Energy and the Environment Lecture Notes PDF
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Bradley J. McPherson
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These lecture notes cover various energy and environmental topics, including societal needs, industrial demands, and historical trends in energy consumption. The document also explores different energy sources and their roles in global development and wealth. Finally, the notes showcase data on energy production trends, including projections for the future.
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Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 1: Introduction & Energy Stats Mr. Bradley J. McPherson P. Eng. Department of...
Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 1: Introduction & Energy Stats Mr. Bradley J. McPherson P. Eng. Department of Societal Need Chemical Engineering Need for us: – To promote high standards of living Housing Transport Communications Food Health – we are healthier now than ever before!! All are benchmarks of an advanced, healthy society … Department of Where are we using electricity? Chemical Engineering Department of Industrial Needs Chemical Engineering Needs of industry: – Raw Materials Food Natural fibers Minerals Natural fuels – Energy Electricity Hydrocarbon fuels Others ?? – People … after J. Sutherland Department of Chemical Engineering Primitive people were 100% hunter gatherers. There was no surplus energy and we survived - uncertainly - from one meal to the next. Often, we were the one on nature’s menu. When we settled and began to grow our own food and used animal labour, and domesticated stock, we began to plan year to year. 75% to 95% of farmers, fed 100% of the people. The others were free to engage in trade and artisanship of various kinds. Water wheels and wind power were used. After the dislocation of the Industrial Revolution, mechanization, and the use of water energy, coal, steam etc., 50% or so of farmers fed 100% of the people. ‘Slave’ child and women labour in mines and factories was tolerated until displaced by machine energy. The rest became educated and expanded the knowledge base. Electricity use became the greatest engine for change and improvement. Today, with ‘totally’ mechanized and efficient operations, 1 to 2% of farmers feed us all. The business of providing energy requires fewer and fewer people and frees more people for more productive social endeavors …. Department of Developed vs Less Developed Regions Chemical Engineering 2019 – 7.6 Billion UN World population prospects – Department of Chemical Engineering 2012 edition UN World population prospects – Department of Chemical Engineering 2021 edition Department of 2024 World Population Projections Chemical Engineering Department of Median age (2024 – 30.7 yrs) Chemical Engineering 2100 Department of Life Expectancy Chemical Engineering Department of Chemical Engineering Department of Infant mortality rates Chemical Engineering Department of World Wealth Chemical Engineering The newsletter of United Nations University and its international network of research and training centres/programmes - ISSUE 44: DECEMBER 2006-FEBRUARY 2007 Department of Chemical Engineering Individual Energy consumption. Adapted from the UNESCO Courier WOW! 28% of the Worlds Population consumes 77% of the energy produced. Department of Technology through the ages Chemical Engineering This increase in consumption has followed the increases in output of machines: Department of GDP and “energy usage” Chemical Engineering We can also see that societal wealth and energy use are directly linked … Department of The Pace of Development Chemical Engineering Britain went through its industrial revolution in about 150 years. It laid the technological and scientific foundation from which other countries were able to push forward in a much shorter time frame. Japan took only 50 years to achieve its major changes, making it a world industrial and economic power. South Korea took only 20 years! China? All ready there? India? Brazil? ….. Department of Chemical Engineering Where do our Primary Energy Supplies Come From?? Department of Chemical Engineering Comparison of world energy production between 1973 and today. Taken from the Key World Energy Statistics 2015/19 & World Energy Resources:2013 Summary International Energy Agency & World Energy Council www.iea.org & www.worldenergy.org OECD – Organization for Economic Co-operation and Development. (represents the “Western World” or the industrialised nations) … OECD MEMBER COUNTRIES Department of Chemical Engineering Twenty countries originally signed the Convention on the Organisation for Economic Co-operation and Development on 14 December 1960. Since then a further ten countries have become members of the Organisation. The Member countries of the Organisation and the dates on which they deposited their instruments of ratification are: AUSTRALIA: 7 June 1971 LUXEMBOURG: 7 December 1961 AUSTRIA: 29 September 1961 MEXICO: 18 May 1994 BELGIUM: 13 September 1961 NETHERLANDS: 13 November 1961 CANADA: 10 April 1961 NEW ZEALAND: 29 May 1973 CZECH REPUBLIC: 21 December 1995 NORWAY: 4 July 1961 DENMARK: 30 May 1961 POLAND: 22 November 1996 FINLAND: 28 January 1969 PORTUGAL: 4 August 1961 FRANCE: 7 August 1961 SLOVAK REPUBLIC: 14 December 2000 GERMANY: 27 September 1961 SPAIN: 3 August 1961 GREECE: 27 September 1961 SWEDEN: 28 September 1961 HUNGARY: 7 May 1996 SWITZERLAND: 28 September 1961 ICELAND: 5 June 1961 TURKEY: 2 August 1961 IRELAND: 17 August 1961 UNITED KINGDOM: 2 May 1961 ITALY: 29 March 1962 UNITED STATES: 12 April 1961 JAPAN: 28 April 1964 KOREA: 12 December 1996 Department of Chemical Engineering Why is an equivalent to tonnes of oil necessary? Department of Chemical Engineering Department of Quick Units Chemical Engineering SI Units: – Energy - Joules (J) 1 J = 1 N × m = 1 kg m2 /s2 – Power – Watts (W) [rate of energy usage] 1W=1J /s Other commonly used units: – Energy – Watt-hours (kilowatt-hours; megawatt-hours) 1 Whr = 1 J/s hr = 1 W ´1hr – Power – horsepower (hp) 1 hp = 746 W Department of Chemical Engineering Department of Total Primary Energy Supply (TPES) Chemical Engineering *Mtoe – Million tonnes of oil equivalent Department of Chemical Engineering TPES – Total Primary Energy Supply Department of 2017 Chemical Engineering Department of 2017 Continued Chemical Engineering Department of Predicting the Future Chemical Engineering Department of World Oil Reserves Chemical Engineering World energy supplies Department of Chemical Engineering Department of Proven Reserves Chemical Engineering Proven Reserves: those which have a reasonable certainty of being recoverable under existing economic & political conditions using today’s technology. Department of Hubbert “Peak Oil” … Chemical Engineering MK Hubbert predicted in 1956 that the US would reach its peak oil production between 1966 – 1971… Even though the peak production rate was seen, World oil reserves continue to be found and exploited … New extraction techniques, unconventional resources etc … Department of Crude Oil Production Chemical Engineering Department of Crude Part II Chemical Engineering Department of Oil: Currently Chemical Engineering As of the 2023 Data: – World production of Crude Oil is now at 4482 MT Canada has fallen to 4th in Crude Oil production behind – United States (#1) – Saudi Arabia (#2), and – Russian Federation (#3) Together these four producers make up ~ 47% of the worlds crude oil production. Department of Canadian Oil Production Chemical Engineering Record high crude oil production largely driven by oil sands: Crude oil year in review 2023 - Statistics Canada (statcan.gc.ca) Department of Crude Oil Prices – Pre COVID Chemical Engineering Closing 12th March 2020: $33.30 (WTI) Department of Crude Price after COVID… Chemical Engineering Closing: 6th Sept 2024: $68.90 (WTI) Department of Crude Forecast Chemical Engineering Department of World Oil Supply Outlook Chemical Engineering Department of Global Natural Gas Chemical Engineering Department of Then Shale Gas came along Chemical Engineering Department of Chemical Engineering Department of Natural Gas Chemical Engineering When Supply far exceeds demand Department of Chemical Engineering Note the effect of the shale gas resource in NA Department of Global Coal Production Chemical Engineering Department of Global Coal Production Part II Chemical Engineering Department of Chemical Engineering Department of Forward Looking – Coal 2025 Chemical Engineering Department of A Tale of Two Opinions Chemical Engineering Department of Global Nuclear Power Plants Chemical Engineering Department of Chemical Engineering Department of Disaster Strikes Chemical Engineering Note decline in 2011 due to Fukushima and shut down of Japanese nuclear power production Department of Nuclear Power Projections - 2026 Chemical Engineering Department of Hydro Electric Power Production Chemical Engineering Department of Hydro Electric Power Production Chemical Engineering Department of Hydro Growth Chemical Engineering Department of Renewable & Alternative Energy Chemical Engineering Department of