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Experience Gained from Electric Power Liberalization Narinder K. Trehan, P.E., Senior Member EEE. US Nuclear Regululoty Commission AbsIracf - The momentum of electric power liberalization (i.e., deregulation) changes from region to region with some regions being more successful than the others. Japan is just starting to liberalize the electric power system The customers in the UK saved f 700 million in one year under electric power liberalization. Other countries such as Australia, Sweden, Norway, and Finland have benefitled fromliberalizationof electric power. In the United States, Federal Energy Regulatory Commission issued Orders Numbers 888 and 889 that started the electric power liberalization in 1996. The Orders mandated electric utilities to open the transmission system on an equal basis to all who utilize it (OASIS). The suppliers can sell electricity directly to lhe consumers using electric utility transmission line. The service of maintaining real time balance between generation and load is performed by load following that is one of the six specified Ancillary Services under FERC Order No 888. Without Load FoUowingService,other service in particular Regulationdoes this function. Regulation is one of the other Ancillary Services that the transmission providers must provide. During the past decade, the demand for electricity in the USA has increased by 35 preen(, whereas, the generation has increased only 18 percent. With electric power liberalization and shortage of transmission lines, open transmission access bas resulted in increased electric power transfers that operate closer to the stability limits. Electric power liberalization has been implemented in other parts of the world mostly with succ-. The World Bank and the Internalional Monetary Fund ask countries receiving their loans to liberalize their state owned power companies as a condition of financial aid. Industry expeN from all regions of the world concluded that the problem is isolated primafily to Calilornia. Index Terns - Liberalization, generators, reactive power, reliability. I. INTRODUCTION transient conditions. A generator tripping offline causes imbalance between generation and load, which can cause a decline in interconnected frequency and voltage. In response to frequency decline, the generators under governor control automatically increase output to restore frequency to 60 Hertz. Generators under automatic generation control (AGC) increase output to restore the imbalance between generation and load within ten minutes. With electric power liberalization and shortage of transmission lines, open transmission access has resulted in increased electric power transfers that operate closer to the stability limits. The momentum of electric power liberalization changes from region to region around the world with some regions being more successful than the others. Experience gained from California could pave the way to successful transformation under electric power liberalization including improving the reliability of the over-stressed electric grid. Electric power liberalization was heavily advertised in California to open the door to lower rates. In response to FERCr 1996 Orders Numbers 888 and 889, the liberalization of electricity supply in California started beginning January I, 1998. The legislation AB-1890promiseda20percentratereduction by April 1,2002 for residential customers. The wholesale electric power market and customers choice program worked for about a year and a half. In the summer of 2000, retail electricity prices in southern California reached all time high, and the shortage of active and reactive power forced rotating blackouts. Electric power liberalization has been implemented in other parts ofthe world mostly with SUCECSS. The World Bank and the International Monetary Fund ask countries receiving their loans to liberalize their state owned power companies as a condition of financial aid. Industry experts from all regions of the world concluded that the problem is isolated primarily to California. Adjustments to real power (Watts) are made by throttle adjustments (governor settings) and adjustments to reactive power(reactivevo1t-ampereorVAR) are made by thegenerator field, voltage regulators and transformer taps. The excitation Operating Reserves under ancillary Services consist of system that controls the reactive power flow by influencing the Spinning Reserve Service and Supplemental Reserve Service. flux level is designed to give close voltage regulation under A Spinning Reserve Service consists of generation 1 1 . OPERATING RESERVES * DISCLAIMER -This paper represena the view of the author and does nal represen1 a Nuclear Regulatory Commission (NRC) psilion on the subjecl covered in the paper. This paper is no1 a substitute for regulalions. and compliance wirh it is not required. Methods and rolutians different from that scl out in the paper could be applied. 