In one line
All components of a solar installation other than the modules — inverters, mounting, cabling, transformers, monitoring.
What it means
Balance of System (BoS) refers to everything in a solar plant outside the modules themselves: inverters, mounting structures and trackers, DC and AC cabling, combiner boxes, transformers, switchgear, monitoring systems, and the foundations and civil works. BoS typically accounts for 35–50% of utility-scale solar capex.
Related terms
Browse every term in the renewable energy glossary, or read the latest analysis on Solar PV.