Geography and Wind Chemical Engineering Department of Wind Chemical Engineering Department of Renewables (Wind) Pt II Chemical Engineering Department of Solar Chemical Engineering Department of Solar adoption trend Chemical Engineering Department of Worldwide Energy Production Chemical Engineering Department of Chemical Engineering Department of Electricity Generation Chemical Engineering Department of Chemical Engineering Department of 2022 World Energy by Source Chemical Engineering Department of Greenhouse Gas Emissions Chemical Engineering Department of Regional CO2 Chemical Engineering 2023 Global Emissions Department of Chemical Engineering Contributors Department of Chemical Engineering Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 2: Introduction to Environmental Effects Bradley J. McPherson P. Eng. Department of Chemical Engineering Department of What is the “Environment” Chemical Engineering What does Environment mean to you? – To most it means: Pristine Waterways Untouched Forested Land Healthy Flora & Fauna Abundant Wildlife Tranquility While all of these are forms of environment, the word itself has many definitions…….. Department of Environment Chemical Engineering Environment: The surroundings or conditions in which a person, animal, or plant lives or operates: - “A perfect learning environment” The Environment: The natural world, as a whole or in a particular geographical area, especially as affected by human activity: - ‘the impact of pesticides on the environment’ Department of Being a regulator Chemical Engineering Regulator for the NB Department of Environment Issue Approvals to Operate & Construct Site visits for compliance & verification audits 10km → Department of Environment Types Chemical Engineering Department of Energy Production Methods Chemical Engineering What are some methods used to produce Electricity? Hydroelectric Dams Thermal Power Plants: Coal Oil Natural Gas Nuclear Power Alternative Technologies Solar / Wind / Geothermal / Biomass Which has the least impact on the Environment? Department of Energy Production Outputs Chemical Engineering The current predictions of anthropogenic global warming (AGW) are primarily blamed on the increase in CO2 and other industrial gasses in the atmosphere. Primary “greenhouse” gasses (GHG) include: – H2O vapour – CO2 – CH4 – N2 O – O3 – CFC’s Potential Outcomes of Energy Department of Chemical Engineering Production Department of Storm Systems Chemical Engineering Sandy – 2012 $76 Billion / Category 1 / Storm Surge Katrina – 2005 $108 Billion / Category 3 / Flooding Wilma – 2005 $26 Billion / Category 2 / Wind Ike – 2008 $38 Billion / Category 3 / Wind Deaths were 195 Worldwide (113 US) Hurricane Patricia in 2015 had the highest ever recorded wind speeds at 345 Km/hr for 1 minute sustained in the Pacific. Hurricane Allen (1980) holds the record for the Atlantic with 190 mph winds. Department of Irene Chemical Engineering Hurricane Irene Year: 2011 Size: Category 3 Wind: 120 mph Deaths: 61 Cost: $16 Billion Department of Hurricane Harvey Chemical Engineering Total Analytics Year: 2017 Size: Category 3 Wind: 130 mph Deaths: 71 Cost: > $70 Billion Department of Hurricane Irma Chemical Engineering Total Analytics Year: 2017 Size: Category 3 Wind: 130 mph Deaths: 61 Cost: > $60 Billion Department of Looking for a Pattern Chemical Engineering Rank Cost (USD) Season 1 ≥ $294.803 billion 2017 2 $172.297 billion 2005 3 $120.425 billion 2022 4 ≥ $80.727 billion 2021 5 $72.341 billion 2012 6 $61.148 billion 2004 7 ≥ $51.114 billion 2020 8 ≥ $50.526 billion 2018 9 ≥ $48.855 billion 2008 10 $27.302 billion 1992 Department of Harvey & Irma Notes Chemical Engineering These Hurricanes became Category 5’s Hurricane Harvey had rainfall amounts of 40+ inches. Hurricane Irma was the strongest storm recorded in the Atlantic for 2017. The damage / economic impact is estimated to be greater than $200 Billion. Though some ignored warnings, evacuations saved lives. Department of Our Planet Chemical Engineering The earth is an extremely complex “machine” … Most of the processes occurring on the Earth rely on the Sun: – Incoming radiation from the Sun warms the Earth’s surface, oceans and atmosphere. – The “average” solar radiance reaching the Earth is about 342 W/m2. – Additional heat comes from radioactive decay of heavy elements deep under the Earth’s surface and high pressure/temperature molten core … Summary of Earth’s Department of Chemical Engineering “Energy Balance”: Solar Input: 342 W/m 2 incoming radiance from the sun: – 77 W/m2 reflected in atmosphere (clouds &/or aerosols); 30 W/m2 reflected by surface (snow/ice, deserts) – total 107 W/m2 (31.3%); All reflected radiation is called the Albedo. – 168 W/m2 absorbed by surface (49.1%); – 67 W/m2 absorbed in atmosphere (19.5%) – Total 235 W/m2 absorbed. For the Earth to be in thermal “equilibrium” the solar input absorbed must be equal to the energy emitted from the surface and atmosphere, otherwise a new stable point will be reached. Department of Earths Energy Balance Chemical Engineering Earth’s balance book … – Surface radiation (black body) accounts for 390 W/m2 – Evaporation and condensation (cloud formation) carries about 78 W/m2 to the atmosphere – Thermal inputs (volcanos etc.) input 24 W/m2 to the atmosphere. – Solar radiance to atmosphere 67 W/m2 – Total: 559 W/m2 – Of this, ~ 235 W/m2 is re-emitted to space as long wave radiation and 324 W/m2 heats the atmosphere and sequentially the surface. Department of Black Body Radiation Chemical Engineering Black body radiation heat transfer: – A black body is a surface that absorbs all the incident EM radiation incident upon it … conversely, it emits EM radiation over the entire spectrum in a perfect manner. – The spectral emissive power of a black body is given by the Planck distribution: C1 C1 = 3.742x108 W m4 / m2 E= é æC ö ù l êexp ç 2 ÷ -1ú 5 C2 = 1.439x104 m K êë è lT ø úû Department of Discussion Chemical Engineering Radiation heat transfer principals can be used to estimate the Earth’s climate or average temperature by examining the heat balance: Rate of Energy Absorption = Rate of Energy Emitted Solar Input ´ (1 – % albedo) = s TEarth 4 Estimate the Earths surface temperature if the albedo were the only factor affecting the absorption of the Sun’s energy. We know atmospheric gasses absorb some of the Sun’s energy incident on Earth as well as some of the energy emitted from Earth back to space. Using the balance shown in the diagram, estimate the Earth’s temperature assuming absorption in the atmosphere. Department of Earth’s Energy Balance Chemical Engineering Department of Thermal Equilibrium Sorta… Chemical Engineering Department of Black Body Emission Rate Chemical Engineering Area under the curve represents the total energy emission rate by the black body: ò ¥ Q= 0 E dl = s T 4 W/ m2 = Stefan-Boltzmann constant (5.67x10-8 W/m2 K4) Department of Black Body Curve Chemical Engineering Black body temperature of the Sun ~ 5800 K Black body temperature of Earth ~ 300 K Department of Climate Trends Chemical Engineering Green House Gas Production What are some natural producers of GHG’s? – Volcanic total CO2 emissions in 2007 ~ 300 million tonnes CO2 (645 Million in 2013) – Total Carbon reserves assumed in the upper mantle of the Earth’s crust under the USA is ~ 100 Trillion Tons Approximately 3.2 Trillion Tons of CO 2 in the atmosphere. Total CO2 world fossil fuel emissions in 2007 ~ 16 billion tonnes of CO2 ~ 21 billion tonnes in 2022 Department of Atmospheric Trends Chemical Engineering Department of Montreal Protocol Gases (CFC’s) Chemical Engineering Department of CO2 Atmospheric Trend Chemical Engineering Department of Radiative Forcing (RF) Chemical Engineering Greenhouse gasses are said to induce a positive “radiative forcing” (RF) in the atmosphere, – i.e., changes in GHG concentration can change the energy balance in the Earth’s atmosphere. RF’s are derived for all influences on global climate: – Changes in solar radiance; – Changes in ice caps or land mass; – Changes in aerosols & cloud cover; – Changes in GHG concentrations … RF Definition: ‘the change in net (down minus up) irradiance (solar plus longwave); in W/m 2 at the tropopause after allowing for stratospheric temperatures to readjust to radiative equilibrium, but with surface and tropospheric temperatures and state held fixed at the unperturbed values’ – IPCC AR4. Pollution Department of Chemical Engineering Air Water Land Are there other types of pollution? Noise Light Visual / Thermal Department of Pollution Consequences Chemical Engineering Water – Drinking / Cooking Air – Breathing / Health Issues Land – Life form habitat / Agriculture Interesting Point: Thermal pollution is the increase in temperature due to human activity: * Concrete jungle * Warmer water due to cooling water requirements Department of Economic / Social Impacts Chemical Engineering 5 TRILLION DOLLARS! – The amount of economic activity disruption from Air Pollution. Projected to rise by 5X by 2060 by the OECD. Air pollution kills between 3 and 5 million people annually. Over 5m in 2013. Not just in developing nations. The