CPG Newsletter: Energy-efficient Street Lighting

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Energy-efficient Street Lighting 

Why choose street lighting to conserve energy?

Street lighting is essential to road safety and to meeting the needs of residents, pedestrians, cyclists and drivers. Why, then, should we aim to conserve energy here? Are there not better suited sectors?

In order to meet its climate targets for the German Federal Government, opportunities for energy savings must be found in all areas of society. The question is not why lower energy use in street lighting but how great is the savings potential and which strategies are worthwhile.

Germany’s some 11,400 urban and rural municipalities contain roughly 9.4 million street lights, each operating 4,000 hours per year on average. The enormity of the energy consumed for public outdoor lighting is easy to underestimate. In fact, it makes up around 40% of municipal energy use in Germany. The newest lighting technology consumes considerably less energy than older systems. If all of Germany’s street lights used today’s advanced bulbs, energy consumption would decrease by 80%. Very few sectors in Germany have such a high energy savings potential.

Such energy savings would significantly cut electricity costs for urban and rural municipalities. According to the German Electrical and Electronic Manufacturers' Association (ZVEI), more efficient lighting technology could save 2.2 billion kWh of energy and reduce CO2 emissions by 1.4 million tons. The accompanying savings in electricity costs are estimated to be around 400 million euros (assuming a price of 0.18 euro per kWh). Although such savings are enticing, they require large initial investments and new technologies sometimes bring with them higher maintenance costs. Before a municipality decides to invest in new lighting technology, it must assess all the costs of restructuring: planning, lighting design, purchasing, electricity, maintenance, disassembly, and disposal. The information in this newsletter is meant to help local administrations make such decisions.

Figure 1: Implementing such energy-saving measures may involve different parts of the lighting, whose correct technical name is given in Figure 1.

At first glance, it might seem easiest just to replace existing bulbs with new ones. But retrofit bulbs are not always compatible with existing systems and even when they are, they can exert excessive mechanical strain on sockets because of their extra weight. What’s more, many give off less light than conventional bulbs. The alternative is to install entirely new lighting systems, but this is in most cases very costly. It requires not only new infrastructure but also special lighting design to optimise the unique beam characteristics of advanced lightbulbs.

Light-emitting Diode (LED) Technology

In 2008, after what now appears to be small successes, LED technology innovation took a rapid turn and fundamentally changed the lighting industry. LEDs, first developed into commercial products in 1962, were expensive and only produced red light. White light LEDs could only be manufactured after the introduction of blue light LEDs in 1996. LED manufacturing costs are now low enough that nearly all sectors use them including in urban lighting. This ten minute video [available only in German], by VDI ZRE offers a brief insight into LED technology and lists the advantages of installing them indoors.
Nowadays there are a variety of different LED technologies available: the most widespread are inorganic LEDs and organic LEDs (OLED). Any mention of LEDs in this newsletter refers to inorganic LEDs, unless otherwise specified. 

The LED chip is the core component in an LED module. Built into the structure of the LEDs, the chips are usually about one millimetre edge to edge and made up of semiconductor crystals. When exposed to an electrical current the semiconductor crystal produces light – a process called electroluminescence – and heat. The components of the LED module are depicted in Figure 2. Reflectors inside the LED position the angle of the beam to be between 15 and 180 degrees. If a lens is installed then this will both protect the chip and redirect the light. An important element for a long operating life in an LED is its cooling system. If an LED is not cooled properly then this will significantly decrease its longevity and lower its light current. 

Figure 2: Left: Cross section diagram of an LED-module and its components. Right: Energy flow
Over the past five years, LED sales have increased even more rapidly than projected. During the first quarter of 2015 every second outdoor light sold in the commercial, industrial and municipal sectors was an LED. But industry standards haven’t been unable to keep up with this rapid rise in demand, and there’s now a pressing need for uniform labelling and test criteria.

