Learning Objectives

1. Students will learn the connection between energy use and global climate change
2. Students will learn that different appliances and technologies with similar output vary in the amount of energy they consume
3. Students will identify and list technologies and other practical ways to be more energy efficient in a home
4. Students will build or display an apparatus or energy-efficient device that demonstrates its practical application for energy efficiency
5. Students will compare the relative value of an energy-efficient product or practice versus an equivalent product or practice that uses energy less efficiently, and use specific data, facts, and ideas to support their findings
6. Students will convey information and ideas from primary and secondary sources accurately and coherently
7. Students will report information and convey ideas logically and correctly

Teaching Process

1.Brainstorm with students how energy is wasted in homes and how they might help stop the waste. Students will do Internet research on current methods recommended for home energy efficiency. Students may also contact local energy specialists in the community and interview them about methods and/or technologies that would reduce energy waste, save money and prevent greenhouse gas emissions. These specialists may also provide testing equipment for the project.

2.Conduct the following demonstration project in class using a thermometer and lamp (or watt meter comparator), and one each of a CFL and incandescent bulb that produce equivalent lumens (light levels). A 60 watt incandescent bulb and a 13 watt CFL will generally produce equivalent light levels.

Have an adult place the CFL bulb in the lamp (or watt meter) and turn it on. Observe the light that is produced. Then, hold a thermometer six inches above the bulb for one minute and record the temperature. Turn off the lamp and let the bulb cool. Have an adult remove the CFL bulb, place the incandescent bulb in the lamp and turn it on. Observe the light that is produced. Again, hold a thermometer six inches above the bulb for one minute and record the temperature. Ask the students if they could tell any difference in how much light the two bulbs produced, which bulb produced more heat than the other, and which bulb is more energy efficient.

3.Have the class compute the actual electricity consumption of the two bulbs for varying time periods of use; have the students approximate how long they leave lights on (i.e. one hour of use, how many times a week, how much over the year). Have the students compare the amount of electricity used for the two bulbs for similar amounts of time. Compare the life cycle costs of the two bulbs based on the cost of electricity consumed and the purchase price of the bulb. Have the students compare the amount of amount of greenhouse gases produced based on the electricity consumed.

Electricity used (kWh) = hours of use x (wattage of bulb divided by 1000)

Cost = kWh x electric rate

Lifecycle costs = bulb price + lifetime electricity costs = bulb price + (electric rate x bulb lifetime x wattage of bulb / 1000) *CFL lifetime is 6,000 hours

*Incandescent bulb life time is 750 hours, so it takes 8 incandescents for every 1 CFL

Greenhouse Gas Emissions (pounds of pollution) = kWh x 1.58 pounds/kWh