Despite opposing a high-level nuclear waste dump in South Australia, state Liberal leader Steven Marshall is now proposing nuclear power as a potential solution to the state's energy reliability issues.

Mr Marshall made the claims after Wednesday night's load shedding, which meant 90,000 customers lost power during extreme heat.

That blackout followed other significant outages in recent months, including September's state-wide loss of power.

A citizens' jury rejected high-level nuclear waste storage in November, prompting Mr Marshall to declare plans of "turning South Australia into a nuclear waste dump" were "now dead".

But today he said that did not mean he or his party were against the production of high-level nuclear waste in South Australia, via nuclear energy generation.

"We've never ruled out the nuclear opportunity for energy. We made it very clear that we were not in the slightest bit interested in continuing to pour money into the hopeless case which was a nuclear repository in South Australia," he said.

"The royal commissioner ruled out nuclear energy in South Australia but there will be a time when it may become viable, and desperate times call for desperate solutions, and we are in a desperate situation."

Mr Marshall denied the policy was hypocritical, but did not offer an explanation as to what would become of the highly radioactive spent fuel rods if a nuclear reactor was built in South Australia.

He said all options should be on the table to "get baseload back in South Australia", including restarting the decommissioned Port Augusta power station — despite the demolition of one of its chimney stacks.

"We need to consider reopening Port Augusta, we need to consider solar thermal, we need to consider nuclear opportunities, we need to consider pumped hydro," he said.