However, the situation by 2008 will be tighter. NYISO expects peak demand to increase by 1,370 MW, and capability may actually decline because of plant retirements. Thus, reserve margins could be lower than the standard requires, even without the retirement of either of the Indian Point reactors.
In addition to the excess capacity in the western section of the state and the Upper Hudson Valley region, some underutilized capacity might be found in the neighboring control areas: the mid-Atlantic counterpart to the NYCA, known as “Pennsylvania Jersey Maryland” [PJM]; Canada; and New England. In the past 5 years, the NYCA imported approximately 10 percent of its energy requirements from PJM and Canada. The annual energy exchange between the NYCA and New England is essentially neutral. It is difficult to determine exactly how much capacity might be found (much of the key information is proprietary) and whether the
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs 3 Generation and Transmission Options When an electric generating plant is retired, it usually is replaced with other generating capacity—perhaps a new generating unit or a new transmission line from an area with surplus power. Either or both reactors at the Indian Point Energy Center could be replaced with these options. However, demand growth projected by the New York Independent System Operator (NYISO) for the New York City area (see Chapter 5) would require considerable additional capacity even without the retirement of Indian Point. That growth can be moderated, as discussed in Chapter 2, but it is likely to be significant. The supply options discussed in this chapter must be adequate to handle growth, retirements of existing capacity, and the potential replacement of Indian Point, if reliability of supply is to be maintained. This chapter discusses the options for generation, transmission infrastructure, and reactive power in New York. Distributed generation is discussed in Chapter 2 with other end-user options because it generally is not dispatchable by NYISO and is not included in reliability calculations. EXISTING GENERATING CAPACITY New York’s existing electricity generation is a diverse supply resource, including natural gas, oil, coal, hydroelectric, nuclear, and wind power, as described in Chapter 1. However, much of this generation is far from the large and growing load centers of the New York City area. Western New York (New York Control Area [NYCA] Zones A through E) has surplus of capacity, while New York City (Zone J) is an importer of power, as shown in Table 3-1. The Lower Hudson Valley (Zones G through I) currently has a capacity well above its load, but that will more than disappear if Indian Point is closed. Long Island also must have imported power available to meet its reserve requirement (NYISO, 2005b). The NYCA, taken as a whole, had approximately 1,300 megawatts (MW) of excess summer resource capability in 2005, representing an excess reserve margin of 3.5 percent.1 TABLE 3-1 Approximate (Noncoincident) Summer Peak Load and Capacity in New York State, by Region Zone Peak Load (MW) Capacity (MW) West (A through E) 8,900 14,430 Upper Hudson Valley (F) 2,180 3,470 Lower Hudson Valley (G through I) 4,490 5,490 New York City (J) 11,150 8,940 Long Island (K, outside of NYC) 5,050 5,180 NOTE: Numbers are approximate and based on the summer of 2004. SOURCE: NYISO (2005a). However, the situation by 2008 will be tighter. NYISO expects peak demand to increase by 1,370 MW, and capability may actually decline because of plant retirements. Thus, reserve margins could be lower than the standard requires, even without the retirement of either of the Indian Point reactors. In addition to the excess capacity in the western section of the state and the Upper Hudson Valley region, some underutilized capacity might be found in the neighboring control areas: the mid-Atlantic counterpart to the NYCA, known as “Pennsylvania Jersey Maryland” [PJM]; Canada; and New England. In the past 5 years, the NYCA imported approximately 10 percent of its energy requirements from PJM and Canada. The annual energy exchange between the NYCA and New England is essentially neutral. It is difficult to determine exactly how much capacity might be found (much of the key information is proprietary) and whether the 1 The NYISO (2005b) report Comprehensive Reliability Planning Process lists total capability of 38,772 MW and an expected peak demand of 31,960 MW (demand actually peaked at 32,075 MW in July 2005). The required capability with an 18 percent reserve margin is 37,395 MW. Thus there was an excess capability of 1,327 MW.
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs transmission capacity (discussed later in this chapter) to deliver it to the New York City area is available. In addition, with demand growing elsewhere and more retirements likely, current excess capacity may not be available in a few years. Currently, at most only a few hundred megawatts could be imported to the New York City area during peak periods, and demand growth is likely to account for that in a few years (Hinkle et al., 2005; discussed in Chapter 5 of this report). Additional power could be imported during peak periods if the transmission grid was upgraded (and in nonpeak periods even without upgrades). POTENTIAL NEW GENERATING CAPACITY Having concluded that the existing generation and transmission system could make little contribution to replacing Indian Point, the Committee on Alternatives to Indian Point for Meeting Energy Needs turned to the question of potential new generation. The committee examined 18 potential alternative generating technologies for possible use in the Lower Hudson Valley/New York City region, including 5 natural-gas-based options, 5 coal-based options, 2 biomass options, 3 wind options, 2 solar options, and 1 advanced nuclear power plant option. Many of these technologies were determined to be unlikely to make a significant contribution to the power needs of the New York Control Area in the time frame of this study. Appendix D-1, “Cost Estimates for Electric Generation Technologies,” lists all of the technologies considered with their key cost elements, and Appendix D-2, “Zonal Energy and Seasonal Capacity,” presents data for comparisons of zonal energy and seasonal capacity, including the use of supplemental oil with gas turbines. Technologies Considered Potential generating technologies include natural-gas-fired units, coal-fired units, biomass-powered units, wind systems, solar-based technologies, and advanced nuclear re-actors. Table 3-2 lists the technologies considered and some of their characteristics. Natural Gas The use of natural gas as a relatively clean fuel for electric power generation has grown rapidly over the past 20 years as the supplies became more available from various areas of the United States and Canada compared with the period of the mid-1970s. Appendix D-3, “Energy Generated in 2003 from Natural Gas Units in Zones H Through K,” shows power generation from natural gas in the New York City area in 2003 and 2004. It also shows that replacing all of Indian Point’s power with natural gas would require about a one-third increase in the consumption of gas for electricity. The technologies that are currently used to convert natural gas to electricity are much more efficient and reliable than earlier versions. The environmental benefits of natural gas relative to other fossil fuels are also a big advantage. Unlike coal, the combustion of natural gas emits no oxides of sulfur, and emissions of nitrogen oxides can be held to standards through stack-gas emission-control systems. Current supplies of natural gas cannot always accommodate current, let alone increased demand for the product. The owners of gas-fired units in New York State are frequently required to power their gas-fired units with oil products during cold weather periods since the residential sector, with firm delivery service, has priority over the utility sector, which typically has interruptible service tariffs. Generators with backup fuel systems have been providing nearly 20 percent of the electric production derived from the gas turbine facilities in New York State (NYISO, 2005b). For future natural gas turbine facilities to contribute to the electric system during cold weather periods, they should have either backup fuel capability with adequate fuel inventory or firm natural gas pipeline capacity for these periods. Oil tanks could necessitate a larger site footprint, and the combustion of the oil would change the characteristics of the stack-gas emissions, which would have to be addressed. Appendix D-3 lists the oil products used in the overall production of electricity from gas turbines in the New York City area. Peak demand for electricity is higher in the summer than in the winter, and in summer, gas supplies are abundant. Therefore gas supplies are unlikely to affect reliability calculations as discussed in Chapter 5, which focus on the summer peak, but they could well become a constraint during the winter peak. In addition, the increased use of backup oil in the winter raises energy security and environmental issues. The availability of natural gas in the general area of the Indian Point facility is a key parameter in evaluating alternative generation technologies to replace the two nuclear units. The Algonquin Pipeline system crosses the Hudson River close to the Indian Point power plant on the way to Connecticut. Algonquin’s two pipes have a combined capacity of 1.15 billion cubic feet per day (bcf/d), providing natural gas from the Gulf of Mexico into New York and on to New England. New York diverts some 0.12 bcf/d of the gas before it reaches Connecticut. A possibility exists that some of New York’s share could be combined with one or more other supplies to assist in generating about 800 MW. The current and future gas supplies would be considered interruptible, since the market environment does not compensate generators for the extra reliability from firm gas supplies or backup fuel supplies. In addition, a new gas pipeline, the Millennium Pipeline, is currently being installed in New York State. Phase 1 of the project is expected to be complete by November 2006. The line comes from central New York and crosses the Algonquin system near the Ramapo Substation in Rockland County. This line also might supply enough gas for an additional 1,000 MW beyond commitments to customers. The Lovett Power Station site could be served by either line. The
