Radiant energy is the energy of electromagnetic waves, which includes visible light, radio waves, and infrared radiation. It travels through space and can be absorbed, reflected, or transmitted by different materials. This form of energy is essential for various processes, such as photosynthesis in plants and the warming of the Earth by the sun. Sources of radiant energy include natural phenomena like the sun and artificial sources like light bulbs. It plays a crucial role in technologies such as solar panels, which convert sunlight into usable electrical energy, highlighting its importance in renewable energy solutions.