Chapter 12 Nonrenewable Energy Resources

1. Chapter 12 Nonrenewable Energy Resources

2. All Energy Use Has Consequences • Oil spill off the coast of Santa Barbara in 1969 • 11.4 million liters (3 million gallons) • March 1989 Exxon Valdez spilled 53 million gallons crashed into a reef in Prince William Sound, Alaska. • April 2010 BP Deepwater Horizon oil well suffered a blowout releasing 206 million gallons.

3. In 2005 15 workers died in an explosion in a BP refinery in Texas. • Combustion process emits pollutants. • April 2010 an explosion in WV killed 29 coal miners. • Natural gas (“clean” fossil fuel) has lower particulate emissions. • Finding natural gas is detrimental to the environment (Thumper Trucks). • Use of water contaminates water. • Building pipelines is disruptive to the environment.

5. Nonrenewable Energy Accounts for Most of Our Energy Use Non-renewable: once used up cannot be replenished. Fossil Fuels: derived from biological material that became fossilized millions of years ago. Nuclear Fuels: are derived from radioactive materials that give off energy.

6. Worldwide Patterns of Energy Use • Determined by resource availability and affordability. • Basic unit of energy is the joule (J). • A gigajoule(GJ) is 1 billion joules (1x109)about 8 gallons of gasoline. • An exajoule (EJ)is 1 billion(1x109) gigajoules. • Quadrillion=s 1x1015 BTU

7. Oil, coal, and natural gas are the three largest energy sources. • Commercial Energy Sources: those bought and sold (coal, oil, and natural gas). • Subsistence Energy Sources: those gathered by individuals for their own immediate needs (developing countries).

10. The United States • The US produces about 70% of its energy needs. • 30% comes from other countries, primarily petroleum imports. • Industry uses the most followed by transportation.

13. Energy Types and Quality • Gasoline has good energy-mass ration, can provide energy relatively fast. • Produces large amount of air pollution per joule of energy released.

14. Energy Return on Investment (EROEI) • EROEI = Energy Obtained from the Fuel • ------------------------------------------ • Energy invested to obtain the fuel • The larger the EROEI the more efficient (and more desirable : )

16. Finding the Right Energy Source • Consider efficiency! • Electric Hot Water Heater • 99% efficient • Does not take into account the coal used to supply the electricity • Only 35% efficiency of fossil fuel to electricity

17. Gas Hot Water Heater • 80% efficiency. • Does not take into account delivering the natural gas. • Even though an electric water has a higher direct efficiency than the natural gas the overall efficiency of the electric water heating system is lower..but not much less. • Need to look at the overall system!!

18. Efficiency and Transportation • 30% of our energy usage in the US is used for transportation. • Uses gas, diesel and electricity. • Contributes to greenhouse gas emissions. • Public ground transportation more efficient than air.

19. Personal preference has an effect. • SUVs, minivans, and pick up trucks account for ½ of the vehicle sales in the US. • Hybrid electric vehicles account for only 2-3% of total sales.

21. Electricity is Convenient! • Primary Sources of Energy: Coal, oil, and natural gas. • Secondary Sources: Electricity (obtain it from a conversion of the primary source). • Electricity is an energy carrier: can be moved and delivered in a usable form! • 40% of energy used in the US generates electricity. • Of that 40% only 13% is available for end users.

23. Electricity Generation • Comes from primary sources: coal, natural gas, wind, or solar. • “Clean” at the point of use (no pollutants are emitted). • Pollution released at the point of production. • Only 35% efficient (from fuel to electricity). • Looking at the overall system, more efficient to burn wood or oil. • The energy source that entails the fewest conversions from its original form to the end is the most efficient.

24. Efficiency of Electricity Generation • Typical coal burning power plant has an efficiency of 35%. • Combined Cycle: natural gas-fired power plant has two turbines and generations is more efficient. • Natural gas is combusted and the combustion turns a gas turbine. • Waste heat boils water which turns a turbine. • May achieve efficiencies up to 60%.

25. Power plants have capacities- the maximum amount of electrical output. • 500 megawatts per hour =s 12,000 MWh (500mw x 24 hours). • Home electricity use is measured in kilowatt hours(kWh). • 1 megawatt =s 1000 kWh • Most power plants do not operate every day of the year. • Capacity Factor: the fraction of time a plant is operating (.9).

27. Cogeneration(combined heat and power): use of a fuel to generate electricity and produce heat. • Over 17,000 power plants in the US. • In 2009 they generated 3.9 billion MWh. • Coal is the backbone at 45%. • Natural gas is 2ndat 23%.

