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Item No: A-4

January 16, 2014

Recent Weather 

Impacts on the Bulk 

Power System

Good morning Madame Chairman and Commissioners. I am here to provide an update on the 

bulk power system performance during last week’s extreme cold weather event. 

The information in this presentation is derived from details provided by NERC, the Regional 

Entities, and the reliability coordinators, along with some public sources. NERC continuously 

monitored the system during the polar vortex event and was in contact with both Commission 

staff and the industry through the week. Commission staff and NERC would like to thank all of 

the entities for providing us with additional information to support this presentation. We note 

that much of the information in this presentation is preliminary and subject to further 

verification and revision.

Last week, cold temperatures stressed the bulk power system with high loads, increased 

generator forced outages, and other challenging operating conditions. The bulk power system 

remained stable and generally performed reliably throughout the event. The credit for this 

good outcome goes to the many system operators and other utility personnel who worked long 

and hard, and communicated extensively with each other to keep the grid up and running.
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Jan. 6 – 8 Cold Snap

Monday, January 6 Tuesday, January 7

Temperature at 7 AM EST

Source: Ventyx Velocity Suite. 

Beginning on Sunday, January 5th and continuing through Wednesday, January 8th, a 

significant cold weather system moved across the Eastern United States. Temperatures were 

generally 20 to 40 degrees below normal for this time of year. For example, Monday 

temperatures remained around 15 degrees below zero in Minneapolis, and barely reached 10 

degrees in Nashville. Atlanta, meanwhile, experienced over 50 consecutive hours of subfreezing temperatures, and Indianapolis had 33 consecutive hours of sub-zero temperatures. 

For many areas, cold weather this severe and widespread had not been seen since the mid1990s. 
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Preparations

 Generator winterization

 Cancel scheduled outages

 Review unit fuel procurements

 Commit additional units

 Coordinate with neighbors

In the days leading up to the cold snap, system operators and generator owners took steps to 

prepare their systems and equipment for the freezing temperatures. For generators, such 

actions typically include the deployment of additional insulation, supplemental heating to 

prevent critical components from freezing, and dual-fuel capability testing. 

System operators worked to cancel or postpone scheduled outages, commit additional 

resources, request information about fuel restrictions, and ensure adequate staffing. MISO, 

for example, arranged for operating personnel to stay onsite to ensure full staffing during the 

event.

Neighboring system operators shared information with each other regarding weather 

forecasts, resource availability, and other pertinent information. This coordination continued 

as the weather event developed, as system operators with excess generation worked to make 

additional power available to neighboring markets.

The Friday prior to the cold snap, PJM filed an application with the Commission for a weeklong waiver of certain non-disclosure provisions in the PJM operating agreement. As granted 

by the Commission, the waiver allowed PJM to engage in unit-specific review of day-ahead 

plans with the interstate natural gas pipelines to help ensure that adequate supplies of 

natural gas were available and to confirm unit availability.

Earlier in the fall, the Commission conditionally accepted a series of ISO New England tariff 

revisions implementing the ISO’s Winter Reliability Program. Among other things, this program 

established an oil inventory service for oil-fired and dual-fuel units. The ISO has reported that 

oil was firing around one quarter of the total generation in the region at peak, roughly equal 

to the amount of generation burning natural gas.

In the aftermath of the event, system operators are comparing their next-day load 

projections to actual loads, and considering the need for any changes in their load forecasting 

models. 
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Natural Gas

 Record or near-record gas demand 

across the Eastern United States

 Pipeline capacity restrictions

 No unmanageable effect on bulk power 

system reliability

 System operators used their emergency 

coordination procedures

At this time, it appears that Midwest, Northeast, and Southeast regions set record demands 

for natural gas, while other parts of the Eastern and Central U.S. were near their all-time 

peaks. One compressor station outage on the Texas Eastern pipeline in Western Pennsylvania 

resulted in throughput reductions of nearly 600,000 decatherms per day, or about ten percent 

of the pipeline load. Most other pipelines curtailed interruptible or secondary firm 

transportation and storage services. 

While fuel restrictions certainly stressed the electric supply, system operators were able to 

maintain reliable electric service. In New England, for example, six units totaling around 

1,200 MW were not able to procure fuel initially when called intraday by the ISO. This 

request, however, was made on behalf of another RTO and did not affect power supply in 

New England. 

