Solar PV systems can reduce energy costs and carbon footprint. They're also complex, 25-year investments. Here's a primer on how solar works, and how to make it work for you.
Turning Sunlight into Energy
Solar photovoltaic (PV) cells convert the energy in sunlight (photons) into direct current (DC) electricity using semiconductors. A typical commercial solar PV module is comprised of 60 to 96 photovoltaic cells connected in a series, placed between glass and a composite laminate, and surrounded by an aluminum frame. PV modules are mounted to a metal framework known as racking to form an array.
The DC electricity produced by a solar PV system is converted to alternating current (AC) electricity for use by onsite loads and/or for export to the electricity grid. The conversion from DC to AC electricity is performed by an inverter. Inverters range from small “micro” inverters located on each panel to large centralized inverters converting electricity from thousands of modules.
A Fine Balance
Modules, racking and inverters are considered major components in a PV system. The rest are collectively referred to as the “balance of system” (BOS) equipment. The majority of the BOS equipment is standard electrical equipment optimized for solar applications. Monitoring equipment is specialized for PV and designed to provide real-time metrics on system performance and environmental conditions. Data is transmitted via cellular telephone network or onsite internet connections and is accessible through web-based applications.