Because almost ALL sources of energy on Earth derived originally from sunlight.
(Exceptions are gravity sources [earthquakes] and thermal vents.]
The primary is the sun
the sun
the sun
The Sun is Earth's primary external energy source. Solar radiation emitted by the Sun provides heat and light energy to sustain life on Earth through a process called photosynthesis.
The sun is not considered a primary consumer. In an ecosystem, primary consumers are organisms that directly consume producers (plants or autotrophs) for energy. The sun is the primary source of energy for almost all life on Earth, making it the ultimate source of energy in the food chain.
The primary source of Earth's energy is the sun. This energy is called solar energy, which is harnessed through various processes like photosynthesis, wind energy, and solar panels.
sun
the primary source of energy is sun.
Sunlight is Earth's primary source of energy.
Radiation from the Sun.
The Sun.
Sun