The three diesel-powered turbines at the Snuggery were mothballed recently and are scheduled to close in just over three years.
The peak demand turbines have the capacity to generate 21MW each but private owner ENGIE said it was not a profitable operation.
ENGIE chief executive Rik de Buyserie explained the reasons for the closure when he addressed an energy conference last month.
“Unfortunately, ENGIE earlier this year took the decision to remove our 63MW Snuggery and 75MW Port Lincoln power stations from service, and brought forward the closure dates of these assets from 2030 to the end of 2027,” Mr de Buyserie said.
“Without revenue streams that recognised the capacity value of this plant, Snuggery and Port Lincoln were no longer profitable, and we needed to take this decision on behalf of our shareholders.
“There was no single individual action that led to this decision, but we do need to remind ourselves that each and every time we choose to support one technology or a single asset type in the market, it has a flow-on impact on existing fleet, especially larger thermal assets.”
The Snuggery power station was erected on the Princes Highway in 1978 by the state-owned Electricity Trust of South Australia.