Frigid Temperatures from Polar Vortex Drive Record Winter Demand

Peak Conditions Highlight Positive Grid Performance and Emerging Challenges

RENSSELAER, NY (01/09/2014)(readMedia)-- With extremely cold weather producing challenging electric system conditions across large parts of the country, the New York Independent System Operator (NYISO) successfully met a new winter record peak demand for electricity of 25,738 megawatts (MW) on Tuesday, January 7.

"Record-low temperatures in many portions of the nation resulted in a challenging day for electric system operators in New York, New England, the Mid-Atlantic and the Mid-West," said NYISO President and CEO Stephen G. Whitley. "However, thanks to excellent regional cooperation and coordination, the expertise of our operators and the performance of New York's generation owners, utilities and demand response partners, we successfully managed those challenges and maintained system reliability."

"That success was due in large part to the numerous initiatives we have undertaken with our stakeholders and neighboring regions over the past several years to enhance communications, operational coordination and regional, cross-border collaboration," said Whitley. "Conditions like those experienced on Tuesday also reaffirm the importance of efforts taking place at the Federal Energy Regulatory Commission, the New York State Public Service Commission, the NYISO and in other regions to enhance communication and coordination between the electric and natural gas industries."

Some of the successes and challenges from the record-breaking day included:

Inter-Regional Coordination: The NYISO and neighboring grid operators, including ISO New England, PJM, Hydro Quebec and the Ontario Independent Electric System Operator continue to work together on initiatives to improve coordination and communication. On Tuesday, the NYISO was able to import power from ISO New England and Ontario over the evening peak hours and export power to assist the PJM region.

Markets at Work: The NYISO's demand response programs, which reduce energy use at peak times, were activated to help support regional reliability and manage demand.

Wind Power: On Tuesday, the NYISO had the benefit of more than 1,000 MW of wind power throughout much of the day.

Challenges Highlighted: Extremely cold temperatures can cause equipment problems on the electric system, including reduced pressure in high voltage circuit breakers, icing in rivers for hydroelectric plants, frozen pipes and valves associated with outdoor auxiliary systems, and oil systems becoming more difficult to operate. While New York benefits from a diverse fuel mix for its generation fleet-including nuclear, natural gas, hydro, coal, wind and oil- natural gas fuels the largest percentage of the generation portfolio. In the winter, the millions of retail residential, commercial and industrial gas customers served by local utilities have priority on the pipeline system to meet heating and commercial needs. The high demand for natural gas during periods of extreme cold weather over a large portion of the country can reduce the availability of natural gas for generation plants. This differs from the summer when demand for natural gas by retail customers is relatively low and there is usually excess capacity on the pipeline infrastructure available for gas-fired generation facilities. These weather and system dynamics can make meeting a 25,738 MW record peak in the winter equally as challenging as meeting the record peak of 33,956 MW experienced last summer.

The January 7 record peak demand of 25,738 MW occurred between 6 p.m. and 7 p.m. The previous record winter peak demand of 25,541 MW was set on December 20, 2004.

Peak loads are measurements of the average total electric demand by consumers for a one-hour period. One megawatt of electricity is enough to power between 800 and 1,000 homes. Peak demand usually occurs in the late afternoon or early evening in winter and summer. During these periods, as throughout the year, the NYISO works with power producers and electric utilities to maintain reliable service to consumers.