Solar energy is one example of an inexhaustible resource. The energy from the sun is infinitely available despite incessant human consumption. The sun is the primary energy source of all living creatures.
An inexhaustible resource is any source of energy that is continuously available and can be replenished. This includes biomass, geothermal and wind energy. A resource is considered as renewable or inexhaustible only if the recovery and replenishment of the resource exceeds the consumption rate. Water, for example, is a renewable energy because the surface and underground water supply is replenished through rain and snow. In areas where there is very little precipitation, the rate of recovery is slow and water is almost nonrenewable.