We use electricity for many activities at home, such as drying clothes, cooking food, and heating and cooling. The total amount of energy that we use depends both on how much energy each individual appliance consumes and on how long we use the appliance each day. In this lab, you will survey your household to determine how much electricity you consume and you will analyze an electric bill to calculate how much you pay for your electricity.

OBJECTIVES

Identifythe ways in which electricity is consumed in your household.

Computethe energy consumption of your household.

Interpretan electric utility bill and an electric meter.

MATERIALS

calculator, electric bill, notebook, pen or pencil

PROCEDURE

1. Walk through or think about your home, and identify all appliances and devices that use electricity. Add any  item not included in the table below. Begin to fill out the table. (10 points)

IMPORTANT:

Fill in ALL columns unless you do not have that appliance. For column c, do your best to estimate the amount of time the item is used in your home. For this lab, assume the item is being used on this particular day. 

*for the hours used per day column you can use decimals too: 1minute  = 0.017 hours. Like my coffee maker brews for 12 minutes, so 12 X 0.017 = 0.2 hours.

** for things like chargers and gaming systems, if they're plugged in they're drawng power (even if your not charging anything)

*** a fridge and hot water heater each run for 4-5 hours per day (more for the hot water heater if you use a lot of hot water in your home)

****for the light bulbs - count ALL bulbs in your home and guesstimate how long they're on for in each room.

2. For column (d), determine daily energy consumption in kilowatt-hours by dividing the wattage of an appliance (found in the table in column (b)) by 1,000,  then multiply by the number of hours the item isused per day.  So the equation would look like this:

       (b) / 1000 X (c) = (d)

ANALYSIS

1. Add up the energy consumption per day for all items. This number is the total energy consumed by your household in one day. (3pts)

2. On your electric bill (or the sample electric bill provided), find the total number of kilowatt-hours consumed during this time period. An electric bill usually lists a meter reading for the beginning of the time period and for the end of the time period. The difference is the energy consumption in kilowatt-hours. (3pts) if using the sample bill. Look for the letter "J." Then do "J" pres - "J" prev

3. Divide the number of kilowatt-hours from the electric bill by the number of days in the time period. This number reflects the average daily energy consumption for this time period. (3pts) take the answer from #2 and divide by the number of days in the month, which can be found using letter "O" on the electric bill

4. Compare the daily energy consumption that you calculated from your home survey with the average calculated from the sample electric bill. Is there a difference between your home and the "typical American home"? If so, what could explain the difference (describe and be as specific as possible)? (5pts) hint: compare yours (#1) to the sample (#3). Is yours higher or lower? What could explain yours being different? For example, are there a lot of people in your home, are a lot of lights left on, do you do 4 loads of laundry per day, do you watch hours and hours of television, etc?

5. If the price of electricity is $0.16 per kilowatt-hour, how much does doing a load of laundry cost (washing your clothes in a washing machine then drying them in the dryer )? (3pts)

CONCLUSIONS

6. What can you conclude about energy consumption in your home (like is it high or low or average)? Explain. What activities consume the most energy? Describe 3-5 ways you could reduce the energy consumption in your home. (5pts)

7. Here's how the electric company does it: the meter readers comes to your home and looks at your electric meter at the the start and end of each billing cycle. Then an estimate is made and you are billed accordingly. In your opinion, do you feel like this is an accurate representation of your usage (why or why not)? Could it be refined to more closely estimate your daily energy consumption? (3pts)

Extension (EXTRA CREDIT)

1. Communicating Ideas Even when an appliance is turned off, it can still consume electricity. This type of electricity consumption is called a phantom load. Find out about phantom loads and prepare a booklet that shows how people can reduce this type of energy use.