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs TABLE 3-2 Potential Generating Technologies Considered by the Committee for Replacing Indian Point Type of Plant Assumed Capacity (MW) Relative Potential by 2015a Electricity Cost (¢/kWh)b Output at Peak Demandc Additional Considerationsd Natural gas Conventional gas combined cycle 250 Large 4.4 High F, C Advanced gas combined cycle 400 Large 4.1 High F, C Advanced combined cycle with carbon sequestration 400 Small 6.4 High F, R, D Conventional combustion turbine (simple cycle) 160 Large 5.8 High F, C Advanced combustion turbine (simple cycle) 230 Large 5.3 High F, C Coal Pulverized coal 600 Large 3.7 High T, CC Pulverized coal supercritical 500 Large 3.8 High T, CC Integrated coal gasification combined cycle (IGCC) 550 Large 3.7 High T, D, CC IGCC with carbon sequestration 380 Small 6.0 High T, R, D Fluidized-bed coal 500 Large 4.7 High T, CC Renewable energy Biomass 80 Small 7.2 High Municipal solid waste landfill gas 30 Small 3.5 High P Wind Large 100 Moderate 5.7 Low P Medium 50 Small 6.0 Low P Small 10 Small 9.9 Low Solar photovoltaics 5 Smalle 25.0 Moderate Solar thermal 100 Small 30.0 Moderate Advanced nuclear 1,000 Small 4.2 High T, P a“Large”: the total contribution could be more than 500 MW. “Small”: the total is likely to be less than 100 MW. Rated on the basis of readiness of technology, fuel availability, siting difficulties, permitting time, and other factors. bCosts are from Appendix D-1 and are representative for the nation, not the region, which is higher. c“High”: virtually all of the maximum capacity can be expected to be available during peak demand. “Moderate”: at least half the maximum capacity is likely to be available during peak demand. “Low”: it cannot be counted on. dF: additional fuel supply needed; R: research needed; D: demonstration needed; T: additional transmission needed; P: public acceptance questions; CC: high carbon dioxide emissions (>1 lb CO2/kWh); C: moderate CO2 emissions (<1 lb CO2/kWh); no C means little or no CO2 emissions. ePV may make a significant contribution as a demand-reduction technology, as discussed in Chapter 2. SOURCE: See Appendix D-1. three coal-fired units (totaling 431 MW) at the site—on the west side of the Hudson River just across from and south of the Indian Point site—are scheduled to be shut down by 2008, so that site might be available for new gas-fired tur-bines. Thus, there is likely to be enough gas to supply a significant amount of new capacity at Lovett Station or elsewhere in the area. In addition, other pipelines have been proposed, as shown in Appendix D-4, “Proposed Pipeline Projects in the Northeast.” However, two other factors must be considered: namely, the price of gas and other growing demands for the gas (also discussed in Chapter 5). Current prices for natural gas have been high since the two hurricanes in 2005 damaged some of the infrastructure in the Gulf of Mexico (DOE/EIA, 2005). Also, the overall supply to the state does not appear likely to be increased after the Millennium Pipeline is completed, for the foreseeable future. If so, the New York City area may not be able to continue increasing its use of natural gas for the near term. Furthermore, the longer-term gas supply picture is not encouraging unless resources such as liquefied natural gas (LNG) imports are increased, and LNG imports are uncer tain with respect to timing, volumes, and locations for terminal facilities. Investors will have little incentive to build greater pipeline capacity should the supply return only to pre-storm levels in the Gulf region. Data suggest that gas production from western Canada is declining. Diversions to other users may further limit deliveries to New York. Gas production levels in eastern Canada have experienced poor performance to date, although some gas may become available from Canadian Grand Banks fields. Overall, imports from Canada are not likely to increase significantly unless LNG is routed through Canada. It should be noted that natural gas exploration has increased in the areas south of the Finger Lakes in New York State, and gas production is at record levels for that area (40 bcf per year, or enough for about 800 MW of power generation). Although it seems as if sufficient gas might be available to replace Indian Point generating capacity, in fact all of the excess may well be committed some time before the plants are shut down. Electricity demand is growing in the New York City area, and several other plants are scheduled to be retired and must be replaced. All new generating capacity
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs currently being built in New York State, over 2,000 MW, is gas-fired. As discussed in Chapter 5, as much as 1,600 MW could be needed by 2010 to meet reliability requirements even without closing Indian Point. Almost all of the generating capacity in the planning stage that could be brought online by 2010 also is gas-fired (883 out of a total of 1,033 MW). Advanced natural-gas combined-cycle turbine generation facilities can provide reliable and environmentally attractive electric production service to the New York City region, but the production costs are essentially driven by the price and availability of the natural gas obtained from distant sources. At current prices, fuel costs alone are about 4 cents per kilowatt-hour (¢/kWh) in combined-cycle plants and 6 ¢/kWh in simple-cycle plants. In comparison, coal and nuclear plants have fuel costs of only 1 to 2 ¢/kWh, although their operating and capital costs are higher than for gas-fired plants.2 Table 3-2 shows estimates of the total costs of electricity for all the options considered by the committee. The breakdown by fuel operations and capital are in Appendix D-1, “Cost Estimates for Electric Generation Technologies.” One possibility would be to replace older, simple-cycle gas turbines with modern combined-cycle plants. This switch, called repowering, can result in 50 percent more power from the same supply of natural gas. In New York City, the East River plant is being repowered, and two units at Astoria are expected to be repowered. Other plants could also be considered. Coal Coal-based power production provides approximately 14 percent of the electric energy used in New York State, versus some 50 percent for the nation as a whole. No coal-pow-ered facilities are located in Zones H, I, J, or K, but there are two small coal-fired units (at Lovett Station) in Zone G. The major coal-based electric generating facilities are located in western sections of New York State. The amount of coal-based electricity produced in the state decreased by 1 percent between 2004 and 2005. The closing of the Lovett Station coal-burning generators will reduce this even more. Coal plants require larger sites than do natural gas plants, in order to accommodate the storage of a 30-day supply of coal, associated ash-management systems, and defined areas to accommodate storm-water-management programs. Coal plants, therefore, are located in areas where property values are relatively low. Land values in the Lower Hudson Valley and New York City areas are among the highest in the nation. Environmental