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Chapter 12. Energy From Fossil Fuels. Warm-Up. Read the introduction to chapter 12 and be able to answer the following questions What is ANWR and what is its significance? What are the pros and cons of exploiting the natural resources found in ANWR? . 12.1. - PowerPoint PPT Presentation
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Chapter 12
Energy From Fossil Fuels
Warm-Up
• Read the introduction to chapter 12 and be able to answer the following questions– What is ANWR and what is its significance? – What are the pros and cons of exploiting the
natural resources found in ANWR?
HARNESSING ENERGY SOURCES: AN OVERVIEW
12.1
Industrial Revolution• Throughout history, the major source of energy was
human labor– Limiting factor to machine technology in early 1700s was
finding a power source• Late 1700s
– Development of the steam engine– Need energy source to create the steam that drives the turbine– At first was firewood, then coal was substituted
• End of 1800s– Coal had become the dominant fuel and in 1920 provided 80%
of all energy used in the U.S.
Steam PowerSteam-driven tractors marked the beginning of the industrialization of agriculture. Today tractors half the size do 10 times the work and are much easier and safer to operate
Oil Rules
• Late 1800s three technologies provided an alternative steam engines– Internal combustion engine, oil-well drilling,
refinement of crude oil into gasoline• More convenient• Better air quality more horsepower• By 1951 crude oil became the dominant energy source
for the nation– Little is known about the reserves of oil supply
Natural Gas
• 3rd primary fossil fuel• Found in association with oil • Methane – Produces only CO2 and H2O as it combusts
• Burns cleaner than oil or coal in terms of pollution
• Inconvenient to transport– Most natural gas found in oil fields was (and still is) flared
which is a waste– Eventually U.S. constructed pipelines connecting wells
with consumers
Coal, Oil, Natural Gas
• Provide 85% of U.S. energy consumption and 87% of world energy consumption– Remaining power is furnished by nuclear energy,
hydropower, and renewable sources• Crude oil provides 35% of total U.S. energy demand• Coal provides 22% of total U.S. energy demand
Energy consumption in the U.S.Note how the mix of primary sources has changed over the years and how the total amount of energy consumed has continued to grow. Note also the skyrocketing increasing the use of oil after WWII (1945) as private cars became more common
Global Primary Energy Supply
Electrical Power Production
• Electrical Energy– The amount of work done by an electric current
over a given time– Electricity is an Energy Carrier• Transfers energy from a primary source to its point of
use• Therefore electricity is a secondary energy source
– More than 33% of fossil fuel production is now used to generate electricity in the U.S.
Generators
• Invented in the 19th century– Michael Faraday discovered that passing a coil of
wire through a magnetic field causes a flow of electron (electrical current) in the wire
• Electric Generator– Coil of wire that rotates in a magnetic field or that
remains stationary while a magnetic field is rotated around it• Converts mechanical energy into electric energy
Principle of an electric generatorRotating a coil of wire in a magnetic field induces a flow of electricity in the wire
Turbogenerators
• Most widely used technology to create electricity is using the pressure gradient of steam and water to turn a turbine– Turbine = paddled wheel that is coupled with the
generator• Other types of turbogenerators in addition to
steam powered include gas and hydro driven turbines
Where Does Electricity Come From?
• Most utility companies are liked together in pools
• Electric companies need to balance electricity supply and demand, regardless of daily or seasonal fluctuations
• Primary source for generating electricity in the U.S. is coal
Disadvantages of Electric Generation Plants
• Coal burning power plants– Major source of acid rain (high sulfur content in
coal)• Hydroelectric plants– Flooding terrestrial habitats from dams
• Nuclear power plants– Disposal of nuclear wastes
Demand Cycles
• As demand for energy rises during the day, the electric companies draw on additional plants that can be turned on and off
• Deficiency in available power is called a brown out
• Total loss of power is called a black out– August 14, 2003 was the largest black out in U.S.
