A new �30m glass-fronted “sustainable” conference centre in the Royal Docks will open to the public in September.

Siemens’s Crystal building will hold a spectacular gala event and light projection show.

Designed as a full electric building, the Crystal uses solar power, ground source heat pumps and energy-efficient LED lighting, and can operate free of fossil fuels.

The day after the September 24 opening date, it will host UN Habitat’s Urban Planning Conference.

It represents part of London Mayor Boris Johnson’s pledge to create thousands of jobs in the area in the years after the Olympics.

Mr Johnson said: “The Crystal is set to be a stunning new addition to London, generating jobs and furthering my ambition to regenerate a once neglected area of the capital.

“Not only this, but the flagship Siemens sustainability centre shows that this city has the clout to bring in world class businesses to invest in our future, in this case by promoting London’s status as a global hub of green innovation, technology and skills.”

The site will also contain electric vehicle recharging points and a cafe.

Roland Aurich, chief executive of Siemens plc and North West Europe added: “I am delighted we are now planning the launch events in September and I look forward to welcoming city decision makers from around the world as well as all our visitors to experience this unique new London landmark.”