Electric system operators have also reported that their gas-electric coordination procedures 

generally worked well. For example, MISO contacted several gas pipelines starting on January 

3, and made subsequent schedule adjustments in order to ensure adequate generation.
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Other Fuels

 Coal

• Frozen stockpiles

• Quality issues

 Dual-Fuel / Oil

 Wind

• Turbine minimum operating temperatures

In addition to gas restrictions, system operators reported problems such as frozen coal 

stockpiles at coal-fired generating stations, and problems with fuel switching at dual-fuel 

units. Wind turbines were also affected by the cold, with some wind turbine models reaching 

their minimum operating temperatures. Two nuclear units tripped due to equipment 

problems, but it is not clear at this time if the problems were related to the cold 

temperatures. 

On the whole, preliminary data indicates that forced outages were significant in some 

regions. However, more analysis is needed to determine how much of this was weatherrelated. 

Demand response was also helpful during the event. For example, the New York ISO 

requested voluntary demand response on January 7th so that it could assist another RTO 

seeking resources. 
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ISO/RTO Peak Loads

0

50

100

150

Demand (GW)

NERC Winter

Assessment Forecast

Actual Peak Load

Source: NERC Winter Assessment & ISOs/RTOs. Data is preliminary.

Many system operators in the Eastern United States broke their winter peak demand records. 

MISO, SPP, ERCOT, PJM, and the New York ISO all set winter peak demand records, as did 

most of the utilities in the Southeast. 

NERC’s Winter Assessment, which was released last month, forecasted adequate reserve 

margins across the country for this winter. This forecast was based on “50/50” or average 

weather. Due to the extreme temperatures, the peak loads last week were often much 

higher than forecasted. For example, actual system loads exceeded the Winter Assessment 

forecasts by approximately 7 percent in PJM and around 9 percent in MISO.
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Midcontinent ISO

70

85

100

115

Jan 6 Jan 7 Jan 8

Demand (GW)

MISO

Source: Ventyx Velocity Suite. Data is preliminary.

New Winter 

Peak

MISO was the first region to be affected by the cold weather, setting a new all-time winter 

peak of nearly 110 GW on Monday. There were no problems attributed to the recent 

integration of the MISO South region, and the Reliability Coordinators in the area agreed to 

temporarily raise the MISO South transfer limit from 2,000 MW to 2,500 MW to allow 

additional power to be delivered to other regions.
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Southwest

Source: Ventyx Velocity Suite. Data is preliminary.

20

30

40

50

60

Jan 6 Jan 7 Jan 8

Demand (GW)

Emergency Alerts

& Demand Response

New Winter Peak

New Winter 

Peak

ERCOT

SPP

ERCOT issued an energy emergency alert, deployed demand response and made media 

appeals for conservation on Monday morning, but did not need to resort to additional 

emergency procedures. On Tuesday morning, ERCOT set a new winter peak demand record of 

over 57 GW, just slightly above the previous record peak from the February 2011 cold snap.

The SPP region established a new winter peak of nearly 37 GW on Monday. SPP issued an 

energy emergency warning for one balancing authority for a few hours, but did not need to 

use other emergency procedures.
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Southeast

0

2

4

6

8

0

5

10

15

20

Jan 6 Jan 7 Jan 8

SCE&G (GW)

Duke (GW)

Duke

SCE&G

Selected demand curves from OASIS Postings. Data is preliminary.

New Winter 

Peaks

SCE&G Load 

Shed

In the Southeast, many utilities set all-time winter peak demand records and issued calls for 

conservation. Duke Energy Progress and South Carolina Electric and Gas implemented voltage 

reductions on Tuesday morning. Several generating units also tripped in the SCE&G area, 

forcing the company to implement rotating outages and shed approximately 300 MW of firm 

load during the morning peak. The load was restored later in the morning.
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PJM

70

95

120

145

Jan 6 Jan 7 Jan 8

Demand (GW)

Source: Ventyx Velocity Suite. Data is preliminary.

PJM

Voltage 

Reduction

Demand Response

New Winter Peak

PJM experienced high loads and tight operating conditions from Monday evening through 

Wednesday morning. On Monday evening, PJM’s reserves were particularly tight, and the RTO 

directed member utilities to implement a 5% voltage reduction. The voltage reduction was in 

effect for around one hour.

On Tuesday afternoon, PJM set a new winter peak of around 141 GW. During this time, PJM 

deployed demand response and requested emergency energy purchases from neighboring 

markets, but did not need to invoke other emergency procedures.
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Northeast

10

15

20

25

30

Jan 6 Jan 7 Jan 8

Demand (GW)

Source: Ventyx Velocity Suite. Data is preliminary.

NYISO

ISO-NE

New Winter 

Peak

In the Northeast, the New York ISO set a new winter peak of nearly 26 GW on Tuesday. ISO 

New England was well below their all-time winter peak, and did not call for any emergency 

procedures. 

