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Non-renewable Energy Resources

• https://www.youtube.com/watch?v=FbMo3ZsXZv4 fossil fuels

• https://www.youtube.com/watch?v=_8VqWKZIPrM How fossil fuels are formed

• https://www.youtube.com/watch?v=6qKadxyMOYY Fracking

• https://www.youtube.com/watch?v=Uti2niW2BRA Fracking

• https://www.youtube.com/watch?v=v6F0TuV3JMg Centralia Coal Fire

History of Energy Use• Early use of energy was muscle power –

human and then animal.

• With the coming of the Industrial Revolution, energy needs increased.

• Use of energy changed from muscle to burning biomass to fossil fuels.

• Changed from renewable to non-renewable sources. Most of commercial energy today is oil.

Laws of Energy

• First Law of Thermodynamics – during energy transformations, energy is neither created nor destroyed (Law of Conservation of Energy).

• Second Law of Thermodynamics – during energy transformations, the amount of useful energy is decreased; due to entropy, useful energy is converted to heat.

Net Energy

• It is the amount of high quality useful energy available from an energy resource.

• In order to determine this, the amount of energy lost from second law and energy used to extract the energy source must be subtracted.

Efficiency

• How much work can by gotten out of each unit of energy used.

• Examples:– Incandescent bulb: 5% efficiency – CFL: 20%– Internal Combustion Engine: 6%– Nuclear Power Plant: 15%– Coal Fired Power Plant: 35%– Photosynthesis: 1%

Coal

• Solid fossil fuel formed from dead land plants, which lived 300 to 400 million years ago, as a result of heat and pressure.

• Mostly made of C, but contains some S and trace amounts of Hg and radioactive substances.

Coal Extraction

• Coal is removed by both surface and subsurface mining.

• Leaves behind large scars on the land and large amounts of toxic wastes.

• Processing and burning of coal releases sulfur dioxide, mercury, and radioactive particles.

Coal Supplies

• Proven coal reserves:– 25% in US– 16% in Russia– 12% in China

• How long will reserves last?– Answer varies, but at least 200 + years.

Depends on consumption rate and grade of coal used.

Coal Formation

• Peat– Partially decayed plant matter (low heat)

• Lignite (brown coal)– Low heat and low S

• Bituminous (soft coal)– High heat and high S (large supplies)

• Anthracite (hard coal)– High heat and low S (supplies limited)

Peat

Lignite

Bituminous

Anthracite

Advantages of Coal Usage

• Large reserves left

• High energy yield

• Fairly inexpensive

• Infrastructure well developed

• Technology available to reduce air pollution

Disadvantages of Coal Usage

• Great impact on environment including land disturbance, air and water pollution

• Requires large amounts of land• Human health threats• Releases carbon dioxide when burned• Releases radioactive particles and mercury into air• Sulfur dioxide released contributes to acid

deposition

China and Coal

• 70% of the commercial energy in China is provided by the burning of coal.

• 33% of the world’s coal supply is used by China

• At current consumption rates, China will use up it’s supply of coal within 40 years.

• Pollution controls in China are very weak.

• Leads to high levels of SOx and NOx in the atmosphere resulting in acid rain and respiratory and cardiovascular issues in humans.

• China’s pollution is a for other countries as well: acid rain in Asian nations, high ozone levels in California, and even Hg in Oregon rivers.

• World’s leading emitter of CO2.

• High levels of particulate matter released which result in premature deaths.

Crude Oil• Thick liquid consisting of a large number of

combustible hydrocarbons as well as small amounts of S, N, and O.

• Often found in conjunction with natural gas.

• Formed as dead organisms on the seafloor were covered over with sediments faster than they decayed and over years, heat and pressure converted the material to oil.

Extraction of Oil

• Only 35 to 50% of oil can be extracted.

• Drilling for oil has minimal impact on land and does not require large spaces, but transporting oil often results in spills.

• Oil must be refined (distilled to separate components) before use.

• Petrochemicals are used as raw materials to make things such as pesticides, plastics, synthetic fibers, paints, medicines, etc.

Products of Oil Refining

Oil Supplies

• 1 barrel of oil = 42 gallons

• Largest reserves are in Middle East (OPEC controls most of world’s oil supply)

• OPEC (organization of petroleum exporting countries)

• 80% depletion within 40 to 90 years; U.S. in 10 to 50 years.

Reserves as of 2006

Pros of Crude Oil

• High net energy yield

• Easily transported

• Low land use

• Well developed technology

• Efficient distribution system

Cons of Crude Oil

• Supply is getting low.

• Low prices of the past have encouraged waste

• Air pollution is released when burned

• Carbon dioxide released when burned

• Water pollution when spilled

Arctic National Wildlife Refuge

• Found on Alaska’s north slope

• Fragile ecosystem and home to numerous species

• Oil companies want to drill here b/c they think it might contain oil and natural gas deposits

Pros and Cons of Drilling

• Increase US oil supplies and reduce imports

• Jobs

• Lower oil prices

• New drilling techniques reduce harm to environment

• Have safely drilled in Alaska before

• Small chance of finding more than a 7 to 24 month oil supply which won’t reduce imports

• Costs too high to save $$• Oil spill would do

significant harm and not worth risk

• Slant drilling may allow drilling to be done outside refuge

Natural Gas

• Usually found above oil deposits

• Consists of mostly methane as well as other, heavier hydrocarbons and small amounts of hydrogen sulfide.

• Formed by deposits on the sea floor

• When natural gas is tapped, it must be liquefied for transport

Natural Gas Reserves

• Estimated that the supplies will be available for about 125 years

• Most of the reserves are found in Russia (31%) followed by Iran

• 36% of the reserves are in the Middle East

Natural Gas Reserves

COWS??????

Advantages of Natural Gas

• Fair amount of supplies

• High net energy yield

• Low cost

• Less air pollution

• Moderate environmental impact

• Low land use

• Easily transported by pipeline

Disadvantages of Natural Gas

• Releases carbon dioxide when burned• Methane can leak from pipelines (worse

greenhouse gas than carbon dioxide)• Difficult to transport from one country to

another• Needs pipelines for transport• Highly explosive as LNG• Burned off and wasted b/c of low cost

Oil shales and tar sands

• Tar sands: Mixtures of clay, sand, water, and bitumen which is a thick and sticky heavy oil with high S content

• Oil shales: Fine grained sedimentary rock containing kerogen which can be distilled to produce shale oil which is thick and must be refined in part to remove S, N, and other impurities

Tar sands

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