Solar modules, also known as photovoltaic modules, are the building blocks of solar panel systems. They absorb sunlight and convert it into electrical energy through the photovoltaic effect. These modules are typically installed on rooftops or in open areas. This guide explains how solar panels work, compares technologies, breaks down costs and incentives, and walks you through sizing, installation, maintenance, and environmental impact—using data from NREL, IEA, IRENA, LBNL, and other credible sources. What are solar panels? Types and key components. Technology Convergence is Accelerating: The solar industry in 2025 is experiencing unprecedented technological convergence with heterojunction (HJT), bifacial modules, and emerging tandem perovskite-silicon cells pushing commercial efficiencies toward 25% while laboratory demonstrations exceed 34%. They're getting more popular as they get better and cheaper. This guide helps you grasp solar modules. You'll learn what they are, how they.