On November 17, 2016, FERC issued a Notice of Proposed Rulemaking (“NOPR”) in which it proposed modifications to its pro forma interconnection agreements that would require new generating facilities to install and enable primary frequency response equipment as a condition of interconnection. FERC explained that the proposed modifications are intended to address industry-wide reliability concerns related to declining frequency response performance.
In the NOPR, FERC explained that changes in the balance between growth and load cause frequency to deviate from its scheduled value of 60 Hertz. FERC stated further that deviations too far above or below 60 Hertz can threaten reliability by causing generation tripping, under frequency load shedding, or cascading outages. According to FERC, primary frequency response provided by individual generators can mitigate abnormal frequency variations through the autonomous actions of a generator’s turbine governor, and other plant level control systems. However, as noted by FERC, there is no requirement that all generators must install primary frequency response equipment. Moreover, generators that have installed such equipment can decide at the plant level whether – and to what extent – they will enable it during a frequency disturbance.
To address some of these issues, FERC proposed to amend its pro forma Large Generator Interconnection Agreement and pro forma Small Generator Interconnection Agreement to include the following: (1) requirements for new generating facilities to install, maintain, and operate equipment capable of providing primary frequency response as a condition of interconnection; (2) requirements for governor or equivalent controls to be operated, at a minimum, within maximum 5 percent droop and ±0.036 Hz deadband settings; (3) requirements to ensure the timely and sustained response to frequency deviations, including provisions to prevent plant-level (i.e., outer-loop) control equipment from inhibiting primary frequency response and resulting in premature withdrawal; and (4) a requirement for droop parameters to be based on nameplate capability with a linear operating range of 59 to 61 Hz. FERC also proposed to prohibit generating facilities from inhibiting primary frequency response capability.
In the NOPR, FERC did not, however, propose a generic “headroom” requirement that would require generating facilities to operate at less than their maximum output in order to ensure sufficient ability to increase output in response to under-frequency conditions. Similarly, FERC did not address primary frequency response service compensation.
FERC’s NOPR seeks comment on whether its proposals are sufficient to ensure adequate primary frequency response to ensure system reliability. Additionally, FERC seeks comment on its proposal to not impose a generic headroom requirement.
Also on November 17, 2016, FERC issued a separate NOPR in which it proposed to amend its regulations to require each Regional Transmission Organization and Independent System Operator to revise its tariff to remove barriers to the participation of electric storage resources and distributed energy resource aggregations in the capacity, energy, and ancillary service markets operated by Regional Transmission Organizations and Independent System Operators (see November 21, 2016 edition of the WER).
Comments are due within 60 days of publication of the NOPR in the Federal Register. A copy of the NOPR is available here.
by Christopher Nalls and Christopher Zentz