LED public lighting: current regulations, technical requirements and key points for compliance

LED public lighting has its own regulatory framework in Spain. There are regulations, technical standards and parameters that every outdoor lighting installation must comply with.

This applies both to new works and to the refurbishment of existing networks. This article brings together the basic requirements so that engineers, installers and municipal managers can prepare their projects properly. That way, they won't have to spend hours searching through the BOE (the Spanish Official State Gazette).

Regulatory framework for outdoor lighting in Spain

The outdoor lighting sector in Spain operates under a well-established regulatory framework, although it includes several layers worth distinguishing.

Regulations on Energy Efficiency in Outdoor Lighting RD 1890/2008

Royal Decree 1890/2008 is the main reference for any public lighting installation in Spain. It approves the Regulations on Energy Efficiency in Outdoor Lighting (REEAE) and its supplementary technical instructions (ITC-EA). It sets out the limits on installed power, the permitted energy efficiency indices and the requirements for grading the installation.

This regulation requires every new installation or substantial refurbishment to demonstrate its energy grade through an energy efficiency index (IEA). The minimum value required depends on the type of road and the lighting level designed. Alongside RD 1890/2008, sector regulations require compliance with the REBT regulations in everything related to the power supply, wiring and electrical protections of the lighting points.

The Spanish public lighting decree also covers requirements for flow reduction programmable by schedule. Installations must be able to reduce the luminous flux during off-peak hours, which means fitting flow regulators or telemanagement systems. A twilight sensor with automatic dimming can meet this requirement quite simply on small installations, although more complex projects call for centralised systems.

UNE EN 13201 standard road lighting classes

The UNE EN 13201 standard is the European technical reference for classifying roads according to their lighting needs. It defines the M (motorised traffic carriageways), C (conflict zones and junctions) and P (pedestrian routes) classes. The road lighting class M, C or P assigned to each stretch determines the minimum luminance, illuminance and uniformity values that the installation must achieve.

Selecting the right class depends on the analysis of the design speed, traffic volume, presence of pedestrians and type of surroundings. This classification is the first step in any outdoor lighting project.

Technical parameters that a public lighting installation must meet

Once the road class has been defined, the project must show that the calculated values meet the regulatory thresholds.

Illuminance and luminance levels by road type

The luminance level on the carriageway varies according to the assigned M class. The table below shows the reference values according to UNE EN 13201 for the most common classes:

The calculation relies on the installed power W/m² as an energy control parameter and on the spacing between lighting points. This has a direct bearing on the uniformity achieved. Excessive spacing between luminaires causes drops in illuminance that breach the uniformity thresholds, even when the installed power is sufficient.

Uniformity factor and glare

The uniformity factor is as demanding as the average luminance value. An installation that reaches the correct average luminance but with an uneven distribution does not comply with the standard. The threshold increment (TI) controls the disturbing effect on drivers and is capped at values between 10% and 20% depending on the class.

Upward light output ratio ULR

The upward light output ratio (ULR) measures what percentage of the luminaire's total luminous flux is emitted towards the sky. Spanish regulations set maximum limits according to the zone of protection against light pollution. In E1 zones the ULR must be 0%; in E2 zones, up to 0.5%; in E3 and E4 zones, somewhat higher values but still kept low.

LED luminaires with full cut-off optics meet these requirements without difficulty. It is one of the strongest technical arguments in favour of LED technology over high-pressure sodium when refurbishing a network.

Requirements for public lighting luminaires

The installation parameters are met or not depending on the characteristics of the luminaires themselves. There are three attributes that the technical specifications of any tender must require.

Required IP and IK protection ratings

The most common IP and IK ratings on LED street lights on public roads are IP66 and IK08 or IK10. IP66 is the minimum in most urban installations. Areas with a risk of vandalism or impact may call for IK10.

Recommended colour temperature for public roads

The colour temperature for public lighting does not have a single fixed value. However, RD 1890/2008 and sector recommendations place the optimum range between 3,000 K and 4,000 K.

Values below 3,000 K are suitable in residential settings or areas with greater protection requirements against light pollution. Above 5,000 K, the blue light increases the apparent ULR. It can also affect wildlife and people's rest in residential areas.

• The minimum colour rendering index Ra for public roads is Ra ≥ 60.
• In pedestrian shopping or security areas, Ra ≥ 70 is recommended.
• This makes it easier to recognise people and objects.

