North American Clean Energy, Jul/Aug 2014, by D.C. Bryant.
http://www.nacleanenergy.com/articles/18221/improving-the-smart-grid-by-using-accc-conductor

"In the attempt to modernize transmission infrastructure, it’s important to re-consider the capacity, efficiency, and reliability of the conductors used in the Smart Grid. It’s worth recalling past experiences, and the lessons that underscore the significance of conductor sag, along with the limitations of computers and telemetry devices during peak demand periods, N-1 conditions, and other emergency conditions.