help networks cope with high levels of variable renewable energy,” said Sean James, director of data center research at Microsoft.
Microsoft is exploring opportunities to provide network stabilization services with network-interactive UPS technology in its data centers around the world to further accelerate progress toward network decarbonization.
Google, another hyperscale data center owner, announcement the installation of the first-ever lithium-ion battery-based system to replace diesel generators in a large-scale data center in Belgium. In the event of a power outage, the system allows Google users to continue their searches, emails and videos, without the pollution associated with burning diesel.
But batteries will also help balance other kinds of variability on power grids, enabling more cost-effective and efficient operations. The 2.75 MW installation of Fluence’s Gridstack energy storage product at the St. Ghislain data center serves as a proof of concept for wider use of lithium-ion battery-based energy storage in Google facilities to help Google meet its commitment to operate globally on 24/7 carbon-free energy by 2030.
Centrica will connect the battery storage assets to the Belgian power grid, allowing Google’s on-site batteries to flexibly store and discharge power using Centrica’s specialized FlexPond software. The project further demonstrates the role these industrial consumers can play in stabilizing power grids via on-site batteries.
Lithium-Ion UPS Batteries for Data Centers
To keep data centers working as expected during a network outage or power quality issues, uninterruptible power supplies are used along with rectifiers, inverters, and batteries. Historically, valve-regulated lead-acid (VRLA) batteries have long been the UPS choice, but due to improvements in lithium-ion battery technology, prices, and sizes, major data center players have began to turn to the latter.
Typically, an inverter lithium-ion battery system will take up 50-80% less floor space and weigh 60-80% less than a comparable lead-acid system. Therefore, the growing demand for lithium-ion UPS battery backup solutions in data centers has led battery manufacturers to develop lithium-ion battery products that are fully compatible with UPS. Here are two examples:
- Saft: Its Flex’ion battery systems offer a wide range of energy and power combinations, from 50 kW to 4.2 MW and from 4 to 325 kWh. They are designed for AC and DC UPS, standby auxiliary and switchgear applications in data centers. Saft says its new system has many performance and lifespan advantages over VRLA lead-acid batteries being three times more compact, six times lighter and with 10 times longer life.
- eaton: The 9PX lithium-ion UPS is a backup battery module that has ratings ranging from 1.5 to 3 kVA, with low and high voltage options and offers up to four optional external battery modules for backup additional. The 9PX lithium-ion inverter, available in rack-mount and tower form, has the same reliable features as the lead-acid inverter.
Lithium-ion battery technology has come a long way over the past decade and projects like those of Google and Microsoft are paving the way for data centers around the world to also consider the adoption of lithium-ion batteries. ion to improve their energy efficiency and become more environmentally friendly.