28. Fossil Fuels Provide Most of the World’s Energy • Coal, oil, and natural gas. • Come from organic matter that was formed 50-350 million years ago. • Decomposers typically break down dead biomass. • In places such as swamps, river deltas, and the ocean floor, a large amount of detritus material builds up in an anaerobic environment.

29. Decomposers cannot break this down. • Heat and pressure turns it into high energy solids, liquids and gases.

30. Coal • Largest coal reserves are found in the US, Russia, China, and India • Peat: precursor to coal. Made up of partly decomposed organic material, including mosses. • Four Types of of Coal: • Lignite • Subbituminous • Bituminous • Anthracite

32. Advantages: • Energy dense. • Plentiful. • Easy to exploit with surface mining. • Low cost to extract, not much technology needed. • Once extracted, easy to handle, needs little refining. • Easy to transport.

33. Disadvantages • Released far more carbon dioxide into the atmosphere compared to natural gas or oil. • Contains impurities, sulfur, which is released into the atmosphere when burned. • Trace metals such as mercury, lead, and arsenic are also released. • When burned these are released into the air or left behind in the ash. • 1,450 coal mines in the US. • 3-20% of what is burned is left as ash. • Ash deposits must be maintained.

35. Petroleum • Hydrocarbons, water, and sulfur liquid found in underground deposits. • Being fluid is great! • Remains of ocean-dwelling organisms phytoplankton that died 50m-150mya. • Found in porous less dense sedimentary rocks. • Once formed must be extracted and transported by a pipeline. • Petroleum also contains natural gas. • Crude Oil: liquid petroleum that is removed from the ground.

36. Crude oil can further refined into a variety of compounds including tar, asphalt, gas, diesel, and kerosene. • Oil refineries boil oil and make it into different things. • 150 oil refineries in the US. • Oil sales measured in barrels..one barrel equals 160 Liters (42 gallons)

37. US uses petroleum more that any other fuel (816 million gallons per day) 22% of worldwide use. • Mostly for transportation. • Petrochemicals: plastics, lubricants, pharmaceuticals, and cleaning solvents. • Top Petroleum Producing Countries: • Saudi Arabia, Russia, US, Iran, China, Canada, and Mexico.

38. Advantages • Easy to transport and use. • Energy dense, cleaner than coal. • Produces less carbon dioxide than coal. • Less sulfur than coal(removed during refining).

40. Disadvantages • Releases trace metals: mercury, lead, and arsenic. • When extracted or transported there is the potential for oil leak or spill. • 2010: Santa Barbara Spill • 1989: Exxon Valdez tanker spill in Alaska • 2005: Blowout of BP Deepwater Horizon oil well off of the coast of Louisiana (206 million gallons)

42. 85% of oil entering marine waterways came from runoff from land and rivers, airplanes, small boats and personal watercraft. • Alaskan Pipeline • 800 mile pipeline was constructed to transport oil. • Inconclusive results of how it has effected wildlife. • ANWR: pristine area (25 million gallons). Could harm wildlife.

45. Natural Gas • With petroleum and also found separately. • 80-95% methane (CH4). • 5-20% ethane, propane, and butane. • Lighter than oil lies above the oil. • Largest use: electricity usage and industry. • Used to produce nitrogen fertilizer, cooking, heating, clothes dryers, and water heaters. • Transported by pipeline, not viable to use for cars. • Liquefied Petroleum Gas (LPG): less energy dense, used in place of natural gas. Can be transported.

47. Advantages • Few impurities when burned. • ½ homes in the US use natural gas for heating. • Emits only 60% as much carbon dioxide as coal.

48. Disadvantages • Emits methane (a greenhouse gas worse than carbon dioxide). • Methane escapes when harvesting natural gas. • When extracted have to drill and open rock: hydraulic fracturing “fracking”. • Fracking: drilling with water, sand, and chemicals. • Need large quantities of water and it releases chemicals that must be disposed .

49. Oil Sands and Liquefied Coal • Oil Sands: slow flowing, viscous deposits bitumen mixed with sand, water, and clay. • Bitumen: tar or pitch not capped with rock. • Mining is energy intensive. • Requires a lot of water. • Lower efficiency, more CO2 emitted.

50. Coal to Liquid (CTL) converting coal to a liquid fuel. • Expensive. • More greenhouse emissions (2x). • Takes a lot of water. • BAD for the environment.