Chapter 2

Section 2.1

Renewable & Nonrenewable resources

1. Renewable Resources

• Any material or energy source that cycles or can be replaced within the period of a human lifespan

Examples:• Crops• Soil• Wind • Sunlight• Water• Biomass fuels• Geothermal energy

A. Crops (Food & Fiber)

• For human or livestock consumption

• Wild or planted

• Wild or domestic animals consume

B. Soil• Living and non living components

• Forms over thousands of years by erosion.

• Rate of formation is higher in hot, humid climates

• Renewable as long as the living matter remains fertile

• If soil abused it will not sustain life

C. Wind – air in motion• Tries to evenly heat Earth

• Highly variable

• Used to generate electricity

• http://vimeo.com/13759005

D. Sun (solar energy)

• ultimate energy source – needed by autotrophs

• Experts say at least another 5 billion years left

E. Water• Renewable through the hydrologic cycle

• 3% is freshwater

• 1% is usable freshwater

• Pollution is a concern

• Depleted faster than

can be recharged.

F. Biomass Fuels (organic matter)

• Organic matter that contain stored solar energy

• Mostly plants, Wood products, dried vegetation, crop residues

• Can be animal waste

• Very common fuel!

• 1st energy source used

by humans

• 90% of energy in poorest

countries

G. Geothermal energy

• Use the heat generated deep within the Earth

• Fueled by the decay of radioactive elements

• Heat transferred by water to the surface

• drive electric generators & heat homes

2. Nonrenewable Resources

• Material or energy that can NOT be replaced during human lifespan

1. Ores• Mineral deposits; metals and non

metals• Rocks – mixtures of one or more

mineralsQuarry – an excavation pit in the

Earth’s crust from which rock resources are removed

• Metallic ores- Fe, Cu, Al, Pb, Ag, Au, Mgno metal mines presently in

PA

• Nonmetallic ores (in PA) – sand, clay, granite, limestone, gravel, slate, sandstone

2. Fossil Fuels

• Fuels that release energy when burned

• Ex: charcoal, peat, coal, oil, & natural gas

• Take millions of years to form

• Solar energy stored

• Developed countries use coal, oil and natural gas

• Undeveloped countries use wood, charcoal, peat

A. Coal

• Fossil fuel formed from dead wetland plants that undergo chemical changes over millions of years

• PA produces more than half of its electricity from coal burning power plants

• Heat water → high pressure

steam → turbine → generates

electricity

1. Coal Formation

• 1st stage- peat 50% carbon

• 2nd stage- lignite

peat is compressed & O, H, H2O are forced out

70% carbon

• 3rd stage- bituminous

“soft coal”

pressures and temps cause change

85% carbon

western PA

most used for producing electricity

• 4th stage- anthracite

“hard coal”90% carbon

cleanest burning coal

Eastern PA

minor role in fueling power plants

2. Leading producers of coal:Former soviet union: ~50%

China: ~20%

US: ~ 15%

Wyoming, W Virginia,

Kentucky, PA

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3. Coal mining methods

• Three Methods– Room and Pillar Method– Longwall Method– Surface method

a) Room and Pillar MethodMost popular

Rooms are cut into the coal bed

Leaves a series of pillars (columns of coal) that support the mine room and control the flow of air

Rooms are 20-30 feet wide and the pillars are up to 100 feet wide

Remove as much coal as possible

remove coal from remaining pillars roof falls in…abandon the mine

2626

b) Longwall Methodover 1/3 of the underground coal production in PA and surrounding states

A cutting head moves back and forth across a coal seam, causing pieces of coal to fall onto a flexible conveyor for removal from the mine

Special roof supports are moved as the seam is cut

The roof in mined-out areas falls as the supports are advanced

http://science.discovery.com/videos/how-do-they-do-it-coal-mining.htmlhttp://science.discovery.com/videos/how-do-they-do-it-coal-mining.html

c) Surface Mining• Coal is located close to surface

• Explosives used to loosen coal

• Three types:– Area Surface Mines

used in flat terrain and is series of steps

– Contour Surface minesFollows topography

– Open Pit Surface Mines

Coal seams are thick

4. Coal and the Environment

a)Bituminous coal contains pyrite (fool’s gold); when exposed to air and water forms sulfuric acid and iron hydroxide (yellow boy)

FeS + O2 + H2O → H2SO4 + FeOH

acid mine drainage in streams lowers pH

b) Burning coal

emissions can cause acid rain

c) Mine subsidence

d) Reclamation for surface mining– restoration of the land with vegetation and land’s original topography

Required by PA by Act passed in 1977

B. Petroleum/natural gas

• Formation – remains of plants, bacteria, algae and microscopic marine organisms (protists)

