Uranium is an example of a non-renewable energy resource. Uranium has the highest atomic weight of all naturally occurring elements with an atomic number 92. Uranium was discovered in 1789 by Martin Klaproth who named his discovery “uran” after the planet Uranus. It is highly radioactive, and, its radioactive properties were not recognized until 1866. Uranium’s potential for use as an energy source was not manifested until the mid-20th century.