Power System Analysis and Design SI 6 e

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Chapter 1: Introduction © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 0

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Simple Power System l Every power system has three major components – generation: source of power, ideally with a specified voltage and frequency – load: consumes power; ideally with a constant resistive value – transmission system: transmits power; ideally as a perfect conductor © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 1

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Complications l No ideal voltage sources exist l Loads are seldom constant l Transmission system has resistance, inductance, capacitance, and flow limitations l Simple system has no redundancy, so a power system will not work if any component fails © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 2

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Notation – Power l Power: Instantaneous consumption of energy l Power Units Watts = voltage x current for dc (W) k. W – 1 x 103 Watt MW – 1 x 106 Watt GW – 1 x 109 Watt l Installed U. S. generation capacity is about 900 GW (about 3 k. W person) l Maximum load of Champaign/Urbana about 300 MW © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 3

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Notation – Energy l Energy: Integration of power over time; energy is what people really want from a power system l Energy Units Joule = 1 Watt-second (J) k. Wh – Kilowatt-hour (3. 6 x 106 J) l U. S. electric energy consumption is about 3600 billion k. Wh (about 13, 333 k. Wh person, which means on average we each use 1. 5 k. W of power continuously) © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 4

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Power System Examples l Electric utility: can range from quite small, such as an island, to one covering half the continent – there are four major interconnected ac power systems in North American, each operating at 60 Hz ac; 50 Hz is used in some other countries. l Airplanes and Spaceships: reduction in weight is primary consideration; frequency is 400 Hz. l Ships and submarines l Automobiles: dc with 12 volts standard l Battery operated portable systems © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 5

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma North America Interconnections © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 6

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Electric Systems in Energy Context l Class focuses on electric power systems, but we first need to put the electric system in context of the total energy delivery system l Electricity is used primarily as a means for energy transportation – Use other sources of energy to create it, and it is usually converted into another form of energy when used l About 40% of US energy is transported in electric form l Concerns about need to reduce CO 2 emissions and fossil fuel depletion are becoming main drivers for change in world energy infrastructure © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 7

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Sources of Energy – U. S. About 86% Fossil Fuels CO 2 Emissions (millions of metric tons, and per quad) Petroleum: 2598, 64. 0 Natural Gas: 1198, 53. 0 Coal: 2115, 92. 3 1 Quad = 293 billion k. Wh (actual) 1 Quad = 98 billion k. Wh (used, taking into account efficiency) Source: EIA Energy Outlook 2007, Table 1, 2005 Data © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 8

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Electric Energy by Sources, U. S. Source: EIA State Electricity Profiles, 2006 © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 9

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Electric Energy by Sources, Calif. Oregon is 71% Hydro, while Washington State is 76% Hydro Source: EIA State Electricity Profiles, 2006 © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 10

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Electric Energy by Sources, Illinois Source: EIA State Electricity Profiles, 2006 © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 11

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Global Warming and the Power Grid What is Known: CO 2 in Air is Rising Value was about 280 ppm in 1800, 384 in 2007 Rate of increase is about 3 ppm per year Source: http: //cdiac. ornl. gov/trends/co 2/sio-mlo. htm © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 12

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma As is Worldwide Temperature Baseline is 1961 to 1990 mean Source: http: //www. cru. uea. ac. uk/cru/info/warming/ © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 13

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Change in U. S. Annual Average Temperature [°C] = ([°F] - 32°) X 5/9 Source: http: //www. sws. uiuc. edu/atmos/statecli/Climate_change/ustren-temp. gif © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 14

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma But Average Temperatures Are Not Increasing Everywhere Equally [°C] = ([°F] - 32°) X 5/9 Source : http: //www. sws. uiuc. edu/atmos/statecli/Climate_change/iltren-temp. jpg © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 15

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma World Population Trends Country Japan Germany Russia USA China India World 2005 127. 5 82. 4 142. 8 295. 7 1306 1094 6449 2015 124. 7 81. 9 136. 0 322. 6 1393 1274 7226 2025 117. 8 80. 6 128. 1 349. 7 1453 1449 7959 % -7. 6 -2. 1 -10. 3 18. 2 11. 2 32. 4 23. 4 Source: www. census. gov/ipc/www/idb/summaries. html; values in millions; percent change from 2005 to 2025 © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 16

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Eventual Atmospheric CO 2 Stabilization Level Depends Upon CO 2 Emissions Regardless of what we do in the short-term, the CO 2 levels in the atmosphere will continue to increase. The eventual stabilization levels depend upon how quickly CO 2 emissions are curtailed. Emissions from electricity production are currently about 40% of the total © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 17

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Energy Economics l Electric generating technologies involve a tradeoff between fixed costs (costs to build them) and operating costs – Nuclear and solar high fixed costs, but low operating costs – Natural gas/oil have low fixed costs but high operating costs (dependent upon fuel prices) – Coal, wind, hydro are in between l Also the units capacity factor is important to determining ultimate cost of electricity l Potential carbon “tax” is a major uncertainty © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 18