considerations such as stack-gas emis sions, noise from unit trains bringing coal and removing ash, and cooling water requirements all contribute to major siting challenges when using any coal-based generation technology in major urban areas. Coal-based technologies that were considered and evaluated with respect to operating costs are discussed in Appendix D-5, “Coal Technologies.” Coal-based power plant technologies that could produce power for the New York City region would be located at some distance from the region, requiring long transmission lines. Therefore, the cost of the power would include transmission costs as well as production costs. In addition, some air quality issues could arise, depending on the location of the associated site. Coal plants also emit more carbon dioxide per kilowatt-hour produced. Technologies are being developed to capture and sequester the carbon dioxide, but that process will add significantly to the cost of the electricity. Appendix D-5 discusses the technology (integrated gasification, combined cycle—IGCC—that will be most appropriate for capture of carbon dioxide). A new coal plant built upstate from the New York City area might be the lowest-cost replacement for Indian Point, even with a new transmission line. Thus it should be included in the list of options. However, the committee believes that it is unlikely for a coal facility to be permitted and constructed even in upstate New York by 2015, especially considering the uncertainties over carbon dioxide. Biomass Biomass represents a renewable fuel source for power generation. In the New York City area, biomass consists of municipal solid waste, sewage sludge, wood waste, agricultural waste, and other residues. Today there are five waste-to-energy plants in the downstate area, with one in Zone H and four in the Zone K area. The total capacity for these five units is 166 MW, and collectively they produced 1,274 gigawatt-hours (GWh) of power in 2004 of the 52,000 GWh generated in Zones H, I, J, and K. Methane derived from biomass sources can be burned in gas turbines, and biomass in a solid form can be burned directly or gasified. It also can be co-fired in coal-based plants, but as noted above, coal plants are unlikely to be sited in the zones of interest for a variety of reasons. In the 1980s, there was a move to have a waste energy facility located in each of the five counties of New York City as a measure to assist the city in managing its wastes and to address the need for fuel diversification in the city. The plan was dropped by the New York City government primarily because of strong and widespread public opposition to waste-to-energy plants being located in the city. The principal concerns were air quality and health issues. Municipal solid waste and sewage sludge currently produced in the city are shipped out of state, even though today’s technologies are cleaner and might engender less public resistance. 2 Locational-based marginal prices for the NYISO-run wholesale power market are given at https://www.nyiso.com/public/market_data/pricing _data.jsp. Accessed March 2006. As an example, the 4:00 p.m. wholesale clearing price of electricity on January 23, 2006, was 11.9 ¢/kWh in New York City.
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs Biomass appears unlikely to be a significant new source of electricity for the New York City region. Additional information on the potential of the biomass resources is contained in Appendix D-6, “Generation Technologies—Wind and Biomass.” Wind Wind energy systems have entered the New York State market with some 100 MW of capacity installed by 2005, and more is expected. The wind facilities are located in the central and northern areas of the state. The New York State Energy Research and Development Authority (NYSERDA) has initiated a wind development program that is installing some 500 MW of new wind capacity as a component of the State’s Renewable Portfolio Standard development program. This program mainly provides support to developers after the units are placed into service. The developer has the responsibility to site, license, construct, and place into service its wind facility. New York State has several excellent wind sites that are being evaluated by developers for near-term application. At this point, few land-based sites are located close to the In-dian Point facility that have the desired wind characteristics and available land to install wind turbines that could contribute to the replacement of the generation from the Indian Point plants. A project has been proposed at a site in the ocean off the south shore of Long Island. This project is proceeding, but at a pace slower than originally anticipated, owing to rising costs. Experience with offshore wind projects is limited, and the developers are monitoring projects located elsewhere in the world. The Long Island project and other offshore sites have the resource potential for considerable generation of electric power, but no units have been installed there, and considerable opposition can be anticipated, as has occurred in Massachusetts. Technically there is sufficient wind resource in New York State to replace the Indian Point units, but resolving site location and permitting issues is key to successfully placing units into service. The greatest challenge for using wind to replace large baseload electric generation units is the intermittent nature of the resource. The availability factor for wind is 30 to 40 percent, compared with about 90 percent for nuclear and coal plants, and the resource is available only when the wind is blowing, not when demand is high. Storage will smooth out the intermittent nature of the resource, but that technology is not yet readily available. The issues associated with expanding the use of wind in the state are discussed in Appendix D-6. Solar Solar energy can be used to generate electricity either through the use of solar photovoltaic (PV) systems or through solar thermal power generation technologies. Solar PV electricity is increasingly being used for many applications around the world. PV use has increased as the price of solar cells and the resultant power costs have decreased and the reliability of the products has risen to a level that is acceptable to consumers for some applications. PV applications are limited by the dependence on the availability of sunlight, but for some applications either that does not matter or else a small amount of battery storage can suffice. The technology promises to grow substantially in