Competition Brief

Background and Challenge

The electrification programme, established in 2010 and significantly extended in the 2012 High Level Output Specification (HLOS), is one of the most significant railway investments in decades. UK government will invest around £9.4bn in a rolling electrification programme across the country.

Overhead electrification is a mature and well understood technology. However, it is believed that there is an opportunity to harness innovation as part of the electrification programme, to reduce costs in the overall investment programme, improve operating efficiencies and solve issues around the aesthetics of overhead line structures.

As part of the electrification programme, overhead line structures will need to be installed. For some parts of the network current overhead line structures may be considered 'ugly' and/or obtrusive in certain contexts in particular when passing through areas of outstanding natural beauty, conservation areas or residential areas. This is of particular importance for certain parts of the planned HS2 route for example the Colne Valley Viaduct.

A solution for this issue is an aesthetically pleasing overhead line structure design, which is more visibly appealing to line side neighbours. Historically, more aesthetic structures have cost significantly more to build and deploy because existing structures have been designed to specifically minimise the installation and deployment costs.

The design of current electrification structures is a complex issue but the general issues are outlined in EN 50119 2009+A1 2013 Electric traction overhead contact lines.

Technical Specification

Recent designs used in the UK for high speed rail have the following high level elements for the mechanical performance of a single track cantilever:

Approx. 220 - 250mm universal column
7 - 9 metres
Feeder wire:
Height varies between 6.30m and 8.40m and the conductor is 288mm ACSR. Can be mounted 'inboard' or 'outboard' depending on the surrounding environment (on a bridge/viaduct - inboard to stay within the bounds of the railway) and other conductors
Earth wire:
Aerial Earth Conductor (AEC) 93mm2 at 5.5m outside the mast as it would conflict with the cantilever on a standard mast.
Contact wire:
The contact wire is 150mm2 copper at a standard height of 5.08m with an along track regulated tension of 25-30kN.
Catenary wire:
Catenary Wire could be a 95mm2 bronze conductor with a regulated tension of 15.0-20kN. The system height would be 1.4m to 1.6m putting the catenary wire at 6.5m to 6.7m at the support.
-18 to +40
Location dependant often 35 m/s
Span length:
Maximum span would generally be 60m on tangent track decreasing as the track radius of curvature decreases. Nominally between 45-55m
Radial load:
Maximum 2.65 kN at contact wire height on a pull off cantilever in curved track.

Cross sectional diagrams of several structures can be downloaded below - UPDATED 20 January 2014

The Challenge

The challenge is therefore, to design Overhead Line Structures that are more aesthetically pleasing in the context of areas of the HS2 route which will impact on areas of natural beauty, conservation areas or residential areas and in particular viaducts and embankments. These designs should in principal be able to support the loads outlined in the technical specification above and if appropriate materials other than steel can be considered i.e. lighter and/or more sustainable.

The competition is open to architects, engineers, designers, single companies, organisations from private or public sector, or collaborations who will be capable of designing such structures.

The competition will run in two phases:

  • Stage 1 is intended to develop 1/10 scale models of the proposed designs to be set in the context of a specific area of the HS2 route. Contracts for this work will be for the duration of 5 weeks and up to £15,000 (inc VAT) per project.
  • Stage 2 contracts are intended to develop and evaluate successful designs from Stage 1. This stage will focus on but not be limited to the following areas of development:

    • design of end structures and 'turning' structures
    • how the design structure interfaces with the catenary system
    • modelling of forces and loads on the structure
    • construction and installation of structures

Developments will be 100% funded and suppliers for each project will be selected by an open competition process and retain the intellectual property rights (IPR) generated from the project, with certain rights of use retained by the EIT.

Whilst not absolutely necessary for the initial application, applicants should consider how they will deliver Stage 2 of the competition if they are successful.

In association with


Competition Contact

: 0113 203 1490

The competition is being administered by RIBA Competitions, to whom any enquiries relating to the general conditions of this competition should be addressed.