CONDITIONS IMPACTING TRANSMISSION CAPABILITY

CONDITIONS IMPACTING TRANSMISSION CAPABILITY*

* The Conditions Impacting Transmission Capability page is manually updated once per day to include transmission outages within the PJM footprint that may limit ATC. For a complete listing of all PJM outages, refer to page the PJM Transmission Facilities Outage List (this page is automatically updated every 5 minutes and can also be accessed from the Oasis System Information section).

Special Notices: Transmission Service

BGE is revising transmission circuit and transformer ratings in their transmission zone based on a comprehensive review of their facility ratings process.

PJM is reviewing the 500 and 230kV transmission circuit and transformer ratings which will be implemented on June 1, 2008. BG&E is making a concerted effort to prioritize transmission work during the month of May 2008 to address the impact of the 9 transmission circuit and transformer ratings changes on system operations. This will also necessitate both scheduled and emergency outages in May to complete the related transmission work.

The BGE rating changes effective June 1 are included in the attached document:

Emergency and Planned Outages are scheduled on the following 9 facilities during May to address projected operational/reliability concerns.

Circuit No	Location	eDART Ticket Numbers	Outage Dates
2314	HIGH RIDGE TO SANDY SPRING TAP	276710	5/8/2008
			1 daily outage
2334	HIGH RIDGE TO SANDY SPRING TAP	276712	5/9/2008
			1 daily outage
2344	BRANDON SHORES TO HAWKINS POINT	226517	5/5/2008 - 5/7/2008
	SOLLERS POINT TO RIVERSIDE		3 daily outages
		276755	5/20/2008 -5/21/2008
			2 daily outages
2345	BRANDON SHORES TO HAWKINS POINT	276774	5/19/2008
	SOLLERS POINT TO RIVERSIDE	276788	5/23/2008
		276789	5/24/2008
			3 daily outages
2310	CONASTONE TO NORTHWEST	231410	5/16/2008-5/18/2008
			3 daily outages

2322	CONASTONE TO NORTHWEST	276734	5/10/2008
			1 daily outage
2323	CONASTONE TO GRACETON	276753	5/28/2008
			1 daily outage
2313	GRACETON TO RAPHAEL ROAD	276749	5/12/2008-5/14/2008
			3 daily outages
	GRACETON 230-1	276754	5/27/2008
			1 daily outage

BGE is in the process of performing a comprehensive review of their 115kV facility rating. Results will be communicated via OASIS upon completion of the review.

http://www.pjm.com/etools/oasis/downloads/20080501-bge-ratings-changes-for-june-1-2008.xls

Mt. Storm – Pruntytown 500 kV line outage in April 2008

Update 4/14/08

Due to issues with the eMKT database, Mt. Storm – Pruntytown 500 kV line outage has been delayed from its original timeframe - April 15 thru 17, 2008 to April 16 thru 18, 2008 in order to ensure that the potential congestion during this outage is appropriately captured in the day-ahead market case.

East Towanda Sectionalizing Scheme

Update 2/28/08
Work was completed under eDART #237768 and the East Towanda #3 transformer was returned to service on 02/28 @ 2128. At that time the ~50% increase in ratings for all temperature sets on the transformer. An additional transmission outage will be required to return the Transformer to its per-July 2007 ratings, but that outage is not presently scheduled.

Update 2/19/08
Due to a revised work plan, FE East has submitted eDart ticket #237768 scheduled for 2/25-2/29. This outage replaces eDart ticket #230048, which has now been ‘cancelled’. Upon completion of eDart #237768, the East Towanda #3 transformer ratings will increase as described below in the 2/11/08 update.

Update 2/11/08
Upon completion of eDart ticket #230048, the ratings of the East Towanda #3 230/115kV transformer will increase ~50% for all temperature sets. However, an additional transmission outage will be required to return the Transformer to its pre-July 2007 ratings. This second outage has not yet been scheduled.

Update 1/15/07
On Thursday 1/10/07, the Operating Committee waived the 90-Day waiting period defined in PJM Manual M-03 and approved the immediate use of the East Towanda Automatic Sectionalizing scheme in Real Time Operations. The Sectionalizing scheme will restore the East Towanda 230kV bus and East Towanda - North Meshoppen 230kV line, following a fault on the East Towanda #4 transformer. This contingency and sectionalizing scheme will be screened in the PJM EMS. Any resulting overloads will be controlled to their Long Term Emergency rating. Also, in accordance with PJM Manual M-03, PJM will continue to screen for the loss of the East Towanda #4 transformer with the Sectionalizing scheme failing. All subsequent overloads will be controlled to their Load Dump rating.

In early July of 2007, FE East discovered the East Towanda #3 transformer was more limited by a low side bus conductor than the transformer itself. On July 19, 2007, FE East submitted a rating reduction of the East Towanda #3 transformer to PJM based upon the low side bus conductor limit. This rating reduction was immediately entered into the PJM EMS system and controlled to in Real Time Operations. This derate will remain in effect until the low side bus conductor can be replaced. The tentative date for this replacement is late March or early April. Any updates to this time frame will be posted to this webpage.

Black Oak SVC

Update – 11/20/07

The new Black Oak Static VAR Compensator is in-service as of 12/05/07. The device is capable of absorbing 100MVAR or producing 575MVAR to help regulate voltage and increase the transfer capability across the Black Oak-Bedington transfer interface.

WYLIE RIDGE STATION

Update – 11/20/07

The Wylie Ridge #6 345/500kV transformer is expected to be in-service on 12/20/07.

Wylie Ridge #8 345/500kV transformer was placed in-service on 9/9/07. The SPS has been physically removed and can not be re-activated.

**No longer applicable**

A Special Protection Scheme has been installed at the Wylie Ridge station in order to reduce the post-contingency flow on the Wylie Ridge 500/345 kV transformers and reduce congestion at this station. Upon the loss of a Wylie Ridge 500/345 kV transformer, the SPS trips the ‘WK1’ and the ‘WK6’ 345 kV circuit breaker to split the 345 kV bus so that the remaining Wylie Ridge 500/345 kV transformer is isolated on the Wylie Ridge-Tidd 345 kV line.

KAMMER 765/500kV TRANSFORMER DERATE

On 4/2/07, the Phase 2 transformer of the Kammer 765/500kV Transformer failed. The transformer will be repaired and returned to service with a different Phase 2 transformer, resulting in approximately a 2% reduction to the 86-Degree & 95-Degree Normal, Emergency and Load Dump Ratings. The 68-Degree and 77-Degree Normal Ratings will also be reduced by approximately 1-2%. No other temperature dependant ratings will be impacted.

EAST WINDSOR TRANSFORMER

Update – April 4, 2006

On Friday, March 3, 2006, the East Windsor #1 500/230kV transformer failed and is expected to have an extended outage. It will not be available for summer 2008 operations. For this summer's forecasted conditions, the outage of the second East Windsor 500/230kV transformer or the nearby Smithburg 500/230kV transformer, should not have a major impact on system reliability.

ALLEGHENY POWER EHV TRANSFORMERS

Update – August 15, 2005

This update provides additional information regarding the de-rating of the Wylie Ridge #7 EHV transformer. The Wylie Ridge #7 transformer was de-rated by approximate 13%. At this time, there are no plans to de-rate the parallel transformer (Wylie Ridge #5). The decrease in rating will impact congestion in the Wylie Ridge area and transmission service on those paths that are limited by constraints at Wylie Ridge.

Update – July 8, 2005

Allegheny Power has completed a portion of it’s analysis on several of their EHV transformers, located at Wylie Ridge, Belmont and Kammer. Initial results indicate a change or de-rate at Kammer and Wylie Ridge is required, while result and analysis of Belmont appears to require no change in ratings there. The de-rate at Kammer is being put place as soon as possible, while ratings for Wylie Ridge are still be review. Updated information will be posted as it becomes available.

WYLIE RIDGE, BELMONT AND KAMMER STATIONS

NEW FREEDOM STATION

As a result of the recent review of transformer performance parameters, the New Freedom 500-4 500/230 kV transformer has been de-rated by approximately 15%. No significant increase in congestion and off-cost operation is expected due to the decrease of transformation capability at New Freedom.

FACILITIES CURRENTLY OUT OF SERVICE:

East Windsor #1 500/230 kV transformer

Out of service March 3, 2006 thru June 1, 2008.