• PA produces small amount of oil but Titusville, PA in 1859 had 1st oil well. Produced half of the world’s oil until 1901 when Texas oil boom began

• Source rocks – where oil and gas form

• Found in reservoirs (migrate there since they are fluids)

• Oil is denser than gas, so it is found near the bottom

• Gas is found near the surface of the reservoir

• Rig – complex set of machines, engines, pumps pipes and drills used to drill for oil and gas

http://videos.howstuffworks.com/medialink/14668-ultra-deep-water-oil-drilling-video.htm

http://videos.howstuffworks.com/science/oil-drilling-videos-playlist.htm?page=2#video-3664

Global Energy Use• Using fossil fuels increases air

pollution & produce more greenhouse gases

• Overall effect = increase global warming!

• Conservation – careful use of a resource so that its supply will last longer

• Sustainability- not depleting natural resources or being harmful to an area.

Complete “You Solve it” on page 51

3. Alternate Energy Sources

• To decrease our dependence on fossil fuels

• Sun, wind, geothermal energy, hydropower, nuclear energy, trash

a) Solar Energy

• Can heat buildings, water, provide electricity

• Solar cells (photovoltaic PV)- convert solar rays to use

• Conditions: amount, intensity, direction and angle of light

Types:

• Passive- uses sun to heat water columns, bricks, or tiles that are part of a building and releases heat when the surrounding temp decreases at night; does not use mechanical devices

• Active –3 components: a solar collector, a solar storage system, and a heat transfer system; generates more heat than passive

• Thermal systems – concentrate sunlight to produce heat → water to boil → steam →rotate turbine → produces electricity

Disadvantages:

• Cost

• Light duration and intensity

• Electricity storage

b) Wind• Wind turbines create electricity• Conditions: blade length 90 – 130 ft; wind

speed• More than 24 wind turbines in PA on 5

windfarms;• Supply about 3000 homes• Farms, schools, business also use• Fastest growing alternative energy method• Wind is free!

Disadvantages: Unreliable: Wind intensity and duration Noise – sm jet engine Requries multiple turbines to make impact

c) Hydropower• Dams store water that flows through

turbines to create electricity

• 10% of energy in USA

• 0.5% in PA (23 dams)

• Conditions: increase water movement

• No pollution; no waste products

• Cost less to operate than fossil fuel plants

Disadvantages: Water resource necessary Disrupts natural flow of water, sediments

and fish migration Scour holes (below dam)

d) Geothermal energy• Water from deep reservoirs are brought to

the surface as steam and used to create energy

• Conditions: get hot water to surface

• 2 dozen countries use, including the US

• Capital of Iceland receives all its heat from geothermal

Disadvantages: High cost Locations-suited to certain regions Can run out of steam

e) Nuclear power• Alternative source but definitely NOT

RENEWABLE

• Generated inside a facility called a reactor

• Controlled nuclear fission reaction - uranium or plutonium struck by a neutron

• Heat energy from chain reaction and works same as other power plants with steam

• 25 countries currently use

• France 75% of energy is nuclear

• USA 15 - 20% electricity

• PA has 5 locations with 9 reactors: Beaver Valley, Three Mile Island, Peach Bottom; Susquehanna, Limerick

• 1/3 of our electric from nuclear power

http://www.nrc.gov/info-finder/reactor/bv2.html

• Conditions: radioactive materials, safety, waste, sell people on the method

• Use less fuel than coal to produce equal amount of electricity

• US is not dependent on other countries for uranium sources

• Less air pollution

Disadvantages: Accidents at sites 1979 accident at Three Mile Island

considered most serious nuclear accident in US history; partial reactor meltdown; no other reactors commissioned since then

Waste products

f) Trash• Burned to generate power

• Decaying food scraps- methane gas- trap the gas to be used to create electricity

• In PA we have 7 sites

Disadvantages: Toxic waste mixed in with waste Has to be sorted

g) Hydrogen• H in the H2O

• Basically a battery that uses H

• Does not need replaced like a battery and uses continuous source of H

• Hydrogen is thought to be fuel of the future- clean source with no emissions

• Hydrogen fuel cell works like a battery

Disadvantages: Takes electricity to separate H from water

and this takes fossil fuel energy

Read pages 59 – 61 and pages 64-65

Answer questions 1- 7

Also answer the following question:

8. Explain where you can find the plastic code numbers for recycling and what the numbers indicate concerning recycling.

All answers may be placed in your notebooks

Come dressed with appropriate shoes for going outside tomorrow….we may visit the pond and trail.

Test moved to Friday !