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Ball Park Energy Costs Nuclear: Coal: Wind: Hydro: Solar: Natural Gas: $15/MWh $22/MWh $50/MWh varies but usually water constrained $150 to 200/MWh 8 to 10 times fuel cost in $/MBtu Note: to get price in cents/k. Wh take price in $/MWh and divide by 10. © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 19

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Natural Gas Prices 1990 s to 2008 1 dollar per million BTU = 3. 41 dollars per megawatt-hour © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 20

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Course Syllabus l l l l l Introduction and review of phasors & three phase Transmission line modeling Per unit analysis and change of base Models for transformers, generators, and loads Power flow analysis and control Economic system operation/restructuring Short circuit analysis Transient stability System protection © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 21

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma History of Electric Power Systems l Early 1880 s – Edison introduced Pearl Street dc system in Manhattan supplying 59 customers l 1884 – Sprague produces practical dc motor l 1885 – invention of transformer l Mid-1880 s – Westinghouse/Tesla introduce rival ac system l Late 1880 s – Tesla invents ac induction motor l 1893 – First 3 phase transmission line operating at 2. 3 k. V © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 22

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma History, cont’d l 1896 – ac lines deliver electricity from hydro generation at Niagara Falls to Buffalo, 32 km away l Early 1900 s – Private utilities supply all customers in area (city); recognized as a natural monopoly; states step in to begin regulation l By 1920 s – Large interstate holding companies control most electricity systems © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 23

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma History, cont’d l 1935 – Congress passes Public Utility Holding Company Act to establish national regulation, breaking up large interstate utilities (repealed 2005) l 1935/6 – Rural Electrification Act brought electricity to rural areas l 1930 s – Electric utilities established as vertical monopolies © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 24

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Vertical Monopolies l Within a particular geographic market, the electric utility had an exclusive franchise Generation Transmission Distribution Customer Service In return for this exclusive franchise, the utility had the obligation to serve all existing and future customers at rates determined jointly by utility and regulators It was a “cost plus” business © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 25

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Vertical Monopolies l Within its service territory, each utility was the only game in town l Neighboring utilities functioned more as colleagues than competitors l Utilities gradually interconnected their systems so by 1970 transmission lines crisscrossed North America, with voltages up to 765 k. V l Economies of scale resulted in decreasing rates, so most every one was happy © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 26

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Current Midwest Electric Grid © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 27

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma History, cont’d – 1970 s l 1970 s brought inflation, increased fossil-fuel prices, calls for conservation and growing environmental concerns l Increasing rates replaced decreasing ones l As a result, U. S. Congress passed Public Utilities Regulator Policies Act (PURPA) in 1978, which mandated utilities must purchase power from independent generators located in their service territory (modified 2005) l PURPA introduced some competition © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 28

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma History, cont’d – 1990 s & 2000 s l Major opening of industry to competition occurred as a result of the National Energy Policy Act of 1992 l This act mandated that utilities provide “nondiscriminatory” access to the high voltage transmission l Goal was to set up true competition in generation l Result over the last few years has been a dramatic restructuring of electric utility industry (for better or worse!) l Energy Bill 2005 repealed PUHCA; modified PURPA © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 29

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma Utility Restructuring l Driven by significant regional variations in electric rates l Goal of competition is to reduce rates through the introduction of competition l Eventual goal is to allow consumers to choose their electricity supplier © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 30

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma State Variation in Electric Rates © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 31

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma The Goal: Customer Choice © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 32

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma The Result for California in 2000/1 OFF © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 33

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma The California-Enron Effect WA MT OR ID ND MN SD WY NV WI IA NE UT CA AZ VT ME CO IL KS OK NM TX MO AR NY MI PA IN OH W KY TN VA VA MS AL GA N H MA RI CT NJ DE DC M D NC SC LA AK FL HI electricity restructuring delayed restructuring no activity suspended restructuring Source : http: //www. eia. doe. gov/cneaf/electricity/chg_str/regmap. html © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 34

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma August 14, 2003 Blackout © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 35

Power System Analysis and Design, SI, 6 e Glover, Overbye, Sarma 2007 Illinois Electricity Crisis l Two main electric utilities in Illinois are Com. Ed and Ameren l Restructuring law had frozen electricity prices for ten years, with rate decreases for many. l Prices rose on January 1, 2007 as price freeze ended; price increases were especially high for electric heating customers who had previously enjoyed rates as low as 2. 5 cents/k. Wh l Current average residential rate (in cents/k. Wh) is 10. 4 in IL, 8. 74 IN, 11. 1 WI, 7. 94 MO, 9. 96 IA, 19. 56 CT, 6. 09 ID, 14. 03 in CA, 10. 76 US average © 2017 Cengage Learning ®. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. 36