Small But Mighty: Small-Scale Battery Storage Saves the Day

Feb 24, 2025 | Txses Impact

By Elle Nicholson

Battery energy storage systems, commonly referred to as BESS, have quickly become an invaluable tool in the energy industry, for both utilities and small-scale applications alike. The systems work by drawing energy from the grid (or a localized power source), storing the charge, and later releasing it to provide electricity or other grid services as needed.¹ Typically, BESS charge when energy is cheap and demand is low, and then discharge the stored energy when demand and prices are higher.² At the residential level, BESS connect to the homeowner’s distribution system, drawing energy from solar panels interconnected to the system. This allows homeowners to control when excess solar energy is sent back to the power grid or to store it for when the home’s demand is highest.

The ability to “island” a home in this manner provides increased resiliency for homeowners during instances of grid failure.³ For example, during last summer’s Hurricane Beryl, thousands of Houston residents who had previously installed a combination of solar panels and battery storage were able to take advantage of their BESS technology to retain electrical power throughout the course of the citywide outage.⁴ Many were even able to use extension cords to power several of their neighbors’ basic appliances, demonstrating the resiliency that BESS can bring to neighborhoods.⁵

Similarly, BESS can improve grid resiliency, as evidenced during 2021’s Winter Storm Uri. Bandera Electric Cooperative, a cooperative located in the Texas Hill Country, has been a pioneer of BESS for several years. During the storm, the cooperative signaled its battery users to discharge their stored energy,⁶ powering parts of the community while reducing pressure on backup generators.⁷ The procedure ended up saving Bandera around $43,000, showing the important role BESS can play in grid resiliency.

BESS also can deliver financial benefits, depending on whether a customer’s utility allows such options. The technology can perform peak shaving and load shifting to lower homeowners’ electric bills by discharging when demand and costs are high.⁸ Doing so helps users avoid the high costs associated with peak usage times while ensuring more energy is available throughout the distribution grid, thus lowering costs for all utility clients. This has the added benefit of reducing grid strain, especially during the hottest days of summer. Additionally, homeowners can potentially sell excess energy from BESS in the state’s pilot aggregate distributed energy resource (ADER) program. The program, currently capped at 80MW, relies on battery storage as a core component.⁹ It uses an automated response system to follow ERCOT instructions, allowing participating customers to sell surplus power to the grid upon signal. However, for an individual to take part in the ADER, their utility must already be a participant.

When compared to traditional backup generators, battery storage systems have higher upfront costs but save more money in the long run. A previous report from Texas Solar Energy Society comparing the costs of solar and storage with traditional generators found that solar storage systems’ upfront costs fall within the $8,500-$10,000 per unit range.¹⁰ Generators range from $1,000-$7,000 per unit, making them initially cheaper, but they have higher operational costs due to refueling and maintenance requirements. An average propane generator would cost $20,000 in fuel and $1,000 in maintenance over a ten-year period.¹¹ In comparison, a lithium-ion residential BESS costs about $50 per kW annually to operate and maintain.¹² For a Tesla Powerwall, this would equate to around $6,800 over a ten-year period, saving consumers a substantial amount of money. Moreover, since BESS facilitates consumption of solar energy in lieu of grid electricity, customers enjoy reduced utility bills. Thus, homeowners pay more in the long run for generators than they do for batteries despite the difference in upfront costs.

The resilience and financial benefits of BESS have made them an appealing option for solar customers across Texas, and the energy industry has been rapidly expanding their battery offerings with numerous brands to choose from. Solar installers have also expanded their service offerings so that customers can use the same installer for BESS that they selected for their solar installation. In conclusion, due to its benefits and the variety of options available, battery storage has become one of the energy industry’s most exciting innovations.

References

1. Bowen, Thomas, et al. (2019, September). Grid-Scale Battery Storage Frequently Asked Questions. National Renewable Energy Laboratory. ↩︎
2. Exro Technologies. (2025). Load Shifting: What Is It and How Does It Work? Exro Technologies. ↩︎
3. Fields, Spencer. (2023, December 6). Utility-Scale Battery Storage: What You Need to Know. EnergySage. ↩︎
4. Bechtold, Ryan. (2024, July 25). Sunnova Solar + Storage Systems Powered Nearly 3,000 Customers Through Hurricane Beryl. Sunnova News. ↩︎
5. Young, Jeff. (2024, July 12). Hurricane Beryl Hit His Home. Solar Power Kept His Lights on. Newsweek. ↩︎
6. National Rural Electric Cooperative Association. (2023, February). Battery Energy Storage Update: Utility Residential and Long Duration Use Case Studies. National Rural Electric Cooperative Association. ↩︎
7. Elgqvist, Emma. (2021, June). Battery Storage for Resilience. National Renewable Energy Laboratory. ↩︎
8. Lightsource BP. (2025). Battery Energy Storage Systems (BESS) 101. Lightsource BP. ↩︎
9. Public Utility Commission of Texas. (2023, August 23). ‘Virtual Power Plants’ to Provide Power to ERCOT Grid for the First Time. Public Utility Commission of Texas. ↩︎
10. Alkhatib, Mohammad. (2024, August 9). Solar + Storage vs. Generators in the United States. Texas Solar Energy Society. ↩︎
11. Pane, Mike. (2019, December 18). Comparing 10 Year Ownership Costs of Battery Storage and an Auto Start Generator. Synergy Solar. ↩︎
12. Statista. (2023, October 9). Installed Cost and Annual Operation and Maintenance Costs of Energy Storage Technologies. Statista. ↩︎