The photovoltaic (PV) industry is facing
challenges. Growth in the industry has slowed as
a result of lower government subsidies and
The good news for institutional and commercial facilities is that the development of more efficient, cost-effective solar panels, combined with volatile energy prices, still makes PV technology an attractive alternative for managing energy prices and supporting sustainability efforts. Maintenance and engineering managers considering installing a PV system need to consider several practical factors before, during, and after installation of a rooftop system.
A PV cell is a specialized semiconductor diode that converts light from the sun into direct current (DC). PV cells have no moving parts and require little maintenance. Rooftop application generally feature two primary types of panels:
Amorphous silicon panels. These panels consist of a thin layer of silicon deposited on a backing. This thin film can come in rigid panels or as a flexible lightweight panel that can be adhered to a membrane and fastened directly to the roof membrane.
Crystalline silicon panels. These panels are more common, generate more wattage, and are more durable than amorphous or thin-film panels. They typically are made by laminating the cells between tempered glass and plastic and framing it with aluminum. Thin panels require a larger surface area compared to a crystalline panel, due to their reduced efficiency. But in low-light conditions, thin-panel performance is better.
Also, PV systems are rated in watts, based on the amount of electricity they produce at maximum output. For example, a 1 kilowatt (kW) system will produce 1,000 watts of power at maximum output. A 15kW system will produce 15,000 watts of power at maximum output. Line loss, sunlight exposure, temperature, dust, and dirt on the panels can affect actual wattage PV systems produce.