A network of home batteries installed across thousands of Vermont residences has emerged as the state's largest source of electricity, according to reporting by the BBC. The system, operated by Green Mountain Power (GMP), functions as a virtual power plant that aggregates distributed energy resources to supply electricity during peak demand and outages.

The initiative began as a response to frequent power disruptions in rural communities. In 2024, Pollyanna Bladyka of Springfield, a town in eastern Vermont, abandoned plans to purchase a gas generator after learning about GMP's battery lease program. The utility offers two home batteries for $55 monthly over a 10-year term, a cost significantly lower than the $12,000 generator she had considered. Since installation, her household has experienced no power interruptions.

Bladyka described her motivation as self-interested rather than environmental: "I'd like to say I did it for the environment, but I did it for myself. But I don't mind helping." Her experience reflects a broader trend; over 5,500 Vermont residents now participate in the program, with enrollment accelerating after state regulators removed enrollment caps in 2023. GMP serves approximately 75% of the state's electricity customers.

The virtual power plant model aggregates residential batteries, rooftop solar panels, electric vehicle batteries, and smart devices into a coordinated network. GMP can dispatch stored energy from these systems during grid stress, reducing reliance on fossil fuel-powered peaker plants. According to GMP CEO Mari McClure, the system has enabled the utility to retire four peaking plants that previously operated only during high-demand periods.

Participants gain resilience against outages. Bladyka's battery can sustain her home for two days during disruptions if non-essential loads are minimized. Megan Browning, another participant in northern Vermont, reported no power loss during a recent windstorm that affected neighboring homes. "Many houses in my neighbourhood lost power, but I didn't even notice a flicker," she said.

The model offers economic benefits. GMP reported saving customers $11 million collectively in the previous year through reduced infrastructure costs. The U.S. Department of Energy estimates virtual power plants could save the national grid over $10 billion annually by 2030 by deferring new power plant construction.

Challenges remain. Jen Downing, a former U.S. Department of Energy official, notes that utilities often lack financial incentives to adopt demand-responsive resources, as revenue models typically favor infrastructure investment over software-driven efficiency. Despite this, states including Massachusetts and Illinois are exploring regulatory frameworks to procure virtual power plant capacity.

GMP aims to expand its virtual power plant to serve all 300,000 customers who request storage solutions by 2030, potentially doubling its current capacity by 2034. The utility is also testing integration of thousands of electric vehicle batteries through vehicle-to-grid technology, though cost-effectiveness remains under evaluation.

The approach represents a shift toward decentralized energy management, where consumers simultaneously act as producers and consumers of electricity. As McClure stated, "We believe in a two-way grid... Customers really become consumers and producers."

This development occurs amid growing recognition of the need for resilient, low-carbon energy systems. With Vermont's cold climate and rural geography, prolonged outages can pose serious risks, making distributed storage increasingly valuable. The state's experiment offers a potential blueprint for other regions seeking to modernize grid infrastructure without massive capital investment in traditional power plants.