SunTrain Announces Grant Collaboration for Colo. WATT Pilot Project

Most of Colorado’s low-cost renewable energy is from wind, which is generated far from where it is needed, the company noted. This innovative solution, says SunTrain, which is collaborating with Xcel Energy-Colorado, the National Electrical Contractors Association (NECA), and the International Brotherhood of Electrical Workers (IBEW), “would add to the clean energy already delivered by conventional power lines to provide more low-cost clean energy to Colorado consumers.”

According to a report by The Colorado Sun, if the project’s supporters land a $10 million federal grant, “a demo project charging trains at Pueblo and plugging into the grid at Denver’s Cherokee power station could be ready by 2026.”

SunTrain says each one of its railcar-sized iron phosphate battery banks “holds enough power for 20,000 homes for an hour, or 1,000 homes for a full day,” according to The Colorado Sun report. “The first-of-its-kind demonstration in Pueblo would start with 20 battery-packed railcars, with the electrical and rail technology eventually supporting 100-car battery trains providing temporary power for hundreds of thousands of people.”

The initial trains would be diesel powered, but even those would “still make the battery power some of the cleanest energy around,” SunTrain officials said in a rollout at Xcel’s Cherokee plant in north Denver, according to The Colorado Sun report.

SunTrain will be supported by Colorado Governor Jared Polis, who the company says “will share his strong support for the WATT federal grant application and for the broad-based collaboration of business, labor, environmental and legislative leaders working to foster the development of WATT and other rapidly deployable advanced technologies.”

“Working with our outstanding collaboration partners, SunTrain hopes to expand upon Colorado’s outsized role in addressing climate change by completing our technology development and deploying our first grid-scale pilot project here,” said SunTrain CEO Jeff Anderson. “As a result of our collective efforts, the WATT project will pave the way for SunTrain’s commercialization and mass adoption in Colorado and nationally.”

According to SunTrain, Polis, who has championed policies for Colorado to achieve 100% clean energy by 2040, “was encouraged enough by the proposed pilot to write a letter to federal agencies strongly supporting the SunTrain grant application.” In the letter dated Oct. 20, 2024, Polis wrote:

“In storing gigawatt-hours of clean energy from solar and wind in battery railcars that are then transported over existing freight rail networks, SunTrain offers a creative alternative to traditional transmission. This provides an immediate, alternative connection between renewable energy generation and load, bypassing the congested transmission system. Importantly, it also supports an economic transition for workers and communities by replacing lost coal transport business with battery freight cars and repurposing retiring fossil fuel power plants as charge/discharge points.”

“The WATT project is but one demonstration of Xcel Energy’s continuing commitment to provide affordable, carbon-free energy by adopting innovative solutions that solve the [problems] related to the clean energy transition,” said Xcel Energy-Colorado President Robert Kenney. “We are joining SunTrain and NREL (National Renewable Energy Laboratory) in requesting federal ARPA-E funding for the WATT project to potentially host this first-in-the-nation pilot project right here in Colorado. We will continue to work with our collaboration partners, the Governor, legislative leaders and the Colorado Public Utilities Commission (PUC) to determine how best to make all innovative technologies, like SunTrain, a reality in Colorado.”

“NECA fully supports the efforts of SunTrain, Xcel Energy and NREL in their pursuit of this grant and will stand in coalition with these parties to ensure that there is a clear and attainable regulatory trajectory to allow pilot programs like this to proceed,” said Jeff Vera, Colorado NECA Board Member.

“Developing advanced technologies is critical to ensure baseload capacity for Colorado’s power grid of the future and provide real opportunities for a Just Transition at our retiring coal facilities,” said IBEW Local 111 Business Manager Nate Gutierrez. “We proudly stand with SunTrain and Xcel Energy to commit our membership’s political power and support to pursue the legislative and regulatory steps necessary to make Colorado the first state in the nation to deploy SunTrain.”

“Railroads are willing to work with newer lithium-iron phosphate batteries because they are not flammable, and much less volatile than older lithium-ion batteries,” executives said, according to The Colorado Sun report, which added that “the newer batteries also use fewer rare-earth metals whose mining is causing environmental problems around the world. Hauling batteries can help replace business lost to the closure of coal-fired or oil-fired power plants around the nation.”

In a post on X, Union Pacific (UP) wrote that it “continues to transport energy by rail” and that the Class I’s existing infrastructure “can provide a resilient renewable energy delivery system.”

According to The Colorado Sun report, SunTrain and other backers mentioned multiple scenarios where the battery trains could be attractive:

• “Bridging deliveries of solar or wind energy not yet connected to a power grid, and at times of the day when urban areas see demand surges. Train-based batteries can store wind power generated at nighttime off-peak hours, and deliver it to substations or be parked as backup.
• “Powering remote needs that are not on the grid but are near current or abandoned rail lines. Music festivals similar to Coachella have already expressed interest.
• “Providing new or backup power to artificial intelligence data centers without further stressing existing power plants or transmission lines. Some AI executives have even started pursuing their own nuclear power plants as a reliable source of energy as data centers explode.”

SunTrain, which has been financed by venture capital so far, said that if the federal grant does not come through, it could seek additional private capital or an alternative combination of research and development grants, according to the Colorado Sun report.

“If the project proves out, SunTrain could have 100-car trains waiting at either end and run charged and discharged trains in either direction, every day,” said SunTrain Co-Founder and Chief Technology Officer Chris Smith, according to the report. If the project fails, “it’s all on wheels,” Smith said, meaning the powerful batteries “can be rolled elsewhere for other projects or uses.”

During the 2025 Colorado General Assembly, SunTrain said it will continue to work with Xcel Energy and the other key stakeholders to engage with Governor Polis, the Colorado Energy Office and Colorado legislative leaders “to ensure that innovative rapidly deployable technologies like SunTrain have a clear statutory and regulatory glide path to become a reality in Colorado.”