Skip to main content
First 735 kV AC Transmission System
Main Category
Date Created
Location Country
45.508272, -73.553696
75 Boulevard René-Lévesque

Hydro-Quebec's 735,000 volt electric power transmission system was the first in the world to be designed, built and operated at an alternating-current voltage above 700 kV. This development extended the limits of long-distance transmission of electrical energy. On 29 November 1965 the first 735 kV line was inaugurated. Power was transmitted from the Manicouagan-Outardes hydro-electric generating complex to Montreal, a distance of 600 km.

The large undertaking of building a 735 kV line was tackled by Jean-Jacques Archembault and the Quebec Hydro. In recognition of this great feat, the IEEE awarded Archembault the 1972 IEEE Habirshaw Award for pioneering the line. The line transported electrical power from the hydraulic centers of the Manicouagan River, in the North East of Quebec, to the load centers in the south of Quebec. It had important economic ramifications as well. the lines allowed the transmission of power from remote hydroelectric plants to load centers at a relatively low cost, thereby giving customers some of the lowest rates in the world. Due to the vast amount of materials required, including but not limited to insulators, spacers-dampers, and towers, it had an impact on national and international manufacturers. 

Image Credit
Courtesy Wikicommons/abdallahh (cc-by-2.0)
Image Caption
A pylon of the 735kV power transmission system.

We hope you enjoyed this essay.

Please support America's only magazine of the history of engineering and innovation, and the volunteers that sustain it with a donation to Invention & Technology.


Stay informed - subscribe to our newsletter.
The subscriber's email address.