the distributed-generation-systems market, as discussed in Chapter 2. PV would require large land areas to collect sufficient energy to contribute to the bulk power markets and is unlikely to be a factor in New York State by 2015, but rooftop-mounted systems supplying directly to the retail market could become significant. Solar thermal generation involves the use of mirror-like collectors designed to focus sunlight onto metal surfaces, which in turn through various systems can produce a steam product. The steam is then used in a steam turbine to produce electricity. One advantage of the solar thermal concept is that the energy of the Sun can be stored in a liquid material on a clear day and then later extracted to produce steam at night or on cloudy days. Solar thermal generation requires large land areas to house the collectors and very direct sunlight to be economically attractive. The earliest applications of solar thermal technologies will be in the deserts of the southwestern part of the United States. The specific characteristics of the PV technology are discussed in Appendix D-7, “Distributed Photovoltaics to Offset Demand for Electricity.” Advanced Nuclear Several advanced nuclear technologies are being explored for possible application in the 2015-2020 time frame (EPRI, 2005). The concepts are being supported through programs initiated in part by the recently enacted federal Energy Policy Act of 2005. The Nuclear Regulatory Commission has certified three designs, which could be started shortly after an appropriate site is found and certified. Several consortia of energy companies (including Entergy Corporation) are moving forward on various plans. A site at Oswego, New York, on Lake Ontario, had been considered but is not part of any current plan. That site had strong local support and may be considered in future plans. Nuclear power could provide New York State with an electric power option that has no carbon dioxide emissions (which contribute to global warming), and no contribution to acid rain or mercury contamination. However, the committee concluded that a new nuclear plant in New York State is unlikely before 2015. One or two of the projects now being planned in other states might be completed by 2015, but most companies are likely to wait in order to see how these plans progress before starting more projects.
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs Overall Considerations A variety of supply options could contribute to replacing one or both reactors at the Indian Point Energy Center. As suggested in the previous discussion and in Table 3-2, the committee concludes that advanced natural-gas-fired combined-cycle plants are the generation option capable of making the biggest contribution at the lowest cost by 2015. This position assumes the ability to site such facilities in the Lower Hudson Valley/New York City area, favorable economic and regulatory conditions for investors, sufficient advance notice that the power will be needed, and a long-term fuel supply. One option that could be considered in the near term is to locate some 2,400 MW of natural-gas-fired combined-cycle plants at the current Lovett Station site, described earlier in this chapter. The site is currently being used for electric production. However, the current operator is just emerging from bankruptcy and may not be in a position to develop any new facilities. If that issue can be resolved, the site could be developed for natural-gas- and/or oil-fired generation. The site has a transmission corridor, with limited transmission currently installed, a developed waterfront, and basic elements of infrastructure. However, environmental impacts would need to be addressed, as would fuel delivery. The greatest challenge would be to secure sufficient natural gas supplies to satisfy the projected production levels, including very high capacity factors. Two large natural gas lines are located near the Lovett Station site, and more natural gas might be added to the two existing systems from gas wells located in the state. If new sources of gas and new pipelines are required, the issues of gas availability and price must be examined in much greater detail than that allowed by the committee’s resources. Coal-based technologies potentially offer attractive production costs, but the physical requirements of a large plant site in the region of the Indian Point Energy Center, combined with air quality issues, new rail lines to bring in the coal, and related technical challenges limit potential opportunities for investors to promote this fuel source for application in the greater New York City area. If natural gas prices remain high, a coal plant upstate with a new transmission line to the New York City area might be a cost-effective solution. Both natural gas and coal plants emit carbon dioxide (coal plants emit about twice as much per kilowatt-hour as natural gas plants), which nuclear plants do not. New York is part of the Regional Greenhouse Gas Initiative (RGGI), which proposes to limit emissions of carbon dioxide and other greenhouse gases. Achieving RGGI goals will be more difficult if Indian Point is replaced, as discussed in Chapter 4. New York State is supporting renewable energy development for power production, including a recently adopted Renewable Portfolio Standard. Nevertheless, renewables are unlikely to provide the Lower Hudson Valley/New York City area with a significant share of the power provided by Indian Point within the time frame of this study. ELECTRICAL TRANSMISSION Existing Transmission Most Americans are generally unaware of the vast electrical transmission network that connects a myriad of power-generating stations to the local power lines servicing their homes and businesses. Electricity is typically generated in large central power stations at 13,800 volts (13.8 kV) then often “stepped up” to 345 kV through power transformers and associated equipment in order to transmit the power efficiently over long distances. These high-voltage transmission lines provide the backbone for the bulk electrical power system throughout the United States. Transmission lines, however, can be designed to be operated at voltages other than 345 kV. Other typical voltages for transmission lines in the United States include 765 kV, 500 kV, 230 kV, 138 kV, 115 kV, and 69 kV. Power system engineers select the optimal voltage for a particular transmission line based on a number of design considerations, including the line’s proximity to generation and customer load. In