Geothermal at Scale
Darcy delivers its largest project to date: a 12-well, 2,150-ton groundwater geothermal system powering a 320,000-square-foot utility service center at The Heights development on St. Paul’s East Side — built to run without fossil fuels from day one.
Building Construction and Use
In November 2024, Xcel Energy broke ground on a new service center designed to anchor The Heights, a multi-use development on St. Paul’s East Side built on the site of the former Hillcrest Golf Course. The 320,000-square-foot facility is roughly twice the size of the company’s previous Rice Street location, which had served the region for more than a century.
The service center will house field crews, dispatchers, and design teams supporting Xcel Energy’s gas and electric distribution across the Twin Cities metro, along with fabrication shops, warehousing, fleet maintenance facilities, and office space. The site is designed to support 375 jobs at opening, with capacity to grow to 500.
Developed in collaboration with the Saint Paul Port Authority, The Heights aims to become one of the first net-zero communities in the country, targeting Platinum LEED for Communities certification. The service center’s design reflects that ambition at every level, from energy systems to employee wellness.
Why Geothermal?
From the earliest stages of design, the service center was planned to meet LEED Silver (v4.1) certification and Minnesota Energy Code (ASHRAE 90.1-2019) requirements. Xcel Energy’s broader commitments set the bar higher still: reducing carbon emissions 80% by 2030 and achieving 100% carbon-free electricity by 2050.
Darcy was selected to deliver a geothermal system that could meet those goals at the scale this facility demands. By using groundwater-enabled geothermal heating and cooling, the building operates entirely without fossil fuels for thermal comfort — across both office spaces and the service fleet environment. The Darcy system integrates naturally alongside the rooftop solar array and high-efficiency mechanical systems, creating a cohesive clean energy strategy rather than a patchwork of independent upgrades.
Design and Construction
At the time construction began, the Xcel Energy St. Paul Service Center was Darcy’s largest project ever completed, featuring a 12-well system spanning the full site. The scope required precise coordination across multiple construction teams and site conditions.
Two of the 12 wells were installed directly adjacent to three electric vehicle charging stations, a configuration that required close collaboration between the geothermal installation crew and the broader project team to sequence the work without compromising either system. During installation, Darcy’s geology and design teams also encountered an unexpected geologic anomaly beneath the site. Custom design solutions were developed and implemented without delaying construction milestones, reflecting the technical depth Darcy brings to complex, high-stakes projects.
Since commissioning, the system has performed as designed, operating efficiently and reliably to support round-the-clock utility operations across a facility that never stops running.
A Healthy and Sustainable Work Environment
The Xcel Energy St. Paul Service Center is as much an investment in people as it is in infrastructure. Beyond the geothermal system, the facility includes indoor air quality monitoring, bike storage, access to trails on bee-friendly lawns, bird-friendly glass, and 23 electric vehicle charging stations to support the company’s growing fleet. One megawatt of rooftop solar rounds out an energy strategy designed for the long term.
For the surrounding community, the facility is a resilience asset. When outages or disruptions occur, this is the hub that keeps crews mobilized and customers reconnected. By pairing that mission-critical reliability with a fossil-fuel-free energy system, Xcel Energy and Darcy have built something that delivers on operational, environmental, and community values at the same time.
