Politicians say the new Royal Adelaide Hospital (nRAH) will struggle to cope with its first winter flu season.

SA Liberal Party health spokesperson Stephen Wade says the 800-bed nRAH would not be able to cope with demand, after numbers at the old RAH was “well above the capacity of the new hospital” this week.

“I'm concerned that when the flu season strikes the spike in demand for hospital beds will lead to the nRAH being overwhelmed from the very beginning of its operation,” he said.

The hospital is slated to open by winter, but Health Minister Jack Snelling says it will have more beds and better access to medical imaging in it emergency department.

“The new hospital is going to serve generations of South Australians, provide world-class healthcare in a way we just can't do in the old Royal Adelaide Hospital,” Mr Snelling said.

“It also means [staff] don't have to worry about isolating infectious patients because every patient has their own room.”

But Mr Wade insists the new hospital has only slightly more overnight capacity.

“It's well established that the old RAH, being an old facility with lots of nooks and crannies, has more flex capacity,” he said.

“One of the, shall we say implications of the single room approach in the new RAH, is that there's next to no flex capacity.

“Clearly the Weatherill Government's failure to manage the flow of patients means people are being log jammed. They're waiting for a bed.

“I'm very concerned that when the flu season strikes, the spike in demand for hospital beds will lead to the new RAH being overwhelmed from day one.”