Rosslyn, VA, September 13, 2004 -- In response to a Federal Register notice on issues relating to the identification, designation, and possible mitigation of transmission bottlenecks, the National Electrical Manufacturers Association (NEMA) has submitted comments to the U.S. Dept of Energy''s Office of Electric Transmission & Distribution, calling for DOE leadership in resolving transmission bottlenecks.
Growth in demand for electricity and the increase in regional electricity trade have taxed transmission lines nationwide. Meanwhile, investment in new transmission facilities has significantly declined over the past 25 years. This contradiction has led to bottlenecks, which are economically inefficient and threaten the safe and reliable operation of the transmission system.
NEMA contends that, while it is in favor of identifying and eliminating bottlenecks, it is concerned that a lengthy process is under consideration. The association urges the secretary of energy to "exercise leadership in the resolution of transmission bottlenecks," as he did in two cases in California and New York.
Although the reduction of some transmission bottlenecks would require the construction of new transmission corridors, NEMA believes that many can be relieved by upgrading existing transmission corridors, which would minimize the impact on the environment and the public. NEMA recommends several approaches using currently available technologies, including:
- increasing transmission and distribution line capacity through the use of higher voltages and larger conductors;
- installing high-temperature, low-sag conductors for increased power flow in existing corridors;
- using high-voltage direct current (HVDC) transmission to increase capacity, better control power transfer, and improve overall system stability;
- adding peaking power units at substations, where power goes from sub-transmission to primary distribution;
- building intelligence into the grid through the installation of flexible AC transmission (FACTS) technologies and wide-area controls;
- and applying new analytical software models to better calculate stability and thermal limits in real time.
"We are running out of time in which to make improvements to our infrastructure," says NEMA president Malcolm O''Hagan. "Last year''s blackout illustrated the fragility of our existing transmission system. It is time to move forward."