history• Cost $30 billion to economies of U.S and parts of Canada
Demand Cycles
• Summer is the season that draws the most electricity
• Mon – Fri uses more energy, as opposed to the weekends
• Peak time for energy use is 6:00 AM – 6:00 PM
Weekly Electric DemandElectrical demand fluctuates daily, weekly, and seasonally. A variety of generators must be employed to meet base, intermediate, and peak electricity needs
Efficiency
• Production of electricity has an efficiency of only 30%
• 60-70% of the primary energy is lost in the form of heat– 2nd law of thermodynamics– Conversion losses
• Consequence of the need to maintain a high heat differential between the incoming steam and the receiving turbine so as to maximize efficiency
• Heat energy will go only toward a cooler place, so it cannot be recycled into the turbine
Cooling TowersNecessary to cool and re-condense steam from the turbines before returning it to the boiler. Air is drawn in at the bottom of the tower, over the condensing apparatus, and out the top by natural convection. Cooling is aided by the evaporation of water that condenses in a plume of vapor as the moist air exits the top of the tower
Cooling Water
• Alternative to cooling towers is to pass the water from a river, lake, or ocean over the condensing system– Waste heat energy is transferred to this water and
returns to source warmer– Thermal Pollution
Energy Flow
• Primary energy use is divided into four categories– 1. Transportation – 27%• Depends entirely on petroleum
– 2. Industrial processes – 33%– 3. Commercial and residential use – 41%– 4. Generation of electrical energy – 41% • which goes into categories 2, and 3 as a secondary
energy use
EXPLOITING CRUDE OIL12.2
Crude Oil
• U.S. Depends on foreign oil for more than 65% of our crude oil
• Foreign sources are costly– Trade imbalances, military actions, economic
disruptions, coastal oil spills
How Fossil Fuels are Formed
• Derived from the remains of living organisms• Fossil fuels are accumulations of organic
matter from rapid photosynthetic activity that occurred at various times in Earth’s history
Renewal
• Additional fossil fuels may still be forming through natural processes today
• They cannot be considered renewable because we use fossil fuels far faster than they ever formed– It takes 1,000 years to accumulate the amount of
organic matter that the world now consumes each day
Crude Oil Reserves
• Amounts of crude oil that are estimated to exist in the Earth are called estimated reserves
• Oil fields that have been located and measured are called proven reserves
• The withdrawal of oil or gas from the field is called production
Oil Recovery
• Primary recovery (conventional pumping) can only remove 25% of oil in an oil field
• Further removal (secondary recovery) of up to 50% of the oil field is often possible, but it is more costly because it involves changing pressure in the oil reservoir by injecting brine or steam
• As more effort is put into extracting the oil, the price per barrel will increase
Declining U.S. Reserves and Increasing Importation
• Late geologist M. King Hubbert proposed oil exploitation in a region would follow a bell – shaped curve– U.S. production would peak between 1955 -1970– U.S. now has become increasingly dependent on
foreign oil
Oil Crisis of 1970s
• Low price of oil from Middle Eastern countries caused U.S. And other HDC to become dependent on foreign oil
• A group of predominantly Arab countries known as the Organization of Petroleum Exporting Countries (OPEC) formed a cartel and agreed to restrain production in order to get higher prices
Oil Crisis of 1970s
• OPEC initiated an embargo of oil sales to countries that gave military and economic support to Israel– Caused oil crisis in U.S.– Since then, OPEC was able to keep supplies tight
enough to force prices higher and higher (supply and demand)
Recovery from 1970 Crisis
• Significant discoveries in Mexico, Africa, and the North Sea made the world less dependent on OPEC oil– As a result (and the fact OPEC can’t control its own
oil production) there was an oil “glut”• Supply exceeded demand and caused cost of oil to
decrease until late 1999
Results of High Oil Prices
• Increase the rate of exploratory drilling for new oil sources
• Increased renewed production from old oil fields
• Increased efforts toward fuel conservation• Decreased consumption• Increased development of alternate energy• Decreased dependency on foreign oil
Results of the Oil Crisis• Exploratory drilling increased• Alaska pipeline was constructed because of the discovery of oil
in Prudhoe Bay• Research to increase fuel efficiency increased• Conservation goals for buildings to increase insulation and
efficiency of appliances• Development of alternative energy sources began• Strategic oil reserves were created
• These steps are only economically appealing when the price of oil is high!
