As population growth and extreme temperatures strain the United States power grid, utilities and equipment manufacturers are looking for ways to increase the amount of electricity the grid can carry. The Powerline Conductor Accelerated Testing Facility, or PCAT, located at the Department of Energy’s Oak Ridge National Laboratory, is one of the only facilities in the country where companies can try out new transmission line technologies for long time periods in extremes of wind, weather, temperature and electrical load conditions.

 “We’re looking at the impact of new materials, advanced coatings, coating methods and integrated features, to understand how they compare to existing technology,” said ORNL’s Brian Rowden, PCAT manager. The research generally has some combination of three goals: increase the amount of current the line can handle, increase the operating lifetime, and reduce the operating temperature through materials and design choices.

PCAT is a test bed consisting of isolated power transmission lines mounted in spans across three towers and monitored by a suite of sensors. Testing is funded by users or through federally funded collaborations. The outdoor lab is used to monitor the performance of new conductor materials, sensors and controls, as well as coatings. 

Recently, PCAT was used for extended testing of a robot-applied coating called E3X, invented and patented by Prysmian, a multinational cable manufacturing company. On a baking hot summer day – the kind that can reduce the current that power lines carry or cause them to sag dangerously close to trees — technicians hauled the robot skyward in a bucket truck. Resembling an oblong, open box of metal tubes twined with colorful wires, the robot dispensed the coating as it traversed the power line. 

The product reduces the amount of heat retained in the cable. This allows the existing power line to carry more current, essentially increasing its capacity without replacing the line, said Joe Coffey, director of overhead transmission for Prysmian. To measure the potential improvement, an uncoated power line was compared to a coated version as both endured the same loadings and weather conditions for almost six months.

This Oak Ridge National Laboratory news article "Power line test bed energizes technologies for increasing grid capacity" was originally found on https://www.ornl.gov/news