Proper planning helped PJM Interconnection, ISO New England (ISO-NE) and the New York ISO (NYISO) maintain reliable operation of their respective region’s electric grids during the cold snap brought about by the polar vortex phenomenon during the week of Jan. 6, the RTOs told FERC.
In its response to FERC’s Jan. 8 data request regarding PJM’s operations during the cold weather events of Jan. 6-8, PJM noted that its responses are based on its preliminary review of the January events and, therefore, are subject to change pending the completion of its review of the situation.
FERC staff made the request in order to prepare a report on system operations during the weather events, a NYISO spokesperson told TransmissionHub on Jan. 14. That report will be provided by FERC staff to the commissioners at the Jan. 16 FERC meeting.
PJM and most of its neighboring balancing authorities experienced a polar vortex weather phenomenon that resulted in sub-zero temperatures and high-speed wind conditions from Jan. 6-8, and as a result, there was a significant increase in electricity demand in several transmission zones in the PJM region, PJM told FERC.
PJM added that while the cold weather negatively affected some generating plants and transmission facilities, with forecasting, prior planning, calling for load reductions by demand response resources and careful communications with its members and their gas suppliers, PJM was able to take steps to better manage the adverse effects of the weather conditions and ultimately keep the bulk electric system reliable and deliver power to customers.
During the January events, there was a significant increase in electricity demand in the PJM region, setting new records for the winter peak load. PJM added that the previous winter peak load record of 136,675 MW, set in February 2007, was broken on Jan. 7 when the load of 138,733 MW was reached. A new record was set later that same day when load reached 141,312 MW.
PJM also noted that it managed the weather effects by taking emergency actions, including its Jan. 3 request of FERC for expedited relief, for instance, to enable PJM to better communicate with certain natural gas pipelines operators serving PJM members to ensure reliability during the forecast extreme weather conditions.
Starting on Jan. 5, PJM declared a cold weather alert for Jan. 6-8, and on Jan. 6, PJM called for maximum emergency generation and a voltage reduction warning, leading to a call for public conservation for Jan. 7. PJM later extended the public appeal to Jan. 8 to better manage the continuing strain on primary reserves.
PJM noted that it held two joint calls with interstate pipelines in its footprint, one on Jan. 7 and another on Jan. 8. The pipelines, in general, had issued operational flow orders, restricting nominations to non-interruptible transportation customers. They also issued notices affirming the restriction of customers to their hourly schedules and the penalties that would apply if they went over their ratable amounts.
PJM also received reports of coal quality issues related to the heavy rains during the weekend before Jan. 6, and then subsequent icing of coal and coal-related equipment during the Jan. 6-9 period.
The RTO further noted that there were constraints on 345-kV and higher portions of its system during peak periods between Jan. 6 and Jan. 8, including the American Electric Power (NYSE:AEP) CIN Wheatland 345-kV tie line for the loss of the Jefferson-Rockport 765-kV line, and the PPL (NYSE:PPL) Susquehanna 21 500/230-kV transformer for the loss of Susquehanna Unit 1.
Also, 765-kV forced outages included AEP’s Kammer-Vassell-Maliszewski 765-kV line, while 765-kV planned/ongoing outages included AEP’s Baker Phase 3 765-kV reactor and Broadford 765-kV reactors.
PJM also noted that 500-kV forced outages included Dominion’s (NYSE:D) Mt Storm 500-kV G2T554 CB and PPL’s Juniata Keystone-Alburtis Tie 500-kV CB. The RTO said that 500-kV planned/ongoing outages included Baltimore Gas and Electric’s (BGE) Conastone 500/230-kV 500-3 transformer and Dominion’s Loudoun-Pleasant View 500-kV line.
Also, 345-kV forced outages included Commonwealth Edison’s (ComEd) 115-kV Bedford Park 345/138-kV TR82 transformer and 108 Lockport-120 Lombard 345-kV Line 10808. PJM added that 345-kV planned/ongoing outages included AEP’s Twinbranch 345/138-kV #6 transformer and Kanawha River 345-kV 1 & 2 series capacitors, as well as Duquesne’s Collier 345/138-kV T3 transformer.
Among other things, PJM said that lessons learned include that proactive communication with the states was helpful in notifying and clarifying emergency procedures and expectations. Also, cold weather preparations, such as seeking an operating agreement waiver from FERC for Order 787 further enabled gas/electric coordination, were helpful in securing additional data PJM needed to improve operations.
BGE and ComEd are subsidiaries of Exelon (NYSE:EXC).
ISO New England
ISO-NE also prepared a report in response to FERC’s request, but the report is not posted at this time, an ISO-NE spokesperson told TransmissionHub on Jan. 14.
