January 2012 Capital Investment - National Grid

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Exhibit ___ (EIOP-19)Page 47 of 684and crumbling foundations especially some of the tower supports. The containment pitaround the single phase transformers of TB#4 have collapsed in sections. The 115kVyard has inadequate thermal performance with respect to the existing transmissionsystem in the Capital/Northeast Region, which will be exacerbated by the addition ofGlobal Foundries (Luther Forest) and projected load growth. This will worsen with timeas Global Foundries is connected to the Northeast Region transmission system and asthe load grows as projected.Given the uncertainty over the 230kV station and the necessity to reduce capitalinvestment to minimize Plan costs, the Company has postponed both the 230kV and115kV rebuilds at Rotterdam. Any asset issues that arise will now be managed throughthe normal damage / failure process.Dunkirk (C05155) $0.25mDunkirk is a 230/115kV station located south of Buffalo, connected to 522MW ofgeneration owned by NRG. The Company retains ownership of most of the 230kV and115kV switch yard; however, the controls are located in the generation control roomowned by NRG. This station has recently experienced several 230kV misoperations dueto control cable issues as detailed in the 2010 Asset Condition report. Completereplacement of control cables is not possible due to space constraints in shared areas.In addition, portions of the station may require significant modification to conform toNPCC requirements.A project was completed in September 2010 to install a new cable trench in the 230kVyard. Control cables deemed “faulty” can then be replaced using these new facilities. Athorough conceptual engineering analysis to construct a new control house andcompletely separate assets in this station has been finished. Other equipment atDunkirk, such as disconnects and PTs (potential transformers), will be replaced during aseparate project to install a second bus tie.Lockport (C35464) $0mLockport is a 115kV transmission station with thirteen 115kV transmission lines tyingthrough the East and West bus sections. This station is critical to the 115kV systemoperations of Western New York. The overall condition of the station yard and controlroom is poor. As discussed in the 2011 Asset Condition report, work is required oncontrol cable duct banks, breaker operators, steel structures and concrete foundationsthat are deteriorated significantly. In addition, support column and breaker foundationsare in a deteriorated condition and need to be repaired with several potentially needingfull replacements. 18 The control room building is also in very poor condition withincreasing costs to maintain the original roof and the brickwork.There are two new 115kV SF6 breakers at Lockport, while the remaining 115kV oil filledBZ0 breakers show exterior corrosion and oil leaks. Three of the 115kV oil breakershave hydraulic mechanism leaks common to the BZO style breakers and failures ofhydraulic system components have been increasing. Each of the BZO breakers also has18 Report on the Condition of Physical Elements of Transmission and Distribution Systems, Case 06-M-0878 October 1, 2009, Page III-74 to III-76.II-3048
Exhibit ___ (EIOP-19)Page 48 of 684bushing potential devices which have been another source of failure. Ongoingmaintenance of the breakers is addressing the oil leaks.Given the number of transmission lines at the Lockport Station and the deterioratedconditions of the structures and controls that support them, a station rebuild is proposedto prevent future outages caused by equipment failures.Further work at the Lockport Station has been deferred in order to manage and reducecapital investment. However, delaying the rebuild maintains current risks associatedwith the asset condition issues noted above.Huntley (C11496) $0National Grid has started the process to investigate Huntley substation asset conditionneeds. Among the needs are: permanent capacitor banks at the Huntley 115 kV bus toreplace the mobile banks currently there; improved grounding in the switchyard; removalof all National Grid controls, batteries and communications equipment from inside theHuntley Generating Station to a control house in the yard (both 115kV & 230kV); addinga second station service supply; refurbishing the existing oil circuit breakers; replacingthe potential transformers; installing new CCVTs for 115 kV and 230 kV relaying; andrefurbishing the 230 kV cable pumping plant.While conceptual engineering was completed in 2011, no further work is planned atHuntley in the Plan period in order to reduce and manage short-term capital investment.However, delaying rebuild of the Huntley station maintains the current risks associatedwith having National Grid assets located in separately owned control rooms, such asmisoperation, inconsistent maintenance and uncontrolled conditions and access.Lighthouse Hill (C31662) $1.5mThis facility is a significant switching station with two 115kV buses and seventransmission lines connecting to the station, allowing power to flow from the Oswegogenerating complex to the Watertown area in the north and Clay Station in Syracuse.Seven OCBs are located 200 feet from the Salmon River located about 70 feet belowthe yard elevation. The station is located a mile up-stream of the New York StateWildlife Fish Hatchery. Although the risk is low, any significant oil spill in the stationwould have a detrimental environmental impact. Even at 70 feet above the river levelthere is also the risk of a flooding event at the station given its proximity to the river. Inaddition, the disconnect switches are in a very poor condition.Another significant issue at Lighthouse Hill is that the land is owned by Brookfield Powerand operated as a shared facility under a contractual agreement. The lack of directaccess to Brookfield’s control room at Lighthouse Hill is not ideal as it limits theCompany’s control over the housing conditions for the battery and relay systems. TheCompany has controls on the first floor of the control house which is immediatelyadjacent and downstream of Brookfield’s hydroelectric dam. An uncontrolled releasefrom the dam could flood the control room area. Flooding in the area occurred asrecently as October 1, 2010 due to a rain event.II-3149
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January 2012 Capital Investment - National Grid

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