I will now turn it over to Mike Moon, Senior Director for Reliability Risk Management at NERC, 

who will provide an overview of NERC’s event analysis activities and lesson learned from the 

February 2011 cold snap.
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Context Event Analysis

• Always opportunities to 

learn

• Too early to draw 

conclusions

• Preliminary information and 

data

• Further analytical efforts

 Complete event analysis 

reports

 Determine root and 

contributing causes

 Identify trends

Event Analysis

Chairman LaFleur, Commissioners and staff, thank you for the opportunity to speak today. 

The Federal Energy Regulatory Commission, NERC and NERC’s stakeholders share a common 

interest in ensuring the reliability of the bulk power system of North America. Thus, as Mr. 

Burnham indicated, we have been working the past week with your staff and the utilities to 

gather the data you have just heard, and this data is consistent what we have learned from 

the industry.

However, the facts presented today should not be considered an event analysis. Rather, the 

preliminary data will help direct analytical efforts, which will include lessons learned and 

recommendations for further improving preparation and processes during extreme 

circumstances.

For example, forced generation outages in the most severely impacted areas of the Eastern 

Interconnection on January 6 and 7 appear to be minimally 50 GW. Upon a rudimentary 

analysis, this is higher than the historical wintertime average forced outage of 33 GW. 

Additional analysis is needed to understand the initial outage numbers in their overall context 

of performance relative to historical trends, recognizing that not all of the outages were due 

to weather.

The Event Analysis program is a fundamental and critical component that supports the 

electric reliability organization by providing insight and guidance through the identification 

and dissemination of valuable information to owners, operators and users of the bulk power 

system. The high level of stakeholder commitment to identifying lessons learned after events 

and striving to achieve the highest level of reliability is a primary foundation of this program. 

The ability to learn and develop sound recommendations and lessons learned for industry are 

the fastest way to proactively inform industry of reliability risks and provide positive steps to 

improve reliability. The continued encouragement of collaboration and voluntary disclosure 

of events and disturbances by registered entities is critical to this rapid learning and 

reliability focus. The ability to track lessons learned and measure impact is still maturing. 
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Lessons learned are now published with a survey capability to better gauge the industry use of 

these publications. Required reports have been received , and NERC staff is currently 

analyzing and identifying areas for further analysis.

TRE and ERCOT have already conducted some initial site visits. Event analysis reports will be 

submitted to NERC and the Regional Entities by registered entities. NERC and the Regional 

Entities will review each entity event report and conduct root cause analysis in coordination 

with the registered entities.
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• Thirteen published

 Seven - Generation

 Two - Transmission

 Four - Bulk Power System Operations and Procedural 

Control 

•NERC Operating Committee Guideline

 Generating Unit Winter Weather Readiness – Current 

Industry Practices 

2011 Cold Snap Event 

Lessons Learned

In addition to discussing data collection and analysis related to the recent polar vortex, I 

would also like to provide a brief synopsis of the lessons learned from the 2011 Cold Weather 

Event of February 1-5, 2011.

FERC and NERC released a joint staff report on the Cold Weather Event of February 2011. 

The report detailed 26 recommendations for the electric industry. Thirteen targeted lessons 

learned were published over the course of a year beginning in September of 2011. These 

lessons learned covered a range of critical functions from staffing, design, maintenance, 

operations and training. 

Using the key findings and recommendations from the Cold Weather Event Report, seven 

lessons learned were developed that focused on maintaining individual unit reliability and 

preventing cold weather related generation outages. These lessons learned detail 

preventative and corrective actions for cold weather issues that that can affect generation 

facilities, such as unit design, freeze protection, fuel switching, required onsite materials and 

resources, and training personnel. 

Two lessons learned focused on transmission equipment during winter weather situations. 

These lessons learned addressed issues related to transmission equipment outages and 

recommend that transmission facilities be inspected for areas where water could collect and 

freeze. Pressurized gas and oil systems must be maintained at adequate parameters to safely 

operate during extreme cold, especially in geographic areas not accustomed to freezing 

temperatures.

Four lessons learned focused on reliable BPS operation and situational awareness during cold 

weather events. Impacted entities must maintain an accurate and shared understanding of 

available and committed capacity resources on a real time basis. Improved coordination 

between gas and electric entities will ensure maximum generation with available firm gas 

supply and minimize non-firm gas supply generation with alternatives in place if gas becomes 

unavailable.
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Finally, in February 2013, the NERC Operating Committee drafted and published an extensive 

Reliability Guideline “Generating Unit Winter Weather Readiness – Current Industry 

Practices.” This guideline provided a comprehensive and detailed attachment that lists 

elements of a winter weather preparation procedure. These practices support all of the 26 

recommendations of the report. Coupling these guidelines with the annual webinars 

reinforces industry action. 

