Chapter 5 Energy: Introduction to Energy and Nonrenewable Energy Sources Think Pair share questions What are the positives about using nonrenewable resources? What are the negatives about using nonrenewable resources? Why have we not switched over to renewable resources? Energy Basics What is energy? the ability to do work What are some forms of energy? chemical, electrical, mechanical, nuclear, light, heat What do we use energy for? transportation, heating, cooking, industry Energy Basics What is the difference between nonrenewable and renewable sources of energy? Once we use up nonrenewable, we can’t get any more What are examples of nonrenewable? oil, natural gas, coal, nuclear Energy Efficiency and Energy Conservation What is the difference? Energy efficiency – the amount of useful energy produced compared to the amount wasted as heat (2nd Law of Thermodynamics); built into the device or system, unavoidable waste Examples of levels of energy efficiency: human body: 20-25% incandescent lightbulb: 5% internal combustion engine: 20-25% steam turbine: 45% Energy conservation – making an effort to reduce the amount of energy used, some waste can be avoided – Examples? Why should we try to increase both? Use of energy resources in the U.S. U.S. has 4.6% of world population; uses 24% of the world’s energy Nonrenewable energy resources removed from the earth’s crust include: oil, natural gas, coal, and uranium www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Fossil Fuels: Coal, Oil ,Natural Gas Fossil fuels that formed from the decay (remains of plants and organisms) that were buried and altered millions of years ago and account for about 80% of the energy generated in the U.S. Coal Coal is sedimentary rock formed from decayed plant material. -most abundant fossil fuel in the world Look on page 121, What happens to begin the formation of coal in a swampy area? Coal 1. 2. 3. 4. What are the four basic stages of coal formation? Coal: the first fossil fuel used Long history of use Can be burned directly to produce a lot of heat in a stove, train engine or factory The dirtiest type of fossil fuel Relatively cheap and abundant Coal Mining Strip mining – very destructive Underground mining, including longwall mining – can be dangerous to the miners Video clip: http://www.youtube.com/watch?v=ylkdUuNOJzw&feature=related Ranks of Coal Lignite: A brownish-black coal of low quality; energy content is less than 4000 BTU/lb Subbituminous: dull black; energy content is 8,300 BTU/lb Bituminous: most common coal is dense and black (often with well-defined bands of bright and dull material); energy content about 10,500 Btu/lb Anthracite: a hard, black lustrous coal, often referred to as hard coal; energy content of about 14,000 Btu/lb www.uvawise.edu/philosophy/Hist%20295/ Powerpoint%5CCoal.ppt Acid Mine Drainage The impact of mine drainage on a lake after receiving effluent from an abandoned tailings impoundment for over 50 years Relatively fresh tailings in an impoundment. http://www.earth.uwaterloo.ca/services/whaton/s06_amd.html The same tailings impoundment after 7 years of sulfide oxidation. The white spots in Figures A and B are gulls. Cutting edge research: Clean Coal Technology (CCT) Involves carbon capture and storage, washing coal to remove pollutants, use of devices to purify air as it leaves the plant, convert solid coal to a gas (cleaner, more efficient) Video clips: http://www.cleancoalusa.org/ Advantages and Disadvantages of Coal Pros • Most abundant fossil fuel • Major U.S. reserves – contributes to energy independence • 300 yrs. at current consumption rates • High net energy yield Cons • Dirtiest fuel (produces particulate matter, carbon dioxide and sulfur dioxide) • Mining causes major environmental degradation • Major threat to health © Brooks/Cole Publishing Company / ITP www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Oil A thick, black liquid formed from buried remains of microscopic marine organisms. Deposits of crude oil often are trapped within the earth's crust and can be extracted by drilling a well Crude oil: complex liquid mixture of hydrocarbons, with small amounts of S, O, N impurities Example: the Deepwater Horizon was drilling to get oil Oil Crude oil is transported to a refinery where distillation produces petrochemicals One example: TransAlaska Pipeline Oil refinery – notice the tall towers…. Oil refineries in the southern U.S. Info for Oil: Infrastructure already in place Risk of spills www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Natural Gas – another fossil fuel Fossil fuel formed from marine organisms that often is found in tilted or folded rock layers. Mixture of gases •50–90% Methane (CH4) •Ethane (C2H6) •Propane (C3H8) •Butane (C4H10) •Hydrogen sulfide (H2S) www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Sources of Natural Gas • Russia & Kazakhstan - almost 40% of world's supply. • Iran (15%), Qatar (5%), Saudi Arabia (4%), Algeria (4%), United States (3%), Nigeria (3%), Venezuela (3%); • 90–95% of natural gas in U.S. domestic (~411,000 km = 255,000 miles of pipeline). www.bio.miami.edu/beck/esc101/Chapter14&15.ppt What do we use natural gas for? 1. 