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Declaratory Ruling 19-14: Consolidated Edison Company of New York, Inc.

State of New York
Department of Environmental Conservation

In the Matter of the Petition of
Consolidated Edison Company of New York, Inc.
for a Declaratory Ruling


Consolidated Edison Company of New York, Inc. ("Con Edison") petitions, pursuant to Section 204 of the State Administrative Procedure Act and 6 NYCRR Part 619, for a declaratory ruling that the Department will automatically apply the emergency defense provisions of 6 NYCRR 201-1.5 and 6 NYCRR 201-6.6 (c) to in-City generators who violate NOx RACT emission limits under 6 NYCRR 227-2.4 and 6 NYCRR 227-2.5, or opacity requirements under 6 NYCRR 227-1.3, when responding to a Con Edison-declared emergency within its transmission district. The result of such a determination would be that in-City electric generators who supply power to the Con Edison transmission district in response to Con Edison's direction to go to maximum capability in the event of a power emergency in its transmission district, would not be subject to enforcement for violating these regulatory requirements.

Statement of Facts

For the purposes of this declaratory ruling only, the Department will assume that the facts alleged in the petition are true. The Department may take official notice of any fact not subject to reasonable dispute if it is either generally known or can be accurately and readily verified (6 NYCRR 619.2[b]). Hence, this declaratory ruling is based on the assumed facts provided by Con Edison and any other readily verifiable facts which are pertinent to this matter. The Department will engage in no fact-finding for the purposes of this declaratory ruling and the binding effect of the ruling is limited by the assumed fact predicate (see Power Auth. of State of N. Y. v New York State Dept. Envtl. Conservation, 58 NY2d 427, 434, 461 NYS2d 769, 772 [1983]). The Department will not assume the truth of statements which are legal conclusions.

Con Edison participates in the NYS Power System1 as a signatory to the Agreement Between New York Independent System Operator and Transmission Owners ("the NYISO/TO Agreement"). The purpose of that agreement is to assure that the New York Independent System Operator ("NYISO") can fulfill its mission, as set forth in the Independent System Operator Agreement ("the ISO Agreement"), to maintain the safety, reliability and integrity of the NYS Power System (Exhibit 1, at 2-3).2 The terms of both the ISO Agreement and the NYISO/TO Agreement provide that the NYISO is to fulfill its stated mission by exercising day-to-day operational control over specified transmission facilities (Exhibit 1 to petition, Article 6.02; Exhibit 2 to petition, Articles 2.0, 3.0). The transmission owners continue to operate and maintain the transmission facilities, in accordance with the terms of the NYISO/TO Agreement (Exhibit 2 to petition, Article 2.0). They retain the right to take whatever actions they deem necessary to fulfill their obligations under local, state or Federal law (Exhibit 1 to petition, Article 17A.6; Exhibit 2 to petition, Article 3.10 [g]). The transmission owners have a legal obligation under both the terms of the NYISO/TO Agreement and Public Service Law § 65 to provide safe and reliable service to the public.

Con Edison is a regulated public utility and an investor-owned transmission owner, as that term is defined in the NYISO/TO Agreement (Exhibit 1 to petition, Article 1).3 In addition to participating through the NYISO in the NYS Power System4, Con Edison provides electric service to New York City and Westchester County through transmission and distribution facilities that are not a part of that system, and therefore not subject to the NYISO's day-to-day operational control. Part of Con Edison's transmission system is made up of 345 kV, 138 kV, and 69 kV underground feeder cables which supply the substations that serve the company's service area. The substations transform the power to lower voltages for use on the Company's distribution system. The underground feeder cables transfer power from upstate New York, neighboring states, and from generating plants that are within the company's distribution system. The company owns and maintains direct operational control over these feeder cables and its distribution facilities. In addition to its transmission facilities, Con Edison also owns electric generating facilities at its New York City steam stations, with an aggregate capacity of 630,000 kilowatts.

Directly at issue in this declaratory ruling are the responsibilities and authority of the NYISO and the transmission owners in the event of an emergency on the NYS Power System. To this end the NYISO/TO Agreement provides:

The Operating Committee of the ISO will promulgate procedures to provide for the assumption of authority by the Transmission Owners' control centers to respond to an Emergency. These procedures shall provide for the coordination of such response with the ISO. The procedures will provide that, in situations where immediate action is required, the Transmission Owners' control centers will have the authority to take actions, including without limitation, the following:

  1. exercising control over facilities listed in Appendix A-1 of this Agreement and generating units;
  2. starting quick start generation and the adjustment of generation;
  3. re-energizing transmission facilities following breaker trips;
  4. implementing emergency Load-Shedding and voltage reduction measures and subsequent restoration;
  5. voltage/VAR control during an Emergency;
  6. changing ratings of transmission facilities; and
  7. taking other measures consistent with Good Utility Practice that are required to respond to the Emergency.

