Classification and Selection of Solar Mounting Systems

I. Concrete Pile Foundation

    A pit is dug and concrete is poured to form a pile, with anchor bolts embedded to connect the support columns. The advantages are high load-bearing capacity and suitability for various soil types. The disadvantages are that construction is slow (requiring 24–48 hours of curing) and it occupies a large area. Suitable for large-scale ground-mounted power stations and areas with high wind speeds.

2. Screw Pile Foundations

    Steel pipes fitted with spiral blades are driven into the ground by machinery, much like screwing in a screw, without the need for excavation or concrete pouring. The advantages are that installation is extremely fast, there is no excavated waste, and the system is ready for use immediately upon completion. The disadvantage is that they cannot penetrate large boulders. Suitable for small to medium-sized projects on clay or sandy soil.

3. Precast Concrete Foundations

    Concrete blocks prefabricated in a factory are transported to the site and placed directly. The advantages are extremely rapid construction and the ability to relocate and reuse them. The disadvantages are high transport costs and the need for a level, firm foundation. Suitable for flat-roof ballast systems or hard sites where transport is convenient.

4. Bored Pile Foundations

    A hole is drilled first, a steel cage is inserted, and then concrete is poured. Advantages include extremely high load-bearing capacity and a small footprint; suitable for soft soil or backfilled areas. Disadvantages include the need for large drilling rigs and a relatively long construction period. Suitable for large power stations or sites with very poor ground conditions.

5. Ground Screw Foundations

    Small-diameter screw piles that can be driven into the ground by two people using a lever wrench. Advantages include being lightweight and requiring no heavy machinery. Disadvantages include low load-bearing capacity. Suitable for small garden systems with 1–6 panels.

Summary of Selection

    If the soil is of good quality and you wish to save money and effort, choose screw piles; if there are strong winds or poor soil conditions, choose concrete isolated foundations or cast-in-situ piles; for flat roofs, choose precast ballast blocks; if installing just a few panels for personal use, ground screws will suffice. Remember: carry out a site survey first, make decisions based on data, and do not rely on gut feeling.