refers to the emission of energy from the sun that travels in form of waves or particles like electromagnetic radiation. Radiation can be visible or invisible to the human eye.
Without the sun’s radiant energy, life on earth would not exist. Radiant energy travels to the earth at a speed of 186,000 miles/sec.
In applications involving transmission of power from one location to another, “radiant energy” is sometimes used to refer to the electromagnetic waves themselves, rather than their energy (a property of the waves). Because electromagnetic (EM) radiation can be considered to be a stream of photons, radiant energy can be viewed as the energy carried by these photons.