Why We’re Using It
A geothermal heat pump (GHP), or geo-exchange, is a clean, efficient renewable energy technology that uses heat generated and stored in the earth to heat and cool a building. Although the outside air temperature can differ dramatically between geographic regions and seasons, the ground below the earth’s surface remains a fairly consistent 50-65 degrees.
River Vine Vineyards will utilize geothermal energy as part of an Integrated Energy System (IES) that services the home’s heating and cooling needs. The ground absorbs 47% of the sun’s heat as it hits the earth’s surface—heat energy that River Vine’s geothermal system can collect and convert to electricity. A GHP will help maximize efficiency by channeling ground-source energy to fuel the home’s radiant heating and cooling system, maintaining a comfortable interior temperature year-round.
How It Works
River Vine’s geothermal system will consist of two main components: a geothermal unit and a series of underground pipes that will transfer heat between the earth and the house. A horizontal trenched ground loop will be installed five feet below the working vineyard on 20-feet centers, centerline of every other pair of vines. Since Lodi is a moderate climate, the property’s average annual ground temperature is 65 degrees— warmer than the air above it during winter and cooler than the air above it in summer. Using a heat exchanger, the GHP will efficiently loop heat from the ground to the house in winter and from the house to the ground in summer.
River Vine’s geothermal system will work in tandem with an air handler unit to keep interior air healthy, comfortable and clean. On extremely hot or cold days, the air handler and geothermal system will integrate seamlessly to maintain a comfortable 68-70-degree target temperature range. All air will run through a whole house air cleaner, ensuring superior Indoor Air Quality (IAQ) in every room at all times.
In the winter, River Vine’s geothermal system will use the ground loop to pull heat from the earth. Heat will be absorbed by a water solution as it circulates through the pipes, carrying warmed water into the home. A water-to-water GHP will concentrate the thermal energy and transfer it to heat energy for the radiant floor system, which will bring rising heat to the floor’s surface and upward into each room.
In the summer, the process will be reversed to create cool, conditioned air inside River Vine. The GHP will transfer heat from the inside air to fluid in the ground loop and move it back to the earth. The vineyard’s irrigation system will naturally cool the soil during the hot summer months.