How Aerospace Technology is Improving the Efficiency, Capacity and Reliability of the Electric Grid

For over one-hundred years, electricity has been delivered to consumers using bare overhead conductors that were made up of conductive aluminum strands commonly wrapped around a core that consisted of steel wires. As demand for electricity grew and new sources of generation were brought on line, many transmission and distribution lines became thermally constrained. The relatively high coefficient of thermal expansion ("CTE") of the steel core and aluminum strands, cause the conductor to sag as temperatures rise.

Recognizing the enormous challenge of increasing transmission line capacity, mitigating thermal sag, and improving conductor efficiency, CTC Global, of Irvine, California, USA, began developing the patented ACCC conductor in 2002. As the project evolved, CTC developed a hybrid carbon and glass fiber core that resisted degradation from UV, chemical, thermal, and cyclic load fatigue.

The ACCC conductor's increased aluminum content compared to any other conductor of the same diameter and weight also helps reduce line losses by 30 to 40% under equal load conditions.

A reduction in line losses offers the utilities and society in general huge advantages. Not only can more electricity be delivered from existing sources of generation as demand increases - under normal load conditions - fuel consumption can be reduced. While reduced fuel consumption reduces costs, it can also reduce associated emissions.

Considering that the reduction of emissions represents such a significant challenge for the utilities today, reconductoring an existing line with ACCC conductor is by far the cheapest and fastest way to achieve that objective. It's often been said that it's much cheaper to save a "NegaWatt" than it is to produce a MegaWatt.

In 2007, American Electric Power (AEP) reported that by simply reconductoring an existing 20 km line with ACCC conductor, they reduced losses by 0.9 MW and also reduced overall system losses by an additional 0.2 MW, for a total improvement of 1.1 MW. To date, American Electric Power has completed eight ACCC conductor installations. In the next few months, with the help of Quanta Energized Services, they will begin the largest energized reconductoring project in history by upgrading 240 circuit miles of double bundled 345 kV conductor using ACCC.  CTC Global will be providing more than 1,665 miles of ACCC to support this project. 

Proven Reliability at over 220 Project Sites

How to Select a Conductor 

To help make conductor selection easier, CTC Global developed a conductor comparison program known as CCP.  The program is designed to help system planners and engineers compare the ampacity, line losses, thermal and ice load sag, and economic aspects of nearly any conductor type and size, so the numerous advantages of the ACCC conductor can be fully realized. The user simply selects the conductor types and sizes from drop down menus and enters the appropriate values & assumptions highlighted in the yellow boxes. The program is fully functional and uses standard industry formulas (such as IEEE 738-2006). Outputs are readily comparable to Sag10�, PLS CADD™ and other similar programs. (Note the screen shot below) The steps are simple: