NGWA broke ground on its geothermal retrofit at headquarters on August 22 in Westerville, Ohio.
Utilizing the geothermal tax credits available for nonprofit organizations that were signed into law in 2022, NGWA selected Jackson Geothermal of Mansfield, Ohio, to drill 20 boreholes for a vertical closed loop system. The company drilled two test boreholes with its Versa-Drill V-100NG drilling rig in the lower level of the building’s parking lot that were both set with 65 feet of temporary casing.
The drilling formations encountered were: 0 inch-2 inches asphalt, 2 inches-1 feet gravel fill, 1 foot-18 feet sandy gray clay, 18 feet-36 feet coarse gravel, 36 feet-45 feet sand, 45 feet-58 feet clay and gravel, 58 feet-65 feet hard gray shale, 64 feet-108 feet light gray shale, and 108 feet-305 feet gray shale.
All bedrock was dry. Jackson Geothermal drilled the top 65 feet with fluid drilling, then set casing, and drilled out of the casing with air. It used a polycrystalline diamond compact (PDC) bit to drill the rock formation.
After drilling the borehole, the loop was set, the borehole was then grouted from the bottom all the way up to the bottom of the casing at 65 feet. The casing was then removed, and the remainder of the hole was grouted up to the surface.
The 18 remaining boreholes are scheduled to be drilled over the next month. The vertical closed loop system will replace the Association’s outdated HVAC system that it has used since moving to its current location in September 1996.
This isn’t the first time NGWA has supported geothermal. The Association had an open loop heat pump using a water well installed in a new building that became its headquarters in 1985 in Dublin, Ohio. Its Airport Drive building in 1995 in Columbus was fully geothermal where more than 100 boreholes were drilled by the company of long-time geothermal advocate, the late Ralph Cadwallader of Texas. There was a geothermal unit set up for training among many others (dozens).
Like at its previous headquarters, NGWA will use its vertical closed loop system to educate the industry and public about geothermal. NGWA is also making the most of its geothermal retrofit by hosting a short course, Geothermal Drilling and Grouting Fundamentals, on August 29. Attendees will learn about the equipment and tools used to drill and install vertical ground loops. They will also learn the proper procedures for grouting geothermal boreholes. Click here to learn more and register.
NGWA’s geothermal retrofit is made possible by these industry partners:
- AMTROL Inc.
- Bergerson-Caswell Inc.
- ClimateMaster Inc.
- Enertech Global LLC (GeoComfort)
- Federal Elite Heating & Cooling Inc.
- Grundfos
- Jackson Geothermal
- Preferred Pump & Equipment
- Salas O’Brien
- WaterFurnace International Inc.
- Xylem.