Rising demand forecasts are presenting significant challenges for public power utilities. A primary driver is data center interest within local communities.
According to APPA’s October 2025 report, What Public Power Needs to Know about Serving Data Centers, projections for data center capacity growth range from 50 GW (S&P Global Market Intelligence) to 120 GW (Deloitte and Lawrence Berkeley National Laboratory. At any end of that spectrum, it’s an historic amount of demand.
As you think about the issues surrounding meeting this unprecedented demand, new technologies should be a key focus for public power. A good example of this is the recent move by the Utah Municipal Power Agency to deploy 48 MW of new capacity using linear generators in Nephi, Utah.
Linear generators: One new solution worth your attention.
As I strive to keep abreast of evolving industry issues and challenges, I was fortunate about two years ago to learn of Mainspring Energy and the entirely new approach it is taking to meeting local power generation needs. Their demonstrated success, examples of which are below, is impressive.
The company manufactures Linear Generators: power generators that run on any fuel, are fully dispatchable, use no water, and emit near-zero NOx. With their proprietary technology, Mainspring delivers local power that can rapidly add new capacity and deliver reliable, affordable electric power. They began commercial shipments in 2020 and today have hundreds of megawatts in field operations and advanced development. I’ve been so impressed with their solution, in fact, that I’ve joined their Strategic Advisory Board.
A record of success with existing installations.
Most utility managers understandably don’t want to be first when it comes to adopting newer technologies. We all want the reassurance that a product is proven in customer field operations. Fortunately, there are multiple existing installations of linear generators up and running. I’ve visited some myself. Here are two installations I think you’ll find especially relevant.
An irrigation district powering one of the fastest growing cities in the U.S.
Lathrop Irrigation District (LID) is the municipal electric utility serving the River Islands community in Lathrop, CA — one of the fastest growing cities in the U.S. LID needed power to support approximately 4,000 homes and 3 million square feet of commercial space.
Their ideal power solution would help lower electricity costs, quickly dispatch to complement existing rooftop solar, and meet the NOx emissions compliance with the San Joaquin Valley Air Pollution Control District, one of the strictest in the country. What’s more, it had to fit in a limited footprint, scale with long-term community growth, and be deployed and permitted quickly to keep pace with development.
Mainspring’s low-emissions design and factory-built units enabled LID to secure air permits in three months and deploy 2.3 MW generators in seven months.
Commercially operational since February, 2025, LID is now meeting 95% of River Island’s peak demand, has 24/7 control over its electricity supply reducing its exposure to volatile pricing and rising transmission costs, and with Mainspring’s modular design, is well positioned for future capacity expansion.
10MW of new electricity without three years of grid infrastructure buildout.
Facing California’s ambitious zero-emissions truck mandate with properties near the Los Angeles and Long Beach ports, logistics real estate company Prologis needed to deploy EV charging infrastructure for its customer, Maersk, looking to charge a fleet of up to 96 electric drayage trucks.
This would require nearly 10 MW of capacity and take three years of grid infrastructure build-out.
Grid resilience and cost also presented longer-term challenges, as did the need to meet the company’s own ambitious sustainability goals. The new EV charging infrastructure needed to be fast, resilient, cost-effective, and clean.
Prologis reduced that estimated time for new power from nearly 36 months down to 9 months with a power solution consisting of 3 MW of Mainspring Linear Generators and 6 MW / 18 MWh of storage.
Commercially operational since 2024, Prologis has eliminated outage risk with an islanded microgrid, obtained best-in-class total cost of ownership resulting from competitive capital costs and low operating expenses, and has the ability to run biogas and zero-carbon fuels like hydrogen as well as natural gas. It’s the largest EV truck charging station in North America.
An opportunity to learn more through APPA
If this piques your interest, Mainspring will be participating in the APPA Engineering and Operations Conference, March 29 - April 1, 2026 and the annual APPA conference in June. Either would be a good place for public power managers and their staff to learn more about how linear generator technology can help meet the significant demand challenges facing today’s public power utilities.
