Beyond Solar Modules: How BOS Costs Impact Solar Energy Affordability

The balance of system (BOS) costs associated with solar projects include all components of the system, excluding the solar modules themselves. These components include everything from wiring, inverters, mounting structures, and monitoring systems, to the labor and permitting required for installation. Reducing BOS costs is critical for making solar energy more cost-competitive with traditional sources of energy, and there are a number of strategies being employed to achieve this goal. One way to reduce BOS costs is to use low-cost materials for structural components. Simplifying designs and increasing automation can also help reduce costs. As the use of solar energy continues to grow, there is increased mass production, which can lead to economies of scale and further reductions in costs. Another approach is to use building-integrated PV (BIPV) products. BIPV products eliminate some elements of structural BOS entirely and offset building material costs. While BIPV products tend to be small modules with high operating temperatures, which can be barriers to cost competitiveness, they can still offer significant cost savings. Increasing the system voltage is another way to reduce electrical BOS cost and complexity. Higher system voltage allows for more modules per string and fewer strings, reducing the number of system components that scale with the number of strings, such as fuses, wiring home runs, and combiner boxes. Lastly, combining PV systems with battery storage can further reduce BOS costs. PV-plus-storage systems can be configured with AC-coupled or DC-coupled storage, realizing different levels of BOS cost savings over PV-only or storage-only system configurations. In conclusion, reducing BOS costs is a critical step for making solar energy more cost-competitive with traditional energy sources. Strategies such as using low-cost materials, simplifying designs, increasing automation, and combining PV systems with battery storage can all help reduce BOS costs and make solar energy more accessible and affordable for all.

Summary:

1. BOS costs include all components of a solar project except for solar modules themselves. Strategies to reduce BOS costs include using low-cost materials for structural components, simplifying designs, and increasing automation to benefit from economies of scale.
2. Building-integrated PV (BIPV) products can eliminate some elements of structural BOS and offset building material costs, leading to significant cost savings.
3. Increasing the system voltage can also reduce electrical BOS cost and complexity by allowing more modules per string and fewer strings, reducing the number of system components that scale with the number of strings.
4. Combining PV systems with battery storage can further reduce BOS costs and can be configured with AC-coupled or DC-coupled storage for different levels of cost savings.