general, however, transmission lines with higher voltages are utilized to interconnect generating plants to the bulk power system. The bulk power system in New York State is similar to that in many other regions throughout the United States and Canada. According to NYISO, the bulk power system in New York State, the New York Control Area, contains more than 10,000 miles of transmission lines with voltages equal to 115 kV and more. Figure 1-1 in Chapter 1 shows the major transmission facilities in the NYCA with voltages of 230 kV and greater. The NYCA is electrically connected to neighboring control areas in the northeastern United States and the Canadian provinces of Quebec and Ontario through special high-volt-age transmission lines, often referred to as “ties” or “inter-faces,” such as those shown in Figure 1-1. The total nominal transfer capability between the control areas in the Northeast is less than 5 percent of the total peak load of the region and is declining as a percentage of such load (NYISO, 2005b). This minimal import and export capability over the ties among the Northeast regional control areas means that the NYCA power system places even greater reliance on the internal generation resources located within a particular control region. Transmission constraints or “bottlenecks” are not just associated with the constrained ties between New York and its neighboring control areas, however. The NYCA has several major transmission bottlenecks within New York State, which significantly affect the free flow of power on its bulk transmission system. In particular, the electrical transmission system around southeastern New York State, including greater metropolitan New York City and Long Island, is se
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs verely constrained owing to a lack of adequate transmission capacity into this area. As a result of the limited transfer capability into southeastern New York State, this subregion must place greater reliance on the generating plants located within greater metropolitan New York City and Long Island. As shown in Chapter 5, a new transmission line could deliver a large fraction of the power provided by Indian Point. Table 3-3 and Figure 1-1 further describe the approximate location of the three major transmission constraints within the NYCA. The Total East Interface constrains power flowing from western New York State, PJM, and Canada into eastern New York State. The Central East Interface is located east of the Total East Interface and serves to further constrain power flowing from the west and central portions of the NYCA. Finally, the Upstate New York-Southeast New York (UPNY-SENY) Interface severely constrains power flowing into southeastern New York State from the rest of New York and from PJM and Canada. NYISO has segmented the NYCA into 11 distinct zones, as explained in Chapter 1, to accommodate the location of the transmission interfaces and to respect the service territories of the transmission owners. These NYCA zones (see Figure 1-3 in Chapter 1 of this report) function as separate pricing zones under the locational-based marginal pricing (LBMP) wholesale power market operated by NYISO. Given the limited transfer capability shown in Table 3-3 at the transmission interfaces, and the supply-and-demand balance for electricity, the southeastern New York zones (Zones H, I, J, and K) experience the highest average and peak prices within the NYCA. Table 1-1 in Chapter 1 shows the approximate consumer load and associated generating capacity in each NYCA zone. Generating plants in southeastern New York are particularly valuable because they are on the high-demand side of the constraints. The Indian Point generating plant is located in the premium southeastern New York Zone H; hence the consumers in Zones H, I, and J heavily rely on it to meet demand. It is therefore very important to take the bulk transmission system into account when the retirement of Indian Point Units 2 or 3 is considered. TABLE 3-3 Nominal Transfer Capability Between New York Regions Transmission Interface Transfer Capability (MW) Total East 6,100 Central East 2,850 Upstate New York-Southeast New York 5,100 Cable New York City 4,700 Long Island 1,270 SOURCE: New York Independent System Operator. New Transmission New transmission capacity, if designed to adequately increase the transfer capabilities among the Total East, Central East, and UPNY-SENY Interfaces, may provide a partial solution to the retirement of Indian Point, including system reliability benefits. Such new transmission capacity would likely come in the form of either an expansion of the existing high-voltage alternating current (HVAC) transmission systems or the addition of new high-voltage direct current (HVDC) transmission facilities. New AC transmission facilities may include the replacement of conductors on existing transmission facility structures or the installation of new transmission facilities including new tower structures and related components. Such new AC transmission facilities may also require additional right-of-way land resources and potential system outages during construction periods. An expansion of the existing AC transmission system would likely serve to increase system reliability and decrease the marginal cost of electricity in southeastern New York. New AC transmission facilities may also be coupled with dedicated generation resources to further support New York’s “in-city” generation requirements. An illustrative example of such a new AC transmission facility would be the proposed 550-MW Public Service Electric & Gas (PSEG) Cross Hudson Project. That project includes the interconnection of an existing 550 MW natural-gas-fired combined-cycle generating unit located at a New Jersey-based utility, PSEG’s Bergen generating plant, with the Consolidated Edison substation at West 49th Street in New York City via underground 345 kV transmission conductors and associated facilities. Combinations of dedicated power-generating resources and interconnection facilities such as the PSEG Cross Hudson Project may offer additional alternatives to adding new generation resources directly into transmission-constrained zones such as Zones H, I, J, and K. However, as useful as this project could be, it is currently inactive and may not be revived. HVDC transmission projects may also provide partial solutions to the loss of Indian Point Units 2 and/or 3. Such HVDC transmission projects typically require the installation of an AC/DC converter station, HVDC conductors, and a DC/AC converter station. The process entails the conversion of alternating current to direct current (in the AC/DC converter station located near a sending substation), transmission of the power (typically long distances) through high-voltage direct current conductors, and finally the conversion of direct current to alternating current (in the DC/AC converter station) adjacent to the receiving substation. Because an HVDC line is isolated from the regular HVAC grid, it is not subject to the same reliability issues, and the power that it delivers is considered to be equivalent in reliability to that from a plant within the zone of the end point. In particular, New York City and Long Island (Zones J and K), which
