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INVESTIGATION: Efficiency of household appliances

Lesson

Energy ratings

In Australia, an energy rating label is provided for various appliances, such as refrigerators, televisions, dishwashers, and air conditioners. The label tells you how much energy an appliance will use in a year and the star rating tells you how energy efficient the appliance is. The more stars, the more energy efficient an appliance is. This is particularly important as the world starts to feel the effects of climate change because electricity consumption is one of the largest contributors to carbon emissions into the atmosphere. As well as being better for the environment, more energy efficient products are cheaper to run because they use less electricity.

The number in the red box is the energy consumption measure of the product, expressed in kilowatt-hours. The number corresponds to the amount of electricity (kWh) the appliance will use over the course of a year. 

Energy Rating Label (Source: www.sa.gov.au)

The lower the number in the red box the less it will cost you to run. The higher the number of stars, the more energy efficient the appliance is.

 

Money Matters

In a perfect world, we would all use the most energy-efficient products. However, appliances with better energy ratings are often more expensive to purchase. Have a look at the example of similar washing machines in the table below:

Prices and specifications taken from www.harveynorman.com.au (October 2013)

Investigation

Find the energy rating for your fridge, washing machine, dryer, television and air conditioner and rank them in order of efficiency.

Use the Internet to find similar products with better energy ratings.

Compare the savings of a more efficient appliance over the course of a year. How long before the higher purchase price is compensated by savings?

Discuss whether prices on more energy efficient items will reduce or increase over the next five years. What are some of the factors that will impact the price of more energy efficient products?

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