National Grid
ICAP Calculation ICAP Calculation for Load Serving Entities (LSE's):

The Installed Capacity (ICAP) for each Load Serving Entity (LSE) is calculated by the NYISO from information provided by National Grid. The reported ICAP is based on the aggregate of each LSE's customers' contribution to the NYISO peak load during the preceding year. The individual customers' contributions (tags) are estimated annually. The daily LSE requirements are then calculated by tracking customer enrollment changes and shifting load accordingly. Customers' contributions to ICAP are estimated from either their actual peak hour use if the customer is billed from interval data, or load profiles if they are billed on a load shape.

View details of National Grids methodology for calculating each customer's contribution to ICAP (pdf) for power year beginning 5/1/23.

National Grid provides ICAP values for individual accounts upon request. An approved ESCO can obtain ICAP values for prospective customers and existing customers by sending EDI historical usage transaction. If the ICAP value cannot be obtained via EDI, then a ticket would need to be requested through the Right Now Portal at Please include the account numbers for which you are requesting to receive the ICAP values. If you are requesting more than 25 accounts, please provide an attachment in the email in either excel or text format containing all the account numbers for which you are requesting ICAP values.

More details can be found on ICAP Requirements by visiting

To view load profiles (including EDI Load profile codes) used for ISO true-up for fifteen service classifications, please visit Load Profiles.

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