0-7803-7525-4/02/$17.00 0 2002 IEEE. 706 synchronized to the power system and responsive to Automatic Generation Control. A Supplemental Reserve Service consists of generation synchronized or capable of being synchronized to the power system that is fully available within ten minutes of the first contingency or load fully removable from the power system within ten minutes of the first contingency. When the operating reserves are low, rotating blackouts are enforced to prevent potential widespread disturbances to the electric transmission grid. 1 1 1 . EXPERIENCE GAINED UNDER ELECTRIC The experience gained under electric power liberalization can POWER LIBERALIZATION be summarized as follows: 1) No new Generating Plants built Some states in the United States had not added major power stations even with increasing demand for power such as emerging digital technology. During the past decade, the demand for electricity in the USA has increased by 35 percent, whereas, the generation has increased only 18 percent. California that had not added a major power station even with an ever increasing demand for power due to a booming economy (emergingdigital technology in the Silicon valley) ran short of electricity. Environmental constraints and stringent air standards have stopped the consuuction of new power plants in the previous years. Since then, about 3000 M W of new generating capacity has been added in California and the peak demand has also decreased. 2) Constrained Power Exchanges from California Out and into California After widespread outages that affected Western states in 1996, the power flow along the Northwest-to-California Interties was decreased by IO% to provide a greater margin of stability. Transmission constraints between northern and southern California within the CAISO control area have resulted in the curtailment of interruptible and firm customer demands both during peak periods and at other times due to power limitations. Path 15 is a group of high-voltage power lines that feed electricity back and forth between Northern and Southern California. IS0 operators have to deal with path congestion that occurs on Path 15 when demand in Northern California draws generation from the southern end of the state. 3) Market Power Exchange (PXJ California replaced the existing decentralized wholesale power marketwithacentralized wholesale power market calledPower Exchange. To create competition on the supply side, the investor owned utilities (IOU) were forced to buy electricity produced by their remaining power plants into the PX. Power Exchange determines the market clearing prices, Day Ahead Market, Hour Ahead Market and the Real Time Market. Day Ahead market is proposed by Federal Energy Regulatory Commission (FERC) as the model of the future. California IS0 will maintain reliableoperationofthe transmissiongrid by matching the demand the supply, according to schedule provided by the PX. Less than 5% would be scheduled by the IS0 in the real time to balance demand and supply. The question arises how PX is going to operate after the clash of California power market. Therefore, the requirements whether the IOUs must buy and sell all their power needs from the PX needs a closer look 4) Inadequate Power Transfer from Hydroelecrric Generating Stations Drought conditions in western pans of the USA had affected the available output of hydroelectric power resources and could notexport electricity to Californiaas they traditionally did. For example, a significant portion of electricity used in California is imported from hydroelectric power in the Northwestern United States. Extreme drought conditions throughout the Pacific Northwest affected the available output of hydroelectric power resources. Reservoir levels in California fell well below normal levels and runoff in the Pacific Northwest fell low. Besides the transmission limitations for importing power into California, the internal capacity linking (path 15) northern and southern California is also limited even if surplus generation from the south is available to help meet the demand in northern California. 5) Lack o f Conservation of Energy by Consumers After seeing the rotating blackouts in California, the residents reduced power consumption by I I percent. The state offers rebates to residents and businesses using energy efficient appliances and lighting. One such program offers a 20 percent rebate on utility bills if they cut power consumption by 20 percent. When power cost increased by 50% or more, conservation showed a surprising jump i.e., market price impacts usage. 6) Long-term Power Purchases Contracts California set up a short term, spot money energy market and investor owned utilities were not allowed to enter long term contracts. The experienced gained from electric power liberalization shows that the utilities should be allowed long- term contracts with the independent power producers. 7) Unavailabiliry of Generating Units due IO Planned and Unplanned Outages The high unavailability of the generating units has resulted fromunits out for maintenance, older units being out for repair, aging of older units, high fuel prices, and air quality restrictions. 