Chapter 12

1. Chapter 12 Energy From Fossil Fuels

2. 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?

5. 12.1 Harnessing energy sources: an overview

6. 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.

7. Steam Power Steam-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

8. 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

9. 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

10. 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

11. 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

12. Global Primary Energy Supply

13. 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.

14. 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

15. Principle of an electric generator Rotating a coil of wire in a magnetic field induces a flow of electricity in the wire

16. 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

21. 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

22. 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

23. 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

24. 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

25. Weekly Electric Demand Electrical demand fluctuates daily, weekly, and seasonally. A variety of generators must be employed to meet base, intermediate, and peak electricity needs

26. 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

27. Cooling Towers Necessary 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

28. 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

29. 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

31. 12.2 Exploiting crude oil

32. 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

33. 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

38. 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

39. 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

40. 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

41. 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

43. 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

44. 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)

45. 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

46. 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

47. 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!

48. 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.

49. Inflation corrected cost of total oil imported to the U.S. economy

50. Cost in dollars per barrel and net imports