The electrical energy calculator was created to support GreenLearning’s Energy Revealed program delivered by the Alberta Council for Environmental Education in Alberta.

Electricity

Kilowatt Hours

Why is this important?

When you turn on any electrical device, it uses electriciy and you are charged for the amount used. This amount varies greatly depending on the device and the length of time it is used. You need to know the unit of measure for electricity.

What’s a watt?

A watt (W) is the unit used to measure the flow of electricity.  Look at your device and find out the device use in watts. This hair dryer uses 1600W.

A watt is a very small unit so kilowatt is used most often.
1 Kilowatt (kW)= 1000 watts

Convert from watts to kilowatts by dividing by 1000.

1600 W = 1600/1000 = 1.6 kW

The total amount of electricity used depends on how long the device is on. The unit for this is kilowatt hour (kWh).
kilowatt hour = kW x hours

If the hair dryer is used for 4 minutes per day this amounts to:
4 minutes x 365 days
= 1460 minutes
= 1460 / 60 minutes per hour = 24.33 hours in a year.

In one year the hair dryer uses:

1.6 kW x 24.33 hours = 39 kWh

Environment

Greenhouse Gases

Why is this important?

The production of electricity produces by-products called greenhouse gases (GHGs).  These 7 gases cause changes in the upper atmosphere. Most climate scientists agree that the main cause of the current global warming trend is the over-production of GHGs.

GHG Emission Sources

Some sources of electricity production emit more GHGs than others.  Burning coal to generate electricity produces the highest GHGs and renewable energy sources produce almost no GHGs. In Alberta, electricity generates on average 0.82 kilograms of GHGs per kilowatt hour (.82 kg/kWh).

Save Energy, Save the Environment

Governments, businesses and citizens want to reduce GHGs emissions and the impacts of climate change.

Back to the hair dryer. It used 39 kWh in a year and in Alberta each kWh emits .82 kg GHG:

39 kWh x .82 kg/kWh = 32 kg GHG

Environment

Electricity Rates

Why is this important?

Electric bills can get very expensive. Everyone is trying to save money. Cost is a big motivating factor in energy conservation and efficiency.

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The regulated rate of electricity in Alberta is capped at 6.8 cents per kWh. Rates may differ for competitive retailers.

To run the hair dryer for one year costs:

39 kWh x $ .068 = $2.65