vocab 6

biofuel

gas (such as methane) or liquid fuel (alcohol or biodiesel) made from plant material (biomass)

bitumen

gooey, black, high-sulfur, heavy oil extracted from tar sand and then upgraded to synthetic fuel oil

coal

solid, combustible mixture of organic compounds with 30-98% carbon by weight, mixed with various amounts of water and small amounts of sulfur and nitrogen compounds. it forms in several stages as the remains of plants are subjected to heat and pressure over millions of years

cogeneration

production of two useful forms of energy, such as high-temperature heat or steam and electricity, from the same fuel source

convergent boundary

area where the earth’s lithospheric plates are pushed together

cost-benefit analysis

a comparison of estimated costs and benefits of actions such as implementing a pollution control regulation, building a dam on a river, or preserving an area of forest

crude oil

gooey liquid consisting mostly of hydrocarbon compounds and small amounts of compounds containing oxygen, sulfur, and nitrogen. extracted from underground accumulations, it is sent to oil refineries, where it is converted to heating oil, diesel fuel, gasoline, tar, and other materials

divergent boundary

area where the earth’s lithospheric plates move apart in opposite directions

energy efficiency

percentage of the total energy input that does useful work and is not converted into low-quality, generally useless heat in an energy conversion system or process

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

half-life

the time it takes for 1⁄2 of the mass of a radioisotope to decay

hot spots

volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the mantle elsewhere

hydraulic fracturing

freeing oil or natural gas that is tightly held in rock deposits by using perforated drilling well tubes with explosive charges to create fissures in rock and then using high pressure pumps to shoot a mixture of water, sand, and chemicals into the well to hold the rock fractures open and release the oil or natural gas, which flows back to the surface along with a mixture of water, sand, fracking chemicals, and other chemicals that are released from the rock

hydropower

electrical energy produced by falling or flowing water

isotopes

two or more forms of a chemical element that have the same number of protons but different mass numbers because they have different numbers of neutrons in their nuclei

natural gas

underground deposits of gases consisting of 50-90% by weight methane gas (CH4) and small amounts of heavier gaseous hydrocarbon compounds such as propane (C3H8) and butane (C4H10)

nonrenewable resources

resource that exists in a fixed amount in the earth’s crust and has the potential for renewal by geological, physical, and chemical process taking place over hundreds of millions to billions of years (copper, aluminum, coal, + oil). we classify these resources as exhaustible because we are extracting and using them at a much faster rate than they are formed

nuclear fuel cycle

includes the mining of uranium, processing and enriching the uranium to make nuclear fuel, using it in the reactor, safely storing the resulting highly radioactive wastes for thousands of years until their radioactivity falls to safe levels, and retiring the highly radioactive nuclear plant by taking it apart and strong its high level radioactive material safely for thousands of years

photovoltaic cell (pv)

device that converts radiant (solar) energy directly into electrical energy. also called a solar cell

radioactivity

nuclear change in which unstable nuclei of atoms spontaneously shoot out “chunks” of mass, energy, or both at a fixed rate.

refining

complex process in which crude oil is heated and vaporized in giant columns and separated, by use of varying boiling points, into various products such as gasoline, heating oil, and asphalt

renewable resource

resource that can be replenished rapidly (hours-decades) through natural processes as long as it is not used up faster than it is replaced. (trees, grasses, animals, fresh water, fresh air, fertile soil)

rift valleys

a large elongated depression with steep walls formed by the downward displacement of a block of the earth's surface between nearly parallel faults or fault systems.

seafloor spreading

the formation of new areas of oceanic crust that occurs through the upward motion of magma at midocean ridges and its outward movement on either side

solar thermal system

system that uses any of various methods to collect and concentrate solar energy in order to boil water and produce steam for generating electricity

thermal pollution

occurs when heat released into the water produces negative effects to the organisms in that ecosystem

transform boundary

area where the earth’s lithospheric plates move in opposite but parallel directions along a fracture in the lithosphere

turbines

a device with blades that can be turned by water, wind, steam, or exhaust gas from combustion that turns a generator in an electricity-producing plant

wind farm

cluster of wind turbines in a windy area on land or at sea, built to capture wind energy and convert it into electrical energy