Estimates: (2013) Methane Clathrates aka Methane Hydrates or Gas Hydrates another source of unconventional fossil fuels

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1 ES 10 Nonrenewable Energy Resources Oil and Natural Gas Past to Present (31 slides) What are fossil fuels Why use Oil / Natural Gas Drawbacks Where does oil come from? Oil Traps; Source, Reservoir & Cap Rocks Abiotic Oil? Who has the oil & how much is there? How long will it last? Where does US get it s oil? Unconventional sources of oil and gas: Oil Shale, Tar Sands, Methane Clathrates, aka Methane Hydrates, Gas Hydrates Methane Clathrates aka Methane Hydrates or Gas Hydrates another source of unconventional fossil fuels Estimates: (2013) ~500 2,500 Still approx 2 10 X the amount of conventional natural gas Methane Hydrate recovered from Blake Ridge Stored mostly in broad, shallow layers beneath the seafloor, methane hydrate is, by some estimates, twice as abundant as all other fossil fuels combined. The yellow squares show where methane hydrate has already been recovered; the blue dots, where it is thought to exist. 1

2 Estimated ~1,300 trillion cubic ft off N and S Carolina, >60X amount US uses each year (~20 trillion cubic ft/yr) Total US gas Hydrate deposits may be ~320,222 trillion cubic ft, at 10% recovery, enough to last 1600 years Seismic Reflection Profile data on Blake Ridge showing BSR (meters below sea level on left, meters below ocean floor on right) P-Wave rates in hydrates can be as fast as Km/s 2

3 Nonrenewable Energy Resources Part III Coal The Bagger 293 Bucket Wheel Excavator 3:46 Coal I) Coal definition: a biochemical, nonclastic sedimentary rock rich in C, minor S, N, H, metals, silicates II) Formation of Coal: forms from highly compressed remains of land plants; tropical swampy setting lush plant growth bacterial decay burial in anaerobic (low oxygen) conditions buried plant remains exposed to increased pressure & heat over millions of years forming a variety of coal. Earth s most abundant fossil fuel. Most formed~ my BP Land plants appear ~ 400 my BP III) Types of Coal: IV) Supplies and Uses of Coal V) Drawbacks: VI) Mining Coal: VII) Case Study in Ohio VIII) Clean Coal Technology Coal Formation: as heat and pressure increase, various forms of coal are formed. Coal is classified by H 2 O & C content & heat value; formation occurs from left to right getting harder to the right. Quality of coal burned greatly effects emissions. Coal occurs in well-defined beds that are easy to locate compared to underground oil and gas supplies. vvvvvvvvvvvvvvvv 3

4 Supplies and Uses of Coal Total global resources estimated to be ~948 billion tons of coal = to ~ 4.2 billion barrels of oil Source: En Information Administration Identified & unidentified reserves could last world for 214-1,125 years (US will last for ~234 years, at current production) Burning coal generates: 62% of world s electricity, (~51% in US, ~69% in China, ~90% in Poland and South Africa) and 75% of world s steel Using coal to make electricity accounts for ~1/3 of U.S. carbon emissions, China, India, Australia, Greece and Czech Rep. >70% (33% - >70% C emissions) Supplies and Uses of Coal ~27% of world s coal reserves are located in US, 17% Russia, 13% China, 10% India In 2012 US coal exports ~126 mill tons worth >$16 Billion, most since 1991, more than doubled since = 97, 2015 = 41.7 mill tons China is currently starting 2 coal projects/week. Has reserves for ~300yrs at current usage rate, plans to triple capacity by China s Energy demands more than tripled in last 35yrs. (general info about coal) Coal accounts for ~95% of US fossil fuel reserves US burns ~ 1 billion tons of coal/yr Most Environmentally Impacting Fossil Fuel Produces more CO 2 than oil or gas, contributes to more climate change than any other fossil fuel Emits Sulfur & Nitrogen Oxides (SO 2 & NO x ) = forms acids Shows up in spoil banks, rivers, acid deposition Highly disruptive to land surface; alters local topography and habitats. Causes surface and ground water pollution. Human health dangers from mining & burning coal; respiratory diseases Environmental Impacts of Coal Use Sulfur (S) S content of coal can be > 3%; Spoil Banks contain sulfur which reacts with water and air to produce sulfuric acid--polluting streams, lakes and ground water. (Sulfur on the ground) Acid Mine Runoff Acid Deposition sulfur gases (SO 2 ) are produced when coal is burned and mined. (Sulfur gases in the atmosphere) gases poisonous: extremely irritating to eyes and lungs harms fish and aquatic life in streams and lakes acidifies soil and stunt plant growth dissolves rock--corrosion of monuments Ocean Acidification! 4