United States and Europe see thousands of deaths each year. Department of Air Pollution Deaths Chemical Engineering Department of In the News Chemical Engineering Siberia’s Red River Department of In New Brunswick Chemical Engineering Sisson Mine (Proposed) and Lake Poisoning (Ratonane) Department of Next Lecture Chemical Engineering Did you know???????.......that one (1) coal fired power plant comes online each week in China at a capacity of ~ 500 MW. For Tuesday's lecture on the Regulatory Framework of Energy Production and Climate Change I’d like to answer a few questions: How much coal is required to run a 500 MW power plant for a year at all regulator operational parameters and efficiencies? How much CO2 is produced by burning one (1) ton of coal? Department of Reference Material Chemical Engineering Air Pollution - Our World in Data https://ca.news.yahoo.com/air-pollution-costs-global- economy-221508082.html How Much CO2 Does A Single Volcano Emit? (forbes.com) Daisy World https://www.youtube.com/watch?v=sCxIqgZA7ag Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 3: Regulatory Framework & Climate Change Bradley J. McPherson P. Eng. Instructor Department of Chemical Engineering Department of New Concepts Chemical Engineering Throughout the engineering field we constantly look for a new innovations in the name of process improvement. This can translate to energy efficiencies for us. Department of Energy Efficiency Chemical Engineering Building upgrades – Windows – Insulation – Appliances Smart Grid Industrial Upgrades Transportation Department of Electrical Grid Considerations Chemical Engineering As we become more Energy Efficient, what happens to the demand on the grid? NBPower Projects include Smart Grid and Off Peak Demand Charging. Department of What we want to acheive Chemical Engineering Department of Climate Change Chemical Engineering Is it real? Can we deny that regardless of our impacts on the earth, climates will continuously change? What is directly impacting Climate Change? Greenhouse effect Changes in the suns energy output https://climate.nasa.gov/blog/2910/what-is- the-suns-role-in-climate-change/ Department of GHGs Chemical Engineering The current predictions of anthropogenic global warming (AGW) are primarily blamed on the increase in CO2 and other industrial gasses in the atmosphere. Primary “greenhouse” gasses (GHG) include: – H2O vapour – CO2 – CH4 – N2 O – O3 – CFC’s Department of Climate Interactions Chemical Engineering Department of Climate Change Modelling Chemical Engineering In the 1970’s the scientific community began to theorize about climate change and created the “First Generation Atmospheric General Circulation Model”. (ACMG1) (Fourth version most recent) The more comprehensive “First Generation Coupled Global Climate Model”(CGCM1) was a robust combination of the second atmospheric model (ACMG2) and respective information regarding Ocean, and Heat Flux data. Government of Canada now has a model to predict regional climate issues called the “Canadian Regional Climate Model” (CRCM) which can take a “deeper dive” into specific regional climate change scenarios. https://www.canada.ca/en/environment-climate- change/services/climate-change/science-research- data/modeling-projections-analysis/centre-modelling- analysis/models/regional-model.html Department of “Ice Ages” Chemical Engineering Glacial & Interglacial periods follow fairly predicable cycles in the range of 100k yr or so … Our last Glacial period ended about 10k yrs ago … We find, through temperature and atmospheric gas proxies, that GHG concentrations follow the cycle of melt/thaw … Department of “Ice Ages” Chemical Engineering Department of Ice Age CO2 and Temp Chemical Engineering Department of Solar variance Chemical Engineering We recently reached the low point in solar irradiance as we moved between solar cycle 23 to 24 after a period of quite intense solar activity … see www.solarcycle24.com As the intensity (essentially number of “sun spots”) of a solar cycle can significantly affect the solar input term to the Earth, a weak or strong cycle could significantly alter the Earth’s “energy balance” … Solar cycle 25 started in 2019 and will run to 2030 with it being projected to be weak like cycle 24. Department of Solar Cycle Comparison Chemical Engineering The “Dalton Minimum” was a period of low solar activity and precipitated the “Little Ice Age” … Department of The Little Ice Age Chemical Engineering Significant volcanic activity as well. Department of Design Considerations Chemical Engineering Department of I have an idea….what do I do? Chemical Engineering Concept Preliminary Design Permitting – Detailed Design Capital Investment Construction – Commissioning Operation Decommissioning Remediation Am we missing any phases of an opportunity’s life cycle? Environmental Regulatory Department of Chemical Engineering Processes From the Concept phase, the design engineer must now turn their attention to environmental concerns. Identification of process outputs which could impact the environment: – Air Emissions – Effluent Streams – Solid Waste Material – Noise / Visual / Light Pollution Department of Water Quantity Chemical Engineering Water usage (gal/MW-h) Medium/Average Power source Low case High case case 400 (once- 400 to 720 (pond 720 (cooling Nuclear power through cooling) cooling) towers) Coal 58 530 100 (once- 180 (with cooling Natural gas through cycle) towers) Hydroelectricity 1,430 Solar thermal 1,060 Geothermal 1,800 4,000 Biomass 300 480 Solar photovoltaic 30 Wind power.5 1 2.2 Fossil Fuel Air & Water Department of Chemical Engineering Emissions Air Emissions: – CO2, NOX, SOX, Ozone, and PM – Heavy elements such as Mercury and Arsenic can be emitted and stay in the atmosphere for a substantial period of time. Waste Effluent: – Chemical contamination (boiler or process) – Heat Solids generation is a concern also with ash and EPC by-products such as gypsum. Department of Be Observant – Smoke Density Chemical Engineering Department of Nuclear Power Emissions Chemical Engineering The three main considerations for Nuclear Power Plants are: – Spent Fuel from production – Tailings associated with Uranium mining – Accidental release of heavy contaminants Every nuclear plant releases finite amounts of radioactive gases as part of the daily operation. As a result, people living within an 80 km radius of a plant will see about 0.1 μSv per year while those living at sea level and above will see at least 250 μSv from cosmic radiation. Environmental Regulatory Department of Chemical Engineering Processes Identification of process outputs – Air Emissions – Effluent Streams – Solid Waste Material – Noise / Visual / Light Pollution Does this require an Environmental Impact Assessment Y / N ? If no then proceed to an application for Approval to Construct. Once the Approval to Construct is complete move to an application for an Approval to Operate. There are other requirements for closing a facility as well. Environmental Impact Department of Chemical Engineering Assessment Environmental Impact Department of Chemical Engineering Assessment Part II E.I.A. Continued Department of Chemical Engineering There is a list of “triggers” in Appendix A at the following link: – http://www2.gnb.ca/content/dam/gnb/Departments/en v/pdf/EIA- EIE/GuideEnvironmentalImpactAssessment.pdf The trigger of an E.I.A. for a power plant is from the above document is: – (b) all electric power generating facilities with a production rating of three megawatts or more; Once the E.I.A. review is complete the Minster of Environment will grant or deny approval to proceed. Department of Acts & Regs In NB Chemical Engineering There are three primary Acts that govern the duties associated with the Department of Environment: – Clean Air Act Air Quality Regulation – Clean Water Act Fee for Industrial Approvals – Clean Environment Act Water Quality Regulation http://laws.gnb.ca/en/BROWSECHAPTER?listregulation s=C-6.1&letter=C#C-6.1 Department of Approvals Chemical Engineering Based on the Certificate of Determination of the E.I.A. An Approval to Construct is necessary (in my cases) before you commence construction An Approval to Operate will be necessary if you have any output streams from your facility that will impact the Environment based on an Act or Regulation There are other permits to be aware of: – Wetland and Watercourse Alteration (WAWA) – Ozone Depleting Substances (ODS) – Transportation of Hazardous Waste Department of Reporting Chemical Engineering Based on the nature of the situation at hand. Local reporting (Provincial Reporting) Spill of less than 20L National Scale (The Federal Regulator) Release of Black / Green / White Liquor International Scale (Cross jurisdictional issue) Issue at Point Lepreau Shared international Waterway In New Brunswick we have a shared system with the Federal Government to track reports coming in. Department of Our new Coal Plant Chemical Engineering How much coal is required to run a 500 MW power plant for a year at all regulator operational parameters and efficiencies? A: 1,430,000 tons of coal How much CO2 is produced by burning one ton of coal? 2,5 tons of CO2 (67% Carbon content Coal) http://www.ucsusa.org/clean_energy/coalvswind/brief_coal. html#bf-toc-5 https://www.eia.gov/coal/production/quarterly/co2_article/co 2.html Department of From a 500 MW Coal Case Study Chemical Engineering Water Usage from the study is 2.2 Billion but by my calculation we get 1.855 Billion (using high volume factor from slide 19). Other outputs from the study: 10 000 Tons of SOx and NOx 3.575 million tons of CO2 500 tons of PM (small) 225 tons of Arsenic, 114 tons of Lead, 4 tons of Cadmium What can I tell from this information? 