Minimum efficiency in lm/W according to the regulations

The IEA for efficient outdoor lighting requires that the luminaire-equipment set exceeds a minimum efficiency. Current quality luminaires for public roads must exceed 100 lm/W as a finished product. RD 1890/2008 sets minimum energy efficiency indices by sections. Tender specifications require values between 110 and 140 lm/W to guarantee the energy efficiency of municipal lighting throughout the product's service life.

The maintenance factor and lumen depreciation is another mandatory parameter in the project. The luminaire must keep at least 80% of its initial flux (LLMF ≥ 0.80) at 25,000 hours of operation. The depreciation factor of the assembly (MF) must include both the LED depreciation and the dirt build-up on the optics.

CE and RoHS certification is an essential requirement for any luminaire installed on the public network. Without CE marking, the luminaire cannot be included in a stamped project or in a public tender.

Light pollution zones E1 E2 E3 E4

Light pollution is regulated in Spain mainly through RD 1890/2008 and the complementary regional legislation. Installations are classified according to the environmental zone: E1, E2, E3 and E4.

Each zone has limits on ULR, maximum façade luminance and light obstruction values. A project that fails to correctly identify the applicable E zone runs the risk of not passing the technical inspection of the outdoor lighting after execution.

Audit and energy certification of lighting installations

The LED public lighting audit is not a minor administrative formality. It is the mechanism by which the owner of the installation demonstrates that it meets the energy efficiency indices required. Where appropriate, it also identifies the improvements needed.

The process includes the inventory of lighting points. It also includes the measurement of illuminance levels in the field. In addition, it includes the calculation of the resulting energy grade of the lighting. Finally, it includes the comparison against the thresholds set by RD 1890/2008.

For installations of more than 5,000 lighting points, a periodic audit is mandatory. The result determines the public grants available for network refurbishment, so it makes sense to carry it out rigorously even when not strictly required.

The technical requirements for LED street lights on public roads must be documented in the project file:

• Include the nominal power and the initial flux.
• State the maintenance factor.
• Add the photometric data, in LDT or IES file format.
• Also attach the product certificates.

How to find out whether your current installation meets the regulations

The regulations on LED public lighting in Spain do not require all installations to be refurbished straight away. They do state that any substantial refurbishment must leave the network in compliance with the REEAE. The first step in finding out is to cross-check the network inventory against the energy efficiency indices calculated according to the technical instructions of RD 1890/2008.

If the network has high-pressure sodium or mercury vapour luminaires, failure to meet the efficiency thresholds is almost a certainty. Refurbishing with LED technology improves energy efficiency, the uniformity factor, the ULR and the service life. It also cuts maintenance costs in the medium term.

At Ibérica de Iluminación we have a complete range of LED street lights for public roads. They meet the technical and certification requirements set by Spanish regulations. If you need technical advice for your project or tender, get in touch with our team.

Frequently asked questions about LED public lighting

Which regulations govern public lighting in Spain?

Royal Decree 1890/2008, which approves the Regulations on Energy Efficiency in Outdoor Lighting, is the main piece of legislation. It is supplemented by the UNE EN 13201 standard for road classification and by regional legislation on light pollution.

How many lux should a residential street have?

It depends on the lighting class assigned. A low-speed residential road corresponds to classes M5 or M6, or to class P3 in pedestrian areas, with a minimum of 5 horizontal lux.

What do the lighting classes M4 or M5 mean?

They are categories from the UNE EN 13201 standard that set the minimum luminance and uniformity levels required on the carriageway. M4 corresponds to moderate-traffic roads with an average luminance ≥ 0.75 cd/m², and M5 to low-traffic roads with an average luminance ≥ 0.5 cd/m².

What is the upward light output ratio and why does it matter?

The upward light output ratio (ULR) is the proportion of the luminaire's luminous flux that is emitted upwards, towards the sky. Its regulatory limit aims to reduce light pollution. In E1 and E2 zones it must be practically zero.

Do modern LED street lights comply with light pollution regulations?

Generally yes, provided they have full cut-off or semi cut-off optics and a colour temperature below 4,000 K. The ULR has to be checked in the manufacturer's photometric documentation.

Is an energy audit of outdoor lighting mandatory?

For installations of more than 5,000 lighting points, a periodic LED public lighting audit is mandatory under RD 1890/2008. For smaller installations it is not legally mandatory on a periodic basis, but it is necessary when applying for subsidies or undertaking a substantial refurbishment.

What happens if my municipality's lighting does not meet the regulations?

The municipality may face requirements from the regional or central administration and, in the event of a refurbishment, will be obliged to bring the installation into line with the REEAE. In addition, a non-compliant network tends to lose access to public funding lines for lighting refurbishment.