An example of a source of energy which is both inexhaustible and renewable is our Sun. It generates energy as a result of nuclear fusion and we receive this in the form of light energy. Green plants use it in photosynthesis and generate oxygen and food from it. This food, in the form of glucose molecules, is used up by the plants to form more complex molecules, which are ultimately consumed by us. We generate energy out of this food by cellular photosynthesis. We can also use the sun's energy to produce electricity (by photovoltaic cells, also known as solar cell), cook food (in solar cookers) and generate heat (in photothermal cells). Solar cells are the most common application of solar energy and can be used at homes, as isolated devices, or can be used to make solar farms to generate large amount of electricity.
The sun has a certain life span, running into billions of years and hence from our perspective can be thought of as inexhaustible.
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