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs have requirements for locally produced power (80 and 98 percent, respectively), obtain the same reliability benefit from a dedicated HVDC line as they would from a local power plant. The Neptune transmission line from New Jer-sey to Long Island will provide reliability benefits as well as cheaper power when it commences operation in 2007. The addition of a new 1,000 MW HVDC transmission facility between Marcy and Rock Tavern Substations could serve as a suitable alternative to the compensatory action of adding 800 MW of new generation in Zone J. This alternative also serves to increase New York’s statewide electric system reliability and could lower total system production costs within the greater Northeast region, including New York State. Further, an additional benefit may include a reduction in imports of electricity from outside the Northeast region owing to the more efficient use of indigenous generation located in upstate New York and PJM (Hinkle et al., 2005). In summary, it is clear that new transmission projects can play an important role in the ultimate energy and capacity solution relating to the potential loss of power from the In-dian Point units. It is likely that a combination of modifications to the existing AC transmission system and the installation of new HVDC transmission projects will provide the best complement to the addition of new generating resources and efficiency programs to solve New York’s future electricity needs. RELIABILITY AND REACTIVE POWER Reliability Most of the power interruptions of the typical customer are brief, affecting only a small area, although even very short interruptions that disturb computers and voltage variations that affect voltage-sensitive equipment can be damaging. Many power interruptions are due to local problems, such as an automobile accident knocking down a power distribution pole or a squirrel getting inside a vulnerable piece of equipment in a substation. Outages in distribution systems are outside the scope of this report, which is concerned with the bulk power system. When the transmission system goes down, perhaps due to severe weather, earthquakes, or multiple equipment failures, entire regions can be blacked out, and recovery can be lengthy. Very large multistate disturbances such as that experienced in August 2003 are rare and involve a combination of many unlikely events. Reliability is measured by the frequency, duration, and magnitude of interruptions and other adverse effects on the electric supply. The regional reliability councils formed after the 1965 Northeast blackout (New York is in the Northeast Power Coordinating Council) have tried to quantify these disturbances by requiring a measure of reliability based on computing the likelihood that the demand for power cannot be met. Load is modeled as a demand for power that is weather-dependent and varies with the season, the day of the week, and even the hour of the day. The maximum load tends to occur on the hottest summer days. Statistical descriptions of the historical availability of each generator are used to compute the expected number of days in a 10-year period when the load could not be supplied (the loss-of-load expectation, or LOLE). The New York State Reliability Council requires that the number be less than 1 day in 10 years. Changes in the system that would increase the LOLE to more than 1 day in 10 years would not be acceptable. It is unusual for a blackout to occur simply because a large number of generators were unexpectedly out of service (the 1965, 1977, and 2003 blackouts were much more complicated). Nevertheless, the LOLE is useful in determining how much extra generation a given area requires. Meeting this standard in the NYCA usually means that the available capacity (the total power of all generators able to be scheduled to serve the load) should exceed the peak load by 18 percent. Because power can be imported from neighboring areas, the reliability and capacity of both the transmission system and the generation equipment must be included in the analysis. The loss of transmission lines to other areas (notably New England, PJM, or Canada) could have serious consequences on a hot summer day. Relief from other control areas is limited, however, as interarea transmission capacity is about 5 percent of peak load and is decreasing with time. A reliable power system has enough excess installed generating capacity so that the load can be supplied even if some generators are out of service for maintenance or because of unexpected problems, and it has a transmission system that is adequate to transport the power from wherever it is generated (inside or outside the control area) to the customers. The mix of generation normally includes some inexpensive baseload generators that tend to run at a constant output around the clock and serve the minimum (base) load, along with units that respond more rapidly to changes in demand and can follow the peak. Nuclear units are operated as baseload units because they usually have the lowest variable operating costs. An additional reliability concern is the supply of fuel for generators. The adequacy and diversity of fuel constitute an important issue in operating the system and planning new generation. Heavy reliance on a single fuel source or a single pipeline for natural gas could have serious consequences if this supply were interrupted. The competing demand for natural gas for heating in the winter must also be considered as most gas-fired power plants in New York operate on in-terruptible gas-supply contracts, and therefore most are dual-fuel units that can be switched to oil firing. On an annual basis, however, as noted in Chapter 2, dual-fuel units in New York use natural gas for about 82 percent of their annual generation.
