Retrofitting outdoor lighting: international and national status and targets

October 2021

Agence pour l’Environnement et la Maîtrise de l’Energie (ADEME)

The subject of many economic, political and environmental issues, outdoor lighting, and in particular its management in public spaces, is now a skill in its own right. For the past fifteen years, the price of electricity has been rising steadily, putting a strain on local authorities’ budgets, which amount to 1 billion euros per year in France. With an ageing and energy-intensive lighting stock, the territories have been addressing the issue for several years in order to limit consumption and therefore energy expenditure. Some have implemented coherent and ambitious renovation programmes on their own or on an inter-municipal scale. Despite the 500 million euros of annual investments made by local authorities to renew and modernise their public lighting systems, consumption remains high and the efforts made must be increased. Public lighting is now at the heart of the expectations of citizens, who are increasingly concerned about the way in which the city is administered, but also increasingly involved in environmental protection. Public lighting is a source of light pollution that contributes to the fragmentation of natural habitats. Intelligent management of lighting is therefore essential. The technological tools for this management already exist.

In addition, new needs are emerging in our territories: video protection, wifi terminals, electric vehicle charging stations, etc. Lighting infrastructures are increasingly in demand and should eventually become one of the means of pooling equipment for these new needs.

This is why it is becoming urgent to accelerate the renovation of the network and to make it communicative with a view to the development and planning of future intelligent territories. Public lighting is one of the major players in the ecological transition and a lever for action to limit light pollution and energy consumption. This guide published by ADEME should enable readers to gain a better understanding of public lighting, to better understand the issues at stake and to become involved in its transformation.

To download : ademe-eclairage-exterieur-2021.pdf (3.9 MiB)

1 - state of play

Outdoor lighting includes both private and public installations. It is to the latter that this report relates. Public lighting represents all the lighting resources used to promote the safety of travel, people and property, the comfort of users and the enhancement of public spaces. Although most public lighting is managed by the public authorities, according to the Court of Auditors’ report of 2021, 30% of municipalities have transferred this responsibility (investment and/or operation) to a group of municipalities or to a local energy syndicate. The stakes are high since public lighting is the second largest energy consumption item for municipalities after buildings, accounting for 12% of consumption and 18% of energy costs. This represents 32% of the electricity consumption of municipalities in mainland France for 31% of electricity expenditure, and 46% and 38% respectively for municipalities in overseas France.

There are approximately 30 light points per kilometre of roadway lit (constantly decreasing over the last fifteen years) and approximately 160 light points per 1,000 inhabitants. The number of light points per kilometre of roadway is obviously lower in small towns than in large cities. Conversely, the number of kilometres of roadway lit per 1,000 inhabitants is higher in small towns, due to the lower density of housing. Public lighting represents a potential energy saving for communities and consequently for citizens, estimated at between 50 and 80%.

A. An obsolete stock

Too many installed luminaires are more than 25 years old and only 3 to 5% are replaced each year, which means that at this rate it would take between 20 and 30 years to renew the entire stock, estimated at 11 million light points with several light source technologies. The lamps used vary little according to the size of the municipality, with sodium lamps still in the majority everywhere.

Metal halide (or iodide) lamps are mainly used in large municipalities (19% of lamps in municipalities with more than 50,000 inhabitants and 4% of lamps in small municipalities). In contrast, small municipalities make more use of LEDs and it is in these municipalities that mercury vapour lamps are still found. Sodium lamps, which appeared in the 1950s, account for 57% of the current stock. They can be recognised by their orange light. In the 1970s, high pressure sodium (HPS) lamps gradually replaced low pressure sodium lamps. Mercury vapour lamps (or fluorescent balloons), which emit a white light and are considered to be energy consuming, still account for 8% of the stock. They were banned from the European market in 2015 but are still present in the installed base. Finally, metal halide (or iodide) lamps (which appeared in the 1990s) generally produce white light and now account for around 5% of the installed base. LEDs (light-emitting diodes installed in the last 15 years) now account for about 20% of the installed base. The remainder (10%) consists mainly of fluorescent tubes and compact fluorescent lamps.

B. Duration of use of lighting

In 2017, public lighting represented a power demand of 1,260 MW, or about one nuclear power plant unit. Consumption is estimated at 4.7 TWh per year. The average power of a light source is 145 W excluding ballast, with fairly large variations depending on the size of the municipality. A light point costs an average of €50 per year in electricity consumption. The number of hours of use of public lighting fell from 3,305 hours in 2012 to 2,818 hours in 2017. This is the number of hours at full power equivalent (for operation at 50% reduced power for 6 hours, 3 hours are counted).

Almost 40% of municipalities in metropolitan France switch off their public lighting for part of the night and 8% vary the intensity of the lighting. Smaller municipalities are more likely to switch off their street lighting completely in the middle of the night, while larger municipalities are more likely to reduce the intensity: - 43% of municipalities with fewer than 2,000 inhabitants switch off their street lighting, compared with only 7% of municipalities with more than 50,000 inhabitants; - 6% of small municipalities use dimming, compared with 19% of large municipalities. It can be deduced from this that the latter are more equipped with management systems. In 2015, a survey showed that residents wanted to be consulted before their mayor decided to switch off the street lighting in their municipality, as they believe that good street lighting makes a municipality more attractive and dynamic. The majority, especially in cities, felt that switching off street lighting was not the best way to save energy because street lighting plays an important role in their safety.

