The extension to the Thames-side gallery is due to be
completed in 2012
Tate Modern has revised plans for its £215m extension - abandoning its original idea of a glass ziggurat.
The series of glass-covered cubes proposed for the world-famous gallery have been replaced with a pyramid-like structure clad in perforated brick.
The extension will rise from oil tanks in the former power station in central London. The tanks themselves will be used as spaces for art.
The new building is due to be completed in 2012.
It will be 65m (213ft) high and comprise of 11 levels.
The tanks will lead directly into the Turbine Hall and the interconnecting spaces will become the "foundation" of the new Tate Modern.
They will be used to show installations, displays, performances and film
Two new public spaces will be created - gardens and a southern square for commissions and performances.
The project is being drawn up by Herzog and de Meuron, the Swiss architects who transformed the former Bankside power station, which closed in 1981 and lay derelict for more than a decade until work began on creating Tate Modern, which opened in 2000.
To date, Tate has received £50m from the government, £7m from the London Development Agency and £13 million from the private sector towards its extension plans.
The gallery must now get planning permission from Southwark Council, which approved the original idea for the extension.