kW vs. kWh: What's the Difference?

A kilowatt-hour measures the energy an appliance uses in kilowatts per hour. For example, if you clean your floors with a 1,000-watt vacuum cleaner for one hour, you consume 1 kWh of energy.

Let’s go over a few examples of kW vs kWh in the context of low- and high-power appliances:

• Lower watts : If you are using a 100-watt device, such as a plasma TV, you would have to watch your favorite shows for 10 hours before reaching 1 kWh.
• Higher watts : If you are running a 2,000-watt appliance, such as a clothes dryer, you only need to power it for 30 minutes to reach 1 kWh.

Let’s use a 1500W dishwasher you use for two hours per day as an example for calculating kW and kWh on a monthly basis:

1. Divide the wattage by 1,000 to calculate kW: 1500 watts / 1,000 = 1.5 kW
2. Multiply the kilowatts by the hours of daily use: 1.5 kW X 2 hours = 3 kWh per day
3. Find the total energy usage for a month (30 days): 3 kWh X 30 days = 90 kWh per month

For this example, we’ll say it’s $.07 per kWh:

• 90 kWh X $.07 per kWh = $6.30 per month

Utility companies measure your kWh with digital meters right outside of your home where the power line goes into the property.

While traditional meters require a utility service to come to your home, newer digital meters have an electronic display that uses a high-frequency signal to send data to the utility companies.

Now that you have a better understanding of kW versus kWh, and the different uses of electricity, you can take a closer look at your bill and begin to analyze your energy consumption. For a more detailed understanding, consider investing in a home energy monitor.

Many monitors available today are wireless and display your home’s energy consumption in an app. Depending on which monitor you choose, you may even be able to turn appliances on and off when you’re away from home using the app.

You can lower your electricity bill by following some easy energy-saving practices:

• Replace incandescent lightbulbs with energy-saving LEDs.
• Unplug or turn off appliances if you’ll be away from home for a few days, and resist the urge to leave your devices on standby when you don’t need them.
• Look into buying smart power bars for parts of your home with several electronic devices.
• You can set a timer on a smart power bar so that it automatically turns off power to the devices overnight.
• Turn off the lights whenever you leave a room.