Kilowatt vs Kilowatt-Hour
If you have high electricity bills, then you might be looking for energy efficiency upgrades for your home. And while comparing various energy solutions and prices, you’ve heard the metric, kilowatt-hour (kWh), used incessantly. But you’ve probably never thought about the number of kilowatt-hours your home appliances are using.
The reality is, every appliance in your home uses electricity and eventually adds up to your monthly electricity bill. Which begs the question...what exactly a kilowatt-hour means and how it's different from a kilowatt.
The Kilowatt-Hour explained
A kilowatt is a metric that equals 1,000 watts of power. Wattage, in turn, indicates how much power a device can provide a relative amount of time. The easiest way to illustrate a kilowatt-hour is to use the example of a 100-watt light bulb:
The 100 watts refers to the power the light bulb draws from the grid any time it is on.
1 kilowatt-hour of energy equals to 1,000 watt-hours. Which is equivalent to lighting a 100 watt light bulb for 10 hours.
(100 watts x 10 hours = 1,000 watt‐hours = 1 kWh).
Believe it or not, a kilowatt-hour can go pretty far. Here are some examples of typical use of a single kWh:
‐ Watch television for 10 hours
‐ Wash 12 pounds of laundry
‐ Work on a laptop computer for 5‐10 hours
‐ Vacuum for one hour
Here are some examples to illustrate kilowatt-hour consumption by common household devices:
Ceiling Fan: 0.075 kWh/hr.
Central Air Conditioning (3 ton‐12SEER): 3.0 kWh/hr.
Portable Heater (1500W): 1.5 kWh/hr.
Dishwasher, Normal Cycle – Cold Water 1.0: 2.17 kWh/load
Oven, Microwave: 0.12 kWh/5 min
Energy Star Refrigerator (frost‐free), 17 Cu/Ft: 73.0 kWh/mo
Electric Iron: 1.0 kWh/hr.
Television >50” Plasma: 0.48 kWh/hr.
Television > 50" LCD: 0.22 kWh/hr.
Recording Device – DVR: 28.8 kWh/mo+ depending on the model
Computer – Laptop: 0.02 ‐ 0.05 kWh/hr.
iPhone 6: 3.8 kWh/per full year! (4.2 kWh iPhone 6+)
Golf Cart Batteries (48 Volt) - New: 2.8 kWh/per full charge (up to 10 kWh on old batteries)
Tesla Model S (P85D): 85 kWh/per full charge (3,400 kWh per year assuming 12,000 miles driven)
Become Energy Efficient!
Becoming energy efficient is a powerful way to save money and lower your electricity bills. Additionally, you’ll also lower the cost of your solar system since you'll need fewer panels to offset your usage. By understanding how kilowatt-hours correlate to your energy usage, it can lead to lasting benefits as you consider energy-efficient solutions for your home.