8) Reluctance of out-of-state generators to deliver power 707 The power producers would commit only part of their capacity and would maximize their profits when the independent system operator had to buy electricity in real time to meet the electric demand. The utilities could not enter long- term contracts for power. When spot market wholesale prices increased because of higher load demand, the utilities were forced to buy power at higher prices. One independent power producerchargedasmuchas$3,880perMWHinsteadof$273 per MWH during a period of short supply 9) A Five Percent Voltage Reduction The idea of supplying more loads at reduced voltages commonly used on the east coast such as in New England could be used. A 5% voltage reductionessentiallyreduces customers demand and allows a utility to stretch out its supply during times of excess demand. This is one step that allows ISOs to maintain unintermpted service to customers thus avoiding rotating blackouts. The overall savings in power for a 5 percent voltage reduction is about 2 percent. A 5 percent voltage reduction does not affect the house service as standard household appliances and electrical equipment are manufactured with +/- IO percent voltage tolerance. NEMA MG 1-20.45 states that low voltage motors will operate successfully, under running conditions at rated load and frequency with a voltage not more than 10 percent above or below rated voltage. The author looked into the efficiency aspect of running the motor at reduced voltage and determined that there is a negligible effect on the efficiency of a motor mnning at a reduced voltage. IO) Encourage Innovalion in Advonced Technologies during Power Liberalization Due to the limited construction of new transmission lines during transition to regulation, advanced technologies such as Flexible AC Transmission System (FACTS) could be used in maintaining the reactive and voltage control of the electrical grid during heavy power transfers. FACTS technology uses high speed electronic controllers, advanced control technology, fibre optics, and advanced microcomputers to provide the correct transmission voltage, line impedance and the phase angle between them. Static VAR Compensators monitors electric and magnetic fields and adds shunt capacitance or inductive reactance as needed to reduce voltage variations caused by the loads for steady state and dynamic balance. Synchronous condensers, synchronous generators, static VAR compensators (SVCs), and static synchronous compensators (STATCOMs) provide dynamic reactive power support to maintain dynamic and transient stability and transmission capability. Power electronics using thyristors are used to switch power on or off in microseconds. Static VAR (volt ampere reactive) support is provided by line charging, series and switched shunt capacitors. 11) Selling of Fossil, Oil-fied and Cas-fired Generators Unlike other states in the United States, regulation required California to sell its fossil, oil-fired and gas-fired powered generators and had to rely on independent power producers to supply electricity. 12) Replacement of Lorge Power Plants with Distributed Power Resources Some consumers have discovered a way to insulate themselves for the possibility of rolling blackouts. Distributed power resources such as microturbines, solar cells, wind turbines. fuel cells, diesel generators help to smooth the way for this alternate source. IEEE Std. P1547Draft provides criteria for such devices. If fully implemented, distributed power would provide low cost, unintermpted power supply. Distributed power or dispersed power is a modular electric generating unit near the point of use. It ensures electric power during system outages, rolling blackouts. Distributed Power ranges from less than a kilowatt to tens of MW in size. IV. CONCLUSION The momentum of electric power deregulation changes from region to region with some regions being more successful than the others. Experience gained from electric power liberalization could pave the way to a successful transformation. Some states in the United States such as California that had not added a major power station even with an ever increasing demand for power due to a booming economy ran short of electricity. Drought conditions throughout the Pacific Northwest had affected the available output of hydroelectric power sources and could not export the electricity to California as it traditionally did. Due to environmental constraints and public opposition, new power generating stations were not built. Under-scheduling of loads and generation, unscheduled outages, unusual weather conditions and reluctance of out-of-state generators to deliver power fearing that the utilities could no1 pay them could affect the electric power supply. Due to shortage of new transmission lines, and the transmission line constraints could also affect the bulk power delivery system. A limited price control may be the hest way to handle a situation of rolling blackouts and surging wholesale electricity prices. Electric power liberalization has been implemented in other parts of the world with success. The World Bank and the International Monetary Fund ask countries receiving their loans to liberalize their state owned power companies as a condition of financial aid. Industry experts from all regions of the world concluded that the problem is isolated primarily to California. V. ACKNOWLEDGMENTS I would like to thank my Chief Engineer Mr. Jose Calvo whose deep knowledge and insight on electric grid stability contributed greatly to this work. I sincerely wish to express my 708 deep gratitude to him. I also would like to thank Mr. Cornelius H. Holden who provided thoughtful opinion and ideas that significantly improved this paper. VI. REFERENCES I. Narinder K. Trrehan, 2002. Openling Power System Under Reduced Generation Availability.Pmeedinerafthe lEEE Power Enrimerim Suciety, 2. Nvrinder K. Trehan. 1997. Electric Grid Stability and its Impact on Nuclcm Power Generating Srillions. Promedines of the EEE 32d Nuclear - Science SymDmium and Medical 1maeinK Conference. 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