(N/A) Two renewable sources of energy are as follows:
$(a)$ Sun: The energy derived from the Sun is known as solar energy. Solar energy is produced by the fusion of hydrogen into helium and other heavy elements. $A$ large amount of hydrogen is present in the Sun,allowing it to replenish on its own. The Sun is expected to continue burning for another $5$ billion years. Hence,solar energy is a renewable source of energy.
$(b)$ Wind: Wind energy is derived from air blowing at high speeds. Wind energy is harnessed by windmills to generate electricity. Wind is caused by the uneven heating of the Earth's surface by the Sun. Since this heating process will continue as long as the Sun exists,wind energy will remain available indefinitely.