During January 2004, New England experienced some of the most extreme winter weather in recent history. As a result, ISO New England and NEPOOL have filed with the FERC enhancements to our current markets to help alleviate potential situations that could impact the reliability of the New England grid during such extreme cold weather conditions. Appendix H primarily addresses the need for electric scheduling certainty necessary to support Day-Ahead gas nominations by owners of natural gas units. In addition to enhancing the coordination of the gas and electric markets Appendix H also defines processes that will enable the ISO to forecast and operate with greater certainty and facilitate higher unit availability during Cold Weather Conditions.
There are three distinct levels of weather situations that may precede ISO New England calling a Cold Weather Event:
- Cold Weather Conditions means any calendar day when that day's Effective Temperatures are forecast to be equal to or less than zero degrees Fahrenheit for any single on-peak hour and that day's total Effective Heating Degree Days are forecast to be greater than or equal to 65.
- Cold Weather Watch means Days when Cold Weather Conditions are forecast to exist and the 7-Day Capacity Margin Forecast indicates a capacity margin greater than or equal to 1,000 MW.
- Cold Weather Warning means Days when Cold Weather Conditions are forecast to exist and the 7-Day Capacity Margin Forecast indicates a capacity margin less than 1,000 MW. In addition, a Cold Weather Warning will be used for all future days within the 7-Day Capacity Margin Forecast when a capacity margin of less than or equal to 0 MW exists for days not yet declared as a Cold Weather Event.
- Cold Weather Event means Days when Cold Weather Conditions are forecast to exist and the 7-Day Capacity Margin Forecast indicates a capacity margin less than or equal to 0 MW for an Operating Day. Cold Weather Events are declared by 1100 hrs two days prior to the Operating Day. A Cold Weather Warning will be used for all future days within the 7-Day Capacity Margin Forecast when a capacity margin of less than or equal to 0 MW exists, until such time that the ISO declares a Cold Weather Event.
ISO New England will declare a Cold Weather Event by 11:00 a.m. two days prior to the operating day of the Event unless circumstances require a later notice. Customer Support will initiate notification by posting a Cold Weather Conditions Notice in the ISO New England Calendar on the Web site. This action automatically generates an email communication to all who have subscribed to the Cold Weather Event Operations Mailing List. If you are interested in receiving notices associated with Cold Weather Watches, Warnings or Events, you can subscribe to the mailing list.
An operating day that has been defined as a Cold Weather Event day will see the Day-Ahead Market closing at 0900 hrs the day prior to the Event Day. The results of that Day-Ahead Market will be posted at 1200 hrs. This also means that the time associated with the Re-Offer Period for the Event Day will commence at 1200 hrs and close at 1400 hrs.
The only special consideration is for resources anticipating Extraordinary Fuel Expenses. These resources must enter their incremental energy offers up to the maximum level accepted in the eMarket application. The day prior to a Cold Weather Event Day Supply Offers must be submitted by 0900 hrs. There are no additional fields within the eMarket application that need to be completed. As always Supply Offers must represent the full capability of the resource and adhere to Market Monitoring and Mitigation provisions.