Convention centre to boost SA economy

South Australia is expecting a near $2 billion return on its $397 million redevelopment of the Adelaide Convention Centre.

The final stage was opened on Wednesday and Premier Jay Weatherill says the centre will now attract greater investment in SA and support 1200 ongoing jobs.

"Our investment in the expansion and renewal of the Adelaide Convention Centre is expected to bring an extra $1.92 billion into the state's economy over the next 25 years," the premier said.

The centre now boasts 20,000 square metres of event space including a new 3500-seat plenary hall.

It is expected to fill to capacity in September when it hosts the 68th International Astronautical Congress where tech billionaire Elon Musk will be among the speakers.

Tourism Minister Leon Bignell said 95 conference events attracting more than 70,000 delegates had already been booked for the centre between now and 2020.

He said that would generate $200 million in economic activity.