New Street Station will be able to handle 300,000 passengers a day - more than double its existing capacity - following a £500 million refurbishment to end an era of overcrowded platforms.

Officials behind the prestige project say the spacious new-look station will have the capacity to deal with 150 per cent more customers at peak times than is possible at the moment.

The partnership behind the scheme - Network Rail, Advantage West Midlands, Centro-PTA and Birmingham City Council - yesterday submitted an application for outline planning permission.

A decision by the city planning committee is expected before the end of the year.

The proposals for New Street Gateway include a shopping "street" through the centre of the station, making it easier for pedestrians to walk from the Mailbox to the Bullring.

Other improvements include:

*Two new public open spaces, at the junction of Hill Street and Station Street and at the St Martin's Circus entrance to the station;

* An atrium with a roof constructed from the same material used on the Eden Project, allowing natural light to flood into the concourse, transforming the environment for passengers;

* Up to £200 million of private sector investment to the south of the station, creating new commercial space and generating 3,000 jobs.

Martin Chambers, New Street Gateway project manager, said increased passenger capacity meant the completed station would be able to handle additional services flowing from possible changes to the franchise of the cross country line.

West Midlands business leaders raised fears earlier this week that the franchise changes would cause even more overcrowding on platforms which are already so congested that the station entrances sometimes have to be closed.

Mr Chambers said: "We are talking about creating a far larger concourse. The new station will be able to deal with many more passengers than is the case at the moment.

"Some people using the cross city line may have to change trains at New Street in future, but they will be able to do so in comfort."

Passengers are being promised an airport-type experience, browsing in concourse shops before boarding their trains via three sets of escalators for each platform.

Construction work will begin in early 2008, if planning permission is granted and applications for Government funding are successful.

The project will be undertaken in two phases enabling the station to continue to operate throughout construction.

The first phase will be finished by early 2011 and the completed station will be ready by 2013.

Mr Chambers added: "With everyone working together we have a once-in-a-lifetime opportunity to deliver a station that Birmingham can be proud of.

"The submission of the outline planning application brings with it further confidence that the planned start of site work in early 2008 will be achieved.

"Network Rail and its partners are absolutely committed to ensuring that this project starts on site as soon as possible, and that disruption for passengers is kept to a minimum."

Birmingham City Council leader Mike Whitby said: "The size and scale of this project is immense. Those who have any doubts about the ambition of this city only need to look at the plans that we are proposing."