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ENGR 340 Fall 2011 Iowa State University. Electric Power Industry Overview. James D. McCalley Harpole Professor of Electrical & Computer Engineering. Outline. The electric power industry Control centers Electricity markets. 2. Organizations comprising the Electric Power Industry.
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ENGR 340Fall 2011Iowa State University Electric Power Industry Overview James D. McCalley Harpole Professor of Electrical & Computer Engineering
Outline The electric power industry Control centers Electricity markets 2
Organizations comprising the Electric Power Industry • Investor-owned utilities: 239 (MEC, Alliant, Xcel, Exelon, …) • Federally-owned: 10 (TVA, BPA, WAPA, SEPA, APA, SWPA…) • Public-owned: 2009 (Ames, Cedar Falls, Muscatine, …) • Consumer-owned: 912 (Dairyland, CIPCO, Corn Belt, …) • Non-utility power producers: 1934(Alcoa, DuPont,…) • Power marketers: 400 (e.g., Cinergy, Mirant, Illinova, Shell Energy, PECO-Power Team, Williams Energy,…) • Coordination organizations: 9 (ISO-NE, NYISO, PJM, MISO, SPP, ERCOT, CAISO, AESO, NBSO), 7 are in the US. • Oversight organizations: • Regulatory: 52 state, 1 Fed (FERC) • Reliability: 1 National (NERC), 8 regional entities • Environment: 52 state (DNR), 1 Fed (EPA) • Manufacturers: GE, ABB, Toshiba, Schweitzer, Westinghouse,… • Consultants: Black&Veatch, Burns&McDonnell, HD Electric,… • Vendors: Siemens, Areva, OSI,… • Govt agencies: DOE, National Labs,… • Professional organizations: IEEE PES … • Advocacy organizations:AEWA, IWEA, Wind on Wires… • Trade Associations: EEI, EPSA, NAESCO, NRECA, APPA, PMA,… • Law-making bodies: 52 state legislatures, US Congress 3
Transmission and System Operator G G G G G G G G G G G G Independent System Operator G Transmission Operator Transmission Operator Transmission Operator G Today G G Independent System Operator Vertically Integrated Utility 1900-1996/2000 5
What are the North American Interconnections? “Synchronized” 6
What is NERC? • NERC: The North American Reliability Corporation, certified by federal government (FERC) as the “electric reliability organization” for the United States. • Overriding responsibility is to maintain North American bulk transmission/generation reliability. Specific functions include maintaining standards, monitoring compliance and enforcing penalties, performing reliability assessments, performing event analysis, facilitating real-time situational awareness, ensuring infrastructure security, trains/certifies system operators. • There are eight NERC regional councils (see below map) who share NERC’s mission for their respective geographies within North America through formally delegated enforcement authority • Western Electricity Coordinating Council (WECC) • Midwest Reliability Organization (MRO) • Southwest Power Pool (SPP) • Texas Reliability Entity (TRE) • Reliability First Corporation (RFC) • Southeast Electric Reliability Council (SERC) • Florida Reliability Coordinating Council (FRCC) • Northeast Power Coordinating Council (NPCC) 7
What is FERC? • An independent agency that regulates the interstate transmission of electricity, natural gas, and oil. It does the following: • Regulates transmission & wholesale sales of electricity in interstate commerce; • Reviews mergers/acquisitions /corporate transactions by electricity companies; • Reviews the siting application for electric transmission projects under limited circumstances; • Licenses and inspects private, municipal, and state hydroelectric projects; • Protects the reliability of the high voltage interstate transmission system through mandatory reliability standards; • Monitors and investigates energy markets; • Enforces FERC regulatory requirements through imposition of civil penalties and other means; • Oversees environmental matters related to natural gas and hydroelectricity projects and other matters; • Administers accounting and financial reporting regulations and conduct of regulated companies.” • FERC does not: • Regulate retail electricity and natural gas sales to consumers; • Regulate activities of municipals or federal power marketing agencies; • Regulate nuclear power plants (NRC does this); • Address reliability problems related to failures of local distribution facilities; • Consider tree trimmings near local distribution power lines in residential neighborhoods 8
What are ISOs? • The regional system operator: monitors and controls grid in real-time • The regional market operator: monitors and controls the electricity markets • The regional planner: coordinates the 5 and 10 year planning efforts • Also the Regional Transmission Organization (RTO) • They do not own any electric power equipment! • None of them existed before 1996! • California ISO (CAISO) • Midwest ISO (MISO) • Southwest Power Pool (SPP) • Electric Reliability Council of Texas (ERCOT) • New York ISO (NYISO) • ISO-New England (ISO-NE) • Pennsylvania-Jersey-Maryland (PJM) 9
Energy Control Centers • Energy Control Center (ECC): • SCADA, EMS, operational personnel • “Heart” (eyes & hands, brains) of the power system • Supervisory control & data acquisition (SCADA): • Supervisory control: remote control of field devices, including gen • Data acquisition: monitoring of field conditions • SCADA components: • Master Station: System “Nerve Center” located in ECC • Remote terminal units: Gathers data at substations; sends to Master Station • Communications: Links Master Station with Field Devices, telemetry is done by either leased wire, PLC, microwave, or fiber optics. • Energy management system (EMS) • Topology processor & network configurator • State estimator and power flow model development • Automatic generation control (AGC), Optimal power flow (OPF) • Security assessment and alarm processing 10
