Fossil Fuels: The Major Energy Sources and Environmental Impact

1. Chapter 18 Fossil Fuels and the Environment

2. Fossil Fuels Forms of stored solar energy created from incomplete biological decomposition of dead organic matter 3 Major fossil fuels provide about 90% of worldwide energy consumed • Crude Oil • Natural Gas • Coal 70-80% of world’s primary energy comes from oil and natural gas with 2 major exceptions: - Asia gets more of its energy from coal than rest of world • Middle East gets almost all its energy from oil and gas See graph Figure 18-3 page 366

3. World Energy Consumption by Primary Sources2004

4. Crude Oil and Natural Gas • Crude Oil • Naturally occurring petroleum, normally pumped from wells in oil fields • Refinement of crude oil produces most of the petroleum products we use today • Natural Gas • Naturally occurring gaseous hydrocarbon generally produced in association with crude oil or from gas wells • An important efficient and clean burning fuel commonly used in homes and industry

5. 2 Types of Oil and Gas Traps – Anticline and Fault

6. Oil in the 21st Century • The U.S has an energy problem caused by dependence of fossil fuels, especially oil • Maximum global production is expected between 2020 and 2050 • The challenge is to plan for the decline in oil supply and shift to alternative energy sources

7. Proven World Oil Reserves 2004

8. Major Trade Routes for World Oil 2004

9. Consumption of Oil Per Person in 2005 (barrels per person)

10. Petroleum • NEED 2014 info on Petroleum p. 30 - 33 of NEED Energy info book • Petroleum Fact Sheet 2014 NEED

11. Natural Gas • Considered a clean fuel as burning it produces fewer pollutants than burning oil or coal; causes fewer environmental problems • Must be transported by pipelines, more pipelines built in last few decades • Natural gas found with petroleum used to be burned off as a waste product (still happens) • Possible transition fuel to more alternative sources

12. “Fracking” of natural gas from shale • AKA hydraulic fracturing: equipment used to drill, then high pressure water and chemicals are used to fracture the shale and extract the natural gas • Controversial as lots of fresh water goes in and contaminated waste water produced

13. Hydraulic Fracturing Animations • Fracking for Natural Gas explained by Marathon Oil • Pros and Cons of Fracking

14. Coal Bed Methane (Natural Gas) • Extracting methane that is stored with the coal deposits on the surfaces of organic material in the coal • Drawbacks : - large volumes of high saline waste water - migration of methane could contaminate groundwater or residential areas - noise pollution from equipment used at well sites

15. Methane Hydrates • White ice-like compound made up of molecules of methane gas trapped in “cages” of frozen water in the sediments of the deep seafloor • Methane hydrates must stay at very cold temp and high pressure or decompose rapidly • NOAA methane hydrate release animation

16. Methane Hydrates (Continued) • Potential energy resource with approximately twice as much energy as all the known natural gas, oil, and coal deposits on Earth • Hard to mine safely at these depths (often > 1km deep!) and would need to develop a method to produce and transport • DOE's info on methane hydrate

17. Environmental Effects of Oil and Natural Gas p. 371 and 372 • Recovery: land use, damage to fragile ecosystems, water contamination, air pollution, waste disposal problems, land subsidence, aesthetic degradation (wells, pipelines, roads, offshore oil-drilling platforms) • Refining: soil, water and air pollution • Delivery and Use: oil spills, air pollution from combustion of fuels to power automobiles, produce electricity, etc.

