chapter 13 key terms

energy conservation

finding and implementing ways to use less energy

tiered rate system

a billing system used by some electric companies in which customers pay higher rates as their use goes up

peak demand

the greatest quantity of energy used at any one time

passive solar design

construction designed to take advantage of solar radiation without active technology

thermal mass

a property of a building material that allows it to maintain heat or cold

potentially renewable

an energy source that can be regenerated indefinitely as long as it is not over harvested

nondepletable

an energy source that cannot be used up

renewable

in energy management, an energy source that is either potentially renewable or nondepletable

biofuel

liquid fuel created from processed or refined biomass

modern carbon

carbon in biomass that was recently in the atmosphere

fossil carbon

carbon in fossil fuels

carbon neutral

an activity that does not change atmospheric CO2 concentrations

net removal

the process of removing more than is replaced by growth, typically used when referring to carbon

ethanol

alcohol made by converting starches and sugars from plant material into alcohol and CO2

biodiesel

a diesel substitute produced by extracting and chemically altering oil from plants

flex-fuel vehicle

a vehicle that runs on either gasoline or a gasoline/ethanol mixture

hydroelectrcity

electricity generated by the kinetic energy of moving water

run-of-the-river

hydroelectricity generation in which water is retained behind a low dam or no dam

water impoundment

the storage of water in a reservoir behind a dam

tidal energy

energy that comes from the movement of water driven by the gravitational pull of the Moon

siltation

the accumulation of sediments, primarily silt, on the bottom of a reservoir

active solar energy

energy captured from sunlight with advanced technologies

photovoltaic solar cell

a system of capturing energy from sunlight and converting it directly into electricity

wind energy

energy generated from the kinetic energy of moving air

wind turbine

a turbine that converts wind energy into electricity

geothermal energy

heat energy that comes from the natural radioactive decay of elements deep within Earth

ground source heat pump

a technology that transfers heat from the ground to a building

fuel cell

an electrical-chemical device that converts fuel, such as hydrogen, into an electrical current

electrolysis

the application of an electric current to water molecules to split them into hydrogen and oxygen

smart grid

an efficient, self-regulating electricity distribution network that accepts any source of electricity and distributes it automatically to end users