en.Wedoany.com Reported - The Old Hill Farm solar project, located in Jefferson Valley, New York, and developed by Woodfield Renewable Partners, successfully deployed a 6,106,490-watt system capacity on sloped and uneven terrain using DCE Solar's Long Span ground screw mounting system. The project features 11,414 Canadian Solar modules, with installation carried out by DCE Services, including mechanical installation and pre-drilling, ensuring seamless execution.
The site's irregular steep slopes ruled out traditional driven-pile fixed-tilt solutions. Leveling the site to the tolerances required for standard pile systems would have significantly increased civil costs and introduced additional environmental review risks. Therefore, Woodfield chose a mounting system that naturally adapts to the terrain—DCE Solar's Long Span fixed-tilt ground mount with ground screw foundations. This system uses a structurally independent unit design, allowing loads to be distributed independently across the array without relying on a continuous reference grade, thus avoiding extensive earthwork leveling.
Before mechanical installation began, the entire site was pre-drilled to characterize subsurface resistance beneath the slope footprint, providing the installation team with real soil data to ensure consistent embedment depths across irregular terrain. DCE Services installed 2,620 ground screws, each 2,100 mm long, manufactured from G115 steel, achieving the embedment depth targets specified in the geotechnical report under varying soil conditions. The structure was analyzed per ASCE 7-16, with a design wind speed of 105 mph and a ground snow load of 30 psf, meeting the load requirements for ground-mounted solar projects in the northeastern United States.
The 11,414 Canadian Solar modules were installed at a fixed 15° tilt angle, maintaining a minimum ground clearance of 30 inches across the entire array. The tilt angle, ground clearance, and long-span foundation geometry were coordinated within the engineering package to maintain consistent row spacing and meet load performance requirements under the analyzed wind and snow conditions.
The project was completed at 6,106,490 WDC, which would have required substantial civil modifications if a traditional pile foundation system had been used. Limiting earthwork reduced costs and kept the schedule on track.
Tyler Bonini, Principal at Woodfield Renewable Partners, stated: "Its robust design, combined with the ability to cover large areas with minimal structural components, made it the perfect solution. The system is versatile, durable, and cost-effective." Lessons learned from the Old Hill Farm project indicate that on sites with significant grade changes, foundation selection is both a structural and civil cost decision; ground screw systems with greater spanning capacity reduce the total number of foundations and required civil intervention, while the pre-drilling strategy was effective because subsurface conditions were documented in advance.
