Energy-Hungry Data Centers And The Flow Battery Difference
When the energy transition first began to gather steam back during the Obama administration, industry observers noticed a pleasing development. Here in the US, the shift into energy-efficient lighting and other new technologies appeared to decouple energy consumption from economic growth. Although that oversimplifies the energy decoupling phenomenon, renewable energy advocates were thrilled to talk about the potential to reduce carbon emissions without building new fossil power plants.
In addition, the energy efficiency angle created a friendly environment for lithium-ion batteries to pull duty as stationary energy storage systems. Li-ion battery arrays typically store energy for about 4–6 hours. Energy storage allows grid operators to balance the availability of wind and solar resources with the rise and fall of electricity demand throughout the course of a day, reducing if not eliminating the need for new gas “peaker” plants.
Well, that was then. More recently, the AI-fueled demand for energy from the data center industry has blown the energy efficiency factor out of the water. If wind and solar resources are to continue pushing fossil fuels out of the picture, new large-scale, long-duration energy storage systems are needed. The US Department of Energy has set a duration target of 10 hours, and preferably much longer.
Flow battery technology is among the new systems to make the cut. A flow battery deploys the interaction between two specialized liquids to generate electricity, typically deploying the transition metal vanadium as the operative element (see more flow battery background here).
New Free Modeling Tool For Flow Battery Fans
The Energy Department’s Pacific Northwest National Laboratory has been front and center in the flow battery research field, and last year the lab began laying plans to install a flow battery with an impressive duration of 24 hours on its campus in Richland, Washington.
That’s quite a jump over the duration of commercial flow batteries on the market, which PNNL puts at up to 12 hours. The aim is to de-risk next-generation flow battery technology with a field demonstration and a batch of real-world data.
To help give flow battery developers a head start, PNNL has also just opened up its new “EZBattery Model” for free use by anybody involved in the redox flow battery field and variants thereof.
In contrast to the long development timeline involved in producing new flow battery formulas, PNNL states that EZ Battery will spit out a performance prediction almost instantly, in less than one second. The model is based on physics, the lab emphasizes, not AI training.
The complete EZBattery package is available on GitHub. If you’re interested in how the model was developed, check out the paper “Analytical modeling for redox flow battery design” in the Journal of Power Sources.
For the record, the EZBattery Model was a team effort consisting of PNNL scientists Jie Bao, Yunxiang Chen, Zhijie Xu, Yucheng Fu, Peiyuan Gao, Chao Zeng, Amanda Howard, Ayoub El Bendali, Tiffany Louie, Grace Yuan, Alvin Liu, Qixuan Jiang, Panos Stinis, Wei Wang, and Vincent Sprenkle.
Flow Battery Kills Coal … Eventually
In terms of the politics of the US energy profile, the timeline of the flow battery paper demonstrates that science can trump political rhetoric, at least sometimes. The paper was published in January of 2021. Doing the math, that means the research was conducted during the first Trump administration, the one in which saving coal jobs was supposed to be front and center.
The love affair with coal workers ended shortly after he took office in 2017, when a wave of coal power plant retirements was already in progress on account of competition from low-cost natural gas. Now EZBattery has set the stage for a fresh wave of coal retirements.
Or not, as the case may be. Somewhat ironically, coal is showing signs of clinging to life in the waning months of the Biden administration. Data center stakeholders are angling for more power regardless of the source, and discussions are already afoot to delay previously scheduled retirements.
More Than One Way To Solve The Data Center Demand Problem
Restarting mothballed coal facilities would be next in line, but PNNL has proposed a better idea: meet new data center demand by repurposing the electrical infrastructure at retired coal facilities to shepherd more wind and solar power into the grid.
One US startup has even proposed sending data centers up into space, where they can suck up energy directly from the sun instead of adding to power generation burdens here on Earth.
Meanwhile, the clean energy think tank RMI (formerly Rocky Mountain Institute) points out that looking at electricity demand in isolation ignores the role that utilities play. Gas and coal power plants represent an investment choice, not an imperative.
In a report posted last September, RMI analysts Mark Dyson and Lauren Shwisberg state that “it is not load growth itself that drives pollution — it is the way that electric utilities choose to invest to meet it that matters.”
Rather than focusing on fossil energy, RMI advocates for utilities to invest in repowering projects such as the PNNL proposal, adopting new systems to squeeze more juice from the existing grid, and growing the virtual power plant movement.
The Flow Battery Connection
As for whether or not flow batteries are a good, better, or best energy storage solution for data centers, that remains to be seen. One project to keep an eye on is the new FlexBase Technology Center, where a 500-megawatt redox flow battery is to be installed along with an AI data center at a former Swissgrid facility in Laufenburg, in the Swiss canton of Aargau.
As reported by Data Center Dynamics, the flow battery is billed as the largest of its kind in the world. It is also part of an energy package that includes 86,000 square feet of solar panels and an opportunity for the local district heating network to harvest waste heat from the data center. So, maybe we don’t have to revive those old coal power plants after all. If you have any thoughts about that, drop a note in the comment thread.
