surface mining
removing shallow deposits such as nonfuel mineral and rock resources and 60% of US coal
overburden
giant mechanized equipent strips away overburden of soil and rock
spoils
the equipment strips away overburen and discards it as wastw-spoils
strip mining
used for extracting mineral deposits that lie close to the earth's surface in large horizontal beds. often used to extract coal
area strip mining
used in flat terrain. giant machines remove overburden, them power shovels are used to remove mineral deposits
spoil banks
exposed areas of gravel and rock tat are very prone to erosion and runoff
contour strip mining
used on mountainous terrain
highwall
contour strip mining-unless the land is restored, a wall of dirt is left in front of a highly erodible bank
open-pit mining
used to create large pits to extract iron, copper, sand, gravel, and stone. toxic groundwater can accumulate at the bottom
mountaintop removal
machinery removes the top of mountains to expose coal. the resulting waste rock and dirt are dumped into the streams and valleys below
acid mine drainage
occurs when rainwater seeping through a mine carries sulfuric acid to nearby streams and groundwater (acid is produced by aerobic bacteria in sulfur in spoils) - can destroy aquatic life
ore
material that is extracted from the ground
ore mineral
desired mineral
gangue
waste material after the desired metal is extracted
tailing
piles of solid waste left over from ore mineral removal
smelting
process of heating ores to remove metals
cyanide heap extraction
involves spraying toxic cyanide salts on heaps of crushed ore, where it reacts with the material and separates the gold from the ore
Surface Mining Control and Reclamation Act of 1977
requires mining companies to restore most surface-mining land by grading and replanting it
commercial energy
energy that is sold as electricity, gasoline, or other types of fuel
nonrenewable commercial energy
comes from extracting and burning nonrenewable mineral resources from the earth's crust
net energy
amount of high-quality energy that is available to be used from a resource after subtracting the energy needed to make it usable
Second Law of Thermodynamics
energy is lost at each step
crude oil (petroleum)
a thick liquid hydrocarbon that is extracted from underground deposits and separated into a wide variety of products
hydrocarbons
made of long chains of carbon atoms bonded together and also bonded to hydrogen, as well as smaller amoutns of sulfur, oxygen, and nitrogen
peak production
of a well passes when the pressure starts to delcine and more and more energy is expended to get oil to the surface
heavy crude oil
is too heavy to extract, but in times of need can be flushed with water and removed (but usable energy is lowered)
petrochemicals
extracted include pesticides, plastics, synthetic fibers for fabric, paints, medicines, and many types of fuel
OPEC
Organization of Petroleum Exporting Countries - Algeria, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, the U.A.E, and Venezuela
natural gas
mixture of gases, with a majority of methane, also contains ethane, propane, butane, and hydrogen sulfide
liquefied petroleum gas (LPG)
the propane and butane gases after they have been removed from the natural gas mixture and liquefied
unconventional natural gas
includes coal bed methane gas and methane hydrate
coal bed methane
found above coal beds and is usually helped in place by pressure from aquifers, thich have to be pumped to release the gas
methane hydrate
methane trapped in water ice crystals, but in order to be used as fuel it needs to be liquefied. releasing methane as a gas instead bad-extremely strong greenhouse gas
coal
solid fossil fuel that is formed in several stages as the buried remains of land plants that lived 300-400 million years ago. mostly carbon but some sulfure impurities
anthracite
most desirable form of coal because it has a high heat content (high net energy yield) and a low sulfur content
coal gasification
process behind the concept of "clean coal", and is designed to remove carbon dioxide from the emissions produced by burning coal and turn coal into liquid gas fuel
nuclear energy
when isotopes of uranium and plutonium undergo controlled nuclear fission, the resulting heat produces steam that spins turbines to generate electricity
light-water reactors
cores contain fuel rods packed together in fuel assemblies and contain the potential energy of 100 tons of coal
moderators
nuclear reactors used moderators to slow down the neutrons emitted by fission process
coolants
usually water, circulates through the reactor core to remove heat and keep materials from melting
containment vessels
concrete barriers that surround the reactor core and is designed to keep radioactive materials from escaping into the environment in case of a meltdown or an external threat
refueling process
occurs when a year-"spet" fuel rods that are now radioactive are sent to water-filled pools or dry casks that are more vulnerable to outside threats
high-level radioactive waste
consists of spent fuel rods and waste from weapons production
decommisioning
nuclear plants involves safely retiring old plants
gasoline-electric hybrid
used by Toyota Prius and other widely-sold hybrids. small traditional, gas-powered motor that shuts off at low speeds and stops. electric motor provides additional power when needed, heat energy generated during braking is recovered and converted to elect
plug-in hybrid
has a second battery that can be plugged in and recharged when the car is not being used. drawbacks-electricity used to recharge generated by fossil fuels and nuclear plants, but could use wind-power instead
electric-only
not a hybrid because it relies only on electricity.
fuel-efficient vehicles
powered by a fuel cell that runs on hydrogen gas. emits no air pollution or CO2 if hydrogen is produced from renewable-energy sources
passive solar heating
absorbs and stores heat from the sun directly within a structure without the need for pumps to distribute the heat
active solar heating
absorbing energy from the sun by pumping a heat-absorbing fluid (water or antifreeze) through roof-mounted collectors
strawbale
superinsulator that is made from bales of low-cost straw covered with plaster or adobe.
solar thermal system
collect and transform energy from the sun into high-temperature thermal energy (heat) and then converted into electricity
central receiver systems or "power towers
huge arrays of computer controlled mirrors called heliostates that track the sun and focus it on a collection tower
solar thermal plants
collect sunlight and focus it on oil-filled pipes running thorugh large ares of solar collectors
photovoltaic cells (solar cells)
convert solar energy directly into electrical energy. thin wafers of silicon with trace amounts of other metals that funstion as semiconductors. when sunlight strikes the cells, the metals emit electrons that flow and create an electrical current
hydropower
water flowing from higher to lower elevations in streams and rivers can be controlled by dams and reservoirs to produce electricity. solar energy-solar heating causes movement of water
tidal power
dams can be built across bays where tidal differences are large between high and low tide. flowing water spins turbines to create electricity
wave energy power
can also be used to spin turbines but very expensive
wind power
world's most promising energy resource because its is abundant, inexhaustible, widely distributed, cheap, clean, and emits no greenhouse gases. turbines have sensors and computers that allow them to turn into the wind to capture it most efficiently
biomass
burn it to produce heat or electricty, convert into gaseous or liquid biofuels to get energy. indirect source of solar energy because it consists of combustible organic compouns produced by photosynthesis
biofuels
liquid fuels that are produced from plants and plant wastes. mostly ethanol, methanol, and biodiesel
geothermal energy
consists of heat sotre in soil, underground rocks, and fluidds in the Eath's mantle
geothermal heat pump
can heat and cool a house using the difference between the surface and underground temperatures. problems: limited available sites