2. 3. 4. 5. Produce electricity Heat homes (inside homes, water heater) Industry (heat for warmth and producing things) Vehicles Cooking Hydraulic Fracturing or Fracking Technique used to get gas out from underground – pump water into spaces to increase pressure Fracking can cause groundwater contamination and earthquakes www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Fossil Fuels: Coal, Oil, Natural Gas 1. 2. 3. What are 3 ways you can conserve (avoid wasting) fossil fuels? Energy from Atoms Nuclear energy is an alternate energy source produced from atomic reactions. Energy is released during fission reaction when a heavy atom is split into lighter atoms. Fusion occurs when two atoms come together to form a single atom. Nuclear Energy In a conventional nuclear power plant, a controlled nuclear fission chain reaction heats water to… produce high-pressure steam that… turns turbines which… generate electricity Nuclear Energy Nuclear fission – splitting of an atom Once an atom splits, neutrons cause other atoms to split – a chain reaction occurs In a nuclear power plant, the chain reaction is kept under control (using control rods), and the heat is used to generate electricity Most common fuel used is uranium – a nonrenewable heavy metal that comes from underground www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Controlled Nuclear Fission Reaction cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Radioactivity • Types • Alpha particles consist of 2 protons and 2 neutrons, and therefore are positively charged • Beta particles are negatively charged (electrons) • Gamma rays have no mass or charge, but are a form of electromagnetic radiation (similar to X-rays) • Sources of natural radiation • • • • • Soil Rocks Air Water Cosmic rays www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Relative Doses from Radiation Sources Unit for measuring radiation dose: millisievert (mSv) cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt Effects of Radiation • Genetic damages: from mutations that alter genes • Genetic defects can become apparent in the next generation • Somatic damages: to tissue, such as burns, miscarriages & cancers www.bio.miami.edu/beck/esc101/Chapter14&15.ppt www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt Radioactive Waste 1. Low-level radiation (Gives of low amount of radiation) • Sources: nuclear power plants, hospitals & universities • 1940 – 1970 most was dumped into the ocean • Today deposit into landfills 2. High-level radiation (Gives of large amount of radiation) • Fuel rods from nuclear power plants • Half-time of Plutonium 239 is 24000 years • Safe method of storage is difficult – may be stored in pools, or dry casks on land www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Yucca Mountain Was going to be the nation’s repository for nuclear waste – this plan has been canceled www.geology.fau.edu/course_info/fall02/ EVR3019/Nuclear_Waste.ppt Nuclear Power Plants in U.S. cstl-cst.semo.edu/bornstein/BS105/ Energy%20Use%20-%203.ppt Three Mile Island • March 29, 1979, a reactor near Harrisburg, PA lost coolant water because of mechanical and human errors and suffered a partial meltdown • 50,000 people evacuated & another 50,000 fled area • Unknown amounts of radioactive materials released • Partial cleanup & damages cost $1.2 billion • Released radiation increased cancer rates. www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Chernobyl • April 26, 1986, reactor explosion (Ukraine) flung radioactive debris into atmosphere • Health ministry reported 3,576 deaths • Green Peace estimates32,000 deaths; • About 400,000 people were forced to leave their homes • ~160,000 sq km (62,00 sq mi) contaminated • > Half million people exposed to dangerous levels of radioactivity • Cost of incident > $358 billion www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Effects of Chernobyl nuclear disaster Fukushima disaster – Japan, March 2011 before Earthquake, followed by tsunami – subsequent loss of power to cool reactors, plus fire at plant Use of Nuclear Energy • U.S. phasing out - ??? • Some countries (France, Japan) investing increasingly • U.S. currently ~7% of energy nuclear • No new U.S. power plants ordered since 1978 • 40% of 105 commercial nuclear power expected to be retired by 2015 and all by 2030 • North Korea is getting new plants from the US • France 78% energy nuclear www.bio.miami.edu/beck/esc101/Chapter14&15.ppt www.bio.miami.edu/beck/esc101/Chapter14&15.ppt Energy & Mineral resources Comparison of Supplies of Nonrenewable Energy Sources: garnero101.asu.edu/glg101/Lectures/L37.ppt Self Check 1. 2. 3. 4. Explain why coal, oil, and natural gas are fossil fuels. Explain why fossil fuels are considered to be nonrenewable energy resources. Describe two disadvantages of nuclear energy. Think Critically: Why are you likely to find natural gas and oil deposits in the same location, but less likely to find coal and petroleum deposits at the same location?