Solar photovoltaic (PV) installations can deliver clean energy but discouraged uptake due to the high front-end costs related to the balance-of-system (BOS) materials, such as those associated with mounting and framing. Solar Metal components, which are engineered to last longer and operate more effectively, can reduce costs associated with these materials by 20-30%, allowing for deeper adoption of PV energy systems at scale.
The term BOS refers to the components that are not the solar PV modules, such as racking or mounting hardware, trackers, and inverters. Racking systems are made from aluminum extrusion products, which provides a much higher strength-to-weight ratio (yield strength ~300 MPa) than galvanized steel, allowing for ground-mount systems that can withstand winds up to 150 mph at about half the cost of steel systems. Galvanized steel racking systems, with an outer coating of zinc to preclude corrosion, can also be used with rooftop PV systems, providing a lifetime of over 25-years with little-to-no maintenance.
Innovation in design has allowed for reduced material consumption. Topology-optimized brackets reduce the number of weld points, eliminating up to 40% of the fabrication time through rolling-forming, which is automated, and increases reliability with fewer attachment points. With single axis trackers, torque-tube assemblies made from high-tensile steel have demonstrated a 25% increase in energy yield due to optimized tilt angles, allowing for amortization of BOS expenses over higher output.
Economies of scale extend cost savings. Pre-galvanized parts come ready for site installation eliminating labor for installation which falls from 0.5 hours per panel to 0.3 hours per panel in comparison. In utility-scale farms, similar to some in the Mojave Desert, the application of modular metal frames can be accomplished very quickly - up to 1 MW in a few weeks. In addition, these alloys can be recycled to either hold labor or contribute to a circular economy.
Supply chain volatility can be reduced with localized forging following the production of components to location - reducing transport emissions, cost of shipping and tariffs. As bifacial panels come, reflective metal surfaces add to albedo and drive levelized cost of energy (LCOE) down below 0.03/kWh.
Improving durability of BOS structure, without negatively impacting cost allows for a more complete PV rollout, and just a more sustainable grid, but a better overall value.
