Background

Progress Energy Carolinas maintains a network of about 6,000 miles of electric transmission lines (69 kilovolts and up) throughout its 34,000-square-mile service area in the Carolinas. The transmission network is the backbone of the electric grid throughout the region; it serves as the means of moving large amounts of electricity continuously from power plants to communities, where it is distributed to homes and businesses. High-voltage lines range in length from short, urban spans to longer cross-country routes.

Since electricity cannot be stored in large quantity, the transmission system must work 24 hours a day in tandem with the generation system to meet the needs of North Carolina and South Carolina residents and businesses. Any addition of power plants will require new transmission lines and facilities. The degree of needed transmission additions is based on a number of factors, most notably existing capacity and location.

Critical Infrastructure

Planning for the region's future electricity needs is a responsibility Progress Energy takes very seriously. As with other components of utility infrastructure, siting and building transmission lines is very difficult. It is also very expensive, often costing much more than $1 million per mile. The process can involve acquiring land easements from property owners, and creating a cleared corridor, 70 to 100 feet wide and often many miles long.

Adding large transmission lines also requires state regulatory approval, which involves significant permitting, research and modeling data, environmental information, cost comparisons, analyses of various options, discussions of scenarios and criteria used in evaluation, and other information.

Progress Energy evaluates customer needs continuously and looks out over long-range periods to determine future needs for power plants and transmission lines. The company reviews these 10-year siting plans annually with state regulators. Adding transmission can take many years - even in the most streamlined process. So decisions on system enhancements needed in the next decade must be made today.

New unit at Harris would minimize transmission needs

Progress Energy has announced that it might pursue expansion at the Harris Nuclear Plant site in southwestern Wake County. While a final decision on moving forward with the Harris Plant site is still years away, the company is acting now to keep the nuclear option open and viable. Adding a second reactor at the Harris Plant site would necessitate the addition of some electric transmission infrastructure.

But since the Harris Plant site was originally designed to accommodate multiple reactors, the site has sufficient transmission system capacity today. Therefore, our preliminary assessments indicate that large, expensive transmission additions might not be needed to accommodate a new nuclear reactor, should one be built. The need could change, but based on current available information, it appears the transmission investment for a new unit at the Harris Plant would be minor compared with other options.

Other Carolinas sites evaluated for new nuclear plants would have required the addition of numerous long transmission lines and related facilities at a cost, in some cases, of hundreds of millions of dollars.

Public involvement a key part of the process

Siting and building of any transmission line needed to accommodate a new unit at the Harris Plant would follow Progress Energy's time-tested process of ensuring public involvement in determining routes.

Progress Energy believes involvement of the public, including potentially affected property owners, is crucial in siting and building transmission lines. While it is impossible to build large-scale infrastructure without affecting some property owners, the company works to minimize impacts to the extent possible. The company uses a process that emphasizes significant public involvement, whenever possible, in determining route-selection criteria. Any potential route, regardless of how much can be located along roadways or other utility easements, means possibly affecting dozens, or even hundreds, of property owners.

Keeping the public involved and using input from landowners, local governments and others helps Progress Energy determine the best route for transmission lines and helps keep these critical electric system enhancements moving forward, so that energy delivery is as reliable tomorrow as it is today.