Until the Operating Committee promulgates such procedures, the Transmission Owners will exercise the above responsibilities during an emergency.

The ISO's operating committee has not promulgated such emergency response procedures. Accordingly, Con Edison has its own emergency response measures which incorporate those set forth in the NYISO/TO Agreement.

In addition, Con Edison has developed emergency response measures to address its specific concerns that an emergency on the Con Edison system could produce feeder overloads or low voltage resulting in the burnout of one of Con Edison's feeder cables, which are located in underground pipes and conduits.5 Such a burnout requires the replacement of the entire cable, which can take up to several months. Under these circumstances the reliability of Con Edison's own operations, its equipment, or its ability to provide service to its customers could be affected.

When a feeder overload occurs, the Con Edison system operator orders remedial actions that correspond to the severity of the overload, to avoid burnout of the feeder cable.6 One of these remedial actions is load shedding, defined as "the systematic reduction of system demand by temporarily decreasing Load in response to a transmission system or area capacity shortage, system instability, or voltage control considerations under the ISO OATT" (Exhibit 1 to petition, Article 1.63). It is this last resort that Con Edison seeks to avoid through the relief sought in this petition. This would be accomplished through the addition of a step in its emergency procedures that would enable it to direct in-City electricity generators to go to maximum capability, without the concern that by doing so the generators might exceed their NOx RACT emission limits or opacity limits, and face enforcement by the Department.

Significantly, the remedial actions currently enumerated in Con Edison's System Operator's Emergency Procedure are almost always adequate to correct an overload condition without having to resort to shedding load. Overloads on the Con Edison feeders are so infrequent that Con Edison has had to shed load due to a feeder cable overload only once in the last 27 years. On that occasion full service was restored to the affected customer base after approximately 5 ½ hours.


It is solely its feeder cables that Con Edison is concerned with in this petition. Its request for relief is based on its concern that in a system emergency that produces unusually low frequency electric feeder overloads or low voltage, that overload condition may cause a feeder cable to burn out. If the cable must be replaced, the reliability of the company's service would be impaired for the duration of the time it takes to replace the cable, possibly for several months.

To alleviate this concern, Con Edison has requested that the Department issue a declaratory ruling similar to the one issued in response to an earlier petition by the NYISO (see DEC Declaratory Ruling #19-12). Con Edison seeks a Department determination that as part of its emergency response measures, Con Edison could call on generators who supply power to its transmission system to go to maximum generation, with the assurance that if in complying with such a request a generator exceeds any applicable NOx RACT or opacity regulations, the circumstances would automatically constitute an emergency, as that term is defined under 6 NYCRR 201-2.1(b)(12), that is subject to the affirmative defense regulation found at 6 NYCRR 201-1.5 and 6 NYCRR 201-6.6 (c).7 Such a response by in-City generators would presumably remove demand from the cable feeder portion of the Con Edison transmission system and obviate the potential need for Con Edison to shed load in response to the overload condition. Con Edison notes in its petition that the NYISO has no jurisdiction over its transmission lines/feeder cables and therefore no ability to offer the emergency excuse to the generators in the New York City and Westchester County service area, upon whom Con Edison would call to alleviate the burden on its feeder cables. In submitting this petition Con Edison is essentially equating its function in operating that portion of the Con Edison system that is not under the control of the NYISO, to that of the NYISO with respect to the NYS Power System. There are critical distinctions, however, that warrant denial of the relief that Con Edison seeks.

The declaratory ruling that Con Edison relies on in support of its request for relief in this petition granted the emergency defense to generators called on by the NYISO to go to maximum power generating capacity in response to a statewide power emergency (DEC Declaratory Ruling #19-12, at 11-12). This relief was granted based on the recognition that while the NYISO could rely on the legal duty of the transmission owners to provide service, the generators operate under free market principles, and have no obligation to offer power unless it is in their interest to do so. Since a direction to the generators by the NYISO to supply power in an emergency could result in legal liability on the part of the generators for the violation of environmental regulations, the Department granted the NYISO's request for an advance declaration that an emergency exists for those generators who comply with such a direction. The Department agreed to that relief for the specific purpose of preventing an imminent collapse of the NYS Power System. In DEC Declaratory Ruling #19-12 the Department specifically noted that the emergency would arise from the potential that a statewide blackout could occur in the event of an energy shortage in the NYS Power System, and was not caused by the particular operations of any one Generator who would potentially violate its NOx RACT emission limits and opacity requirements. Moreover, the relief requested by the NYISO was granted in express recognition of the fact that the NYISO has no direct control over power generation or the system that supports it.