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Alternatives to the Indian Point Energy Center for Meeting New York Electric Power Needs Reactive Power Major power system disturbances have, in one way or another, involved unstable oscillations of electrical quanti ties. Dynamic changes in power flows, or in system frequency (departures from 60 hertz), or in voltage reduction are all signs of system instability. Frequency excursions take place when the balance between supply and demand for power is upset. Too much demand produces a lower frequency, and too much supply results in a higher frequency. As the power system came apart in August 2003, there were islands with excess generation and islands with too little generation. There is another kind of power in alternating current systems, associated with the magnetic fields produced by currents flowing in transmission lines, generators, and motors. This power is called reactive power and is measured in vars (for volt-ampere reactive).3 Reactive power represents energy stored in the magnetic field and later released. Motors such as those in air conditioners and refrigerators also require reactive power to function correctly. Reactive power also is essential for the smooth operation of the transmission grid. It helps hold the voltage to desired levels. Inadequate reactive power leads to a decrease in the voltage of the system in which the shortage exists. For an interconnected system where active power is exactly in balance, the frequency is constant and the same everywhere, and the system is said to be in synchronous operation. Voltage, however, varies from location to location, depending largely on the reactive power balance. If a given load has a large reactive demand, the voltage will be lower at that point than at others. Low voltage can damage equipment and, if low enough, can cause system instability and a voltage collapse. There have been a few voltage collapses solely because of a shortage of reactive power. It is more common that reactive power problems aggravate active power problems in large power system disturbances, as was the case in the August 2003 event (U.S.-Canada Power System Outage Task Force, 2004). Active power can be transmitted over great distances, while reactive power problems must be solved locally. Generators themselves are an excellent source of reactive power but at some cost. Increasing the reactive output of a generator results in a decrease in the possible active power output and, if not specifically compensated, a loss of income received for real power output. Capacitors can be a second source of reactive power by storing energy in electrostatic fields rather than electromagnetic fields. Capacitors can be fixed or variable in size. Distributed generators—for example, microturbines and synchronous motors—can also supply reactive power, but these units are outside the control of the system operator and cannot necessarily be counted on when needed. Indian Point is a large supplier of reactive power to the grid in southeastern New York State, capable of providing about 1,000 megavars of reactive power. If it is shut down, that reactive power must be replaced. Insofar as replacement generation is located upstate or even farther away, it becomes even more important to ensure adequate supplies of reactive power. That could be done by installing capacitors at the Indian Point site or in the general area. Generating vars is not expensive, but it is a critical necessity that must be planned for if Indian Point is to be closed. NYISO projects that, even with Indian Point operating, voltage constraints due to reactive power deficiencies in the Lower Hudson Valley will lower system reliability to unacceptable levels. Consequently, NYISO has solicited market-based and regulated backstop solutions to correct the reliability deficiency.4 REFERENCES DOE/EIA (Department of Energy/Energy Information Administration). 2005. “Natural Gas Weekly Update.” December 22. Available at http:/ /tonto.eia.doe.gov/oog/info/ngw/ngupdate.asp. Accessed December 22, 2005. EPRI (Electric Power Research Institute). 2005. “Making Billion Dollar Advanced Generation Investments in an Emissions-Limited World.” Background paper for the EPRI Summer Seminar, August 8-9, 2005, San Diego, Calif. Hinkle, G., G. Jordan, and M. Sanford. 2005. “An Assessment of Alternatives to Indian Point for Meeting Energy Needs.” Unpublished report for the National Research Council, GE-Energy, Schenectady, N.Y., December 19. NYISO (New York Independent System Operator). 2005a. Comprehensive Reliability Planning Process. October 25. —. 2005b. Comprehensive Reliability Planning Process (CRPP), Reliability Needs Assessment, and NYISO Comprehensive Reliability Planning Process, Supporting Document and Appendices for the Draft Reliability Needs Assessment. December 21. U.S.-Canada Power System Outage Task Force. 2004. Final Report on the August 14, 2003 Blackout in the United States and Canada. April. Available at https://reports.energy.gov. Accessed March 2006. 3 Active power, the familiar type of power that keeps lightbulbs burning, is measured in watts. Consumers pay for active power (1,000 watts used for an hour is a kilowatt-hour) but usually not for reactive power. 4 See M. Calimano, NYISO solicitation letter to S.V. Lant, R.M. Kessel, E.R. McGrath, and J. McMahon, December 22, 2005.
Representative terms from entire chapter: