Technology's Strategic Role
could ease the burden are becoming increasingly difficult to site. New technologies can enhance the value of existing transmission assets, while making the construction of underground facilities more feasible.
In particular, there is a pressing need for better control over the bulk-power system (em to alleviate bottlenecks, tame wayward loop flows, enhance system stability, and increase overall efficiency. In response to this need, EPRI has pioneered a high-tech Flexible AC Transmission System (FACTS), based on power electronics and designed to maximize power transfer over existing lines. Specifically, FACTS technology can increase or decrease power flow on particular transmission lines, enhance stability by counteracting transient disturbances almost instantly, and enable loading transmission lines closer to their thermal limits. On some lines, these power electronics controllers can increase available capacity by as much as 50 percent.
After more than a decade of research, FACTS is now entering utility service. The Slatt substation of the Bonneville Power Administration is currently demonstrating a modular thyristor-controlled series capacitor (TCSC) on a
2,500-megawatt (MW), 500- kilovolt (kV) transmission line. In April 1995, a Static Condenser (STATCON) will be commissioned at TVA's Sullivan substation, to provide reactive power compensation at the +100 Mvar level.
Another group of technologies is sharply reducing the cost of installing underground facilities, which represent up to 70 percent of total system costs. Low-impact boring technologies are making underground installation faster and less obtrusive, as well as less expensive. As a result, new
transmission facilities in many fast-growing areas may now actually be cheaper to install underground than overhead.
A major breakthrough in this area is the AccuNav guidance system for horizontal earth boring. Based on electronics developed for cruise missiles, this device rides along with the drill head and determines its location by sensing the earth's magnetic field. AccuNav and other guided boring technologies passed their most
difficult demonstration to date by traversing the Nacoochee Valley of northern Georgia last summer. The project installed a 2,500-foot, joint-free length of 115-kV cable through difficult terrain in an environmentally and historically sensitive area.
Dramatic changes are taking place in the way electricity is marketed at both the wholesale and retail levels. To compete in this changing marketplace, forward-thinking utilities need new analytical tools and procedures to manage their own market participation. Among the analytical products that can facilitate participation in more complex wholesale markets is POWERCOACH, an EPRI software package that uses an expert system to analyze trading decisions in light of a utility's own risk preferences.
At the retail level, utilities must also find better ways to compete for customers. Successful competitors will offer differentiated products and services that enhance the value of the power they deliver. One way to differentiate power is through the premium reliability offered by Custom Power. Another key approach is to differentiate prices, particularly through real-time pricing (RTP).
The main challenge in establishing more competitive retail markets for electric power is to improve the way supply and demand are translated into price. During a critical period of peak demand on a hot summer afternoon, for example, the marginal