What is the primary source of energy for Earth?

The primary source of energy for Earth is the Sun. Solar energy drives most of the processes on our planet, including photosynthesis in plants, which forms the basis of the food chain and energy flow within ecosystems. Additionally, solar energy influences weather patterns and ocean currents, playing a crucial role in climate regulation.

While volcanic activity and fossil fuels do contribute to energy sources on Earth, they are secondary forms of energy. Volcanic activity releases energy stored within the Earth but is not the main driver of energy for sustaining life or weather systems. Fossil fuels, derived from ancient organic matter, provide energy but ultimately originate from the solar energy captured by plants millions of years ago. The Moon, while it has some influence on Earth—such as tides—does not provide energy for processes such as photosynthesis or climate. Thus, the Sun stands out as the fundamental source of energy essential for life and ecological balance on Earth.