January 2012 Capital Investment - National Grid

Exhibit ___ (EIOP-19)Page 137 of 684Area DescriptionThe Genesee transmission study area includes National Grid assets within NYISO Zone B.The area includes assets as far west as Lockport and as far east as Mortimer. The systemconsists of several 115kV circuits between Lockport and Mortimer stations. Three circuitsgo directly from Lockport to Mortimer, three circuits go from Lockport to Batavia and severalcircuits in series connect Batavia and Golah. Today one 115kV line and one 69kV linetravel between Mortimer and Golah.Two 345kV circuits owned by NYPA travel parallel to this area from Niagara to Rochester.This area also includes some of the assets stretching between Mortimer in the WesternRegion and Elbridge in the Central Region.Within the Genesee study area, there are three distribution study areas: Genesee North,Genesee South and Livingston.The Genesee North study area serves approximately 44,300 customers. There are a totalof 51 distribution feeders that supply customers in this area. There are twenty 13.2kVfeeders, with four being supplied from 34.5-13.2kV transformers, and the rest are fed from115-13.2kV transformers. The thirty one 4.8kV feeders are all fed from 34.5-4.8kVtransformers. There are ten 34.5kV sub-transmission lines that supply the distribution stepdown transformers in the area.The Genesee South study serves approximately 37,100 customers. The study area isdefined by the region that includes the City of Batavia and the surrounding towns andvillages. It is located east of Buffalo and southwest of the City of Rochester. The primarydistribution system voltages in Genesee South are 13.2kV and 4.8kV. Most of the 13.2kVsystem is fed from the area 115kV transmission system. The rest of the 13.2kV system, aswell as the 4.8kV system, are fed from a 34.5kV sub-transmission system supplied out of theNorth Akron, Batavia, North Leroy, and Oakfield substations. There are several customerssupplied directly from the sub-transmission system.The Livingston study area serves approximately 21,700 customers. The study area is madeup of Livingston County which is south of Rochester and east of Batavia. The primarydistribution system voltages in Livingston are 13.2kV and 4.8kV. Most of the area is fed froma 34.5kV sub-transmission system supplied out of the Golah and North Lakevillesubstations. There is also one 13.2kV station fed directly from the 115kV and some 69kVsub-transmission in the area.V - 23138