Hunterstown #1 500/230 kV transformer

Out of service January 21 thru May 16, 2008

Marquis – DOE #2 345 kV line

Out of service January 24, 2007 thru December 31, 2008

Marysville – Maliszewski 765 kV line

Out of service March 3 thru May 16, 2008

Kammer – Maliszewski 765 kV line

Maliszewski 765/138 kV transformer

Out of service March 3 thru May 30, 2008

Ox #2 500/230 kV transformer

Out of service March 3 thru May 31, 2008

Hanging Rock – Jefferson 765 kV line

Out of service March 3 thru May 2, 2008

East Windsor – Salem 500 kV line

Out of service March 29 thru May 8, 2008

Baker – Hanging Rock 765 kV line

Out of service March 31 thru May 2, 2008

Beaver Valley – Sammis 345 kV line

Out of service March 31 thru May 4, 2008

Greene – Sugar Creek 345 kV line

Out of service April 18 thru 30, 2008

Bedington – Black Oak 500 kV line

Black Oak – Hatfield 500 kV line

Out of service April 26 thru May 2, 2008

Surry – Chickahominy 500 kV line

Out of service April 27 thru May 15, 2008

Davis Creek – Braidwood 345 kV line

Out of service April 25 thru May 1, 2008

Burnham - Sheffield 345 kV line

Out of service April 28 thru May 1, 2008

Ladysmith – Chancellor 500 kV line

Out of service April 28 thru 29, 2008

East Lima – Fostoria 345 kV line

Out of service April 28 thru May 23, 2008

Pruntytown #1 500/138 kV transformer

Out of service April 28 thru May 30, 2008

FACILITIES EXPECTED OUT OF SERVICE:

MAY 2008 OUTAGES

Conastone – Hunterstown 500 kV line

Scheduled out of service May 3 thru 5, 2008

Zion – Pleasant Prairie 345 kV line

Scheduled out of service May 3 thru 16, 2008

Peach Bottom – TMI 500 kV line

Scheduled out of service May 5 thru 9, 2008

Homer City – Stolle Rd 345 kV line

Scheduled out of service May 5 thru 9, 2008

Hanging Rock - Marquis 765 kV line

Scheduled out of service May 5 thru 16, 2008

Kammer – W Bellaire 345 kV line

Tidd – W Bellaire 345 kV line

Scheduled out of service May 5 thru 8, 2008

Kammer - Maliszewski 765 kV line

Scheduled out of service May 5 thru 30, 2008

Mt. Storm – Valley 500 kV line

Scheduled out of service May 5 thru 8, 2008

S. Canton 765/345 kV transformer

Scheduled out of service May 5 thru 9, 2008

Conastone 500-2 500/230 kV transformer

Scheduled out of service May 11 thru 17, 2008

Conemaugh – Keystone 500 kV line

Scheduled out of service May 12 thru 30, 2008

Alburtis - Branchburg 500 kV line

Scheduled out of service May 12 thru 20, 2008

Jacksons Ferry - Axton 765 kV line

Scheduled out of service May 13 thru 15, 2008

Elmont – Chickahominy 500 kV line

Scheduled out of service May 14 thru 15, 2008

Conastone 500-3 500/230 kV transformer

Scheduled out of service May 18 thru 19, 2008

Cloverdale – Lexington 500 kV line

Scheduled out of service May 19 thru 22, 2008

Calvert Cliffs – Waugh Chapel 500 kV line

Scheduled out of service May 21 thru 23, 2008

Alburtis - Juniata 500 kV line

Scheduled out of service May 28, 2008

JUNE 2008 OUTAGES

Hanging Rock – Jefferson 765 kV line

Scheduled out of service June 2 thru 27, 2008

Belmont - Kammer 765 kV line

Belmont – Mountaineer 765 kV line

Belmont 765/500 kV transformer

Scheduled out of service June 2 thru 13, 2008

Cloverdale 765/345 kV transformer

Scheduled out of service June 2 thru 5, 2008

Cloverdale – Joshua Falls 765 kV line

Scheduled out of service June 9 thru 12, 2008

Tanners Creek – Miamifort 345 kV line

Scheduled out of service June 25 thru 26, 2008