Unit 6 APES

how efficient is electricity generation from coal

30%

examples of non-renewable sources

natural gas, oil, coal, nuclear

examples of potentially renewable

wood, biofeul

examples of non-depletable sources

wind, solar, hydroelectric, geothermal

what is cogeneration

using what energy we would waste as a different energy source

(conserving energy)

what are the 4 types of coal

lignite, sub-bituminous, bituminus, anthracite

what is the order of the energy contents

peat→lignite→(sub)bituminous→anthracite

what is the most common form of mining on the east coast

surface mining

(mountain top removal)

what does surface mining do for the environment

destroys it (overburden is put at the bottom of the mountain)

changes the geography of how water moves, habitat destruction, no vegetation, sediment in the water

how is surface mining economically advantageous

it cheaper, more accessible, safer, and overall easier

what is coal washing

trying to get all the soil off the coal

companies pay per until of weight so they don’t want to be paying for the weight of the soil

when does coal washing occur

prior to the burning of the coal

(also before transportation)

what is coal ash

the 20% of coal that doesn’t burn

how is coal ash managed

managed by putting it into a pond, you have to water down the ash

what is acid mine drainage

the groundwater and runoff water reacts with coal creating sulfuric acid

this water drains into surface waters and leeches heavy metals from the substrate

what is the surface mining control and reclamation act

government law that the grounds have to be reclaimed and put back to how it was before mining (original state)

what is petroleum (crude oil)

mixture of hydrocarbons, water, and sulfur

which fossil fuel do we use most

petroleum

what is a byproduct of crude oil

gasoline

where is petroleum found

from marine deposits

(current and former coastal areas)

which 3 countries have the highest reserves of petroleum

venezuela, Saudi Arabia, canada

Case Study: Arctic national wildlife refuge

exploratory drilling exposed the area had a ton of oil

trump opens refuge fro drilling bc he says US need their own supply and can’t rely on other countries

bad idea bc coastal plain is home of migrating birds, porcupines, caribou

Case Study: Tar Sands

predicted to run out of oil so Alberta Canada uses tar sands

what are tar sands

oil that holds on to sandy particles

if you heat the tar sand, the oil will separate from the sand

first process of capturing oil from tar sands

excavate the top of the surface - oil is right there

bring tar sand to a facility where they crush it, use water to separate the oil from the sand, then oil is collected

conventional process

vertically drill to a selected depth

crude oil is removed through pumping of natural pressure

oil is refined fro selected characteristics (plastics)

second way of capturing tar sands

take hot water, inject it into the top pipe, steam from hot water allows oil to heat up and detach from the sand, oil is collected

what is wrong with this

disrupts habitats - permafrost holds carbon so when you heat it, it generates methane

water contamination - if you melt permafrost you have excess surface water,

Tar sands related issue: Keystone XL Pipeline

Oglala aquaphor is the largest aquaphor in the US and provides US with drinking water

if the pipeline was built it could break Which could contaminate the water because lots of sandy soils are around it

what is an advantage of petroleum

refined to create lots of products

what is natural gas created from

the remains of ocean-dwelling phytoplankton

advantages of natural gas

almost no particulate matter, less CO₂ (cleaner burning)

conventional type of natural gas

comes from the ground

unconventional type of natural gas

comes from fracking

a.k.a shale gas

biogas type of natural gas

comes from landfills/manure (captures methane from anaerobic decomposition)

methane hydrates type of natural gas

methane in permafrost

where does fracking take palce

texas and oklahoma

how deep does fracking occur

very deep

5000-6000 ft

steps of fracking

-drill vertical well

-get to shale formation, turn drill bit to drag horizontally

-case the well (pipe that goes in the ground and protects ground water)

-well head head protection area (double case the well)

how does the gas get into the pipes

holes are broken in the piping

insert frack fluid

frack fluid is distributed at high velocity so fractures occur in the rocks (water fractures rock, sand holds cracks open)

two water related environmental issues of fracking

-ground water contamination (due to lack of casing, frack fluid escapes into water, some fracking fluid comes back up so they put in holding ponds which are contaminated with plastic) (plastic liners don’t effectively work)

-lots of water use

other environmental issues of fracking

earthquakes - pressure has to get released due to so many fractures in the rock

how does nuclear energy occur

uses fission to split uranium atoms for energy

where are uranium reserves

middle of US - texas

why do we enrich uranium

to make it more reactive (we make it lighter by removing neutrons to make it less stable)

energy generation steps

neutron is fired at enriched uranium atoms which causes it to split

heat is released as a result of fission

heat is used to boil water

steam spins turbine

powers the generator

advantage of nuclear energy

no air pollution, no CO₂ emissions

disadvanatges of nuclear energy

expensive, finding location is challenging, radioactive water disposal

Case Study: Yucca Mountains

giant repository waste hole in the ground bc they had to get rid of the nuclear waste

sources of solid biomass

wood, charcoal, animal manure

is biomass better for developing or developed countries

developing because it is cheaper

5 major air pollutants from burning solid biomass

particulates, carbon monoxide, nitrogen oxides, carbon dioxide, VOCs

2 different types of liquid biofeul

ethanol and biodiesel

what is ethanol

alcohol made from converting starches and sugars from plant material to alcohol and CO₂

what is biodiesel

a diesel substitute produced by extracting and chemically altering oil from plants

what are the 2 major countries that develop ethanol

US - corn

Brazil - sugar cane

benefit of liquid biomass

less CO₂ emissions, renewable natural available source

drawback of liquid biomass

a vehicle needs more liquid biomass to go the same distance it could go on gasoline alone

Passive solar heating

sun roof, greenhouse, not mechanical, uses sun

disadvantage of passive solar heating

usefulness is limited by availability of sun

which direction should you face PV cells

towards south to capture most energy (most constant sunlight)

Concentrated solar thermal systems

bunch of mirrors pointing to water so it boils and spin a turning to create energy

advantage of PV cells

(solar panels) no emissions, stays efficient for a while

disadvantage of PV cells

weather dependent, metals can leech into environment

advantage of concentrated solar thermal systems

high efficiency, clean

disadvantage of concentrated solar thermal systems

takes up a lot of space and can interfere with flight communication

benefit of geothermal

renewable with the source of heat never running out

hydrogen feul cell equation

H₂+O₂ →water and electricity

anthracite is what

the cleanest and has the most energy

lignite is what

lowest amount of energy

what does half-life control

rate of reaction

what are hydrogen fuel cells an alternative for

fuel for cars