Geothermal at Coveyou Scenic Farm

In today’s economy, small farmers have a difficult time competing with larger scale industrial farms to cut costs and maintain sustainable practices. That’s what David Coveyou experienced when he returned to revamp his family farm at the Coveyou Scenic Farm in Petoskey, MI.

Mr. Coveyou’s farm, a centennial farm founded in 1874 from the Homestead Act, has a resilient history. Through waves of small farm closings due to the rise of industrial agriculture, it has maintained its status as a family owned farm. Growing up on the farm, Coveyou’s parents encouraged him to pursue other careers since a future in farming had “no money and lots of work”. Yet, after working as an electrical engineer for 20 years, Coveyou decided to return to the farm to produce food organically and sustainably.

Coveyou wanted to instill sustainability as the guiding principle behind his enterprise, from growing organic produce to be sold locally to installing solar panels on his farm. However, producing vegetables requires energy intensive coolers that are expensive to run. In talking with other farmers, they complained about paying around $1,000 a month in electric bills for their walk-in coolers. He knew that as a small farming business, he needed to take advantage of opportunities to minimize expenses. “If we're going to build it, let's look at it from an engineering perspective,” said Coveyou. “Since we are starting out and we have to build this infrastructure, we have to build efficiently.” Coveyou wanted to find a solution that saved money and was sustainable. This led him to geothermal energy.

Coveyou wanted to try geothermal heat pumps as a solution, but local residential heat pump contractors were not sure if their systems could meet the energy demands of keeping the produce cool. The contractors were hesitant, but decided to take on Coveyou’s challenge.

The system they designed is a closed-loop geothermal system, where tubes of water or refrigerant are buried a few feet beneath the surface (known as a “geothermal field”) where the ground maintains a constant year round temperature of around 55 degrees Fahrenheit. During the summer, the system is used to cool the vegetables to 35-37 degrees Fahrenheit. The heat pump drives fluid through the tubes in the ground and heat transfers from the liquid into the much cooler ground. It needs less energy to reach 35 degrees in the walk-in chillers than if it was exchanging heat with the hot summer air at 80 degrees. During the winter, the system is used in the opposite manner where instead the ground heats up fluid in the geothermal field and the heat pump warms the floor of their greenhouse to keep seedlings at the appropriate temperature.

After lots of planning and a few days of installation, the project was a success in saving energy and cutting costs of operation. Although the heat pump uses electricity from the grid to run, the local utility offers a 3 cent/kWhr rebate, lowering the cost of electricity from 10 cents/kWhr to 7 cents/kWhr for the heat pump. The heat pump is also more efficient than a traditional refrigeration unit since it utilizes the temperature of the ground to help with some of the cooling. During the hot months of the summer, Coveyou only spends about $80/month on electricity for the cooling systems: a walk-in cooler, a field heat removal system, and a reach-in cooler for their market. In addition to saving costs, Coveyou boasts “the fact that we are able to generate BTu's [of cooling and heating] without burning any fossil fuels. That part is very appealing to me.”

The geothermal heat pump system helped Coveyou toward his financial and sustainability goals, and he’s excited to share his experience with others. In partnership with Geothermal ND, Coveyou plans to produce some flyers and information on the farm’s website that shares how the farm used geothermal energy with his customers, and how others can use it for their own applications to reduce costs and energy consumption. Coveyou’s farm has also been nominated for the Michigan Energy Excellence award twice, recognizing his efforts for employing innovative clean energy technologies.