Friedland, Environmental Science for AP® Course, 4E, Unit 6

Active solar energy

A use of technology that captures and stores the energy of sunlight with electrical equipment and devices.

Radioactivity

The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.

Carbon monoxide

A colorless, odorless gas that is formed during incomplete combustion of most materials.

Energy quality

The ease with which an energy source can be used to do work.

Volatile organic compounds (VOCs)

An organic compound that evaporates at typical atmospheric temperatures.

Smart grid

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

Ethanol

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

Fuel cell

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

Siltation

Sediments from moving water that accumulate on the bottom of a reservoir.

Wind energy

Energy generated from the kinetic energy of moving air.

Hubbert curve

A graph that represents oil use and projects both when world oil production will reach a maximum and when world oil will be depleted.

Thermal mass

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

Photovoltaic solar cells

A use of energy from the Sun as light, not heat, and converting it directly into electricity.

Passive solar design

Construction technique designed to take advantage of solar radiation without active technology.

Potentially renewable

An energy source that can be regenerated indefinitely as long as it is not overharvested.

Control rod

A cylindrical device inserted between the fuel rods in a nuclear reactor to absorb excess neutrons and slow or stop the fission reaction.

Energy return on energy investment (EROEI)

The amount of energy we get out of an energy source for every unit of energy expended on its production.

Crude oil

A mixture of hydrocarbons such as oil, gasoline, kerosene as well as water and sulfur that exists in a liquid state underground, and when brought to the surface.

Cogeneration (Combined heat and power)

The use of a fuel to both generate electricity and deliver heat to a building or industrial process.

Tidal energy

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

Radioactive decay

When a parent radioactive isotope emits alpha or beta particles or gamma rays.

Biomass

Biological material that has mass.

Natural gas

A relatively clean fossil fuel containing 80 to 95 percent methane (CH4) and 5 to 20 percent ethane, propane, and butane.

Peak demand

The greatest quantity of energy used at any one time.

Oxygenated fuel

A fuel with oxygen as part of the molecule.

Peak oil

The point at which oil extraction and use would increase steadily until roughly half the supply had been used up.

Run-of-the-river

Hydroelectricity generation in which water is retained behind a low, small dam or no dam.

Nitrogen oxides

A by-product of combustion of any fuel in the atmosphere (which contains 78 percent nitrogen).

Fossil fuels

Fuels derived from biological material that became fossilized millions of years ago.

Electrical grid

A network of interconnected transmission lines.

Capacity factor

The fraction of time a power plant operates in a year.

Ground source heat pump

A technology that transfers heat from the ground to a building.

Phantom loads

Electrical demand by a device that draws electrical current, even when it is turned off.

Nonrenewable energy resource

An energy source with a finite supply, primarily the fossil fuels and nuclear fuels.

Half-life

The time it takes for one-half of an original radioactive parent atom to decay.

Geothermal energy

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

Peat

A precursor to coal, made up of partly decomposed organic material, including mosses.

Electrolysis

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

Carbon neutral

An activity that does not change atmospheric CO2 concentrations.

Curie

A unit of measure for radiation, a curie is 37 billion decays per second.

Fission

A nuclear reaction in which a neutron strikes a relatively large atomic nucleus, which then splits into two or more parts, releasing additional neutrons and energy in the form of heat.

Fuel rod

A cylindrical tube that encloses nuclear fuel within a nuclear reactor.

Commercial energy sources

Energy sources that are bought and sold, such as coal, oil, and natural gas.

Water impoundment

The storage of water in a reservoir behind a dam.

Biodiesel

A diesel substitute produced by extracting and chemically altering oil from plants.

Fossil carbon

Old carbon contained in fossil fuels.

Nondepletable

An energy source that cannot be used up.

Lignite

A brown coal that is a soft sedimentary rock that sometimes shows traces of plant structure; it typically contains 60 to 70 percent carbon.

Fossil fuel combustion

The chemical reaction between any fossil fuel and oxygen resulting in the production of carbon dioxide, water, and the release of energy.

Fracking

Short for hydraulic fracturing, a method of oil and gas extraction that uses high-pressure fluids to force open existing cracks in rocks deep underground.

Biofuel

Liquid fuel created from processed or refined biomass.

Capacity

The maximum electrical output of something such as a power plant.

Nuclear power

Electricity generated from the nuclear energy contained in nuclear fuel.

Becquerel (Bq)

A measurement of the rate at which a sample of radioactive material decays; 1 Bq is equal to the decay of one atom per second.

Cellulosic ethanol

An ethanol derived from cellulose, the cell wall material in plants.

Carbon dioxide

A by-product of all combustion, carbon dioxide from biofuels contains modern carbon from woody material, rather than fossil carbon from fossil fuels.

Anthracite (Hard coal)

Contains greater than 90 percent carbon. It has the highest quantity of energy per volume of coal and the fewest impurities.

Energy carrier

An energy source such as electricity that can move and deliver energy in a convenient, usable form to end users.

Passive solar

A use of energy from the sun that takes advantage of solar radiation without active technology.

Wind turbine

A turbine that converts the kinetic energy of moving air into electricity.

Turbine

A device that can be turned by water, steam, or wind to produce power such as electricity.

Radioactive waste

Nuclear fuel that can no longer produce enough heat to be useful in a power plant but continues to emit radioactivity.

Bituminous coal (Asphalt)

A black or dark brown coal that contains bitumen. It typically contains up to 80 percent carbon.

Modern carbon

Carbon in biomass that was recently in the atmosphere.

Energy efficiency

The ratio of the amount of energy expended in the form you want to the total amount of energy that is introduced into the system.

Combined cycle

A feature in some natural gas–fired power plants that uses both a steam turbine to generate electricity and a separate turbine that is powered by the exhaust gases from natural gas combustion to turn another turbine to generate electricity.

Subsistence energy sources

Energy sources gathered by individuals for their own immediate needs including straw, sticks, and animal dung.

Charcoal

Woody material that has been heated in the absence of oxygen so that water and some volatile compounds are driven off.

Energy intensity

The energy use per unit of gross domestic product (GDP).

Hydroelectricity

Electricity generated by the kinetic energy of moving water.

Renewable energy resources

Sources of energy that are infinite.

Tar sands (Oil sands)

Slow-flowing, viscous deposits of bitumen or asphalt, mixed with sand, water, and clay.

Coal

A solid fuel formed primarily from the remains of trees, ferns, and other plant materials that were preserved 280 million to 360 million years ago.

Energy conservation

Methods for finding and implementing ways to use less energy.

Particulates (Particulate matter; Soot)

Solid or liquid particles suspended in the air.