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Royal Decree 1890/2008: Energy Efficiency for Outdoor Lighting Installations

On 1 April this year the Royal Decree 1890/2008 came into force, and its corresponding Complementary Technical Instructions. It was approved on 14 November 2008 by the Ministry of Industry, Tourism and Trade. This Royal Decree is mandatory and it is part of the Spanish Government’s 2008-2011 Energy Saving and Efficiency Plan, a strategy called E4 (2004-2012 Energy Saving and Efficiency Strategy) which establishes a series of standard actions aimed at improving the energy system in Spain.

The scope of application of this Royal Decree is national, but we have to take into account the different regulations in every autonomous community and apply the most restrictive one in each case. In Catalonia we find the regulation 82/2005 on Environmental Regulation of Lighting to protect the environment at night. This regulation covers the aspects relating to the zoning of Catalonia according to the protection of the land from light pollution; it establishes the characteristics of the installations and of the lighting devices according to the protection areas in which they are installed; and it regulates how lighting works according to the season, the time, maintenance, and adaptation of the existing light.

The main objectives of the Royal Decree are:

•    To improve energy saving and efficiency, and consequently, reduce greenhouse-effect gas emissions. Forecasts say that with the application of the new law, up to 30% of energy could be saved, without affecting the quality of the light. That percentage is very important if we take into account that in some cities about 50% of the energy consumed is used for public lighting.

•    To limit glare and light pollution. By pollution we mean the brightness in the night sky caused by reflection and diffusion of artificial light in the gas and air particles, because too much light and/or unsuitable luminaires are used. The bad use of this light involves unnecessary energy wasting on one hand, and on the other it affects some animals and prevents observatories from studying the sky.

•    To reduce intrusive or annoying light. The Royal Decree defines this kind of light as the one coming from outdoor lighting installations that produces discomfort, distraction or reduction of the ability to take in essential information, thus causing damaging effects on citizens who live in the area or pass by, and users of the transport systems. A clear example of this annoying light would be a streetlamp without a screen or filter in front of a house window.

The Royal Decree establishes technical conditions for the design, execution and maintenance, which outdoor lighting installations must comply with, both for public and private use, whenever they affect the street. The affected installations would be those of more than 1KW, whether they are new, with more than 50% of their power modified, or belonging to the amount of luminaires or adaptations of existing ones, whenever the Public Administration considers it necessary. The typologies of installations that the Royal Decree includes are those mentioned in the Low Voltage Electrotechnical Rules, which establish the safety conditions for outdoor lighting in the Technical Instructions ITC-BT 09 (roads, streets, squares, gardens, monuments…), ITC-BT 31 (swimming pools and decorative fountains) and ITC-BT 34 (temporary installations).

In order to reach the established objectives, the Royal Decree starts off by defining an energy classification for lighting installations, based on the following formula:


where S is the lit-up surface, Em is the average illuminance, taking into account the planned maintenance, and P is the total active power installed, that is, taking into account the consumption of lamps but also of the auxiliary equipment they require in order to be used.

If we compare the value obtained from the luminous calculation with a series of tables that we can find in the ITC-EA 01, we will have an energy classification for the installation that goes from A (highly efficient) to G (less efficient). We have to clarify that this classification is for the installation as a whole, not for the luminaire. This explains clearly that the aim of the Royal Decree is not only to guarantee a certain level of efficiency in the design of luminaires, but also to ensure that the light they emit follows certain efficiency criteria and only lights up what is necessary, and as much as needed.

Regarding technical lighting parameters like luminance (candela/m2), illuminance (lux) or minimum uniformity, the aim of the regulation is not to establish the minimum values for the different types of streets or spaces, because these are defined in the corresponding regulations, such as UNE EN 13201-1 on road lighting or UNE EN 12646-2 on lighting in outdoor work areas. The aim, however, is to establish a maximum limit that cannot be more than 20% of the values mentioned in the tables in the ITC-EA 02 of the current regulation. Other parameters (glare and lighting of the surrounding area, minimum luminance value in one point, etc.) are established only as reference values to be taken into account, but they are never a requirement in the project.

The energy characteristics of the lamps, luminaires and auxiliary equipment are also established. In the first case, lamps that do not meet a certain level of efficiency, 65 lumen/W, are excluded, in the case of street and ornamental lighting, thus prohibiting the use of mercury vapour lamps. These lamps were used quite a lot some years ago, especially for street lighting. It is currently believed that about a third of the roads in Europe still use this technology, which is not efficient and is very polluting. Therefore, the first step is to gradually replace installations that still use mercury vapour lamps and install high-pressure sodium vapour or metal halide lamps instead.

Auxiliary equipment will have a limit on the maximum amount of power consumed, according to the type of lamp and its power, as established in the ITC-EA 04. The values of fluorescent lamp equipment will also be adjusted to the value established in the RD 838/2002.

Regarding luminaires, they must comply with minimum requirements organised according to the type of lighting, and the flux they emit towards the upper hemisphere will also be limited, according to a classification of the area in which the installation is built, to prevent light pollution.

Based on the requirements described, the Royal Decree demands operational systems that turn on and off accurately at the established times, when the ambient light requires it. These devices can be photocells (only in installations with power under 5KW), astronomical clocks or more centralised adjustment systems that guarantee minimum values and flexibility according to specific conditions at every moment, with the aim of saving energy.

As we mentioned before, the Royal Decree refers to the design and the execution, but also to the maintenance of the energy efficiency of the installations, because these wear out over time, mainly because of the reduction of flux in the lamps and because dirt lodges in the lamps and luminaires. So, a maintenance plan has to be established, to guarantee that the energy efficiency studied in the project does not decrease in any case, by means of periodical checking and inspections.

Marta Culubret
Project Department Manager