Solar energy is the radiant energy from the Sun 's light and heat, which can be harnessed using a range of technologies such as solar electricity, solar thermal energy (including solar water heating) and solar architecture. Below, you can find resources and information on the. The Sun produces electromagnetic radiation that can be harnessed as useful energy. Some PV cells can convert artificial light into electricity. Sunlight is composed of photons, or particles of solar energy. Professor of Engineering, Pennsylvania State University. Encyclopaedia Britannica's editors oversee subject areas in which they have. Solar energy is radiant energy from the sun—a fully renewable energy resource. We use the solar resource to provide daylight, electricity, and heat in four ways (in order of prevalence): Solar PV is the fastest-growing electricity resource in the world.