The Royal Institute of British Architects, the Department of Energy and Climate Change and National Grid launched a competition in May to find a modern replacement for the traditional electricity pylon, the design of which has remained largely unchanged since the 1920s.

The competition attracted more than 250 designs from around the world. They were assessed on criteria including design quality, technical viability and public response.

The first design to make the shortlist was submitted by Ian Ritchie Architects, of London. Its F-shaped pylon won a similar competition in France in 1999. Named Silhouette, its UK design involved the work of Bath-based sculptor Ann Christopher and engineers Jane Wernick Associates.

Landscape architects Gustafson Porter made it into the final six with a little inspiration from nature. The London firm said its Flower Tower was "heavily influenced by organic shapes, such as birds in flight and the gently curving forms of flowers and plant life".

The shortlisted submission from London's Amanda Levete Architects, with engineers Arup, was designed to respond to changes in topography. The pylon's size and profile could be altered to suit the terrain, it said.

Knight Architects, of Buckinghamshire, promised to reduce "visual clutter" through significant reductions in tower height with its shortlisted Y-shaped design. This is thanks to its use of modern insulating materials within the design, which involved work from Irish engineers Roughan & O'Donovan, and ESB international.

New Town Studio, based in Essex, said it used the "lattice" frame of the traditional pylon as its inspiration when creating this shortlisted design with London engineers Structure Workshop. It was said to allow the passer-by to look through, rather than at, the pylon.

But it was Danish architects and engineers Bystrup who scooped the £5,000 top prize for the T-Pylon, billed as a "no-nonsense" structure which, it says, can be painted to suit the surrounding landscape.

Designs taking the human form were highly commended in a recent competition in Iceland but humanoid or animal shapes failed to win over the UK judges, who included Energy Secretary Chris Huhne, leading architects and senior National Grid executives.