January 2012 Capital Investment - National Grid

More documents

Recommendations

Info

Exhibit ___ (EIOP-19)Page 73 of 684Underground CableVarious projects are in place to refurbish or replace sub-transmission undergroundassets to ensure the system continues to perform in a safe and reliable manner.Drivers:Failures of individual sub-transmission cables do not typically impact customer reliabilitysince the portions of the system where they are utilized are generally networked.However, because these systems are located below ground and are out of sight, failuresof underground sub-transmission cables can be difficult to locate and time-consuming torepair leaving the system at riskAs noted in the 2011 Asset Condition Report, there are approximately 1,100 miles ofsub-transmission underground cable. Approximately one-half are more than 47 yearsold and one-third are more than 60 years old. The sub-transmission underground cableasset replacement program replaces cables that are in poor condition, have had ahistory of failure or of a type known to have performance issues. Given the timerequired to design and plan large scale cable replacement projects it is advisable tobegin a replacement program.Customer Benefits:Through a proactive approach, cable replacement projects reduce the likelihood of cablefailures, and resulting exposure to the risk of extended outages.2011 to 2012 Variance:The projected program investment is shown in the table below. The decreased levels ofsub-transmission underground cable funding reflects recognition of the complexity of theunderground cable replacement work and the high concentration of work required in theWestern Division resulting in resource and outage constraints.Table III-11Underground CableProgram Variance ($millions)CIP FY12 FY13 FY14 FY15 FY16 FY17 Total2011 5.2 6.8 4.7 7.3 8.0 32.02012 - 2.1 1.9 3.2 2.9 1.4 11.6Not represented in the investment forecasts in the table above are four cablereplacement projects C28892, Buffalo 23kV Reconductor - Huntley; C28893, Buffalo23kV Reconductor - Huntley2; C28903, Buffalo 23kV Reconductor - Kens2; andC28894, Buffalo 23kV Reconductor - Kensington. These planned projects are includedin the forecasts for spending in the System Capacity and Performance SpendingRationale, in the Capacity Planning program, because they were also driven by loadingissues.III-15 1574
Exhibit ___ (EIOP-19)Page 74 of 684Metal-Clad SwitchgearDeteriorated metal-clad switchgear can be prone to water and animal ingress whichleads to failures from moisture, dust or animals. Visual surveys will detect suchdegradation, but cannot identify surface tracking where hidden behind metal enclosures.Identification of these concerns is more likely with electro-acoustic detection techniques.By using sensors to detect anomalous sound (acoustic) waves or electric signals in themetal-clad switchgear, it is possible to identify equipment condition concerns beforefailure. An initial review using this technique identified a number of locations for furtheraction as part of this strategy.For each substation, an analysis will be conducted to determine if direct replacement isthe best course of action or if an alternate means of supplying the load will beconstructed.Drivers:Metal-clad switchgear installed prior to 1970 have several factors that can lead tocomponent failure. Electrical insulation voids were more prevalent in earlier vintageswitchgear. Higher temperatures due to poor ventilation systems can degradelubrication in moving parts such as breaker mechanisms; and, gaskets and caulkingdeteriorate over time leading to ingress of moisture.Customer Benefits:The impact of each metal-clad switchgear event on local customers is usuallysubstantial, with nearly 3,000 customers interrupted for over three hours per event. Thisprogram would reduce the risk of such events and provide significant benefit to theaffected customers.2011 to 2012 Variance:The projected program investment is shown in the table below. The capital forecastreflects a prioritized replacement schedule for switchgear replacement based oncondition assessment data and analysis.Table III-12Metal-Clad SwitchgearProgram Variance ($millions)CIP FY12 FY13 FY14 FY15 FY16 FY17 Total2011 3.7 2.6 - - - - 6.32012 - 4.3 6.2 - - - 10.4The following specific projects are forecasted to have spending in excess of $1 million inany fiscal year:• Project C25139, Replace 13.8kV Metal-Clad Switchgear at Oneida Substation.Replace metal-clad substation at Oneida substation with new metal-cladswitchgear.• Project C36104, Ash Street Replace Metal-Clad. Replace 12kV metal-cladsubstation at Ash Street substation with new open-air bus station.III-16 1675
Page 1 and 2:
Niagara Mohawk Power Corporationd/b
Page 3 and 4:
Testimony of Electric Infrastructur
Page 5 and 6:
Exhibit ___ (EIOP-19)Page 2 of 684T
Page 7 and 8:
Exhibit ___ (EIOP-19)Page 4 of 684s
Page 9 and 10:
Exhibit ___ (EIOP-19)Page 6 of 684A
Page 11 and 12:
Exhibit ___ (EIOP-19)Page 8 of 684M
Page 13 and 14:
Exhibit ___ (EIOP-19)Page 10 of 684
Page 15 and 16:
Page 17 and 18:
Page 19 and 20:
Page 21 and 22:
Page 23 and 24:
Page 25 and 26: Exhibit ___ (EIOP-19)Page 22 of 684
Page 75: Exhibit ___ (EIOP-19)Page 72 of 684
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
This document has been redacted for
Page 161 and 162:
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
Page 175 and 176:
show all

January 2012 Capital Investment - National Grid

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?