Overview
This activity is an extension of the electricity unit taught in the
eighth grade. As the students study about energy conversions involved
with electricity, they can also become involved in the usage of
energy in their homes. After the students collect information on
several home appliances, they create a spreadsheet to calculate the
energy output of each individual appliance and the total energy
output for all appliances. This information can then be converted
from hourly usage to cost per kilowatt hour and then put into a daily
or monthly cost analysis.
Concepts
- The spreadsheet is a useful tool for doing mathematical
calculations on multiple data items.
- Energy consumption can be monitored through individual
appliances.
- Cost analysis of home energy consumption can provide useful
information for conservation of electricity.
Indicators
- Research and record on a data chart the name of appliance,
power (kW) and time of usage (h).
- Create spreadsheet cells for the Name of Appliance, Power
(kW), Time of Usage (h), Energy (kWh), Average Hourly Cost, Daily
Cost and Monthly Cost.
- Use the spreadsheet to calculate the Total Monthly Cost of all
appliances.
- Analyze the hourly usage and cost of each appliance and apply
this analysis to future conservation.
Precomputer
- Discuss the many sources of electricity and the current
dependence on fossil fuels for electricity.
- Discuss the practical application of a home energy
inventory.
- Gather necessary data from a minimum of six appliances that
are commonly used in the home.
- Use a personal home electric bill to calculate the cost of a
kilowatt-hour.
On the computer:
- Set up a spreadsheet using the data collected from home. For
the energy (kWh), use the formula (energy (kWh) = power (kW) *
time (h)).
Postcomputer
- Analyze the monthly usage of each appliance and the total
usage of all appliances researched. Apply this analysis to the
future conservation of electricity.
- Analyze the cost of the appliance usage and discuss ways to
reduce the monthly electric bill.
Related resources
- Glencoe Physical Science, 1997.