Con Edison, by comparison, is a private, for-profit regulated public utility. It controls not only the distribution network in its transmission district, but it continues to own generating facilities in New York City. While Con Edison may function in the role of a system operator with respect to specified portions of its transmission system that are not part of the power network subject to the NYISO's jurisdiction, the fact remains that Con Edison is an investor-owned utility with direct control over its transmission facilities. Subject to proper regulatory approval Con Edison can build, buy, sell, merge, and otherwise transfer or convey its facilities. It can even terminate its relationship with the NYISO (Exhibit 2 to petition, Article 3.10 [c]). If it is required to expand or modify its facilities, it retains the right to recover all reasonably-incurred costs "plus a reasonable return on investment" (Exhibit 2 to petition, Article 3.10 [d]). In addition to its statutory duty to provide safe, reliable service to its customer base (Public Service Law § 65), Con Edison has a fiduciary duty to its investors to obtain a reasonable rate of return on the services it provides (Exhibit 2 to petition, at 1-2). Con Edison operates and maintains its transmission facilities, and derives revenue for doing so.

More importantly, the consequences of an overload condition on Con Edison's low-level transmission system do not compare to either the circumstances or the consequences of an energy shortage in the NYS Power System. While the possible burnout of a feeder cable may impact reliability in a portion of the Con Edison service area, there is no indication that Con Edison's entire transmission system, or even part of it, would definitively fail if a cable were to burn out in an overload condition. This simply does not warrant granting the type of broad relief that was granted to the NYISO to avoid the consequences of a statewide energy shortage. Con Edison has expressed valid concerns over the potential consequences to public health and welfare if a power failure were to occur. Nevertheless the fact remains that Con Edison exercises complete control over the system and facilities upon which it relies for the supply of electricity to its transmission district.


Con Edison has requested broad authority to guarantee that the Department will automatically apply the emergency defense provisions of 6 NYCRR 201-1.5 and 6 NYCRR 201-6.6 (c) to in-City generators who may be called upon to go to maximum generating capacity, in the event of an emergency that overloads the low-level feeder cable system portion of Con Edison's transmission district. The authority sought would be similar to that granted to the NYISO by the Department in DEC Declaratory Ruling #19-12. However, Con Edison's status as a for-profit utility that owns both generation and transmission facilities serving New York City and Westchester County differs significantly from that of the NYISO, which is an independent, not-for-profit corporation with no control over the system that supports the generation of power in this State. The NYISO exercises operational control over specified transmission facilities solely through a set of contractual agreements with transmission owners who have a legal duty of service to their customers. Moreover, Con Edison's concerns are limited to the possibility of a feeder cable burnout, in the unlikely event that an unusually low frequency electric feeder overload condition occurred in the system that would require correction through load shedding. This occurrence is a much different scenario than the possibility of a statewide blackout in the event of an energy shortage in the NYS Power System, for which the NYISO is responsible. Accordingly, for the reasons stated in this Declaratory Ruling, Con Edison's petition is denied.

Dated: July 07, 2005
Albany, New York

James H. Ferreira

Deputy Commissioner and General Counsel

1.Defined as "[a]ll facilities of the NYS Transmission System, and all those Generators located within the [New York Control Area (NYCA)] or outside the NYCA, some of which may be from time-to-time subject to operational control by the [Independent System Operator (ISO)]" (Exhibit 1 to petition, Article 1.86). The "NYS Transmission System" is defined as "[t]he entire New York State electric transmission system, which includes: (1) the Transmission Facilities Under ISO Operational Control; (2) the Transmission Facilities Requiring ISO Notification; and (3) all remaining transmission facilities within the NYCA" (Exhibit 1 to petition, Article 1.87).

