How Battery Energy Storage System Testing Is Making the Grid More Sustainable

U.S. energy needs have changed dramatically over the last few decades, and questions are growing as to whether our grid can manage these new demands. Aside from rising temperatures—the National Oceanic and Atmospheric Administration declared 2023 the hottest year on record—the energy sector is managing a trio of additional challenges:

• City populations are growing, creating a greater need in already crowded areas and forcing the expansion of power grids further from the city center.
• Artificial intelligence (AI)-powered technologies, now integrated into some of the world’s most popular applications, require greater computing power. A Goldman Sachs report found ChatGPT queries require 10 times as much power as a Google search, and it expects data center power demand will increase by 160% by 2030.
• As more drivers switch to electric vehicles and hybrids, there will be a need for more charging power in residential neighborhoods, within commercial developments, and along interstates and highways.

Any one of these developments would warrant an upgrade to our national grid. Taken together, they’re a warning that action needs to be taken quickly. The grid must be prepared to meet heavier demand for longer periods of time, and it must be resilient against unexpected, long-duration outages.

Clean, renewable solutions are waiting in the wings, but the energy sector must address grid deficiencies first. The grid was designed for the consistent baseload power generation provided by fossil fuels and is not ready to integrate intermittent sources such as wind and solar at scale. As pressure increases to harness these renewable energies, new technology will be needed to ensure the grid can accommodate renewables and maintain a balanced power supply and demand.

One promising option: battery energy storage systems (BESSs), designed to hold in reserve excess wind and solar output and distribute it to the grid when needed. BESS manufacturers are deep into testing the technology across chemistries, such as advanced lead, lithium, and vanadium, putting each through real-world paces to demonstrate its viability. Early results suggest BESS technology could be the backup the grid needs to meet accelerating demand.

Here’s an update on the state of BESS testing, what a real-life vanadium BESS test outside Atlanta looks like, and how initial findings are guiding use cases to further research.

The Current Focus in BESS Testing

BESS technology offers high hopes for ongoing grid support, and manufacturers are exploring ways to make the solutions viable on a larger scale. They’re looking to reduce concerns around the time and money needed to deliver a system, meet a price point the customer can tolerate, and ensure the technology can deliver optimal performance no matter the environment where it’s installed. That’s why much of today’s testing focuses on two areas: enhancing reliability and cost-cutting measures.

From a reliability perspective, BESS manufacturers are putting battery stacks through their paces. Resiliency testing doesn’t require manufacturers to build a full-scale system with hundreds of megawatts of power, making it easier to test more modest kilowatt-scale demonstration systems to capture the key learnings. Researchers are constantly cycling these demonstration systems to prove these batteries are safe, can meet challenging response time requirements, hold up when cycled in both very hot and cold periods, and maintain their capacity and performance over years to decades of use. Each passing day that the batteries cycle is another day demonstrating the technology’s real-world viability.

In parallel, BESS manufacturers must continue to drive down costs to meet market pricing expectations. Cost savings will come from the economies of scale of large-volume production, as well as continued innovation in designs and manufacturing methods.

The Department of Energy has invested significant dollars to support the rapid scaling of domestic manufacturing capacity. At the same time, companies like Stryten Energy are investigating new system architectures that better support cost-effective BESS deployments for utility-scale systems. The next-generation vanadium redox flow battery (VRFB) systems may look more like a traditional building-based power plant than the simple stacks of shipping containers that have represented the typical deployments today. While the new architectures offer significant cost savings, it will be important to maintain their benefits demonstrated in the smaller, demonstration-scale systems.

What Vanadium BESS Testing Looks Like in Practice

Beyond laboratory testing, many battery manufacturers are now taking their technology into the field, partnering with a utility provider to better understand the battery’s capabilities under real-world pressures. Stryten Energy recently celebrated the first anniversary of its own battery test—the first VRFB energy storage system manufactured and installed in Georgia.

The company is working with Snapping Shoals Electric Membership Corporation (SSEMC), a consumer-owned, non-profit cooperative utility provider in one of the nation’s fastest-growing areas, to demonstrate a VRFB’s storage capabilities and evaluate additional use cases—such as energy cost control, peak shaving, and avoiding curtailment (Figure 1). When properly maintained, a VRFB can operate for more than 20 years without the electrolyte losing energy storage capacity, offering an ongoing solution for long-duration energy storage of six or more hours. Additionally, domestic manufacturers can use the already-proven supply chain for building and recycling lead batteries as a blueprint for developing VRFBs, reducing the U.S.’s dependence on overseas manufacturers.

Since the initial commissioning and stabilization period, Stryten Energy and SSEMC have been working together on component and performance testing, with the first set of tests completed in April 2024. The team ran the system through four tests: baseline performance, a solar test schedule, summer and winter peak shifting to understand how the battery could help reduce grid demand during the highest and lowest temperatures of the year, and self-discharge to ensure the battery has minimal energy loss when idle. While the initial testing analysis is still on-going, SSEMC has already noted that the BESS offers very high dispatchability and resiliency.

What’s Next in VRFB Testing?

Over the coming months, Stryten Energy will be installing new upgrades to maximize reliability, as well as putting the battery through a second round of testing in real-world scenarios. Findings from the first year with SSEMC suggest further testing will be valuable for three key use cases that energy storage manufacturers across the country should be looking into as well:

• Cost Control in the Face of Changing Temperatures. EMCs are facing an increased challenge to accurately project how much power they need to buy to meet their customers’ volatile demand on a large number of very hot and very cold days experienced in recent years. During extreme cold days, the utility may have to make up for unexpected shortfalls by purchasing extra power on the real-time markets during times when real-time prices tend to spike significantly. BESS could help save the utility and its customers millions of dollars by providing a buffer of stored energy to cover the shortfalls, using energy purchased days in advance of the cold spell at more attractive pricing.
• Load Shaping During Generator Maintenance. During the spring and fall, energy generators often take their systems offline to complete maintenance. During this downtime, capacity is reduced, and utility providers must find a way to meet demand with a suboptimal energy resource mix. Having access to a BESS reserve gives utility providers more options to cover these gaps.
• Renewables Integration. A renewable energy source doesn’t always live up to its promised generation capabilities—for example, solar and wind assets are often curtailed because a significant portion of the electricity simply isn’t needed when the energy is produced. A BESS can help manage these intermittency issues and give utility providers the storage needed to fully capitalize on wind/solar generation.

Stryten Energy is already moving forward with this type of real-world testing to measure and improve how the VRFB operates in each scenario. The company is encouraged to see its peers across the industry conducting their own testing so that the U.S. energy storage market is prepared to meet today’s challenges to our grids.

Many Pathways, One Goal

BESS manufacturers have made significant headway toward proving the technology’s grid support capabilities. In addition to ongoing vanadium tests, BESSs powered by chemistries such as lithium and advanced lead are now in testing (Figure 2).

Lead, in particular, is a good fit in applications such as community resiliency centers, to help reduce demand charges for commercial businesses, and to provide cost-effective electric vehicle charging stations on demand, even during periods of the day when grid prices are high. The chemistry’s strong safety and domestic supply chain also offers a roadmap for how to produce vanadium energy storage technology at scale in the U.S.

No matter the chemistry, it’s important that BESS developers stay the course and demonstrate just how important these batteries will be in our long-term grid revitalization. Tests such as Snapping Shoals will be strong proof-of-concept that the marketplace needs to begin adopting the technology.

—Scott Childers is vice president of Essential Power at Stryten Energy.