From the example When the practicality it may lose power. Therefore, it must find another way to make a minimal power consumption and can provide the maximum benefits.
By example When practically possible but may have lost a lot of energy. Therefore, we must find other ways of making a low power consumption and can provide the most benefit.
From the examples. When the actual can do but may lose a lot of energy Therefore, must find a way to other make consumption minimal energy and can make the maximum benefit.