ATC Information

ATC Information

Duke Energy Carolinas Available Transfer Capability (ATC) calculation methodology can be found in Attachment C of the Duke Energy Carolinas' Open Access Transmission Tariff. This page also contains other information related to the ATC calculation methodology.

Who To Contact

Previously Requested Data Used In The Calculation Of ATC/TTC

TRM/CBM Information

Forecasted/Actual Load

Revision History

Questions About ATC/TTC:

Customers wanting to learn about Duke energy Carolinas' ATC calculation Methodology, are encouraged to look over Attachmet C of the Open Access Transmission Tariff, and the information presentend on this page.

Customers with questions on the ATC/TTC values or calculation methodology can find the contact information on the Contacts Information page.

For the entire list of contacts regarding questions about other services such as Transmission Service Requests, tagging, ATC/TTC, Business Practices, Generator Interconnections, etc. please go to the Contact Information page on the left pane of OASIS or http://www.oatioasis.com/DUK/DUKdocs/Contacts.htm.

Previously Requested Data Used In The Calculation Of ATC/TTC:

Data used in the calculation of ATC/TTC is publicly available upon request subject to CFR §37.6.b.2.ii. All data requested and granted is posted to this site. To request data used in the calculation of ATC/TTC can find the contact information on the Contacts Information page.

Requested ATC/TTC Data

New requests are in red.

Customer	Affiliate	Contact Name	Date Info Requested	Requested Information
Duke BPM	Yes	George Burner	12/04/07	TTC Limits for 12/04/07
Constellation	No	Deral Danis	09/12/08	Seasonal base case, sub, mon, & con files

TRM/CBM Information:

Attachment C of the Duke Energy Carolinas' Open Access Transmission Tariff describes Duke Energy Carolinas' TRM/CBM postings and calculation method. The following is a summary of these documents and the TRM/CBM page on OASIS at http://www.oatioasis.com/DUK/DUKdocs/cbm.html.

CBM:

Duke Energy Carolinas has not defined a need for CBM on any of its interfaces in the Operating, Operational Planning, or Planning Horizons. The importing and exporting CBM on all interfaces is set to zero. The reasoning is as follows:

Duke Control Area uses 12-hour line ratings in its calculation of TTC. When operating the system, Duke uses short-term or one-hour line ratings where available. This affords an operating margin for unexpected conditions or inaccuracies in data used in the TTC calculations.
Duke Control Area uses the single worst transmission contingency when calculating all TTCs. These transmission contingencies may be either inside Duke Energy Carolinas' Control Area or outside its boundaries. External contingency limits to TTC are verified with the owning Control Area before they are posted. Duke Energy uses adverse generation participation when calculating import TTC. This methodology is consistent with Duke Energy Carolinas’ planning criteria, and it allows Duke to operate the system consistent with NERC operating guidelines. Adhering to the criteria reduces the need to maintain additional margins on Duke’s interconnections.
In general, there are few limits to transfer that have been identified within the Duke Control Area. This fact further reduces the need for Duke to include CBM in its calculation of ATC.

TRM:

For Duke Energy Carolinas, TRM is dependent upon the direction of the transfer capability across an interface. For imports, each VACAR interface is set equal to the opposing control area’s share of the VACAR reserve requirement. The importing TRM on interfaces with non-VACAR control areas is set to zero until such time as contingency reserves are identified and contracted for on those interfaces. The TRM for exports on each interface is set equal to Duke’s contractual obligation to meet the opposing Control Area’s TRM requirement.

Duke Energy Carolinas’ position is that in order to declare TRM there should be a contractual obligation for reserves. When Duke has a contractual transmission reservation obligation to supply and/or receive capacity other than reserves, then Duke will show this amount as a discrete transmission reservation as opposed to TRM. For that reason, existing and new declared network resources are not counted under TRM.

If a Customer has questions about TRM/CBM they may contact Alan Pritchard (Duke Energy Carolinas) at 704-382-7463 or ACPritchard@dukeenergy.com

Forecasted/Actual Load:

Pursuant to FERC Order 890, Duke Energy Carolinas is required to post the Load Forecast and the Actual Load for each day. The numbers are provided to meet the requirements of FERC Order 890 and are not to be used as billing determinants.

The data at http://www.ferc.duke-energy.com/Load/Load.htm is created by the Duke Energy Carolinas load forecast system and is based on the best weather information available at the time the forecasts are made. The load forecast assumptions include the day of the week, whether the day is a holiday and which holiday it is, prior year load patterns, and weather conditions or forecasts. Weather forecasts are available at: NOAA Weather as well as on commercial websites.

If a Customer has questions about Forecasted/Actual Load they can find the contact information on the Contacts Information page.

Revision History:

02/10/09 -- Created page.