The balance of system (BOS) encompasses all components of a photovoltaic system other than the photovoltaic panels. This includes wiring, switches, a mounting system, one or many solar inverters, a battery bank and battery charger.
Other optional components include renewable energy credit revenue-grade meter, maximum power point tracker (MPPT), GPS solar tracker, Energy management software, solar concentrators, solar irradiance sensors, anemometer, or task-specific accessories designed to meet specialized requirements for a system owner. In addition, concentrated photovoltaics systems require optical lenses or mirrors and sometimes a cooling system.
In addition, ground-mounted, large photovoltaic power station require equipment and facilities, such as grid connections, office facilities, and concrete. Land is sometimes included as part of the BOS as well.