The calculator is known to us. Calculators are meant to be called calculators. A small notebook type object that has a display unit. This display section shows the number of computation results or counters. Most of the calculators currently use digital and eca LCD screen. They have power or battery and very little. It can be seen that the watt is written behind the calculator, which is 0.004 or something more than that means that the cost of 1 percent of 1 watt of 1 watt is 4 percent of the current / ampea. That means 1/3 years to finish 1 good pencil battery.