ECCs: EMS & SCADA Remote terminal unit Substation SCADA Master Station Communication link Energy control center with EMS EMS alarm display EMS 1-line diagram 11
Balancing authorities Performs AGC within designated area. 105 BAs in N. Am.: 67 in EI, 38 in WI, 1 in Texas. Every ISO is a BA. Not every BA is an ISO. 15
Basics of electricity markets • Locational marginal prices (LMPs) • Markets compute the LMPs via an internet-based double auction that maximizes participant benefits • There are 2 separate settlement processes. 16
Locational marginal prices • One for each bus in the network. • Three components – see above. • If the network is lossless, and the transmission capacity is infinite, then all buses have the same LMP. 17
RT LMPs in the MISO and PJM balancing areas 7:20 am (CST) 9/8/2011 19
RT LMPs in the MISO and PJM balancing areas 7:40 am (CST) 9/8/2011 20
Market clearing price Computed as the price where the supply schedule intersects the demand schedule. SUPPLY Price ($/MWhr) DEMAND Quantity (MWhr) 22
Market clearing price Computed as the price where the supply curve intersects the demand curve. SUPPLY Price ($/MWhr) DEMAND Quantity (MWhr) 23
CAISO market design Schedules entire “next-day” 24hr period. Schedules interchange for entire “next-day” 24hr period, starting at current hour, optimizing one hour at a time (1 value per hr) Computes dispatch every 5 minutes. 25
Electricity “two settlement” markets Internet system Energy & reserve offers from gens Which gens get committed, at roughly what levels for next 24 hours, and settlement Day-Ahead Market (every day) Energy bids from loads Generates 100 mw; paid $100. Energy offers from gens Internet system Generation levels for next 5 minutes and settlement for deviations from day-ahead market Real-Time Market (every 5 minutes) Energy bids from loads Generates 99 mw; pays $1. 26
Day-ahead LMPs in ISO-NE balancing areas For hour ending 11:00 am (EST) 9/8/2011 27
RT LMPs in the ISO-NE balancing areas 10:25 am (EST) 9/8/2011 28
RTAncillary service prices in ISO-NE bal areas TMSR=10min spinning rsrv TMNSR=10min non-spinning rsrv TMOR=30min operating rsrv Regulation clearing price is $5.11/MW. Load Zones: Connecticut (CT), Southwest CT (SWCT), Northeast Massachusetts/Boston (NEMABSTN) 10:25 am (EST) 9/8/2011 29
How does wind participate in markets? Demand schedule without wind Point X Price ($/MWhr) Demand schedule with wind Point Y Supply schedule Quantity (MWhr) • “Old” approach #2 • Participates in day-ahead energy • Does not participate in AS or RT • Wind generates what it can • No deviation penalties • Paid based on computed LMP with wind, Point Y below • Marginal unit backed off to compensate • “Old” approach #1 • Participates in day-ahead energy • Does not participate in AS or RT • Wind generates what it can • No deviation penalties • Paid based on computed LMP without wind, Point X below • Marginal unit backed off to compensate 30
How does wind participate in markets? • “New” Midwest ISO approach: • Dispatchable intermittent resource (DIRs) • Participates in day-ahead energy • Makes offer into RT market like any other generator. But one unique DIR feature: • Instead of capacity max offered in by other generation resources, the forecasted wind MW is used as the operation capacity maximum • Units missing “schedule band” of 8% on either side dispatch instruction for four consecutive 5-min periods are penalized. • What are implications? 31
How does wind participate in markets? • What are implications? • Wind is dispatchable! Forecasting is key! • DIRs are expected to provide rolling forecast of 12 five-minute periods for the Forecast Maximum Limit. • If forecast not submitted in time, MISO forecast is used. • Each 5 minute dispatch optimization uses Forecast Maximum Limit based on the following order • 1. Participant submitted Forecast for the interval • Must be less than or equal to the Feasibility Limit • Must have been submitted less than 30 minutes ago • 2.MISO Forecast • Must be less than or equal to the Feasibility Limit • Must have been created less than 30 minutes ago • 3.State Estimator 32
Why is DIR beneficial? • DIRs are more likely to reduce output when LMP is negative because dispatch will instruct them to reduce; there are penalties for not following dispatch. • Inclusion of the DIRs in the RT dispatch will give SCED more flexibility to manage constraints. Therefore, there will be fewer manual curtailments: • Benefits wind for increased MWhrs produced • Benefits to system because wind offers low 35
Very fresh information! From: Amanda Brower [mailto:ABrower@midwestiso.org] Sent: Tuesday, September 13, 2011 2:30 PM To: adv_committee@lists.midwestiso.org; marketsc@lists.midwestiso.org; rscommittee@lists.midwestiso.org; planningac@lists.midwestiso.org Subject: [MISO] DIR Workshop II - Date Changed to October 17 Dear Stakeholders, The date of the Dispatchable Intermittent Resource (DIR) Workshop has changed to October 17, 2011, from 11:00 am to 5:00 pm ET. This workshop will be available from MISO Carmel or St. Paul facilities as well as by dial-in/webcast and recorded. The purpose of this workshop is to expand on the information from the first workshop and give experiences since DIRs were implemented on June 1, 2011. Subject matter experts will be on hand to discuss different aspects of participation by DIRs, including communications, forecasting, operations, markets, and settlements. We encourage participants involved in DIR registration and operation to attend this workshop. Registration is required by October 13 and may be accessed from the MISO website (www.misoenergy.org) directly via the URL below or from the Stakeholder Center tab by selecting: Committees, Work Groups, and Task Forces > Calendar > October 17 > Dispatchable Intermittent Resource (DIR) Workshop II https://www.misoenergy.org/Events/Pages/DIR20111017.aspx 37