Going Geothermal: Pitkin County couple heats house using nearby natural hot spring

William and Annette Vannice power their home near Redstone using geothermal energy harnessed from a natural hot spring located on their property. 

The spring, situated near the Crystal River’s Penny Hot Springs along Colorado Highway 133, produces water at 125 degrees Fahrenheit — too hot for soaking, but ideal for heating a home and eliminating snow buildup on the driveway.

William Vannice said he purchased the land specifically for its geothermal potential. 

“I decided to research and find answers on how the hot water could heat the house,” he explained. “My engineering brain, which an engineer would not agree with, started to dig into some solutions, and Aspen’s (Community Office for Resource Efficiency) helped connect with an individual who could set up the process.”

Through research and support from CORE, William Vannice discovered he could heat the entire house and maintain a snow-free driveway throughout the winter. 

“My utility bill is close to zero, minus the energy needed to power the pumps for the water,” he said. “There are zero fossil fuels needed for this process, which makes the project worth taking on. My wife thought I was crazy at first, but then she joined, and joked that we were both crazy.”

The couple demolished the original structure on the property and built a new home designed from the ground up to integrate geothermal heating.

“I incorporated the hot water technology to heat everything in my house — to the heat itself, to hot water to the showers, flooring, and sinks,” William Vannice said. “The ideal temperature to run a radiant system is between 100 to 110 degrees. Since the heat of the springs is 125, I somehow managed to do it — I am not sure how I did it — but it is a closed loop system that runs into the springs.”

The system, he explained, operates like a traditional boiler, but uses the natural hot spring as its heat source. The setup includes 385 feet of piping with 65 feet of lift. 

“When the water gets to the house, it acts as a normal system, where a thermostat opens up valves, keeping the house at a constant 72 degrees through radiant flooring,” he said. “The leftover water after the house goes to the sidewalks, driveway, and decks.”

According to Vannice, the system is powerful enough to heat up to 250 homes, though in his case, it is entirely dedicated to his residence and property.

Tim Johns, a senior energy concierge with CORE, confirmed that the Vannices’ system operates as a closed-loop circuit, where hot water circulates continuously between the house and the spring. 

“Water is constantly circulating from his house to the spring. Will and Annette can control the amount of water that is coming to the house to control the temperature. He can essentially cut off the supply and open it back up when he needs more heat,” Johns said. “I have never seen another home like this. He used creativity to essentially heat his home.”

Johns emphasized that while geothermal systems like this one have enormous potential, they aren’t universally applicable. 

“It requires a lot of creativity, and Will really took this by the reins. All he has to pay for is the water pumps,” he said. “He uses this to heat his domestic hot water and space heat for free.”

Not every property, however, can support a similar setup. 

“It’s really convenient for Will, because he can pull hot water from the river. For others, they may need to drill bore holes, which will be significantly more costly than what Will has done,” Johns said. “There is certainly a ton of potential in this valley for the technology, but it could just cost a lot of money.”

He added that each geothermal project depends on the specific characteristics of the land and resources available. 

“The key is to use what is available for that person and their property,” Johns said. “Will’s approach won’t work everywhere, but it’s an impressive example of what’s possible.”

For William Vannice, the process started with a leap of faith. 

“The first step is the hardest, which is deciding to do this, because that scares everyone,” he said. “Until I turned the switch on and felt hot water on my floor, I wasn’t sure it was going to work. Everyone in the industry told me I was crazy and it wasn’t going to work. They said my water was too hot, but I made it work.”