Electric Utility Power Line Infrastructure: Feasibility of Converting Existing Overhead Lines to Underground

A Report Prepared by the Public Staff

Project Purpose & Objective

Assess the feasibility of undergrounding overhead electric distribution systems and provide a central source document for responding to continuing inquiries from the general public.

Scope

• Address the pros and cons of undergrounding electric distribution facilities
• Determine specific conversion costs for applicable line segments that comprise an overhead distribution system from the substation bus to the customer’s meter
• Address factors which impact the feasibility of conversions including physical restraints, coordination with other utilities, right-of-way requirements, design considerations, impact on public and private property, traffic flows, and environmental concerns.

Outline

I. Introduction

A. Statement of Problem

B. Plain Language Definitions

II. Current Situation

A.   Fact Sheet Detailing CP&L, Dominion NC Power and Duke

1.   Service Area

2. Customers Served

3. Employees

4. Transmission

5. Distribution

B. Current Line Extension Regulations

1.   Overhead Extensions

2.   Underground Extensions

3. Areas Designated Underground

C. Distribution System

1.   Overhead

a. Currently Installed

b. Percent Overhead Added Each Year

2. Underground

a. Currently Installed

b. Percent Underground Added Each Year

III. Comparison of Overhead to Underground

A. Benefits and Issues

B. Reliability (Impact to normal operation and major storms)

C. Capital Costs

1. Transmission

2. Distribution

D. Operating and Maintenance Costs

E. Costs to Customer and Municipalities (as applicable)

F. Environmental Impacts

G. Cost to Other Utilities (CATV, Phone, fiber)

H. Long-term Costs to Operate and Maintain

I. Other Considerations

IV. Requirements for Conversion from Overhead to Underground

A. Time

B.  Resources

1.   Availability of Skilled Installation contractors

2.   Availability of Hardware

V. Alternative Power Line Design Considerations

A. Alternative Pole Design

B.   Alternative Line Design    

VI. Tree Trimming

VII. Safety

VIII. Failure Analysis

IX. Research Sources

Project Schedule

• Statement of Study Purpose and Scope
• Draft completion by January 21, 2003
• Presentation of Summary Outline to NCUC by January 22, 2002
• Presentation of Summary Outline to Governor’s Task Force on January 24, 2003
• Data gathering complete by March 15, 2003
• Draft Study Completed by May 1, 2003
• Final Study Completed by June 30, 2003