Surface power density is an important factor in comparison of industrial energy sources.
Measured in W/m2 it describes the amount of power obtained per unit of Earth surface area used by a specific energy system, including all supporting infrastructure, manufacturing, mining of fuel (if applicable) and decommissioning.
[4] The following table shows median surface power density of renewable and non-renewable energy sources.
[5] [W/m2] As an electromagnetic wave travels through space, energy is transferred from the source to other objects (receivers).
The following equation can be used to obtain these units directly:[6] The simplified relationships stated above apply at distances of about two or more wavelengths from the radiating source.