When we start a new solar ground-mount project with engineers, the foundation is always the first technical decision. Choose poorly, and you risk schedule overruns, structural issues, or unexpected costs. At Shandong Pinjie New Materials Co., Ltd., we have manufactured steel foundation products for over ten years. During that time, we have seen a clear shift from concrete to galvanized steel ground screws-not because of fashion, but because of what we have observed on real job sites.
What Are Galvanized Steel Ground Screws?
A galvanized steel ground screw is a steel pipe with helical plates welded to it. You install it by applying torque-using a hydraulic excavator or a portable driver-so it cuts into the ground and develops load capacity without excavation or concrete.
The steel is high-strength carbon steel, and corrosion protection comes from a hot-dipped galvanized steel coating. Our standard coating is applied per GB/T 13912, with thickness typically between 80 and 100 microns. We check coating quality on every batch using thickness gauges and adhesion tests. Before full production, we always run trial installations on site and perform load tests-because we have learned that soil conditions often differ from the geotechnical report.
What We Have Seen in the Field
In our experience, the biggest advantage of ground screws is installation speed. On a typical solar farm, one crew of five workers with a single pile driver can complete the foundations in a fraction of the time that concrete would require. For example, on a recent large project we supplied, the client finished all foundation work in about half the scheduled time compared to their previous concrete-based design. The crew installed hundreds of piles per day, and the system was ready for racking immediately-no waiting for concrete to cure.
We have also supplied piles for projects on difficult terrain: rocky hillsides, sandy deserts, and even seasonally frozen ground. In each case, we adjusted the helix design and pile length to match the local soil. The feedback from installation teams has been consistent: ground screws are easier to handle, produce less waste, and do not require heavy excavation equipment.
One site in a coastal area had concerns about corrosion. We provided piles with a thicker galvanized coating, and after eight years of service, inspection showed only minimal surface oxidation-well within expected limits. This matches what we see from independent corrosion studies: in normal outdoor environments, a hot-dipped galvanized coating can easily last 25 years or more. For reference, we regularly run salt spray tests on our products, and our standard coating typically shows no red rust after 1,000 hours of accelerated testing. That gives us confidence in recommending galvanized steel for outdoor use for solar projects.
Cost and Schedule Considerations
From a budget perspective, ground screws generally cost less than concrete footings when you factor in labour, equipment, and material transport. Concrete requires formwork, rebar, mixing, pumping, and curing-all of which add time and crew size. We have compared quotes from multiple projects, and the total foundation cost for screw piles is usually 20–30% lower than concrete, especially when the site is remote.
Schedule is equally important. A concrete foundation can take a week or more to reach sufficient strength. With ground screws, the structure is load-bearing the moment the pile is in place. This compression of the construction timeline often allows projects to qualify for earlier grid connection or to avoid weather windows that would delay concrete work.
Key Observations from a Decade of Manufacturing
Over the years, we have learned a few practical lessons:
Coating quality is critical. A uniform galvanized layer outperforms a thicker but uneven coating. We have rejected batches with minor defects because we have seen the consequences of field failures.
On-site testing saves time. We always recommend trial piles and load tests before mass production. In one case, the site turned out to have loose fill not shown in the report. We redesigned the pile length within two days, avoiding a major delay.
Experienced crews make a difference. We provide installation guidance with every shipment, and our records show that trained operators install piles faster and with fewer rejections.
Applications We Commonly Support
We supply galvanized ground screws for:
- Utility-scale solar farms, where speed directly affects project economics
- Commercial sites where concrete logistics are complicated
- Agricultural land, where minimal soil disturbance allows farming to continue
- Remote off-grid installations, where transporting concrete is impractical
In every case, the decision to use ground screws is based on site conditions and project goals, not on a one-size-fits-all rule.
Final Thoughts
If you are evaluating foundation options, galvanized steel ground screws are worth a serious look. The installation speed, cost savings, and long-term corrosion resistance are well documented in our project history. We do not claim they are right for every site-some soils or environmental conditions may favour other solutions. But for the majority of solar projects we have worked on, they have delivered reliable performance.
Shandong Pinjie New Materials Co., Ltd. has been manufacturing galvanized steel ground screws, helical piles, and related products since 2016. We work with solar developers, EPC contractors, and mounting system manufacturers worldwide. We base our recommendations on real field experience, not on theory. If you have questions about specifications or installation, we are happy to discuss your project.
