APES Unit 6: Energy Resources and Consumption

Surface mining

if a resource is less than 200 feet from the surface, the topsoil and rock is removed. explosives used to break up rock. reclamation follows

overburden or spoils?

overburden: topsoil and rock above the thing that is being mined in surface mining

Spoils: the overburden when it is removed

benefits and drawbacks surface mining

+: cheap, easy, efficient

-: tears up land (temporarily) byproducts produce an acid that accumulates in waterways

Strip Mining

earthmover strips away overburden and a power shovel removes the mineral deposit. trench is filled with overburden. Leaves spoil banks

spoil banks

caused by strip mining. hills of mining waste susceptible to erosion, slow regrowth, no topsoil

contour strip mining

surface mining in a hilly area. shovel cuts terraces into hill, remove overburden and dump it into terrace below. wall of dirt is left in front of a highly erodible bank called a highwall

Mountain top removal

explosives remove the top of a mountain and expose seams. of coal. waste is dumped into valleys below, often blocking rivers and streams. “biggest of all the bummers”

Surface mining control and reclamation act of 1977

requires mining companies to resotre most surface mined land by grading and replanting it. Only partially successful bc it takes decades and arid land often ends up as a desert

underground/subsurface mining

digging a shaft down to the resource, using machinery and ppl to tear off and remove the resource

benefits and drawbacks to underground/subsurface mining

+: can get resources far underground, does not scar land

-: more expensive, more time, more dangerous

3 major impacts of mining

scarring and disruption of land surface, subsidence (cave ins), toxin laced mining waste/acid mine drainage

removing metal from ore

ore mineral is what you want, gangue is the waste material. removing ganue produces large piles of waste called tailings.

Smelting: roasts ores to release metals

cyanide heap extraction: separate gold from gold ore

which countries have the most coal?

US (22%), Russia (15%), australia (14), china (13%)

Peat

not considered coal yet, lots of moisture, not efficient

Lignite

Low heat and sulfur, Lame

Bituminous

Bad, high heat and sulfur

Anthoricte

A+, high heat, low sulfur

steps to light!

plant

compress

coal

mined

transported

power plant

crushed

set on fire

steam

wind turbine

generator

electricity

powerline

outlet/lights

gasification

turns coal into syngas

fluidized bed combustion

mixes crushed coal with limestone and sets them on fire. sulfur reacts with limestone to sulfur is removed so scrubbers are not needed. produced more heat but is costly

coal burning impacts

release CO2 into atmosphere (global warming), increases air pollution, contains mercury (harms humans and wildlife), releases nitrogen oxides and sulfur oxides (acid deposition)

wet scrubbers

desulfurization and clean power plant exhaust

coal washing

crushes coal with liquid and allows impurities to settle out

flue-gas seperation

removes CO2 and makes into usable co2 (dry ice, soda)

OPEC

organization of petroleum exporting countries. saudi arabia and venezuela have 70% of oil

other names for oil

crude oil, petroleum, liquid containing hydrocarbons

Alaska Arctic National Wildlife refuge (AANWR)

Taiga and tundra biomes, 3 types of north american bears, porcupine and caribou. 4.3-11 billion barrels there=1 year of energy in US. big oil wants money, oil prices decrease, provide jobs, but native ppl on the land

Refining crude oil

heat and boil oil: gasoline boils out first, then diesel, then asphalt is last among other things

petrochemicals

any product that has a petroleum ingredient. medicine, plastics, petroleum jelly, synthetic fibers, etc

oil sands/tar sands

mix of clay,sand,water and bitumen. has to be processed before refined (costly) mostly found in Canada

oil shales

combustible mix of hydrocarbons that live in rock (kerogen). it is crushed, heated to release shale oil then heated to remove sulfur and nitrogen, then it is refined. found it wyoming, colorado, utah, can last 110 years

oil spills

Exon Valdez sea otters loose insulation ability, birds lose water repellency oil intake, fin erosion

Natural gas

russia and iran have abut half of it. versatile, clean burning. releases co2 and methane leaks

conventional natural gas

mostly methane, found above reservoirs of crude oil, can liquify and turn into lpg

unconventional natural gas

methane hydrate: coal + methane trapped under ice from anaerobic creatures

marcellus shale

pennsylvania, NY, Ohio. LOTS of natural gas

hydraulic fracturing/fracking

dig a hole, push lots of water into it, pressure breaks the rock and brings that natural gass up

benefits and drawbacks of fracking

+: less dependency on foreign oil, jobs, can make lots of money for companies

-: not regulated by clean air or water act, MASSIVE quantaites of fresh water, fracking fluid gets into water supply, kills wildlife.

solutions to fracking

increase regulation, increase monitoring, disclose chemicals in fracking fluid

nuclear

biomass: ethanol

fermenting plants, distils sugarcane, corn. found in brazil mostly,

benefits and drawbacks of biomass: ethanol

+: biodegradable, low co2, you can drive a car with it, no sulfur

-: deforestation, increased use of fertilizers and pesticides, crops for fuel and not food

biomass: electricity

burn biomass to heat h2o and turn a turbine. charcoal

benefits and drawbacks of biomass: electricity

+: carbon neutral

-: deforestation

photovoltaic cells/solar panels

sun hits silicon and electrons move one way producing electricity. found it germany, china, southwest

benefits and drawbakcs of solar panels

+: no co2 or sulfur while producing electricity, subsidies in germany, tax breaks in US, getting cheaper over time

-: costly to manufacture, toxic chemicals from mining silicon and manufacturing, useless at nightime

active solar

mirrors direct sunlight to central collector with salt and it can use or store the energy. found it california, arizona, desert places

benefits and drawbacks of active solar

+: no pollution, energy 24/7

-: costly, need a lot of water, space and mirrors, delicate habiate with no one near to use the energy

hyrdoelectic dams

water falls through a penstock and spins a turbine. found everywhere with rivers. creates reservoirs

benefits and drawbacks to hydroelectic dams

+: flood control, cheap to maintain, increase in tourism and recreation, irrigation, run of the river

-: release methane from plants under water, fish cant move (fish ladder), high initial costs

tidal

giant dams in the ocean that spin turbines as the tides go in and out. found in coastal areas

benefits and drawbacks to tidal

+: tide is predictable, no fuel, not greenhouse gasses

-: costly to build, displaces animals, ugly, damages habitat

geothermal

underground water heated by magma, steam turns a turbine. can also do under your house with air for heating and cooling. found at hotspots with thin crust

benefits and drawbacks to geothermal

+: cheap at a reservoir, no co2

-: scarce reservoirs, not good outside of them, specific locations

wind

pressures move air to make wind and turn a turbine. found in texas, kansas, costal areas

benefits and drawbacks to wind

+: cheap to maintain, no pollution or greenhouse gasses, jobs, can grow crops or graze cattle under them

-: noise pollution, costly to build, flying animals hit them, ugly

hydrogen fuel cells

at the anode, hydrogen is oxidized and elections flow to to the cathode. at the cathode, o2 reacts with hydrogen to make water. water and heat are byproducts. found in california

benefits and drawbacks to hydrogen fuel cells

+: no co2, decrease climate change and ocean acidification,

-: costly, h2 storage, distribution system