Domestic Oil
• Continued to drop as proven reserves were drawn down
• Alaska reached its peak in 1988• Consumption rose because of increase in
highways and miles/year cars are driven• U.S. dependence on foreign oil in 2004 has grown
to 66%• Single largest factor in the U.S. balance-of-trade
deficit is purchase of foreign oil.
Inflation corrected cost of total oil imported to the U.S. economy
Cost in dollars per barrel and net imports
Gasoline prices in today’s dollars
Problems of Growing U.S. Dependency on Foreign Oil
• 3 problems resulting from the U.S. dependency on foreign oil– Cost of purchase– Supply disruption due to political instability in the
Middle East– Resource limitations
Cost of Purchase
• The cost for foreign crude oil represents about 30% of our current balance-of-payment deficit– $805 Billion in 2005
• Price we pay at the pump is basically the same whether the oil is produced domestically or abroad– Domestic oil – money circulates within our own
economy– Foreign oil – money leaves U.S. for another country
Persian Gulf Oil
• Fall of 1990 Saddam Hussein of Iraq invaded Kuwait– Which then produced 6 million barrels of oil a day
• U.S.-led Persian Gulf War of early 1991 threw Hussein’s armies out of Kuwait and gave the U.S. an ongoing presence in the Persian Gulf region
Subsidy
• Military costs associated with Persian Gulf oil is subsidized
• Market price of oil remains low where the actual cost is about $170/barrel
Other Sources
• U.S. has recently turned to more non-Middle Eastern oil suppliers– Canada replaced Saudi Arabia as the number-one
exporter of oil the U.S.• Venezuela, Columbia, and Mexico are also major
sources• However, these countries are on the down-slope of the
Hubbert curve, where production is declining
Resource Limitations
• Last major find in North American oil was the Alaskan oil field in 1968
• Once the peak in oil production has occurred– Oil production will begin to taper off in spite of world
demands– World will enter a new era of rising oil prices
• 21st century will become known as an era of declining oil use
• OPEC nations will once again dominate world oil market due to the fact the possess 62% of the world’s proven reserves
Ways to reduce Dependency on Foreign Oil
• 1. Increase fuel efficiency of our transportation system– Uses the most oil
• 2. Use other fossil fuel resources we have to make fuel for vehicles
• 3. Develop alternatives to fossil fuels
OTHER FOSSIL FUELS12.3
U.S. Reserves
• Unlike crude oil the U.S. has considerable reserves of – Natural gas– Coal– Oil shales / tar sands
Natural Gas
• In U.S. natural gas has been rising as a fossil fuel choice– Most fuel goes to industrial and residential uses,
natural gas is increasingly being employed to generate electrical power
– Gas-run cars are being developed• Cleanest burning fossil fuel– Produces carbon dioxide and water, but hardly any
hydrocarbons or sulfur oxides
Synthetic Oil
• Fischer-Tropsch process– Gas can be converted to a hydrocarbon that is
liquid at room temperature• Basically a synthetic oil
– Not as efficient, more costly
Costs of Natural Gas
• 3,600 mile gas pipeline is needed to conduct the gas to the lower 48 states from Canada and Alaska
• Gas drilling in the lower 48 states cause environmental damage from roads, wells, and pipelines
Coal
• 50% of our electricity comes from coal• In cost/BTU, coal is less expensive than natural
gas or oil• Large reserves domestically• Obtained by surface mining or underground
mining
Strip Mining
• More common than underground mining• Turn aside the rock and soil above coal seam
and remove the coal• Destroys ecology of region• Erosion and acid mine drainage has negative
effects on waterways
Coal Power
• Combustion releases per – 20,000 tons CO2
– 800 tons of SO2
• Most of which is removed if the power plant uses a scrubber