125 000 tons of Ash 193 000 tons of Sludge When we evaluate calculations from other groups we have to always remember what the motive of that group is. Department of General Discussion Chemical Engineering What would happen to the low lying Fredericton GFA should Mactaquac be removed? Department of Next Lecture Chemical Engineering Next lecture topic: - Load Scheduling Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture: Historical infrastructure and the associated framework Bradley J. McPherson Department of Chemical Engineering University of New Brunswick Department of History Chemical Engineering September 4, 1882 – First electric grid in the World with capacity for 800 lights on a DC 110v two wire system. City of Saint John, becomes the first place in New Brunswick with available commercial power in 1884. Department of Saint John NB (1884) Chemical Engineering Department of Emergence of Corporations Chemical Engineering In 1917 multiple private power producers merged to become the first incarnation of the New Brunswick Power Company. In 1948 the New Brunswick Electric Power Commission purchases the NB Power Company and continues to run its assests. Department of Other areas of NB Chemical Engineering Moncton and Fredericton had the same revolution as Saint John. Moncton Gas, Light, and Water Company offers coal gas to residents and businesses and builds a 2000 candlepower and 1000 light dynamo plants in 1886 and 1887 respectively. In Fredericton there was fierce competition between the Fredericton Electric Light Company and Fredericton Gas Company. Department of Rural Development Chemical Engineering The Town of Woodstock had two operating companies but they primarily fed the Iron foundries there until the Woodstock Electric Railway Light and Power Company took over. The Town Council of Campbellton assumed responsibility to bring electricity to the area and built its own infrastructure. To incentive customers it offered free wiring services and the program was so popular, the Town had to build extra generating capacity. Department of Role of Government Chemical Engineering Government recognized that widespread light and power would drive the economy of New Brunswick. First power Act was passed in 1920 “New Brunswick Electric Power Act”. First project of the New Brunswick Electric Power Commission was a $2 Million dam on the Musquash River. Department of First Incident Chemical Engineering In 1923 with plans underway to develop Grand Falls (thought to be one of the best sites on the Saint John River) there was an incident at Musquash. The Dam broke! (earthen berm gave way) Public Confidence was damaged. First Substation in Saint John Department of Chemical Engineering (1921) Department of 1930’s Chemical Engineering Grand Falls has been built by a private company (International Paper Co.) Electricity is coming to major industry and urban centers mostly Rural development is not happening: Why? Cost Prohibitive Low Demand Rural Culture Department of Coal for Thermal Chemical Engineering After the stock market crash in 1929, NBEPC decided to acquire additional stations, build grid capacity, and move to open its first thermal generating station. In 1931 Grand Lake Thermal Generation Station opened to supply the City of Fredericton and the Cotton Mill in Marysville. This plant accessed the indigenous coal from Minto. This was beneficial as it was a close source of fuel and helped prop up the local coal industry. 20 000 tons of coal per year! THATS IT!???? Department of 1930’s Road Map Chemical Engineering International Surplus power to be shipped Power Company to Belledune in 1934 Line to Dalhousie Belledue Dalhousie ??? Newcastler / Chatham Department of 1940’s Chemical Engineering World War II Once the war was over there was a boom cycle in New Brunswick which required more electricity. Burning Diesel fuel in generation units seemed to be the quickest means for production of cheap power. Yet many rural residents had no power and a lot of productive farms remained vacant. Department of Incentivize! Chemical Engineering No one wants to work on a farm anymore in the 1940s but we need food! No one wants to live in a place without power after spending years in urban centers and overseas where people have electricity! So the Government of NB launches: – “A rural electrification plan” Are there any pitfalls with growing to big to fast? Department of Uh - Oh Chemical Engineering Department of Rules during a shortage Chemical Engineering Home: Turn off unnecessary lights Heat hot water sparingly and look for leaks Minimal light in your living area (Vision Req’s) Commercial: No illumination of signs from 8 a.m. to 8 p.m. No electric air heaters Industrial: Switch to night shift if possible Turn off all motor driven machines where possible Department of 1950’s Chemical Engineering More Hydro is built (Tobique Dam) Peak demand is viewed as one of the major planning milestones moving forward 1956 marks first interconnection with Maine.. Department of 1960’s Chemical Engineering Between 1960 and 1975 the electrical consumption of New Brunswick grew 12 %. Our current models suggest 3-4% PER YEAR. Mactaquac comes online brining 600 000 kW of phased in power to the grid at a cost of $128 Million. The head pond raised water levels 130 ft The head pond stretchs for 60 miles. New Age Thermal (1960-1966) Department of Chemical Engineering 1959 – Courtney Bay 50 000 kW Unit 1 1960 – 50 000 kW Unit 2 1966 – 100 000 kW Unit 3 First high T, P plant for the NBEPC Department of Future Planning Chemical Engineering ▪ 1969 - Dalhousie Generation Station. ▪ An unwritten rule in power planning states that: ▪ you will not build a generation plant larger than 1/10 of the overall capacity of your grid. ▪ However, if you have interconnections to other utilities which could take the larger amount of power you can build a bigger plant and benefit from economies of scale. Department of 1970’s / 1980’s Chemical Engineering Interconnections give us…..Coleson Cove Three 355 megawatt units come online burning oil in 1977. By 1982 the price of oil has risen by over 600% due to the energy crisis. Due to instability in the world oil market, we get Point Lepreau Generating Station (PLGS). Department of PLGS Chemical Engineering ▪ Started in 1975 ▪ Completed in 1981 ▪ Selected over 20 other sites: ▪ Bay of Fundy ▪ Relatively Ice Free ▪ Isolated ▪ Work force numbered around 3300 at peak construction. Department of Utility Challenges Chemical Engineering During construction of additional capacity you still need to meet the needs of your users. 1972 the “Worlds First” commercial solid state high voltage direct current converter. This allowed us to import power from Hydro-Quebec without endangering the North American grid. Plants must be converted to burn more than one type of fuel…………….$$$$$$$$$$$$$$$$ Department of Tidbits Chemical Engineering ▪ Nuclear power was conceptualized for New Brunswick as far back as the mid 1950’s. Don’t get discouraged if your idea doesn’t take off on the first try. ▪ Environmental concerns were growing in the 1980s with Nuclear and Thermal power stations. One of the first on land aquaculture studies looked at Rainbow Trout growing in heated ash ponds. Department of 1980s Chemical Engineering PLGS launches in 1983 with the worlds first Candu 600 nuclear plant providing over 30% of NB’s energy. A second interconnection with Hydro-Quebec in 1985 doubles the capacity to receive power from Quebec. This necessitates construction of 400 km of 345 kV high transmission lines. Department of Research for emissions Chemical Engineering In the 1980’s NBPower took over NB Coal. This coal was high in sulfur and caused environmental concern when used as a fuel. An aggressive emissions program began to target the release of Sox and Nox and with the use of limestone could be significantly reduced. The installation of a circulated fluidized bed boiler at the Chatham power station allowed for R&D with low grade fuels. Department of 1990s Chemical Engineering Belledune Thermal Generation Station is permitted beginning in 1989 and comes online in 1993 at a capacity of 490 MW. NB Power permitted 4 sites in Belledune in the event that as plants retire from the generation fleet, that the opportunity to build new generation in the North would exist. Point Lepreau also has capacity for up to 4 nuclear reactors during this time period (and today). Department of NB Infrastructure Chemical Engineering Department of Present Chemical Engineering NBEPC still refurbishes plants if necessary. We demolished both Grand Lake and Dalhousie. Courtney Bay belongs to the Utility again. 