Lesson 4.5: Energy Investigation

Lesson 4.5: Energy Investigation

How much electricity do you use in a month, in a year?  You have to read the electric meter or examine an electric bill to get that information.  

Read the investigation Energy Efficiency in the Home on page 147 before you answer the following questions. 

Question 1. How many kW·h does an average Canadian household use in a year? 

Question 2. Look at the electrical energy bill in the investigation.  Estimate how many kW·h this household used in 2000 and in 2001.   

Question 3. How does this electricity consumption compare from the year 2000 to the year 2001?  Try to think of some reasons for the difference.

Question 4. How does this electricity consumption compare to that of the average Canadian household?  Try to think of some reasons for the difference.

Question 5. Explain why more electricity is used in the winter months than in the summer months.

 

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. How many kW·h does an average household use in a year?

The text reading indicates a Canadian average of 39 200 kW·h per year.

Question 2. Look at the electrical energy bill in the investigation.  Estimate how many kW·h this household used in 2000 and in 2001.

The estimate for 2001 is 1500 + 1000 + 750 + 600 + 900 + 1250 = 6000 kW·h.
The estimate for 2000 is 1400 + 1100 + 900 + 700 + 1000 + 1400 = 6600 kW·h.

Question 3. How does this electricity consumption compare from the year 2000 to the year 2001?  Try to think of some reasons for the difference.

There is a difference of 600 kW·h. Less electricity was used in 2001 than in 2000.  Some possible reasons could be
- they purchased more energy efficient appliances and lights
- the people became energy conscious and are conserving

Question 4. How does this electricity consumption compare to that of the average Canadian household?  Try to think of some reasons for the difference.

There is a huge difference; the average is 39 200 kW·h per year. This bill is for only 6000 kW·h in the year 2001.  This is less than one sixth of the average.  The most likely reason is that the text says that 39 200 kW·h of energy, not just electricity.  This would include the natural gas and other fossil fuels used to heat homes and drive vehicles.  This would most likely be the reason for the large difference.

Question 5. Explain why more electricity is used in the winter months compared to the summer months.

Several reasons are possible.  There are far fewer daylight hours in the winter compared to the summer, so the lights are on much longer in winter.  The furnace fan has to work to circulate the heat in the winter; the furnace is not used in the summer.  Cars have to be plugged in on very cold days.  You may have some other possible reasons as well.   

Click on the page forward to continue Lesson 4.

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