– 300 tons of fly ash/day– 800 tons of boiler residue ash/day• Both of which require special landfill
Synfuels
• Coal may be chemically converted to a liquid fuel called a synfuel
Oil Shales
• Extensive deposits in Colorado, Utah, Wyoming
• Fine sedimentary rock containing a m mixture of solid, wax-like hydrocarbons called kerogen
• When shale is heated, kerogen releases a hydrocarbon similar to crude oil
Disadvantages of Oil Shale
• 1 ton yields little more than half of a barrel of oil
• Mining, transportation, and disposal has negative impact
Oil Sands
• Sedimentary material containing bitumen– Extremely viscous, tarlike hydrocarbon
• When oil sands are melted, bitumen can “melt out” and be refined similar to crude oil
• Northern Alberta has largest oil-sand deposit– Causes damage to forests and wetlands to mine
ENERGY SECURITY AND POLICY12.4
Security Threats
• Oil Dependence– U.S. imported $300 billion worth of oil in 2006
• Terrorism– Nuclear power plants, hydropower, oil and gas
pipelines, refineries, tankers and the electrical grid are attractive targets for terrorist
Energy Policies
• The Cheney Report (CR) estimated that, over the next 20 years, oil consumption will increase 30%, natural gas consumption by 50%, and electricity demand will rise 45%
• Energy Policy Act (PA) acted on most recommendations of the CR but not always favorably
Supply Side Policies
• Exploring and developing domestic sources of oil– CR – open ANWR/offshore locations to oil
exploration– PA – promotes taking and inventory of offshore
rigs but not drilling in ANWR
Supply – Side Policies
• Increasing use of the vast coal reserves for energy– CR: add 1,300 – 1,900 new coal-fired power plants
in the next 20 years– PA: promotes energy from coal via clean coal
technologies, loan guarantees, and research incentives
Supply-Side Policies
• Continuing subsidies to oil and nuclear industries– CR: Provide tax incentives to encourage energy
production from fossil and nuclear fuels– PA: Guarantees $6.9 billion in tax incentives and
more in loans for nuclear and fossil fuel industries
Supply-Side Policies
• Removing environmental and legal obstacles to energy development– CR: Streamline permit process for drilling and
hydropower licensing and employ eminent domain to establish new electrical transmission lines
– PA: Provides tax credits for hydropower plants and streamlines permitting for drilling
Supply-Side Policies
• Providing access to remote sources of natural gas– CR: Expedite the planning and construction of a
natural-gas pipeline to bring Alaskan natural gas to the lower 48 states
– PA: requires periodic reporting of progress in the pipeline construction, which now depends on state and private monies.
Demand-side policies
• Increasing mileage standards for motor vehicles– CR: student a provide recommendations to
increase the CAFE standards for motor vehicles, but in ways that wont negatively impact U.S. automotive industry
– PA: opposed raising CAFE standards, but continue to research topic. Granted consumer tax credits for fuel-efficient hybrids and other technologies
Demand-side Policy
• Increasing the energy efficiency of appliances and buildings– CR: promote higher efficiency standards for
appliances when possible, and cover additional appliances
– PA: provide tax breaks for manufacturers of energy efficient appliances, encourages energy star program
Demand-side policy
• Encouraging industries to use combined heat and power technologies– CR: provide tax credits for CHP projects– PA: requires utilities to buy power from CHP plants
and coal gasification for producing natural gas
Demand-side policies
• Promoting greater use of non-fossil-fuel sources of energy (nuclear and renewables)– CR: build more nuclear power plants, and increase
and subsidize alternative energy sources– PA: power sources covered in chapters 13 and 14
(under Energy Policy Act)
Review Questions
• 1-14