265 MW The focus is on demand shifting and reduction. How? Where do we go next? Smart Grid? Off Grid? Department of Reference Material Chemical Engineering https://www.nbpower.com/en/about-us/history https://www.youtube.com/watch?v=3m5qxZm_JqM Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 4: Power Plant Operations & Load Scheduling Mr. Bradley J. McPherson Department of Chemical Engineering University of New Brunswick Department of Power Plant Operation Chemical Engineering The cost of producing electricity can be broken down into: – Capital costs: The cost of constructing a particular type of plant – Operating costs: Maintenance Staffing Fuel A utility will generally run a mix of different plants according to the electrical load requirements at a particular time. Department of The Operations Goal Chemical Engineering Ideal mode for operation: – Operate the plants with the lowest incremental operating costs for the majority of the time. – Bring the plants with higher fuel costs (hence operational costs) on-line on an “as needed” basis. Department of Power Plant Costs Chemical Engineering Large, centralised power stations (> 500 MWe) are expensive to build and have long lead-times: – ~ $1 - 2 Billion for a coal-fired plant (~ 1000 MWe). – $2 - $4 Billion for an equivalent nuclear plant. – Aim for new plants is < $1000/kWe – From planning to commercial operation > 10 years. Huge fossil fuel consumption: – 1000 MWe coal-fired plant will consume ~ 2.8 Million tonnes of coal per year. (Lecture 3 says 1.43 Million for 500 Mwe) – Put that into perspective: 2.8x106 tonnes coal = 2.8x109 kg coal = 2 800 000 000 kg Long payback period: (Belledune 1993) – Plant lifetimes ~ 30 - 50 years (the longer the better). – Small profit margins compared to other investments. Department of 2000 Capital Cost v Production Price Chemical Engineering Levelised Generation Type of Plant Capital Cost (US$/kWe) Cost (US$/MWh) Coal $1,000 - $1,500 $25 - $60 Gas $400 - $800 $37 - $63 Nuclear* $1,000 - $2,000 $21 - $50 Wind** $2,000 - $3,000 $35 - > $140 Solar** (In 2012 the Dependent on location costs are now but generally $5,000 - $150 - >>$300!!! about double Coal) $10,000 and up!!! Levelised Generation Cost: a calculation of cradle-to-grave costs of electricity production (construction, operation, decommissioning etc.) * Decommissioning, and used fuel management costs included. ** Cost of replacement power or spinning reserve not included. Dollar figures obtained from International Energy Agency statistics (~2000) Department of 2010 Cost Projections Chemical Engineering Capital Cost Levelised Generation Cost + Type of Plant (US$/kWe) (US$/MWh) Coal no CC $900 - $2800 $54 - $120 Coal w/ CC $3223 – $6268 Gas $520 - $1800 $67 - $105 $1600 - $5900 Nuclear* $29 - $82 Median ($4100) Wind** - onshore $1900 - $3700 $48 - $163 Wind** - offshore $101 - $188 Dependent on location Solar** $215 - >$600 $5,000 - $10,000 and up!!! + @ 5% discount rate including $30/tonne CO 2 tariff * Decommissioning, and used fuel management costs included. ** Cost of replacement power or spinning reserve not included. Dollar figures obtained from International Energy Agency statistics Projected Costs of Generating Electricity – 2010 Edition Executive Summary Department of 2017 Renewable Cost Projections Chemical Engineering Levelised Generation Cost + Type of Plant Mode (US$/MWh) Solar PV $10 Solar Concentrated $22 onshore $40 - $50 Wind** offshore $90 - $100 Hydro Average of All types $40 +- + @ 5% discount rate including $30/tonne CO 2 tariff * Decommissioning, and used fuel management costs included. ** Cost of replacement power or spinning reserve not included. Dollar figures obtained from International Renewable Energy Agency statistics Projected Costs of Generating Electricity – 2017 Edition Executive Summary Department of 2023 Chemical Engineering Renewable power generation costs in 2023: Executive summary (irena.org) Department of Combined Cycle Chemical Engineering Using the waste heat from one heat engine I can boost the efficiency in a second engine Department of Levelised Cost of Electricity Chemical Engineering Extracted from Projected Costs of Generating Electricity – 2010 Edition Executive Summary Department of Planning Chemical Engineering All of the above necessitate the ability to be able to predict the electricity needs and to plan accordingly for the required production capacity needed. Once a good mix of production types are in place, operating them in the most efficient manner is the goal of the power production utility. Department of Load Variation Chemical Engineering Electrical demand varies as: – Seasons throughout the year; – Time throughout the week; – Time throughout the day. Because electricity cannot be stored, the utility must have enough production capacity available to meet the peak demand. Department of Seasonsal Effects Chemical Engineering Department of Demand Trend Chemical Engineering IESO Market Year in Review 2005 (Independent Electric System Operator - Ontario) Department of Seasonal Variation Chemical Engineering Cooling Heating Department of Daily Variations Chemical Engineering Department of Power Plant Types and Functions Chemical Engineering Base load plants: – Nuclear stations; – Coal-fired stations; – Combined cycle stations; – Hydro stations (spring run-off – see Mactaquac!). Load following or Intermediate load plants: – Oil-fired stations; – Hydro stations; – Wind stations? Peak load plants: – Gas turbine generators; – Hydro stations. Department of Load Scheduling Chemical Engineering Plants with the lowest fuel costs should generally run all the time as “Base Load” power stations. – Large nuclear and coal fired plants traditionally fit into this category Plants with high fuel cost should only be brought on-line as demand requires. These are “Load Following” and “Peak Load” power stations. – Oil-fired, and gas turbine generators traditionally fall into this category. – Hydro can also be considered peak load. Why? Department of Load Carrying and Following Chemical Engineering Department of Operating Constraints Chemical Engineering Not all plants are suitable for base-load operation and other plants are not suitable for peak-load operations. Nuclear and coal-fired plants generally are not easy to bring up and down due to temperature cycling. Likewise, these large plants have large turbines and it is not advisable to load cycle them often which could induce additional stress in the rotors and castings. Gas turbines are traditionally not suited for base-load operation due to the higher fuel costs – this has changed with the more prominent use of combined-cycle plants with higher thermal efficiency. Wind turbines only provide electricity when the wind is blowing so are not suitable base-load or peaking capacity. Department of Reserve Capacity Chemical Engineering Consideration must be given to the possibility of an unexpected shut-down of a base-load plant. This is typically done by ensuring enough “spinning reserve” is available. – Operate all plants at less than full capacity (say 80%); – If one plant goes off-line all the other plants can ramp up to full capacity to fulfill the electricity requirement. If enough spinning reserve is not available then “standby reserve” plants are started. – Hydro plants; – Gas turbine generators. Additional capacity can always be purchased from other utilities, if required … it just costs $$$$ …. Department of Pumped Storage Chemical Engineering A leveling-off of the load-demand curve is possible by using “pumped storage” or by using additional capacity for H2 production through water electrolysis. Essentially, electricity can be stored as potential energy by pumping water to high reservoir (or as hydrogen gas) in the low demand hours and then used to fill some of the peaking capacity in the high demand hours. We’ll pump water at a cost and then spin turbines in high peak times using gravity. Department of Pumped Storage Principle Chemical Engineering Equal areas Department of System Operation Chemical Engineering All plants are connected to the grid frequency and operate at synchronous speed. Grid frequency: – 60 Hz in North America; – 50 Hz in Europe. Increase in power demand is reflected in a drop in grid frequency and the control system initiates power output increases from one or more plants. (more on this later …) Department of Load Forecasting Chemical Engineering As we’ve seen, demand for electricity is exponentially increasing. – Historic growth rates over the past century are about 6% per year. – The actual growth rate in NA is currently ~3-4% Department of Net US electricity generation Chemical Engineering Department of Predicting the Future Chemical Engineering We can make predictions about future energy requirements: Let: – E = energy production – i = yearly fractional increase in energy need dE =Ei dt – Integrating between the current energy generation, Eo, and future energy need gives: Department of Voila Chemical Engineering E t dE E E = i t dt o o ln E = i ( t − t o ) Eo E = Eo exp i ( t − t o ) Department of Annual Production Chemical Engineering Power production has actually followed this trend. We can use the above equation to easily determine the “doubling time”. Assuming the 6% rate of annual increase in power production: Department of Net US electricity generation to 2008 Chemical Engineering Department of Example Chemical Engineering We set: – E1 – energy needs now – E2 – energy needs at some time in the future Dividing the current and future energy needs E 2 Eo exp i ( t 2 − t o ) = = exp i ( t 2 − t1 ) E1 Eo exp i ( t1 − t o ) Department of We need more power…….. Chemical Engineering Setting E2/E1 = 2 and (t2 - t1)= tdoubling Ln(2) = i tdoubling 0.693 tdoubling = i With i at 6% this results in a doubling of electrical capacity every 11.5 years! Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 5: Energy Transformation - Electricity Generation, Transmission & Distribution Mr. Bradley J. McPherson P. Eng. Department of Chemical Engineering University of New Brunswick Thanks to Dr. Eugene Hill (Honourary Research Professor in Electrical Engineering) for some of this material !! Department of Conversions Chemical Engineering Natural resources are converted to our most convenient energy form, electricity. Electricity is instantly and continuously available for general use by the different sectors: – Industry; – Transport; – Domestic; – Business; – Etc. Department of Electrical Production Feedstock Chemical Engineering Currently, the sources of stored energy most used for electricity production include (see Lecture 1): – Coal (40.4%); – Oil (5.0%); – Natural gas (22.5%); – Uranium (10.9%); – Water (16.2%); And to a lesser extent the “renewables”; accounting for 5.0% of electricity production combined : – Wind; – Solar; – Geothermal; – Etc. Department of Generation Cycle Chemical Engineering Conversion of the natural resource (fuel) to useable electricity is a fairly straightforward process … Steam for turbines Combustion gasses for gas turbines Otto/Diesel cycle engines Heat, light Fossil Fuel combustion Electrical Generators Energy Mechanical Heat Engine Energy Transportation, Nuclear Fuel Fission; fusion Motors Industry Department of Upcoming Chemical Engineering Over the next few lectures, we’ll be looking at each of these processes in turn. Common to most processes for electricity production is the transformation of mechanical energy to electrical energy through the use of a generator. However, we’ll see that not all electrical energy production processes require the use of a heat engine … nor mechanical energy conversion. Department of Renewable Sources Chemical Engineering Electrochemical Solar collectors Solar Energy Energy Heat Engine Photovoltic Panels Fuel Cells & Batteries Water Mechanical Electrical Generator Turbine Energy Energy Wind Turbine Transmission & Distribution Department of The How? Chemical Engineering How do we generate electricity? We now remember the basic physics of electricity and magnetism … Department of Voltage Chemical Engineering To generate a voltage, we need three things: 1. A magnetic field with magnetic flux density of B Teslas. 2. A conductor of length L in metres. 3. Relative motion (v in m/sec) between the conductor and the magnetic field (the conductor can move with the magnetic field stationary, or the magnetic field can move with the conductor stationary) Note: 1 Tesla = 1 Weber (Wb) per square meter 1 Wb = 1 V sec = the magnetic flux that produces an EMF of 1 Volt as the flux is reduced at a uniform rate in 1 second. Generating a voltage – the Physics Perspective Department of Chemical Engineering Sliding conducting bar moving at a velocity (v m/sec) on metallic rails; Vertically upward magnetic field of magnetic flux density B Teslas; Voltage induced between the ends of the sliding bar + at terminal 2, - at terminal 1 VISUALIZATION – Conductor cutting magnetic flux. Voltage induced can be expressed as a Cross Product Voltage Induced: e = L (v x B) (or BLv magnitude) (Cross product points in direction of voltage rise, - to +) Generating a voltage – the Practical Perspective Department of (1 - Magnetic Field is Stationary, Move the Coil) Chemical Engineering A coil – nothing more than two conductors in series. But this allows us to change the conceptual viewpoint: from Voltage Induced e = 2 BLv (at this instant) to Voltage Induced e = N dΦ/dt Where: – magnetic flux (Wb) N – number of turns in coil (where above N = 1) [This is Faraday’s Law – if you can cause the magnetic flux linking a coil to change, then a voltage will be induced in that coil] Department of Sine Graph Chemical Engineering This generates a sine wave. The position shown on the last slide is the point of maximum voltage. Department of Currently Chemical Engineering We are still rotating the coil. We want to rotate the magnetic field, that is … we want to rotate the poles. VISUALIZATION – Conductor cutting magnetic flux, or magnetic flux linking a coil. Generating a voltage – the Practical Perspective Department of (2 – Coil Stationary, Move the Magnetic Field or Poles) Chemical Engineering Now we rotate the magnetic poles (called the rotor, or the field.) VISUALIZATION – Magnetic flux linking a coil. The N-turn coil in which the voltage is induced by Faraday’s Law is on the outer shell of the Note: “field winding” required in most structure and is stationary generators since large permanent magnets (called the stator). are seldom used … we create the magnetic flux by applying a voltage/current to induce electromagnetism in the iron core. Department of Stationary Coil Sine Wave Chemical Engineering We do generate a sine wave. The RMS value of the sinusoidal induced voltage is: E = 4.44 f N ΦMAX Volts where f = frequency of the sine wave (60 Hz in NA) If we control ΦMAX we can control E and also the voltage produced at the terminals of the generator. This is done with an Automatic Voltage Regulator (AVR) controlling the voltage on the rotor winding Department of Connect to a Grid Chemical Engineering Generating a voltage – the Practical Perspective Department of (3 – 3-phase generation) Chemical Engineering Consider now that we insert three separate N-turn coils and position them strategically in around the stator … This produces three equal waveforms, only they are out of sync and separated by 120 o. Generating a voltage – the Practical Perspective Department of (3 – 3-phase generation) Chemical Engineering Consider now that we insert three separate N-turn coils and position them strategically in around the stator … This produces three equal waveforms, only they are out of sync and separated by 120 o. What happens if we supply current (apply voltage) to the conductors instead of spinning the rotor? Department of First Problem Chemical Engineering At first look, this doesn’t help because we still need 6 conductors for each load … Department of First Solution Chemical Engineering However, the return (neutral) following the load all comes back to ground, so it may be common for all three loads and carries the total current from each… We’ve reduce 6 conductors to 4 … Department of Second Solution (Balanced Load) Chemical Engineering A more careful look at the current waveform indicates that, if all the resistive loads are the same (i.e. balanced) the current in the neutral line is always zero … so it’s not required and we’ve reduced 6 conductors to 3! At 360o: +Imax + 2(-0.5 Imax) = 0 Department of Wye & Delta Connections Chemical Engineering This is called the Y-connection for obvious reasons. Three-phase generators/circuits may also be configured as Delta- connection … the same principles apply: Department of Delta vs Wye Connection Chemical Engineering Department of Chemical Engineering This is called the Y-connection for obvious reasons. Also called star-connection … Can include the neutral conductor if the loads (R’s) are not all the same, i.e. not balanced. Multiple-pole Rotor and Stator – Department of Chemical Engineering in Practice Multiple-pole generators can combine many windings/electromagn ets to create even higher currents and voltages … Department of Rotor and Stator – in Practice Chemical Engineering Department of Basic Power Distribution Systems Chemical Engineering In order for the electricity generated to reach you from the supplier the following steps are required: – Generation – Transformation (up) – Transmission – Transformation (down) – Subtransmission – Transformation (down) – Distribution Department of Looking at the components in detail Chemical Engineering Generation only takes place at 25 kV or less Transmission should be at high voltage so that the current in the conductors is smaller, conductors are smaller, towers are smaller. Transformers step- up the voltage. Transmission in NB - 138 kV, 230 kV, 345 kV Transmission in Hydro Quebec - 735 kV Bulk power system - where large blocks of power are generated, and transmitted, but no loads are connected here Tie line – ordinary transmission line connecting to Transmission Line a neighboring utility (HQ, PEI, NS, New England) Typical Capacity: 69 kV – 35 MW Subtransmission – 69 kV in NB 138 kV – 150 MW Small GS – we have a few of these. They are 230 kV – 400 MW connected to the Distribution System. 