2. As is fully explained in the declaratory ruling upon which Con Edison bases this petition (DEC Declaratory Ruling #19-12), when the NYISO was created it assumed the function of the former New York Power Pool, of which Con Edison was a member, without assuming any ownership or control over the electricity generation assets in the State. "The NYISO is an independent, not-for-profit corporation organized under New York law and created pursuant to the NYISO agreement" (DEC Declaratory Ruling #19-12, at 1). The NYISO does not generate electric power but manages the flow of power in the State by directing the operation of the NYS Power System to supply electricity to customers throughout the State. It must do this while maintaining the safety and reliability of the system through agreements with, among others, Transmission Owners like Con Edison (DEC Declaratory Ruling #19-12, at 1-3).

3. A transmission owner is defined under the Independent System Operator Agreement as "an entity that owns, controls and operates facilities in New York State used for the transmission of Energy in interstate commerce. A transmission owner must own, individually or jointly, at least 100 circuit miles of 115 kV or above in New York Sate and has [sic] become a signatory to the ISO/TO Agreement". (Exhibit 1 to petition, Article 1.130).

An investor-owned transmission owner is a transmission owner that is owned by private investors. At the present time these include: Central Hudson Gas & Electric Corporation, Consolidated Edison Company of New York, Inc., New York State Electric & Gas Corporation, Niagara Mohawk Power Corporation, Orange and Rockland Utilities, Inc., and Rochester Gas and Electric Corporation (Exhibit 1 to Petition, Article 1.50).

4. Con Edison owns overhead transmission lines operating at 500 kV, 345 kV, 230 kV, and 138 kV that are controlled and operated by the NYISO.

5. There are three categories of feeder overload conditions.

The first category occurs when the flow on the feeder exceeds the normal rating but is less than the long term emergency rating ("LTE") of the feeder. Con Edison has a three-hour period from the initial overload within which to take corrective action to reduce the flow on the feeder.

The second category occurs when the feeder exceeds the long term emergency rating but remains below its short term emergency rating ("STE"). Con Edison has 15 minutes from the initial overload within which to take corrective action to reduce the flow on the feeder.

The third category occurs when the flow exceeds the feeder's short term emergency rating. Corrective action is required immediately to bring the flow to within the short term emergency rating within five minutes of the initial overload, and the long term emergency rating within 10 minutes of the initial overload (Exhibit 3 to petition, section 6.1).

6. The system Con Edison currently has in place is as follows: whether the indicated condition is valid or due to a metering malfunction. as soon as possible with the NYISO Shift Supervisor that a Major Emergency has been declared on the Con Edison transmission system, stating the reason for the change in operating state. the condition is valid, initiate maximum generation. phase angle regulators to reduce transmission feeder loading. actions with the NYISO and neighboring Transmission Owners. the condition is due to the loss of transmission feeders, initiate rapid restoration as prescribed in System Operation Procedure SO5-4, Transmission Feeder Reclosure Procedure. prescheduled generation changes within the Con Edison control area that may aggravate the overload condition. if neighboring Transmission Owners can provide support to alleviate the emergency. the condition remains, determine if the overloaded transmission feeder may be removed from service. the transmission feeder cannot be removed from service or if the STE, LTE or normal rating violation still exists, implement 8% voltage reduction immediately to reduce the overload. the STE, LTE or normal rating violation still exists after executing all the viable steps listed above, and load shedding is the next step to be taken, request all generators who have not peaked to do so. the STE, LTE or normal rating violation still exists, initiate additional corrective action, including load shedding, that will reduce the transmission feeder loading below its overload rating in its corresponding time period. all of the above, for STE overloads, if the load has not been reduced to the LTE rating within 5 minutes, load shedding steps may be initiated immediately so that the loading will be reduced to the LTE rating within 10 minutes from the start of the overload condition.

(Exhibit 3 to petition, section 6.3).

Con Edison seeks to change the language in step 6.3.1-11 to the following:

If the STE, LTE or normal rating violation still exists after executing the preceding steps that were available, direct generators to go to maximum generation capability with the assurance that the DEC will not enforce noncompliance against generators who violate NOx compliance or opacity requirements temporarily as a result of following Con Edison's request.

7. This regulation provides, in relevant part, that "[a]n emergency constitutes an affirmative defense to an action brought for noncompliance with emission limitations or permit conditions for all facilities in New York State."

6 NYCRR 201-2.1 (b) (12) defines an emergency as "[a]ny situation arising from sudden and reasonably unforeseeable events beyond the control of the owner and/or operator of a facility, including acts of God, which situation requires immediate corrective action to restore normal operation and which causes the emission source to exceed a technology-based requirement under the permit or State-established emission limitations, due to unavoidable increases in emissions attributable to the situation. An emergency shall not include situations caused by improperly designed equipment, lack of preventive maintenance, careless or improper operation, or operator error."

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