Solar power is one kind of clean energies that are forms of energy which do

Solar power is one land of clean energies that are forms of energy which do not pollute the air, the ground, or the sea. It (36) describes a number of methods of producing energy from the light of the Sun. For example, solar power is produced by collecting sunlight and (37) converting it into electricity. It has been present in many (38) traditional building methods for centuries , but has become of (39) increasing interest in developed countries as the environmental costs and limited (40) supply of other power sources such as fossil fuels are realized. It is already in widespread use where other supplies of power are absent such as in remote (41) locations and in space.
    As the Earth orbits the Sun, it receives (42) approximately 1,400 watts per square meter of energy, as (43) measured upon a surface kept normal at a right angle to the Sun. This number is referred to as the solar constant. Of the energy received, roughly 19% is absorbed by the atmosphere, (44) while clouds on average reflect a further 35% of the total energy. The generally accepted standard is 1,020 watts per square meter at sea level.
    (45) After passing through the Earth’s atmosphere , most of the sun’s energy is in the form of visible light. Plants use solar energy to create chemical energy through photosynthesis (光合作用). (46) We use this energy when we burn fossil fuels or when we consume the plants as a source of food.