345 kV – 900 MW Department of NB Infrastructure Chemical Engineering Department of Conversions Chemical Engineering R=V/I R = V2/ P R = P / I2 I=P/V Impedance is most directly linked to Resistance (Z =R) All units are: – Power = W – Voltage = V – Current = A – Resistance = Ohms (Ω) Department of Common Definitions Chemical Engineering Current (I) – The continuous movement of electric charge through the conductors of a circuit is called a current or “flow”. Voltage (V) - The force motivating charge carriers to “flow” in a circuit is called voltage. Voltage is a specific measure of potential energy that is always relative between two points Resistance (Ω) – The opposition to motion through a conductor. Department of Transformers Chemical Engineering Magnetic flux is also the basis of operation of transformers: Faraday’s Law gives: VP / VS = NP / NS or V1 / V2 = N1 / N2 There cannot be a DC transformer – why? Steady Field….. The law of Conservation of Power says: VP IP = VS IS Giving: IP / IS = NS / NP or I1 / I2 = N2 / N1 Synchronizing Multiple Department of Chemical Engineering Generators on the Grid The Best Picture – Children’s Swings … One picture of a generator generating a voltage sine wave is a children’s swing. The high point of the swing is the max of the sine wave. The low point of the swing is the min of the sine wave. The best picture of two generators is two children’s swings supported from the same structure. Assume you are on Swing 1. Would you reach out and try to hang onto (synchronize) the second swing if it were going much faster??? Assume you are on Swing 1. Would you reach out and try to hang onto (synchronize) the second swing if the first swing were at a high point and the second swing were at a low point. NO! The only time you could successfully reach out and hang onto the second swing is if they were going at the same speed and only a few degrees apart. Load angle/torque angle, power angle δ = 0 Department of Connecting to the Grid Chemical Engineering Focus on Circuit Breaker CB1. It connects (or it is used to “synchronize”) the generator to the rest of the grid. Department of To Connect you must: Chemical Engineering Three conditions have to be satisfied: 1. The terminal voltage of the generator must be the same as the voltage of the grid. 2. The frequency/speed of the generator must be the same as the frequency of the grid Once CB1 is closed, there is a 3. The phase angle between the natural “synchronizing torque” voltage of the generator and the which inherently tries to keep the voltage of the grid must be zero. generator synchronized to the grid. It takes a large “disturbance” to Then we can close CB1. break this connection. Department of Operating the North American Grid Chemical Engineering There may be a few degrees between the “swing” or generator rotor of one generator in NB and another generator rotor in NB. There may be a few degrees between the “swing” or generator rotor of one generator in NB and a generator rotor in Maine (over our 345 kV tie line) There may be a few degrees between the “swing” or generator rotor of one generator in Maine and a generator rotor in Massachusetts. There may be a few degrees between the “swing” or generator rotor of one generator in Massachusetts and a generator rotor in the New York Power Pool. There may be a few degrees between the “swing” or generator rotor of one generator in the New York Power Pool and a generator rotor in the PJM (Pennsylvania – Jersey- Maryland) System. BUT THEY ALL STAY IN SYNCHRONISM – because there is a natural tendency for the generators to stay in synchronism and because we adjust the Power System Controllers to try to assure that this happens. Otherwise we have a power blackout (see North East blackout of 2004!) Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture: Heat Engines and Thermodynamic Cycles Mr. Bradley J. McPherson P. Eng. Department of Chemical Engineering University of New Brunswick Department of Chemical Engineering In order to generate electricity, we’ve seen that several steps must occur to extract the stored energy in our natural resource … We’ll now consider the “heat engine” term … Thermodynamics! Heat, light Fossil Fuel combustion Electrical Generators Energy Mechanical Heat Engine Energy Transportation, Nuclear Fuel Fission; fusion Motors Industry Department of Thermodynamics Chemical Engineering Thermodynamics is the study of energy (heat) and how it is used to produce tangible things such as work. It stems from some physical laws: – Conservation of energy; – Conservation of mass. It is applied to the production of electricity because most of the methods used to create electricity depend on transferring heat from hot reservoir to a cold reservoir. Department of Chemical Engineering Energy Equation: – The energy equation is a statement of the 1st Law of thermodynamics - conservation of energy; – “Energy cannot be created or destroyed, it may only be transformed from one form into another”. z1g + 21 V12 + u1 + p1v1 + win + qin = z2g + 21 V22 + u2 + p2v 2 + wout + qout Department of Chemical Engineering Potential Energy - this is the energy that a fluid has due to its elevation above a specific point. mzg (J) or zg (J/kg) Total Energy Specific Energy Kinetic Energy - this is the energy that a fluid has due to its velocity. ½ m V2 (J) or ½ V2 (J/kg) Total Energy Specific Energy Department of Chemical Engineering Internal Energy - this is the energy that a fluid has due to the movement and vibration of its individual molecules. U (J) or u (J/kg) Total Energy Specific Energy Flow Work - this is the energy required or emitted from the fluid in moving a slug of fluid of volume V against a pressure p. pV (J) or pv (J/kg) Total Energy Specific Energy Department of Chemical Engineering Mechanical Work - this is the actual work applied to or produced in the system. W (J) or w (J/kg) Total Energy Specific Energy Heat - this describes the heat added to or produced by the system. Q (J) or q (J/kg) Total Energy Specific Energy Department of Chemical Engineering Quite often, some of these terms are negligible and can be omitted. We can also define new functions based on terms that are used frequently. for example - the product of internal energy and pv work occurs often, thus we define the specific enthalpy. h u + pv (J/kg) Department of Chemical Engineering The energy equation, as applied to power production, generally takes the following forms: – In a steam boiler, if elevation and velocity terms are neglected and no work is exchanged the energy equation becomes: h1 + qin = h2 – Thus: qin = h2 - h1 – In an ideal turbine, if elevation and velocity terms are neglected and no heat is exchanged: h1 = h2 + w out w out = h1 − h2 Department of Chemical Engineering We’ve seen that the First Law states that: “Energy can neither be created nor destroyed but only transformed from one form into another”. The Second Law relates the conversion of heat energy to work and its limitations: “No heat engine can generate work without net rejection of heat to a low temperature reservoir” Department of Chemical Engineering The efficiency () of the thermodynamic QREJ process is then related to the useful work Heat Rejected output produced and the total heat input required to produce it. Heat Input (fuel) Work Output work output QIN WOUT = heat input (mechanical work or electricity) Wout = Qin Department of Chemical Engineering The First Law applied to this situation gives: Wout + Qrejected = Qin The Second Law then states that: Qrejected 0 Wout Qin Department of Carnot Cycle Chemical Engineering The Carnot Cycle is the thermodynamic ideal of conversion of heat energy into work. It is best represented on a plot of temperature (K) against the specific entropy (J/kg K) – known as the T-s Diagram. Entropy is a useful quantity in thermodynamics, although it cannot be measured directly. We can imagine it as defining the quality or grade of energy in a fluid. Department of Carnot Cycle Chemical Engineering The total heat input to this system is the complete area under points 1 & 2. (Qin) The work output is the area enclosed by the thermo- dynamic cycle, points 1, 2, 3 & 4. (Wout) This leaves the heat rejected as the area under the temp- erature of heat rejection, points 3 & 4. (Qrejected) Department of Chemical Engineering The efficiency of the cycle is given by: Wout ( TH − TC ) s TH − TC carnot = = = Qin THs TH We can also define the Carnot cycle in terms of available energy and unavailable energy. – Available Energy: the energy available to produce useful work. – Unavailable Energy: the energy rejected to the environment. Department of Thermodynamic Cycles Chemical Engineering The Carnot cycle is the thermodynamic cycle to which all other cycles are compared. It is the most efficient heat engine that can be devised. The higher the temperature of the hot reservoir and the cooler the temperature of the cold reservoir the higher the cycle efficiency. Typically, the high temperature is limited by materials of construction while the low temperature is limited by ambient