How much energy does a calculator use?

Question

just want to know for a project =)

Answer 1

Mine is solar powered, so I'm guessing not much.

Answer 2

The power is in milli watts, naturally energy requirment will be in milli watt hours

Answer 3

You should be very suspicious of people who are answering this question in units of watts (or no units at all), as watts are a unit of power, not energy.  Power is the time derivative of energy.

You asked, "how much energy does a calculator use?"  The answer is the power consumption (watts) of the calculator times its duration of use.  For example, my scientific calculator is rated at 200 microwatts (0.0002 watts).  If I use it for one second, it will consume 200 microjoules (0.0002 joules) of energy.  That is a vanishingly small amount of energy.  If that energy were obtained via the electric mains rather than from a battery, the calculator could be run for approximately 38 years on US$0.01 worth of electricity.  As another illustration, the amount of energy needed to run a 100-watt light bulb for one second would run my calculator for almost 139 hours.

Answer 4

The LED calculators use much less than the old ones that used red lights to make the numbers.

Answer 5

It depends on the calculator.  Check the back of it or in the battery compartment.

Answer 6

A modern hand held calculator with a LCD display uses so little power that I am tempted to call it essentially zero. It can run for months on the smallest battery. Even at only 1 Watt, that small battery would be drained dead in less than one hour, so the calculator must be using much less than 1/1000 of a Watt.