Once upon a time, in a town not far away, there was an 8th grader who was afraid of the dark. Her name was Jules. She was also afraid of the quiet, and of the cold. So she always left on the lights, the TV, and stereo even when she had her I-Pod earbuds on. She took lots of very long, hot showers. She never walked anywhere, but got rides from her mom in a big SUV. She couldn't be happy unless she was using all the energy she possibly could for all the stuff around her.
Her friend, Les, didn't like to use any energy at all. He walked to school, read books instead of watching TV, played the trumpet instead of Guitar Hero, and turned off the lights anytime he left a room.
Then one evening, there was a power outage. The lights went out, the TV turned off, and everything became very quiet. Jules became very upset, and quite scared. She couldn't do anything that she wanted to do. She didn't think she could survive. Meanwhile, Les didn't seem to mind at all. He was able to light a few candles and he could still read his books, practice his trumpet, and hang out and play cards with his family.
The two friends then realized that there was a big difference in their lifestyles and the amount of energy they used. So Jules decided she should figure out how much energy Les used and then compare her energy consumption to how much she really needed. To do this, they figured out how much energy Jules was using for entertainment, light, heating and cooling, cleaning, preparing food, transportation, and communication devices. They discovered that the amount of energy used for any purpose could be measured in different ways. Light bulbs are measured in watts. Air conditioners and hot water heaters are measured in BTUs, while energy used by cars is measured in gallons of fuel.
They used a spreadsheet to figure out how much energy they consumed for each of their activities. Each of the lights, car miles, games, and other appliances was converted to a common unit of power consumption called kilowatt-hours. The spreadsheet was used to determine how many kilowatt-hours were used during each day, each week, and each year for each energy consumption activity. The spreadsheet converted their energy consumption to show them the amount of money it costs for each energy consumption activity. In the end, they were shocked to see how much money Jules' energy using habits cost compared to Les' habits.