Flat-plate collectors are devices used to capture solar energy for heating purposes. They consist of a flat, insulated box with a transparent cover that allows sunlight to enter while minimizing heat loss. Inside, a dark absorber plate absorbs the sunlight and converts it into heat, which is then transferred to a fluid, usually water or air, circulating through the collector. These collectors are commonly used in solar water heating systems and can be installed on rooftops or in open areas. They are an efficient and cost-effective way to harness solar energy, contributing to renewable energy solutions and reducing reliance on fossil fuels.