Electricity Trust of South Australia builds major interconnector project linking with Victoria in late 1980s

The Electricity Trust of South Australia in the late 1980s handled the major interconnector project linking with Heywood in Victoria, drawing on its tradition of managing projects (see top inset) and developing into a sophisticated organisation with assets such as its helicopter fleet. 
Images by awesomeadelaide.com (project team) and David Tanner (helicopters).

The $140 million power connector between South Australia and Victoria, officially opened by premier John Bannon on March 30, 1990, brought big financial and infrastructure benefits to South Australia.

A change in thinking toward a national energy market led to the 1980 Zeidler committee of inquiry into “Electricity generation and sharing of power eesources in southern eastern Australia” that recommended electricity providers in New South Wales and Victoria place a premium on an interconnection with South Australia. The eastern states had plenty of electricity to share as a result of was installing capacity from zealously overestimating expected demand in the 1980s.

On the other hand, the Electricity Trust of South Australia had been hit by challenges such as the 1983 disastrous bushfires and a strong national push for structural reform and even privatisation of the electricity industry.  

Twenty-five departments of the Electricity Trust of South Australia were involved in the building the interconnector to link up with Haywood in Victoria. The first phase planning to allow a maximum of 500MW of power to be imported into South Australia and to export up to 250MW back to Victoria if required.

By July 1987, the route of the transmission line network had been approved and survey work started, with major construction work under way by October. ETSA and its contractors were under intense pressure to have the transmission interconnection running on schedule but work was affected by the extremely wet winter of 1988. Heavy vehicles used to shift equipment and materials for the transmission line cut their way across farmers’ soggy paddocks, leaving a trail of damage. ETSA compensation to these farmers was swift and meant big savings in the long run.

Among the infrastructure gains from the interconnector project was a second 275kV transmission line from Adelaide to Tailem Bend and a new 275kV double circuit transmission line from there to a new south=est terminal substation near Mount Gambier. A double circuit 275kV line from the state’s southeast met up with the Victorian 500kV network at Heywood in western Victoria.

John Welford, who'd been involved in planning ETSA’s generating capacity, contributed significantly to planning for a National Electricity Market in the 1990s.