18. Arctic National Wildlife Refuge (ANWR) in North Slope, AK – controversy over scenery, wildlife, and oil

19. New Technology that could reduce the impact of oil fields in the Arctic – from those in favor of ANWR drilling – ANWR 2016 update USGS

20. Propane • C3H8 gaseous but compressed to liquid (LPG) • Found with natural gas and petroleum deposits • NEED Propane Fact sheet at http://www.need.org/Files/curriculum/infobook/PropaneS.pdf

21. Coal • Solid, brittle, carbonaceous rock that is one of the world’s most abundant fossil fuels. • 4 Types of coal • Lignite • Sub-bituminous • Bituminous • Anthracite • Classified according to energy content as well as carbon and sulfur content – anthracite has most energy but also has most sulfur! More coal info

22. How coal is formed from buried partially decomposed vegetation (peat)

23. World Coal Reserves in 2004 (in billions of tons)

24. Coal Areas of the U.S.

25. Sulfur and Energy Content of Coal Types • Lower the sulfur content, the less sulfur dioxide emitted and more desirable it is for power plants. However most of low sulfur coal in U.S. is also low-energy: low grade lignite and subbituminous coal • Power plants using higher sulfur, higher-energy bituminous coal or higher grades of lignite and anthracite treat the coal to lower sulfur content before, during, and after combustion to reduce air pollution

26. Coal Mining and the Environment • Strip Mining • A surface mining process in which the overlying layer of soil and rock is stripped off to reach the coal Mining types and techniques from University of Kentucky

27. Mining Types

28. Underground Mining • Associated with environmental problems including acid mine drainage, land subsidence and coal fires

29. Other Pollutants From Mining • Mining in general is responsible for some of the largest releases of heavy metals • Smelting process to extract metal from ores is associated with highest exposures and environmental releases including lead and mercury • Occupational Knowledge International

30. Transport of Coal • expensive to convert coal at site to electricity, synthetic oil or synthetic gas because all require lots of water • trains provide low cost transport • coal-slurry pipelines – pipelines expensive to build and must have lots of water

31. Managing Coal Resources and Reducing Pollution • The Future of Coal • Many new technologies designed to reduce emissions of sulfur dioxide and nitrogen oxides from coal burning listed on pp 380; 554-555 See this link: Clean Coal Technologies • Ex: Scrubbing removes sulfur dioxides but produces sludge waste • Allowance Trading • Reduces pollution • EPA grants utility companies tradable allowances for polluting

32. Clean Coal Technology

33. Combined Cycle Coal Plant • Uses part Natural Gas and part Coal to generate electricity • GE’s Combined Cycle plant

34. Recycling Waste Products from Coal-burning Power Plants CCR’S(Coal Combustion Residuals) • Fly Ash • Bottom Ash • Boiler Slag • Flue Gas Desulfurization Material (FGD) • More info on each of these waste products

35. Oil Shale • Fine-grained sedimentary rock containing organic matter – called kerogen • Converted to oil by destructive distillation at very high temperatures (500o C/900oF). • The oil is a synfuel (synthetic fuel) – liquid or gaseous fuels derived from solid fossil fuels

36. Oil Shale locations • Found in Green River Formation in Colorado, Utah, Wyoming • Options of surface (90% of shale oil extracted) or subsurface mining (60% extraction rate), but volume of waste material will exceed volume of shale mined due to added pore spaces. Creates waste disposal issues.

37. Tar Sands • Sedimentary rocks or sands impregnated with tar oil, asphalt or bitumen (right) • Petroleum too viscous to be removed by pumping or other methods, so… • Sands first mined, then washed with hot water to remove the oil • 75% of world’s tar sand deposits are in Athabasca Tar Sands near Alberta, Canada (Nat. Geo’s before and after pic right) • Mined in open pit mine in permafrost muskeg swamp – difficult to restore; mined sand takes up more volume than unmined material

38. Sierra Club Video on Tar Sands • Tar Sands Sierra Club Video

39. U.S. Electricity Generation by Energy Source from EIA.gov • In 2013, the United States generated about 4,058 billion kilowatt hours of electricity. About 67% of the electricity generated was from fossil fuel (coal, natural gas, and petroleum), with 39% attributed from coal. • In 2013, energy sources and percent share of total electricity generation were: • Coal 39% • Natural Gas 27% • Nuclear 19% • Hydropower 7% • Other Renewable 6% • Biomass 1.48% • Geothermal 0.41% • Solar 0.23% • Wind 4.13% • Petroleum 1% • Other Gases < 1%