“[T]he power system in New England performed as expected so we were in good shape through the latest cold snap,” the spokesperson said.
According to a summary of the ISO-NE report, the Jan. 15, 2004 “Cold Snap” had the lowest average temperature in the last 20 years and the all-time winter peak of 22,818 MW. The January 2014 days were among the coldest 5% of days in the last 20 years, with daily average temperatures between “5-12 degrees F.”
The summary further noted that while the preliminary peak load for Jan. 7 was 21,320 MW at 7.9 degrees Fahrenheit, the highest peak demand so far this winter occurred on Dec. 17, 2013, at 21,514 MW, although that figure is also preliminary.
Six natural gas-fired generators reported that they could not confirm whether they would be able to procure fuel when called intraday during the period from Jan. 7-8. Many of the resources that could not provide gas procurement answers in a timely way later called and advised they were available, the summary added, citing that as an indication of the difficulty in arranging for gas during tight pipeline conditions.
ISO-NE maintains daily communication with the five interstate pipelines serving the region in order to assess system conditions. On Jan. 3, ISO-NE and the Northeast Gas Association held a conference call to discuss the upcoming cold weather and areas of concern to both industries, and daily communication continued, as usual, through the cold snap, the summary added.
“When a constraint occurred on a pipeline outside New England, the inter-industry communications were extremely helpful to the ISO in order to be able to understand the abilities of the pipeline system in real time and for the immediate future,” the summary said.
While most of the pipelines were operating at or near capacity, a significant amount of the New England gas fleet was offline due to economics or they were burning their alternate fuel.
On the peak hour – from 6 to 7 p.m. – on Jan. 7, the energy produced by generators in New England, by fuel type, arranged by percent of total generation was:
- Natural gas: 25%
- Oil: 25%
- Nuclear: 23%
- Coal: 11%
- Hydro: 9%
- Renewables: 5%
- Wind: 1%
- Other: 1%
Over the evening peak, from 6 to 7 p.m., on Jan. 7, the natural gas percentage of New England generation was relatively low while oil, which on average produced less than 1% of the energy in 2012 and 2013, was contributing 25% and coal was producing 11%.
The summary further noted that ISO-NE was able to meet demand and reserve requirements and on Jan. 7, to provide 500 MW requested by PJM from 3 p.m., to 11 p.m.
New York ISO
The NYISO spokesperson said that the RTO responded to FERC’s request on Jan. 10, and that NYISO’s response is not available at this time.
In a Jan. 7 statement, NYISO said it called for the activation of voluntary demand response programs statewide between 4 p.m., and 10 p.m., to support electric system reliability throughout the Northeast and Midwest regions as frigid weather conditions affected electricity use and power production.
The NYISO also encouraged consumers to help conserve electricity by adjusting thermostats to a comfortable but lower-than-normal setting if health conditions permitted, refraining from using major electric appliances and turning off unnecessary electric lights and appliances during that time period.
“System conditions will be tight today with some generating units either not at full capacity or unavailable as a result of the extreme cold, icing conditions and high demand for natural gas,” NYISO President and CEO Stephen Whitley said in the statement.
On Jan. 9, the NYISO said that it successfully met a new winter record peak demand for electricity of 25,738 MW on Jan. 7. The previous record winter peak demand of 25,541 MW was set on Dec. 20, 2004.
Record-low temperatures in many portions of the United States resulted in a challenging day for electric system operators in New York, New England, the mid-Atlantic and the Midwest, Whitley said in that statement.
“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,” he said.
The NYISO and neighboring grid operators, including ISO-NE, PJM, Hydro Quebec and the Ontario Independent Electric System Operator continue to work together on initiatives to improve coordination and communication. NYISO added that it was able to import power on Jan. 7 from ISO-NE and Ontario over the evening peak hours and export power to help the PJM region.
Also, the NYISO’s demand response programs, which reduce energy use at peak times, were activated to help support regional reliability and manage demand.
On wind power, the NYISO noted that it had the benefit of more than 1,000 MW of wind power throughout much of the day on Jan. 7.
The NYISO also highlighted certain challenges, noting that extremely cold temperatures can cause equipment problems on the electric system, such as reduced pressure in high voltage circuit breakers, icing in rivers for hydroelectric plants and frozen pipes and valves associated with outdoor auxiliary systems.
While the state benefits from a diverse fuel mix for its generation fleet, natural gas fuels the largest percentage of the generation portfolio.
The NYISO added that 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. That 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.
Those weather and system dynamics can make meeting a 25,738 MW record peak in the winter just as challenging as meeting the record peak of 33,956 MW experienced last summer, the NYISO said.