CBSE Class 10 Answered

Of the total solar energy reaching the earth's surface, about 30% is reflected from clouds, water and land surfaces. 60% is absorbed and goes into heating land, water and air. Only 10% of the solar energy is absorbed by vegetation. Since the efficiency of photosynthesis is low, only 2-5% of the 10% absorbed by vegetation (which amounts to 0.2-0.5% of the total solar energy) is trapped as biomass at the first trophic level, but it is this latter amount of energy that supports all the rest of the ecosystem. It is estimated that just 0.1% of the solar energy being harnessed to  perform useful work would supply all human needs.