A fuel that is used as an alternative to a fossil fuel is known as alternative energy. The term normally implies that the alternative energy fuels are basically not traditional fuels and also have lesser impact on the environment. The term may be used in order to differentiate from the fossil fuels, while they are also used in an interchangeable way with the term renewable energy. There are various definitions of the term alternative energy.
As per the Oxford Dictionary alternative energy may be defined as the energy that is fuelled in a way that is not harmful for the environment and does not eat up enormous amounts of natural resources. According to the Princeton WordNet alternative energy is a form that is extracted from sources which do not affect the environment in a negative way or consume substantial amount of natural resources.
According to Responding to Climate Change 2007 alternative energy is a form of energy that is drawn from the untraditional sources of energy like winds, compressed natural gases, hydroelectricity and solar sources. The Natural Resources Defense Council opines that alternative energy is one, which is peripheral and is more environment-friendly compared to other types of fuels like fossil fuels. In the respect of environment-friendliness the alternative energy forms are similar to wind energy and solar energy.
The Materials Management Services opines that the alternative energy is another name for sources of fuel that have not been extracted from fossil fuels. As per the definition provided by them alternative energy can also be used as an alternative for the renewable energy forms. Some of the common examples of alternative energy are wind energy, wave energy, solar energy, tidal energy and biomass. Nowadays there are various sites that are providing the latest information on the various forms of alternative energy.