conditions. Department of Chemical Engineering Typical thermodynamic cycles include: – Rankine Cycle – steam generation and use; – Brayton Cycle – combustion turbines; – Otto/Diesel Cycles – engines; – Refrigeration Cycles: Vapour-compression; Etc … We’ll look at the first two in detail … Department of The Rankine Cycle Chemical Engineering This is the basic cycle for a steam turbine. – What happens in a power plant? Department of Chemical Engineering B&W 450 MW Radiant Boiler for pulverized coal Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 7: Typical Rankine Cycles for Power Generation Mr. Bradley J. McPherson Department of Chemical Engineering University of New Brunswick Department of Chemical Engineering B&W 450 MW Radiant Boiler for pulverized coal Department of Turbine / Generator Set Chemical Engineering Department of Rankine cycles Chemical Engineering We can plot the cycle on a T-s diagram, as we did for the idealised Carnot cycle. The T-s diagram for water incorporates a bell-shaped curve depicting the saturated conditions for water. Department of Chemical Engineering Department of Chemical Engineering In real systems, the Rankine cycle for water-steam for example, the heat is not all input at a constant temperature, thus the efficiency is somewhat less than in the idealised Carnot cycle. For the Rankine cycle: – Heat is added to the water in preheaters and the boiler to produce saturated steam; – The steam is expanded from high pressure to low pressure in the turbine producing work, and; – Heat is rejected through condensation of the low pressure steam. This is typically done under vacuum conditions to minimize the temperature of heat rejection. Department of Saturated Rankine Cycle Chemical Engineering Work lost from Carnot cycle The efficiency of the cycle is still calculated in the same manner: Boiling Wout = Qin Condensation But we can see that the efficiency will be somewhat less than in the Carnot cycle. Department of Saturated Rankine Cycle Chemical Engineering The saturated Rankine cycle follows progressively from Point 1 through 5: 1 to 2 – low pressure water pumped, isentropically (at constant entropy), to high pressure; 2 to 3 – water is heated to saturation isobarically (at constant pressure); 3 to 4 – water is boiled to saturated steam, isobarically; 4 to 5 – steam is expanded in the turbine (ideally isentropic); 5 to 1 – wet steam is condensed back to saturated water (isobarically). Department of Chemical Engineering For the Rankine cycle, work is produced through steam expansion in the turbine and used in pumping (compressing) the water to high pressure. The efficiency can be calculated from the specific enthalpy values of the water/steam at each of these points: Note that we assume some of the work produced is used in compression … h= mwturbine - mwpump = ( h 4 ) ( - h5 - h2 - h1 ) mq h4 - h2 Department of Chemical Engineering Consider a typical steam boiler operating under the following conditions: – Pboiler = 4 MPa; – Pexhaust = 0.005 MPa (5 kPa absolute pressure). How do we determine the enthalpies for points 1 through 5 in order to determine the efficiency of this process? Department of Chemical Engineering The Steam Tables can be used to directly evaluate the enthalpies at each stage of the process. Steam Tables are a tabulation of the thermodynamic properties of sub-cooled, saturated and superheated water/steam as a function of temperature and pressure. Department of Chemical Engineering This saturated steam table shows the thermodynamic properties of the saturated liquid, the saturated vapour and the difference between the two. For enthalpy, these are designated as: – hf enthalpy of the saturated fluid (kJ/kg); – hg enthalpy of the saturated vapour or gas (kJ/kg); – hfg the latent heat of vapourization (h g-hf) (kJ/kg). These are similarly defined for the other parameters: – Specific Volume - (m3/kg) – Specific Internal Energy – u (kJ/kg) – Specific Entropy – s (J/kg K) Department of Chemical Engineering Department of Chemical Engineering Thus, from this saturated steam table we can get the enthalpies required for points 3 and 4. – h3 = hf = 1087.31 kJ/kg; – h4 = hg = 2801.40 kJ/kg; – Tsat = 250.4oC. Likewise, we can go to Pexhaust = 0.005 MPa in the saturation pressure table to determine the enthalpy at point 1: – h1= hf = 137.82 kJ/kg; – Tsat = 32.88oC. Department of Saturated Steam Table Chemical Engineering Department of Chemical Engineering For points 2 & 5 we must consider a sub-cooled liquid and a wet steam mixture respectively. This will generally require interpolation in the steam tables. For Point 2: – P = 4 MPa, T ≈ 33oC (tabulated values are at 2.5 MPa and 5 MPa and between 20oC and 40oC); – h2=141.91 kJ/kg. Department of Chemical Engineering Department of Chemical Engineering For Point 5 we go to the saturated steam tables again and make the assumption of isentropic expansion (ideal case – no frictional losses) in the turbine from Point 4. Thus: s4 = s5 = 6.0701 J/mol K We now interpolate to estimate the quality (x) of the steam at Point 5: s x − s f h x − hf s x = sf + x sfg x= = sfg hfg Thus, x = 0.706 and h5 = 1849.90 kJ/kg Department of Saturated Water Table Chemical Engineering Department of Chemical Engineering Putting these all together: h1 = 137.82 kJ/kg; h2 = 141.91 kJ/kg; h3 = 1087.31 kJ/kg; h4 = 2801.40 kJ/kg; h5 = 1849.90 kJ/kg. h= ( h 4 ) ( - h5 - h2 - h1 ) h4 - h2 h= ( 2801.40 -1849.90) - (141.91-137.82) 2801.40 -141.91 h = 0.356 Department of Chemical Engineering Note that the exit steam quality from the saturated Rankine cycle is low (~70%) indicating a large moisture content (~30% moisture – water droplets). This is undesirable because the water droplets will impinge on the turbine blades and cause increased friction (loss in efficiency) and erosion (premature wear). This deficiency of the saturated cycle can be overcome if we superheat the steam before expanding it in the turbine. Department of Superheated Rankine Cycle Chemical Engineering The superheated Rankine cycle follows progressively from Point 1 through 7: 1 to 2 – low pressure water pumped, isentropically, to high pressure; 2 to 3 – water is heated to saturation isobarically; 3 to 4 – water is boiled to saturated steam, isobarically; 4 to 6 – steam is superheated isobarically; 6 to 7 – steam is expanded in the turbine (ideally isentropic); 7 to 1 – wet steam is condensed back to saturated water (isobarically). Department of Chemical Engineering Consider a steam boiler operating under the following conditions: – Pboiler = 4 MPa; – Pexhaust = 0.005 MPa; – Tsuperheat = 450oC. From the steam tables (same procedure as above) we get: – h1 = 137.82 kJ/kg; h2 = 141.91 kJ/kg; h3 = 1087.31 kJ/kg; h4 = 2801.40 kJ/kg; h6 = 3316.2 kJ/kg; h7 = 2079.0 kJ/kg. – x = 0.80. Department of Chemical Engineering The efficiency is calculated the same way: wturbine - wpump h= q h= ( h 6 ) ( - h7 - h2 - h1 ) h6 - h2 h= ( 3316.2 - 2079.0) - (141.91-137.82) 3316.2 -141.91 h = 0.388 Department of Chemical Engineering The superheated Rankine cycle has: – Led to an improved efficiency of the overall cycle (38.8% vs 35.6%); – Improved the conditions at the turbine exhaust (steam quality of 80% vs 70% for the saturated cycle). Further improvements can be made by going to a superheated-reheated cycle (this is the boiler – turbine system shown earlier). Superheated-Reheated Department of Chemical Engineering Rankine Cycle The superheated-reheated Rankine cycle follows progressively from Point 1 through 10: 1 to 6 – same as the superheated Rankine cycle; 6 to 8 – steam is expanded to an intermediate pressure; 8 to 9 – steam is reheated to the initial temperature at the new, intermediate pressure; 9 to 10 – steam is expanded in the turbine to the original exhaust pressure. 10 to 1 – wet steam is condensed back to saturated water. Department of Chemical Engineering The superheated-reheated Rankine cycle usually operates at higher pressures and higher temperatures than what we have shown for the previous two cycles, but the principles of operation are the same. The efficiency of this cycle is calculated in the same manner, except we must now account for two stages of work production and an additional stage of heating. w HPturbine + w LPturbine − w pump Thus: = qsup erheat + qreheat = (h6 − h8 ) + (h9 − h10 ) − (h2 − h1 ) (h6 − h2 ) + (h9 − h8 ) Department of Chemical Engineering This leads to: – An improved overall efficiency of the process; – A much improved steam quality at the turbine exhaust (this is the main reason for using this cycle – can typically get to 5% moisture or less i.e., > 95% steam quality); – More work output per unit mass of steam. Department of Chemical Engineering CHE 5313 / 6313: Energy and the Environment Lecture 8: Feedwater Heating and Non-ideal Energy Conversion in Turbines and Pumps Mr. Bradley J. McPherson P. Eng. Department of Chemical Engineering University of New Brunswick Regenerative Saturated Department of Chemical Engineering Rankine Cycle If we could extract steam directly from the turbine, as it was producing work, and use it to preheat the feedwater we would get the diagram show on the right. S