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1 Douglas E. Micheel Assistant General Counsel EP 01 Ninth Street NW Washington, DC Office 0..3 Fax delmarva.com dem 'I delmatva ~ power An Exelon Company August, 0 David J. Collins Executive Secretary Maryland Public Service Commission St. Paul Street, 1 Floor Baltimore, MD 10 Re: Case No. Dear Mr. Collins: Enclosed please find an errata to Delmarva Power & Light Company's Witness Karen R. Lefkowitz Direct Testimony in the referenced proceeding filed on July 0, 0 (M/L #). Please replace pages 0 and 1 with the attached, there were updates provided for overloaded transformers and target number of replacements. A red lined version is also enclosed for your convenience. Please contact me if you have any further questions. Sincerely, f!jl/jrj uglas E. Micheel Enclosure cc: All Parties of Record

2 1 Q. Please describe the basis for determining the financial benefit related to avoiding 3 A. this dispatch of service crews to address outages caused by storms. (OPR1) This benefit has been calculated by counting the number of avoided truck rolls and reduced crew time by improved knowledge of outages and also includes avoided suppo1i facility and personnel costs. The Company has developed an estimate of future financial savings by examining major storm activity over a prior 10-year period and forecasting the resulting number of avoided truck rolls and associated crew time. For future years, the annual savings amount was adjusted to reflect customer growth and inflation. 10 Q. Please describe the benefits relating to the identification of overloaded 1 A. 1 0 Q. 1 A. 3 transformers. (OPR - ) This AMI benefit results from the new capability to identify, schedule, and replace overloaded transformers prior to their failure. There are four primary benefits from this activity: 1) avoidance of unanticipated power outages due to transformer failures caused by overloading (quantified benefit OPR ), ) avoidance of transformer insulating fluid spills upon failure (unquantified benefit), 3) avoidance of more costly and time consuming emergency replacements by pre-scheduling Delmarva Power crews to replace transformers (quantified benefit OPR ), and ) improved power quality for customers (unquantified benefit). Please describe the basis for determining which transformers are overloaded. (OPR -) During 01 and 0, Delmarva Power analyzed over 1,000 transformers serving over,000 customers located on the 0 and 0 Priority Feeders. This 0

3 1 3 study identified 3 overloaded transformers that could impact nearly,300 customers. The overloading determination was based on occurrence of overloads of more than five hours in length that equaled or exceeded 0% of transformer nameplate capacity for overhead transformers. For underground transformers, the overloading determination was made based on overloads of more than five hours in length and a loading magnitude of 100% of transformer nameplate capacity. (The delineation in criteria between overhead and underground transformers is attributable to the ability of overhead transformers to dissipate heat into the outdoor air.) Hourly AMI energy data provided the necessary data for this analysis. The number of overloaded transformers throughout the service territory was then projected from this analysis and was estimated to be approximately 1, 00 transformers. The Company will begin to replace identified overloaded transformers during 0. As noted earlier, the forecast number ofreplaced transformers and the number of impacted customers is based upon the 0/ transformer loading study within the Priority Feeder Program. The Company has established a replacement target of approximately 0 transformer replacements each year for a total of 1,30 transformers over the next years. For future years, the annual savings amount was adjusted to reflect customer growth and inflation. The incremental costs of these transformer replacements prior to failure have been netted from the estimated benefits. 1 Q. Please describe the avoided outage cost attributable to replacing overloaded transformers prior to failure. (OPR ) 1

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5 1 Q. Please describe the basis for determining the financial benefit related to avoiding 3 A. this dispatch of service crews to address outages caused by storms. (OPR1) This benefit has been calculated by counting the number of avoided truck rolls and reduced crew time by improved knowledge of outages and also includes avoided support facility and personnel costs. The Company has developed an estimate of future financial savings by examining major storm activity over a prior 10-year period and forecasting the resulting number of avoided truck rolls and associated crew time. For future years, the annual savings amount was adjusted to reflect customer growth and inflation. 10 Q. Please describe the benefits relating to the identification of overloaded 1 A. 1 0 Q. 1 A. 3 transformers. (OPR - ) This AMI benefit results from the new capability to identify, schedule, and replace overloaded transformers prior to their failure. There are four primary benefits from this activity: 1) avoidance of unanticipated power outages due to transformer failures caused by overloading (quantified benefit OPR ), ) avoidance of transformer insulating fluid spills upon failure (unquantified benefit), 3) avoidance of more costly and time consuming emergency replacements by pre-scheduling Delmarva Power crews to replace transformers (quantified benefit OPR ), and ) improved power quality for customers (unquantified benefit). Please describe the basis for determining which transformers are overloaded. (OPR -) During 01 and 0, Delmarva Power analyzed over %,001,000 transformers serving over 3,000,000 customers located on the 0 and 0 0

6 1 3 Priority Feeders. This study identified -l-3 overloaded transformers that could impact nearly -00,300 customers. The overloading determination was based on occurrence of overloads of more than five hours in length that equaled or exceeded 0% of transformer nameplate capacity for overhead transformers. For underground transformers, the overloading determination was made based on overloads of more than five hours in length and a loading magnitude of 100% of transformer nameplate capacity. (The delineation in criteria between overhead and underground IO transformers is attributable to the ability of overhead transformers to dissipate heat into the outdoor air.) Hourly AMI energy data provided the necessary data for this analysis. The number of overloaded transformers throughout the service territory was then projected from this analysis and was estimated to be approximately 00 l, 00 transformers. The Company will begin to replace identified overloaded transformers during 0. As noted earlier, the forecast number of replaced transformers and the number of impacted customers is based upon the 0/ transformer loading study within the Priority Feeder Program. The Company has established a replacement target of approximately transformer replacements each year for a total of -001,30 transformers over the next -. years. For future years, the annual savings amount was adjusted to reflect customer growth and inflation. The incremental costs of these transformer replacements prior to failure have been netted from the estimated benefits. Q. Please describe the avoided outage cost attributable to replacing overloaded 3 transformers prior to failure. (OPR ) 1

7 CERTIFICATE OF SERVICE I hereby certify that on behalf of Delmarva Power & Light Company, the Errata to pages 0 and 1 of Karen R Lefkowitz Direct Testimony were sent by hand delivery, postage prepaid and/or electronic mail on this th day of August 0 to the below-listed parties in Case No.. Michael Dean Lloyd Spivak Maryland Public Service Commission William Donald Schaefer Tower Saint Paul Street, 1 ih Floor Baltimore, MD 10 William Fields Gary Alexander Ronald Herzfeld Maryland People's Counsel William Donald Schaefer Tower Saint Paul Street, Suite 10 Baltimore, MD 10 Courtesy Copy provided to: Margaret M. Witherup Gordon Feinblatt LLC 33 East Redwood Street Baltimore, MD 10