5 Environmental Impacts of Coal Use Ash / Solid Waste: 5% to 20% of original volume, consists of noncombustible silicate minerals and metals such as Hg, As, Pb, Cr, Cd and Ni causes pollution & health problems. A single coal-fired electric power plant can produce > Million tons/year; most is put into landfills Unreclaimed Surface Mines: susceptible to rapid erosion, mass movement. Sediment deposition occurs in adjacent drainage basins. Case Study: Gallia County Ohio / Sediment Pollution (later) A. Subsurface Mining: dangerous and expensive mine collapse miners contract Black Lung Disease increased cancer risks explosions of natural gas in mines >47,700 deaths in China in last 10 years. How is coal extracted? Due to dangers and expense of subsurface coal mining, surface mining now dominates coal extraction Coal Mining Accidents 443 deaths in US between /24/09 China s coal mining deaths in recent years: 2000: 5,300 deaths. 2001: 5,670 deaths. 2002: 5,791 deaths. There are 50X as many coal miners 2003: 7,200 deaths. in China compared to the US. 2004: 6,027 deaths. 2005: 5,986 deaths. 2006: 4,746 deaths. 2007: 3,786 deaths. 2008: 3,215 deaths Source: State Administration of Work Safety 2012: 1,384 deaths How is coal extracted? B. Surface Mining: far less dangerous and cheaper but causes many more environmental problems, accounts for ~60% of all coal mining. 1. Open Pit: ie. Similar to Bingham Copper Mine in Utah 2. Strip Mining: a. Area Strip Mining ie. In southeastern Ohio, relatively flat terrain, large areas b. Contour Strip Mining used in very hilly areas. 3. Mountain Top Removal Mining (MTR or MTM): explosives used to blast away tops of mountains, in some cases >1,000ft, then large excavators remove the coal. Most common in Appalachian Mountains. Bagger 293 is a giant Bucket Wheel Excavator, used in Germany. It s 315ft tall, 13,500 tons, requires 5 people to operate. One of the largest terrestrial vehicles in the world. 3:46 5

6 Mountain Top mining in West Virginia, 2003 Ridge top debris (often containing selenium, arsenic, coal and sulfur) is typically dumped into adjacent river valleys. ~560 miles of streams have been buried in West Virginia. MTR 8 min moviehttp:// The Office of Surface Mining Reclamation And Enforcement (OSM) was created in 1977 Locations of US Abandoned Mine Land (AML) problems that are eligible for OSM funding. 184 Ohio Coal Mines: 84 have been reclaimed, there is funding for 9 more & 91 are unfunded (no work done as of 2008) 6

7 Grey areas are strip mines that have not been reclaimed in SE Ohio The dark red area is where strip mines have been reclaimed in SE Ohio Case Study: Gallia County Ohio Sediment Pollution 2.2ft/25yrs, 27mm/yr or 27,000mm/1,000yrs E. Slough: 1-3mm/yr Muskingum Mine Reclamation in SE Ohio Forest and Grassland Muskingum Mine Reclamation in SE Ohio Before and after Open Surface Mine reclamation in eastern Tennessee. Photo on left shows a contour mine where they followed a coal seem. Spoil is on the lower hillside. Clean Coal Technology A variety of processes designed to reduce environmental impacts of burning coal IGCC (Integrated Gasification Combined Cycle): Converts coal/water slurry into gas (mostly H and C0 2 ) removes impurities. Carbon capture: capture and store C0 2 and other pollutants Sulfur Dioxide removal Clean coal technologies are increasing in US. 126 Billion is being invested by 2018 Costs 15 20% more to build than conventional design, but they re ~15% more efficient than normal coal fired plants. Japan currently has 18 IGCC plants 7

8 IGCC Important Nonrenewable Energy Sources Floating oil drilling platform Oil drilling platform on legs Water Oil and Natural Gas Oil well Gas well Valves Impervious rock Natural gas Oil Oil storage Water Pipeline Pump Coal Mined coal Underground coal mine Coal seam Geothermal Energy Contour Hot water storage strip mining Geothermal power plant Area strip Pipeline mining Drilling tower Water is heated and brought up as dry steam or wet steam Hot rock Magma Water penetrates down through the rock Environmental Effects of Extracting Resources Steps Mining exploration, extraction Processing transportation, purification, manufacturing Use transportation or transmission to individual user, eventual use, and discarding Environmental Effects Disturbed land; mining accidents; health hazards; mine waste dumping; oil spills and blowouts; noise; ugliness; heat Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat Noise; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat Study Questions/Key Concepts about Coal 1. Describe the shifts in commercial energy resource use in the US since the 1800s 2. What is Coal and how does it form? What are the different types? 3. What are the main advantages and disadvantages of using coal? 4. Where and when did coal deposits form? Other than H and C what other elements naturally occur in coal? 5. How is coal extracted/mined and what are the differences? 6. List and explain several of the environmental impacts of mining, processing and using coal. 7. What does OSM stand for? What is the mission? 8. Describe some of the environmental drawbacks of surface mining that has occurred in south eastern Ohio. 9. What is Clean Coal Technology? ( 300 Years of FOSSIL FUELS in 300 Seconds ) Web Link: Horizontal Wells and Fracking (6.5min) Watch Gasland (2010, by Josh Fox)