In conclusion, while we are still in the preliminary stages of analysis, we have established a 

solid foundation to learn from events and disturbances, to identify reliability risks and, 

ultimately, to further enhance reliability efforts. It is too soon to draw detailed comparisons 

of performance in 2011 versus last week, or assess the extent to which entities avoided the 

particular mistakes of 2011, but in broad scope certainly the overall outcome was better, 

which suggests that the efforts made since 2011 have yielded a change for the better. In 

terms of next steps, NERC and the Regional Entities will continue the efforts already 

underway to get the details of what happened and why from transmission operators, 

generators and others, so that we can identify any aspects of performance still needing 

improvement. This will be an extensive effort, but we are confident that we can reach the 

goal of maintaining last week’s good performance while improving any shortcomings that may 

later be identified. 

I wish to thank FERC for their invitation and attention. I will now turn back to FERC staff for a 

brief look at market prices during the event.
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Natural Gas 

Markets Stressed

Source: ICE and Weather.com

Area Hub Prices ($/MMBtu) Low Temperatures

1/6/14 1/7/14 1/6/14 1/7/14

Boston Algonquin Citygates $15.89 $34.14 29 12

Chicago Chicago Citygates $13.97 $7.49 -15 -12

New Jersey Tetco M3 $8.70 $31.86 19 4

New York City Transco Zone 6 NY $13.82 $56.59 21 4

Philadelphia Transco Zone 6 Non-NY $10.90 $70.66 13 4

Richmond Transco Zone 5 $11.16 $72.43 10 7

Rockies Cheyenne Hub $4.70 $5.91 -3 24

Gulf Coast Henry Hub $4.31 $4.50 

U.S. gas demand hit 137 Bcfd on Tuesday January 7, 11 Bcfd over the previous winter record 

set in the winter of 2008/9. Demand records were breached in the Midwest, the Northeast, 

and the Southeast, which added to constraints on pipelines delivering gas to the Mid-Atlantic 

and Northeast. Consequently, natural gas prices averaged over $70/MMBtu along the I-95 

corridor, between Richmond and New Jersey, with some intraday trades close to 

$100/MMBtu. Although greater access to Marcellus shale gas via the New Jersey-New York 

pipeline expansion gave New York City some relief, prices there still reached $57/MMBtu. 

Boston gas prices spiked less than New York and Mid-Atlantic prices, to $34, helped by slightly 

higher temperatures, backup oil generation, and liquefied natural gas (LNG). Gas prices in 

Chicago spiked to nearly $14/MMBtu on Monday, the highest in 10 years. 

Many interstate natural gas pipelines issued operational flow orders. Two unplanned 

compressor station outages on Spectra Energy’s Texas Eastern Transmission pipeline 

contributed to constraints into New York City and gas generator outages in PJM. A number of 

Northeast and Midwest local distribution companies reported pressure drops on their systems, 

asking non-essential customers to voluntarily curtail gas use. Well freeze-offs in some major 

producing basins reduced natural gas supply, just as demand was peaking. Supply from the 

Marcellus formation dropped by 1 Bcfd, but has since recovered.
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Electric Prices Follow Fuel 

Prices and Demand Rise

Source: Derived from Genscape

$0

$200

$400

$600

$800

$1,000

Mass Hub N.Y.C. Zone J Western Hub Indiana Hub

$/MWH On-peak Real-time Prices

5-Jan-14 6-Jan-14 7-Jan-14 8-Jan-14

In the electricity markets, on-peak average real-time prices soared to as high as $765/MWh in 

PJM and $510 in the NYISO as natural gas prices and demand spiked upward. 

Among the most stressed areas, system conditions in PJM included under-forecast load and 

more than 30 GW of generator outages. Prices on Monday rose to as high as $1,200/MWh 

during the evening peak when PJM implemented the 5% voltage reduction mentioned earlier. 

Subsequently, on Tuesday morning prices reached the administratively set price of 

$1,800/MWh for approximately 4 hours as emergency demand response was called. 

The cold weather forced natural gas and power prices higher in New York, New England, and 

MISO. New York requested voluntary demand response but demand response was not 

activated or requested in New England. Fuel oil had a $37/MMBtu advantage over natural gas 

in New York and a $13/MMBtu advantage in New England. Thus, oil-fired and dual fuel units 

could run economically given the spread between the fuels. By the end of the week the price 

spreads had reverted to normal levels with a price spread of approximately $19 once again in 

favor of natural gas.
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Item No: A-4

January 16, 2014

Recent Weather 

Impacts on the Bulk 

Power System

This concludes our presentation and we are happy to answer any questions you may have.