The centre is planned for Wroughton near Swindon, where the NMSI owns the 545-acre airfield site on which it stores and conserves 20,000 objects.

The new centre will be a sustainable building housing about 500,000 objects from the Science Museum and other national museum collections. All will be accessible to the public with paid-for tours using the collections to explain sustainable development.

A decision on planning permission for the £80m centre is expected early next year and construction should start in 2007 with completion in 2009.

Steve Briggs, the head of planning and community engagement at the NMSI, said the centre is to be an environmental, climate-controlled, grass-roofed building. He said the construction and running costs will be 'extremely low' at £65,000 a year.

The NMSI will fund the project with public and private money. Applications for funding have already been made to government, the South West Regional Development Agency, the Heritage Lottery Fund, the Big Lottery Fund and private companies.

Briggs said because of the reduced costs involved, he was hopeful for funds from the Department for Culture, Media and Sport. 'Our sponsoring body seems to be keen on the project because it helps it with savings.'

Blythe House, the existing collections store in Olympia, which the Science Museum shares with the British Museum and the Victoria and Albert Museum, is to be sold and the money will be reinvested into the project.

The centre is the first phase of developments for NMSI Wroughton. Further initiatives on the Wroughton site include a living village with
residential sustainable housing and
a conference and study centre.

These wider developments have been in discussion for more than five years. A source said previous ideas for the project were approached as an 'all or nothing big bang'. But the source said the new paired-down plans were still ambitious.

A museum commentator said: 'The NMSI's instinct is absolutely correct to work towards sustainable development for the future.'

Felicity Heywood