How Long Is A Kilowatt

Have you ever wondered just how long a kilowatt-hour is? Quantities designated by familiar measures such as the foot, pound, or cup can be easily appreciated because they can be seen.

Not surprisingly, few people can appreciate the quantity described by the measure called a kilowatt-hour. The commodity is invisible.

In order to visualize a kilowatt-hour (kWh), let's relate to the amount of work done by a person.

  • In the home, a person would have to beat a batter mixture at an incredible speed, steadily for 10 hours to generate energy equal to one kWh.
  • A person working steadily with a hand pump for one hour can pump 4,000 gallons of water out of a 25 foot well. A one kW motor running for one hour pumping out of a 25 foot well will pump 10,000 gallons.

Using these comparisons, it is obvious electricity is still the biggest bargain in anyone's budget.

 

TO CHANGE

TO

MULTIPLY BY:

1.

Kilowatts (kW)

Watts (W)

1000

2.

Horsepower (hp)

Watts (W)

746

3.

Kilowatts (kW)

Horsepower (hp)

4/3

4.

Horsepower (hp)

Kilowatts (kW)

¾

 

TO CHANGE

TO

DIVIDE BY:

5.

Watts (W)

Kilowatts (kW)

1000

6.

Watts (W)

Horsepower (hp)

746

A meter that records kilowatt-hours measures electricity use. A kilowatt-hour is 1,000 watts of electricity used for one hour.

A motor is a device that uses electric power and converts this power into the mechanical power of a rotating shaft. The electric power supplied to a motor is measured in watts or kilowatts; the mechanical power delivered by a motor is measured in horsepower. One horsepower is equivalent to 746 W of electric power.

You can calculate how much electricity an appliance uses by following this formula (using the example of a 50-watt radio "on" for 100 hours a month):

  • Check the wattage. (50 watts)
  • Multiply wattage by the number of hours appliance is used for a given period of time. (50 X 100=5,000)
  • Divide by 1,000 to get your answer in kilowatt-hours.(5,000 X 1,000= 5kwh)
  • When, to compute the monthly cost of operating the appliance, simply multiply the number of kilowatt-hours by the current electric rate (C.B.E.C, it's 7.439 cents per kilowatt-hour).(5 X .07439=.38)
  • It costs only 38 cents to operate a 50-watt radio for 100 hours each month!