NONRENEWABLE ENERGY Chapter 16. Energy Resources Energy is the ability to do work – Flows in a one-way path through the atmosphere, hydrosphere and biosphere.

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NONRENEWABLE ENERGY

Chapter 16

Energy Resources

• Energy is the ability to do work– Flows in a one-way path through the atmosphere,

hydrosphere and biosphere.– Examples:

Potential energy Kinetic energyMechanical energy Chemical energySolar (light) energy Electrical energyThermal energy (convection or conduction)

Units of Energy

• Energy unitsJoule (J)*Calorie (cal)British thermal unit (Btu)*Kilowatt hour (kW)*

Power UnitsWatt (W)*Horsepower (hp)

LAWS OF THERMODYNAMICS

• First Law of Thermodynamics – energy cannot be created or destroyed, only converted from one form to another.

• Second Law of Thermodynamics – all energy conversions decrease the usefulness or quality of energy (high quality to low quality).

• Because of the 2nd law, energy cannot be recycled.

History of Energy Use in the US• Human and animal power; wood

• Coal – used during the Industrial Revolution to power steam engines- coal overtook wood in 1885

• Oil – cleaner burning than coal; has more advantages in enginesOil overtook wood in 1915; overtook coal in 1950.

• Natural gas

• Hydropower – overtook wood around 1968.

• Nuclear – 1972 (wood); 1973 (hydro)

Energy Usage Models:World vs. US

Non-Renewable Energy Sources

• Fossil Fuels – coal, oil and natural gas.

• Estimated reserves – educated guesses about how much of a fossil fuel is left and where it may be found.

• Proven reserves – exact amounts of oil that can be economically obtained; determined only after drilling.

Oil (Petroleum)

• Most widely used resource in the world.

• Greatest use in US is for transportation.

• No new oil refineries have been built in US since 1974.

• Since 1985, oil extraction in the US has declined.

Extraction

• Crude oil – a thick liquid containing hydrocarbons that we extract from underground deposits and separate into products such as gasoline, heating oil and asphalt.

• Only 35 – 50% can be economically recovered.• As prices rise, about 10 -25% more can be

recovered from expensive secondary extraction techniques.

• This lowers the net energy yield.

Recovery Methods

1) Primary recovery – conventional pumping; removes about 25% of the oil.

2) Secondary recovery – involves injecting brine or steam into a well to pressurize and force out remaining oil; removes about 50% more.

3) Enhanced recovery – carbon dioxide injected into oil field; breaks up oil droplets and allows for more removal.

Refining Process

• Uses distillation process and melting points of various hydrocarbons.

• 4 Steps1) Distillation – separates different hydrocarbons by

melting points.2) Hydro-cleaning – removes sulfur and contaminants.3) Cracking – breaks larger hydrocarbons into smaller,

simpler ones.4) Blending – adding smaller hydrocarbons to make

different blends (motor oil).

Economics and National Security

• The US has become increasingly dependent upon foreign oil reserves.

• Problems and Concerns1) 30% of US’ balance-of-payment deficit goes to oil.2) The Middle East is politically unstable; US needs a

strong military presence to maintain access to oil.3) Domestic supplies are running low; no new oil

fields expected to be found.

Foreign Oil

• OPEC – Organization of Petroleum Exporting Countries

– Formed in 1960 so that developing countries could get higher price for oil.

– 11 OPEC countries (Algeria, Iran, Saudi Arabia, Kuwait, Nigeria, Indonesia, Libya, Qatar, United Arab Emirates and Venezuela)

– Have 78% of world’s proven oil reserves and most of world’s unproven oil reserves.

Peak Oil Production

• US oil production “peaked” in 1974………

• After global production peaks and begins a slow decline, oil prices will rise and could threaten the economies of countries that have not shifted to new energy alternatives.

Stats

• US is the largest oil user; has only 2.9% of the world’s proven oil reserves.

• US imports between 60% – 70% of its oil, followed by China and Japan.

• Most of US domestic oil comes from offshore drilling in the Gulf of Mexico, followed by Alaska’s North Slope.

• Domestic oil costs $7.50 - $10/barrel; costs $1-$2/barrel from Saudi Arabia.

Oil Consumption by Country

Oil Consumption Country 2004 Petroleum Consumption

(Thousands of Barrels per Day)

United States 20,731.2

Japan 5,353.2

United Kingdom 1,826.7

China 6,400

India 2,450

*At this rate, oil will last about 44 years.

Stats cont.

• Saudi Arabia could supply the world with oil for about 10 years.

• Alaska’s North Slope could meet the world oil demand for about 6 months (US – 3 years).

• Alaska’s Arctic National Wildlife Refuge would meet the world demand for 1-5 months (US: 7- 25 months).

Options

• What can we do?1) Look for more oil

2) Use or waste less oil

3) Develop alternatives

Other Sources of Oil

• Oil Shales and Oil (Tar) Sands– Heavy and tar-like oils– Could supplement conventional oil– But………environmental problems

1) High sulfur content2) Extracting and processing produces toxic sludge, uses and

contaminates large volumes of water3) Expensive4) Requires large inputs of natural gas which reduces net

energy yield

Ways to Extend Oil Supplies

• Increase the fuel efficiency of vehicles

• Utilize fossil fuels other than just oil

• Develop alternative fuels

• Take a hit in the ‘ole pocket book’

Taxes

Advantages

1) Currently available2) Simple combustion process that can directly heat or generate electricity3) Inexpensive4) Easily distributed, handled and stored5) Mainly used for transportation and in

technologies such as plastics, lubrication, etc.

Disadvantages

1) Dependence on foreign sources2) Pollution caused by spills and off-shore drilling3) Air pollution caused by burning4) Probably a contributor to global warming5) Questionable availability over a long period of time6) Major price swings based on politics7) Transported thousands of miles by tankers, pipeline, and trucks - all of which can add up to a lot of environmental damage.

NNATURAL GAS

Natural Gas

• Consists mostly of methane; but can also be in the form of butane, ethane and propane; removed as liquefied petroleum gas (LPG).

• Often found above reservoirs of crude oil and is sometimes burned off as an unwanted by-product of oil drilling. WASTEFUL!

• Also found in 1) Coal beds2) Ice crystals under the arctic permafrost3) Deep ocean sediments

Stats

• Russia and Iran have almost half of the world’s reserves of conventional natural gas, and global reserves should last 62 – 125 years.

• The US has a 25 year supply, with an estimated reserve of 50 years.

• Imports come mostly from Canada.

Groundwater contamination

Some damage to land due to drilling

The Future?

• Some analysts see natural gas as the best fuel to help us make the transition to improved energy efficiency and greater use of renewable energy.

• Honda offers a cng version of the Civic….

• Ford offers kits to convert gas engines to cng….

• cng = compressed natural gas

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