Geothermal technology is a key component of River Vine’s Integrated Renewable Energy Systems, harnessing solar energy stored in the earth to power the home’s hydronic radiant heating and cooling system for year-round climate control.
Unlike the ambient air temperature, the upper ten feet of the earth’s surface maintains a consistent temperature between 50°F and 65°F throughout the year. Located in Lodi’s Mokelumne Agricultural Viticultural Area, River Vine enjoys a moderate climate with an average annual ground temperature of 65°F — warmer than the air above it during winter and cooler than the air above it in summer. River Vine’s geothermal system uses underground pipes to tap into the stored ground energy and pump it into the indoor air delivery system, effectively moving heat from the ground into the home during cold months and removing heat from the indoor air and transferring it to the ground in warm months.
To maximize energy efficiency, we installed the geothermal pipes in the vineyard, where the cooling effect of the vineyard’s irrigation system will lower the ground temperature and make River Vine easier to cool during Lodi’s hot summer. We took advantage of a dry weather day to excavate trenches between the vines in preparation for laying pipe. Geothermal systems start with an earth loop that is either open or closed, with underground pipes positioned horizontally or vertically, using either straight runs of pipe or overlapping coils. River Vine’s geothermal system is a closed system, utilizing horizontal straight loops that run in between the vines. Closed loops are environmentally friendly, continually circulating the same water solution throughout the loop field, sealing the liquid inside to prevent it from seeping into the ground.
We factored in building dimensions, soil type and climate to calculate the quantity of loop needed. River Vine’s sandy soil absorbs less heat, so a larger loop field was required to consistently meet the home’s heating and cooling demands during all seasons. We ran ten horizontal loops of polyethylene pipe, at over 800 feet per loop, for a total run of more than 8,000 feet. An alternative to metal and PVC pipe, polyethylene is corrosion-free, engineered to perform consistently and efficiently over time, without wearing out or weakening. Investing in higher grade pipe with greater rigidity, thermal conditions and chemical resistance helps ensure that the system will last the lifespan of the house, efficiently heating and cooling River Vine for generations.
When installation is finished, River Vine’s integrated geothermal and radiant heating and cooling systems will provide a reliable source of free energy, delivered quietly and efficiently to all areas of the home, with no environmental impact and minimal maintenance required.
You can find more photos in our River Vine Progress Gallery and on our Geothermal and Radiant Heating and Cooling system pages.