Solar Panel / Solar Module

A solar panel (also called a solar module) is a device made up of multiple photovoltaic cells that captures sunlight and converts it into electricity. The terms “solar panel” and “solar module” are interchangeable in residential solar contexts.

A standard residential solar panel contains 60 or 72 silicon-based PV cells laminated between protective glass and a backsheet, framed in aluminum for durability. Modern panels typically produce 350–450 watts each and measure roughly 65 × 39 inches. Most manufacturers guarantee at least 80–85% of original output after 25 years, though real-world degradation rates average just 0.3–0.5% per year. Panels are rated under Standard Test Conditions (STC) at 25°C and 1,000 W/m² of sunlight, so actual output varies with temperature, shading, and orientation.