In his life and work, a person has always used force, expended his energy for different purposes: for movement, for carrying heavy loads, when hunting, when cultivating land, etc. However, human strength is not great. If we evaluate it, as is customary in the energy sector, with power, that is, work done in one second, then for an average person it will be only about 15 kilograms, that is, 200 times less than for a one and a half ton truck.