AI Data Centers: Driving Battery Technologies That Could Be Useful Beyond Powering Servers
Reviving interest in organic flow batteries for safe, scalable energy storage beyond lithium-ion risks.
If you have been paying attention to almost anything regarding the grid, electricity, consumption, or in general not living under a rock, you know that the growth of data centers, in particular artificial intelligence (AI) data centers, has sparked a huge increase in the demand for electricity. In fact, The Fusion Report ran an article about the increased demand from datacenters, and the impact on the power grid, in February. In that article, we highlighted that data centers are expected to make up between 6.7% and 12% of US electricity consumption by 2028, continuing a historical trend shown in the adjacent illustration. In places like Virginia, data centers consume roughly one-fourth of all of the state’s electricity.
While more electrical power is clearly the long-term solution, it doesn’t help the situation today. The challenge with AI datacenters is that there are no particular “peak hours”, when power consumption is higher than other times. This means that there is not a way to “plan around” the electricity needs of a datacenter. It also means that data centers are adding considerably to electrical demand during peak hours. At best, power can be stored during super-off-peak electricity hours, and then used to power the data centers during peak hours. However, the use of lithium-ion batteries in datacenters is highly undesirable because of their flammability, which is why datacenter operators are showing more interest in developing and using new battery energy storage technologies to improve the situation.
An “Old” Technology Back Again – Organic Flow Batteries
Sometimes the solution to new problems lies in (relatively) old technologies used in new ways. An example of this is “organic flow batteries”. In organic flow batteries, two liquid electrolytes are stored in separate tanks, where the power is stored in a chemical form. During the charging of an organic flow battery, the two liquids are pumped through a “central stack”, where one liquid is oxidized (loses electrons) while the other liquid is reduced (gains electrons) due to the voltage differential across the central stack. During discharge, the reverse happens.
The historic drawback of flow batteries has been their relatively low power density relative to batteries such as lithium-ion, which have very high energy density. While energy density is very important for electric vehicles, it is a much less important issue for grid-scale energy storage systems. Moreover, because these flow batteries use organic molecules, the environmental impact is significantly less than metal-based batteries like lead-acid batteries or lithium-ion batteries, and the cost for organic flow batteries is much lower. Additionally, battery attributes such as voltage and solubility can be “customized” by varying the organic compounds used in the battery. Finally, these batteries are not susceptible to battery fires like lithium-ion batteries are, an important characteristic for data centers.
A number of companies are working on developing flow batteries, including both startups and established battery companies. One of the most interesting characteristics of organic flow batteries is that they are highly scalable, from cargo container-size systems to vast tank farms. The illustration above is from XL Batteries, who is building a 333 kilowatt (kW) demonstration-scale organic flow battery for Prometheus Hyperscale data centers in Wyoming. Assuming the demonstration-scale system is successful, Prometheus will purchase 12.5 megawatt (MW)/125 megawatt-hour (MWh) systems starting in 2028.
Other Potential Uses of Organic Flow Batteries
Utilities are also looking at organic flow batteries, both for energy storage at renewable power sites such as solar and wind farms, and near urban areas. The primary draw to these batteries for grid-scale utility customers is that they avoid the “battery fire” issues that have plagued energy storage facilities based on lithium-ion batteries. A notable battery fire at Vistra Energy’s Moss Landing battery storage facility is but one example of this issue. These fires, which are essentially impossible to put out, have negatively impacted the deployment of battery storage systems in a number of US municipalities, a situation that organic flow batteries will avoid.
