Invest to Save – Changing to LED Street Lighting on London’s (TfL) Road Network

Context of Transport Climate Action

Transport for London (TfL) announced in late 2013 its intention to update the street lights on the TfL Road Network (TLRN) to LED by 2016, complete with a Central Management System (CMS). Approximately 14,600 will be updated by 2016 and another 20,000+ by the end of the current Business Plan period (2022/23).

  • TfL agreed a new energy efficient lighting programme to help reduce the cost of lighting the TfL Road Network (TLRN), while also doing its part to reduce CO2 emissions across the capital.
  • It is one of the largest ‘invest to save’ strategic road lighting projects ever undertaken in the UK, which will see improved reliability and lower operating costs all contributing to better and safer roads.
  •  Previously, the capital costs of LED technology were prohibitive except for use in particular locations such as tunnels and subways.  But as the LED market has expanded and matured, the business and technology case is now proven, increasing benefits by making such a large-scale update more viable.
  •  These improvements form part of the wider work TfL is carrying out across London to deliver the recommendations of the Mayor’s Roads Task Force (RTF) to tackle the challenges facing London’s streets and roads. The Roads Task Force (RTF) was set up by the Mayor of London in 2012 to tackle the challenges facing London’s streets and roads.


TfL is responsible for street lighting on the TfL Road Network (TLRN), which comprises routes of strategic importance such as trunk roads as well as specific street lighting on a small number of remote or segregated footways.

TfL provides street lights to:

  • Reduce the number/severity of accidents at night,
  • Reduce crime and the fear of crime,
  • Facilitate the safe and reliable transport of all road users on the TLRN.

As part of a trial, TfL replaced current streetlight luminaires in selected locations with LED lighting. By introducing LED lighting, TfL hopes to:

  • Reduce energy costs,
  • Reduce maintenance costs,
  • Reduce CO2 emissions,
  • Reduce sky glow and night time pollution
  • Reduce disruption to the network


The programme comprises of two specific strands:

  1. Introducing a Central Management System (CMS) for street lighting on the TLRN. This will allow TfL to remotely monitor and manage street lighting and dynamically control levels of lighting depending on use. By adjusting the lighting levels to be aligned better with traffic flows and road usage at different times of night, TfL will significantly reduce its energy consumption and carbon emissions, without compromising road user safety or security – it is a TfL requirement that road lighting on the TLRN conforms to the appropriate British Standards. The system will remotely record lighting failures, enabling maintenance crews to ensure that any fault repairs are better managed.
  2. Replacing conventional lighting with Light Emitting Diodes (LED). This will eventually see 35,000 street lights updated through both targeted investment and TfL’s regular streetlight maintenance by 2022/23. The new LED technology will be rolled out across the majority of TfL street lights during the next ten years. The total cost of implementing the CMS and the roll out of LED technology is approximately £10.9m. The pay back time is estimated to be under 10 years.


  • Across London, TfL has some 52,000 street lights, and as part of the Mayor’s pledge to cut CO2 emissions, TfL has begun implementing the Energy Saving Plan which will be delivered initially over three years, but which will continue over the period of the Business Plan.
  • By 2016, the programme aims to reduce associated CO2 by around 6,700 tonnes a year and contribute towards approximately £1.67m of savings for TfL a year.
  • The roll out of new LED technology will reduce energy consumption by more than 50% over the latest Business Period from 34.2m kWh to 15.7kWH.
  • Quantified Analysis has shown that the scheme would become financially positive after 7 years (i.e. 2020-2021)

Potential for scaling up

  • Most, if not all of the remaining 17,000 street lights on the TLRN to be updated within 10 years.
  • Central Management Systems have been set up in several London Boroughs. These, together with the TLRN CMS, could form the basis for other cities to consider this approach.

Selected references



London, UK






UK, Mitigation, Technology, Passenger, Freight


Transport for London (TfL)


Sam Longman Policy Manager for Environment Strategy and Planning, TfL