Ch 16 and 17 vocabulary

active solar heating system
System that uses solar collectors to capture energy from the sun and store it as heat for space heating and water heating. Liquid or air pumped through the collectors transfers the captured heat to a storage system such as an insulated water tank or rock bed. Pumps or fans then distribute the stored heat or hot water throughout a dwelling as needed.
biofuel
Gas or liquid fuel (such as ethyl alcohol) made from plant material (biomass).
breeder nuclear fission reactor
Nuclear fission reactor that produces more nuclear fuel than it consumes by converting nonfissionable uranium-238 into fissionable plutonium-239.
cogeneration
Production of two useful forms of energy, such as high-temperature heat or steam and electricity, from the same fuel source.
energy conservation
Reducing or eliminating the unnecessary waste of energy.
energy efficiency
Percentage of the total energy input that does useful work and is not converted into low-quality, usually useless heat in an energy conversion system or process.
fissionable isotope
Isotope that can split apart when hit by a neutron at the right speed and thus undergo nuclear fission. Examples are uranium-235 and plutonium-239.
geothermal energy
Heat transferred from the earth’s underground concentrations of dry steam (steam with no water droplets), wet steam (a mixture of steam and water droplets), or hot water trapped in fractured or porous rock.
hydroelectric power plant
Structure in which the energy of falling or flowing water spins a turbine generator to produce electricity.
kilowatt (kW)
Unit of electrical power equal to 1,000 watts.
life-cycle cost
Initial cost plus lifetime operating costs of an economic good.
meltdown
The melting of the core of a nuclear reactor.
nuclear fission
Nuclear change in which the nuclei of certain isotopes with large mass numbers (such as uranium-235 and plutonium-239) are split apart into lighter nuclei when struck by a neutron. This process releases more neutrons and a large amount of energy.
nuclear fusion
Nuclear change in which two nuclei of isotopes of elements with a low mass number (such as hydrogen-2 and hydrogen-3) are forced together at extremely high temperatures until they fuse to form a heavier nucleus (such as helium-4). This process releases a large amount of energy.
passive solar heating system
System that captures sunlight directly within a structure and converts it into low-temperature heat for space heating or for heating water for domestic use without the use of mechanical devices.
photovoltaic cell (solar cell)
Device that converts radiant (solar) energy directly into electrical energy.
radioactive waste
Waste products of nuclear power plants, research, medicine, weapon production, or other processes involving nuclear reactions. See radioactivity.
solar collector
Device for collecting radiant energy from the sun and converting it into heat.
watt
Unit of power, or rate at which electrical work is done.
wind farm
Cluster of small to medium-sized wind turbines in a windy area to capture wind energy and convert it into electrical energy.