CHAPTER 18

A system of putting the sun’s energy to use in which collectors absorb solar energy and pumps or fans distribute the collected heat.

Plant and animal material used as fuel.

An energy technology that involves recycling “waste” heat. ( combined heat and power)

Using less energy—by reducing energy use and waste, for example.

Using less energy to accomplish a given task–by using new technology, for example.

A device that directly converts chemical energy into electricity. A fuel cell requires hydrogen and oxygen from the air.

Energy from Earth’s hot interior, used for space heating or generation of electricity.

A form of renewable energy that relies on flowing or falling water to generate electricity

A system of putting the sun’s energy to use that does not require mechanical devices to distribute the collected heat.

A wafer or thin film of solid-state materials, such as silicon or gallium arsenide, that is treated with certain metals in such a way that the film generates electricity when solar energy is absorbed.

A means of producing electricity in which the sun’s energy is concentrated using mirrors or lenses onto a fluid-filled pipe; the heated fluid is used to generate electricity.

Electric energy obtained from surface air currents caused by the solar warming of air.