ap environmental science - unit 6: energy resources & consumption

active solar systems

use solar energy to heat a liquid through mechanical and electrical equipment to collect and store captured energy

anthracite

* black
* low sulfur content, high carbon content
* produces fewest pollutants
* highest heat capacity

biofuels

liquid fuels (ethanol, biodiesel) created from biomass

biomass

organic fuel sources that are easily accessible and are often used in developing countries as cooking fuel or home heating

ex. wood, charcoal

* wood is free/cheap but can cause deforestation and habitat loss
* charcoal is made by heating wood under low oxygen conditions for a long period of time

bitumen

thick, sticky, semi-solid form of petroleum

bituminous coal

* black
* high sulfur content, medium-high carbon content
* most common type of coal
* produces lots of heat

coal

a combustible black or brownish-black rock primarily composed of carbon

creation:

* areas of swampy wetlands with high primary production create organic matter quickly - faster than it can be decomposed
* layers of organic matter are accumulated and then buried
* heat & pressure from overlying rock and sediment layers compacts peat into coal over time

cogeneration

the simultaneous generation of electrical and thermal energy from a single fuel source

combustion of fossil fuels

reaction between hydrocarbons and oxygen that produces carbon dioxide and water as products and releases energy as heat

equation: CH4 + O2 → CO2 + H2O

concentrating solar-thermal power (csp)

means of producing electricity where the sun’s energy is concentrated by mirrors/lenses to heat a fluid.drive an engine

crude oil

decaying organic matter trapped under rock layers is compressed into oil over time

composed of hundreds of hydrocarbon compounds and separated by fractional distillation

extracted by drilling a well through the overlying rock layers to reach the underground deposit and then pumping liquid oil out under pressure or from tar sands

electricity generation process

1\.) burn fuel to create heat

2\.) use heat to boil water to create steam

3\.) use steam to turn the blade of a turbine

4\.) use the spinning motion to turn/spin an electrical generation

electrolysis

current applied to water, breaking into O2 and H2

ethanol

renewable fuel made of corn and/or sugar

flowback water

used fracking fluid

fractional distillation

form of distillation in which miscible (mixed) liquids are separated based on their boiling points

fission

nuclear energy released when atoms are split

flex fuel (e85)

51-83% ethanol + gasoline mix (used in flex-fuel vehicles) which decreases oil consumption for transportation, but is less efficient than pure gasoline

fusion

nuclear energy released when atoms are fused

geothermal energy

energy from earth’s interior for electricity or space heating

hydraulic fracturing

well stimulation technique in which rock is fractured by a pressurized liquid - recovers natural gas & oil from sedimentary rock

hydroelectric power

water flows with natural current of the river or tides or by falling vertically through channel in a dam

hydrogen fuel cell

H2 is used as a renewable fuel source to generate electricity

lignite

* dark brown
* medium sulfur content, low carbon content
* lowest quality
* soft
* produces little heat

mine tailings

leftover rock and soil from mining; may have radioactive elements that can contaminate water or soil nearby

natural gas

contains only methane, ethane, propane, and butane

used increasingly for electricity, transportation, and commercial cooling

considered the “cleanest” fossil fuel

expensive for international transport since natural gas has to be liquefied

nonrenewable sources

* exist in fixed amounts on earth and cannot be easily replaced/regenerated
* fossil fuels - fossilized remains of ancient biomass which took millions of years to form
* nuclear energy - generated from the mineral uranism or other radioactive materials

nuclear fission

occurs when 2 nuclides (like U-235 and a neutron) collide and produce new nuclides that are different from the ones that started the reaction

nuclear reactor parts

* reactor core: fission of U-235 occurs
* steam generator: produces steam from water
* water pump: brings in cool water to be turned into steam and also cools reactor down from overheating
* turbine: steam is used to turn the blades of the turbine
* generator: turning motion from turbine spins generator to create electric current
* condenser: cools steam to convert to liquid water
* cooling tower: allows steam from turbine to condense back into liquid and cool down before being reused

passive solar systems

absorbing/blocking the sun’s energy without the use of mechanical or electrical devices to distribute collected heat

peat

partially decomposed organic matter found in wet, acidic ecosystems (ex. bogs)

can be dried and used as biomass

photovoltaic cell (pvc)

semiconductor that emits low voltage electrical current when exposed to the sun

radioactivity

the energy given off by the nucleus of a radioactive isotope

renewable sources

* can be replenished naturally or at/near the rate of consumption and reused
* depletable - can run out if overused
* nondepletable - will not run out if overused

run of river (ror) hydropower system

a small dam/weir diverts the natural current of a river through man-made channel beside the river to power generating facility

subbituminous coal

* dull black
* low sulfur content, low carbon content
* low heat value

subsurface mining

extraction of mineral & energy resources from deep underground deposits

surface mining

extraction of mineral & energy resources from the surface (within 30 meters)

tar sands

bitumen deposits where crude oil can be recovered, but with higher water and energy inputs

thermal pollution

hot water from power plants released back into surface waters can cause thermal shock to aquatic species

tidal energy

uses the energy created by tidal flows to turn a turbine and generate energy

use of energy

higher in MDCs (more developed countries) than in LDCs (lesser developed countries) due to their complex industrialized bases, low rates of pop. growth, and high per capita incomes

water impoundment hydropower (dams)

dam built in a river creates a large artificial lake behind the dan (reservoir) that can control the amount of water through the channel, increasing/decreasing electricity production

wind power

moving air (kinetic energy) spins turbine blades (mechanical energy) and gears connect to generator producing energy (electric energy)