Thermal Energy, or heat, is the internal energy in substances; it is the vibration and movement of the atoms and molecules within substances. The more thermal energy in a substance, the faster the atoms and molecules vibrate and move. Geothermal energy is an example of thermal energy. By creating the new devices and methods to concentrate, store, and transport naturally-created thermal energy, human beings can reduce dependence on non-sustainable forms of energy.
Thermal energy is generated to measure by heat of any kind. It is caused by increased activity or velocity of molecules in a substance, which in turn causes temperature to rise accordingly. There are many natural sources of a thermal energy on Earth, making it an important component of alternative energy.
Thermal energy is quantified by temperature (e.g., the physical property of a system which underlies the common notions of "hot" and "cold"; material with the higher temperatures are said to be "hot"). Heat (also heat change) is the transfer of thermal energy between two bodies which are at different temperatures. The SI unit for heat is the joule.
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