Racking
Solar racking (also called mounting hardware or mounting structure) is the structural system that physically supports and positions solar panels at the correct tilt angle and orientation for maximum energy production. Racking must support panel weight, wind loads, and snow loads while meeting building code and local permit requirements.
Racking represents approximately 5–10% of total residential installed cost and 8–15% of utility-scale installed cost.
Types of Solar Racking
Roof-mount (residential):
- Flush mount: Panels mounted parallel to roof surface (most common for pitched roofs). Low profile, minimal wind loading.
- Tilt mount: Panels tilted at an angle above a flat or low-pitch roof for better solar angle.
- Ballasted: No roof penetrations — weighted blocks hold the racking in place on flat commercial roofs.
Ground-mount:
- Fixed-tilt ground mount: Panels on driven piles or ground screws at fixed tilt angle. Simple, low-maintenance, cost-effective.
- Single-axis tracker: Panels rotate on a north-south axis (see: Single-Axis Tracker).
- Dual-axis tracker: Panels track both azimuth and elevation for maximum irradiance capture. High cost, used for concentrating PV.
Carport / Canopy: Elevated structures over parking areas. More complex engineering, higher cost.
Key Racking Specifications
- Wind load rating: Racking must withstand local design wind speeds per ASCE 7 standards
- Snow load rating: Must support local ground snow load (GSL)
- Material: Aluminum (residential), steel (utility-scale)
- Certification: Racking systems require UL or ICC certification and engineered stamped drawings for permit
Leading racking manufacturers include IronRidge, Unirac, GameChange Solar, and Array Technologies.