When electricity flows through a wire, some of its energy goes into heating up the wire. Sometimes this is a problem. When electricity travels from a power station to the city, heat energy is wasted. But once the electricity arrives at your house for the purpose of heating a stove or a room, electrical heating is very efficient and flexible. What devices in your house use electricity for heating? Make a list in Notes on your handheld computer.

The Genecon is a little generator with the same basic design as the huge generators run by hydroelectric dams, coal-fired boilers, or nuclear power plants. In every case, some other form of energy (e.g., falling water, burning coal, decaying radioactive material) turns the "crank" of a generator and creates electrical power. In this case, you supply the power. Think of several ways that electric power is generated and the source of energy in each case. Make a list in Notes on your handheld computer.