Sydney's Powerhouse Museum will be shut for up to three years while $250 million building and conservation work is completed.

Arts Minister John Graham made the announcement and revealed updated concept designs for redevelopment to the science, technology, arts and design space in Ultimo on Monday.

"It's an exciting moment as we start to get this project back on track," Mr Graham said.

"It's been a rollercoaster nine years with real division in the community in the future of this site ... we take the next step today."

The Powerhouse Museum will close its doors in early February next year — a decision Mr Graham described as a "one-off, once-in-a-generation" opportunity to invest in the space.

"If we didn't do that, the strong advice to me as minister was we would be spending more money to get far less impact on this site," he said.

 

Art Minister John Graham said more public consultations will take place ahead of the refurbishment.

It comes after the Minns government faced criticism for cutting the rebuild allocation in half, with the saved funding going towards schools and hospitals.

The Powerhouse plans include an outdoor public square and a reoriented entrance facing The Goods Line walkway from Central station. 

The state government said the revitalisation will help host exclusive international exhibitions in addition to the Powerhouse's existing collection.

Accommodation will also be built for regional school children in NSW to visit the museum and participate in learning programs.

 

The heritage revitalisation will take up to three years to bring to life.(Supplied)

Additional consultation and feedback will also be sought to "rebuild a consensus on what this site could be", Mr Graham said.

Powerhouse Museum CEO Lisa Havilah said visitation in the past 12 months had increased by over 240 per cent after COVID impacts.

"This revitalisation will essentially enable us to grow our audiences even further," she said.

The Powerhouse Museum's Wran building opened in 1988, and will be preserved under the current plans.

The museum collective also includes Sydney Observatory in Millers Point, Powerhouse Castle Hill and Powerhouse Parramatta opening in 2025.