C. Energy saving opportunities

Replacing old technology equipment can generate significant savings on local authority bills and reduce energy and maintenance costs by a factor of 4 to 5 if intelligent automatic switching and dimming systems are used with the replaced luminaires. In concrete terms, according to the FNCCR, Serce and the Syndicat de l’éclairage, if we were to replace the following with high-performance luminaires - the one million luminaires designed for mercury vapour lamps that still remain in the installed base, the annual energy savings are estimated at 350 million kWh, i.e. 22,470 tonnes of CO2 equivalent emissions avoided; for an investment budget estimated at 1.5 billion euros, a payback time of between 4 and 6 years would be obtained; - For the 2.5 million luminaires with a power of 250 W or more still in service, the annual savings would amount to 1,600 million kWh, or 102,720 tonnes of CO2; for an estimated investment budget of €4 billion, the payback would be between 3 and 5 years. Savings and payback times are estimated for equal lighting durations. With the implementation of automatic lighting, dimming and extinguishing systems, the results would be improved by an average of 20 to 30%.

2 - international and national objectives

The Kyoto Protocol was signed on 11 December 1997. 196 Parties (195 States and the European Union) have ratified it. The first period of this protocol only really committed 37 industrialised countries. The United States, the largest emitter of greenhouse gases at the time, signed the Protocol but has still not (as of 2021) ratified it. The countries committed to the Kyoto Protocol agreed to reduce their greenhouse gas emissions by at least 5% over the period 2008-2012 compared to 1990 levels. They have collectively met this target (with a reduction of more than 20%). A second commitment period for the Protocol was set at the Doha Summit in December 2012 and runs from 1 January 2013 to 31 December 2020. On 12 December 2015, at COP21 in Paris, Parties to the UNFCCC (United Nations Framework Convention on Climate Change) reached an agreement to combat climate change and to accelerate and scale up the actions and investments needed for a sustainable low-carbon future. The objective of the Paris Agreement is to strengthen the global response to the threat of climate change by keeping the global temperature increase well below 2° Celsius above pre-industrial levels and to continue efforts to further limit the temperature increase to 1.5° Celsius. The Paris Agreement entered into force on 4 November 2016. The Paris Agreement regime took over from the second period of the Kyoto Protocol on 1 January 2021, for an indefinite period.

A. Europe: the Green New Deal for Europe

The Green New Deal for Europe aims to provide the EU institutions with an economic, technical and legal framework for making major investments in strategic infrastructure and economic activities that have a significant impact on tackling climate change and managing its consequences. The Green New Deal proposes solutions to ensure that these investments have a significant and real impact on employment, health, safety, education, cost of living, social justice, public services, etc. Following the European Council’s agreement on a reduction of at least 55% in greenhouse gas emissions by 2030 compared to 1990 levels, the EU and the 27 EU Member States formally presented this target as their new nationally determined contribution (NDC).

Under the Paris Agreement, every five years each country must present the measures it plans to put in place to reduce its national emissions and adapt to the effects of climate change. For the European Union, this new NDC should serve « as an example in encouraging our international partners to increase their NDCs ahead of COP26 in Glasgow [in November 2021]".

B. The National Low Carbon Strategy (NLCS)

The national low-carbon strategy has been adopted by the government (decree on national carbon budgets and the national low-carbon strategy, Book II, Title II, Chapter II, Section 1 of the Environmental Code). The SNBC describes France’s roadmap for conducting climate change mitigation policy. It provides guidelines for implementing the transition to a low-carbon economy in all sectors of activity. It defines short- and medium-term greenhouse gas emission reduction targets for France - carbon budgets - and has two ambitions: to achieve carbon neutrality, i.e. zero net emissions by 2050 (an objective introduced by the July 2017 Climate Plan and enshrined in law), and to reduce the carbon footprint of the French. The following are specifically concerned by the consideration of the national low-carbon strategy


To go further

bibliography (french)

  • Dépenses énergétiques des collectivités locales, ADEME, Caisse des Dépôts, FNCCR, AITF, CEP. 2019.

  • Guide de l’élu local et intercommunal. Éclairage public. FNCCR. 2021.

  • Publications de l’Association française de l’éclairage relatives à l’éclairage extérieur.

  • Trame noire - Méthodes d’élaboration et outils pour sa mise en œuvre, par Romain Sordello, Fabien Paquier et Aurélien Daloz. Publié par l’Office français de la biodiversité, mars 2021.

  • Annexe SSL : Solid State Lighting, Association internationale de l’énergie.

  • Les défis de l’éclairage public, par Roger Narboni, Concepto, et Fanny Guerard, responsable éclairage public, smart city et environnement, ville d’Asnières-sur-Seine. Territorial Éditions. 2021.