Energy use for air conditioning roughly double between 1990 and 1993. In most areas of the country, solar water heating now costs about the same as electric water heating. More than half of U.S. households have a personal computer. More than two-thirds of U.S. households have an automatic washing machine and a clothes dryer. Always use cold water when flushing food down a kitchen garbage disposal.
Transportation accounts for one-half of all U.S. petroleum consumption.
But more homes are converting to central air conditioning. The setting uses 3 to 7 gallons of water each time you use it, up to half of the water of a full 14 gallon wash cycle. Grease solidifies in cold water and can be ground up and washed away. Since you won't have to heat the water, you'll be using less energy. Return to Percy's Puzzles.