The EG Directive No 245/2009, which regulates the minimum levels of illumination, restricts alternative options for modern street lighting technologies. Nowhere does it assert an obligatory modernisation of lights, but it does state that bulbs which do not meet necessary illumination requirements are no longer permissible. Furthermore, the amended version of the RoHS Guidelines (Restriction of the use of certain Hazardous Substances) which regulates the levels of harmful substances such as quicksilver, lead, cadmium allowed in lamps, also limits potential commercial options. Due to the fact that LED retrofits are not always technically feasible in existing lighting, legislators may introduce stricter regulations requiring that municipalities replace their entire street lighting before scheduled. Such regulation could place undue financial burden on municipalities especially if existing investments have yet to amortize completely. 

To find out more about the future of EU regulations on light sources see the Federal Environment Agency webpage on the EU Regulation on Lighting Open Forum.

Chances and Pitfalls for LED Outdoor lighting

One of the biggest selling points for LEDs is their low energy consumption. LEDs, compared to some conventional outdoor lighting systems, as shown in Figure 3, save up to 80% of energy use and reduce accompanying CO2 emissions. Another selling point of LEDs is their long operating life. LED street lights, according to the manufacturers, can operate between 50,000 and 100,000 hours – a large advantage compared to conventional lighting technologies, which usually operate between 1,000 and 30,000 hours. This puts LED outdoor lighting systems in operation for more than a decade. 

Figure 3: Comparison of energy consumption saving potential in different outdoor lighting systems

So far, the experiences of some municipalities with LED lighting are not as successful as their modern technology suggests. Although significant progress has been made, these negative reports are partly due to the fact that LED technology is still a relatively new technology and has not been fully expanded to deliver on a wider scale.

The predicted operating life of an LED is around 100,000 hours – eleven years of continuous use. Because of this, manufacturers haven’t been able to carry out tests lasting that long before releasing their products onto the market. Their operating life calculations are therefore based on test predictions. Another factor that could shorten the operating life of LED modules is their higher susceptibility to damage in certain areas than conventional bulbs. Regardless of the lighting system, however, both lightning and switching surges can cause large power failures. Besides power quality issues, ineffective cooling in an LED – stemming from manufacturing flaws or dirt build-up – further decreases operating life. What’s more, the LED module is made up of a variety of components which, at times, have a shorter operating life than the LED itself. Municipalities must include this factor when planning to use LED-modules for street lighting so to avoid untimely disruptions that could result in high costs. After a number of years crucial parts for LED modules cannot be replaced because manufacturers discontinue production and replace them with newer ones. 

LEDs do have their advantages, however. They are extremely resistant to wear from switching on and off and can be easily dimmed. This provides additional opportunities for energy savings. A needs-based low-energy operation is easier with LEDs than with conventional technology, without the reduced lighting creating unsafe areas. Currently only 2% of all lights use smart control. A 2010 report by McKinsey describes the vast potential of LED smart technology for energy savings technology.

LEDs have other advantages as well. The light produced by LEDs is less attractive to insects and birds and thus less disruptive to their natural rhythms. Moreover, the LED light beams can be easily directed away from, say, gardens and houses to reduce light pollution for local residents, as shown in Figure 4. This kind of improvement is possible with other technologies too, but the construction of LED lights makes them particularly well-suited. The targeted use of reflectors in LED lights not only decreases unwanted light; it also improves visibility in areas that need it.

Figure 4: Depiction of lights with and without reflector technology 

Many claim that outdoor LEDs are cheaper than incandescent lights because of their virtually non-existent maintenance costs and long operating life. But numerous municipalities have reported otherwise. Indeed, they have found that the introduction of modern lighting technology has increased their expenses. This is primarily due to labour costs: the German Electrical and Electronic Manufacturers' Association (ZVEI) recommends that only experts install LED systems, and the process of replacing individual parts in modern lights and LED modules is very time consuming. Some municipalities have found it more cost-effective to replace entire lights than to buy replacement parts, as the former requires less labour. But this is a wasteful use of resources, and an undesirable consequence of modernisation.

Manufacturers do not plan to produce LED lights with replaceable modules on the grounds that their long operating life obviates the need. Moreover, they argue, non-replaceable modules offer better design leeway for heat dissipation and surge protection. But the biggest argument against replaceable modules concerns their long-term upkeep. As it stands now, the international standards for replaceable LEDs proposed by the industrial consortium ZHAGA have yet to receive widespread acceptance. Were replaceable LEDs produced today, it is likely that compatible replacement parts would vanish from the market to make way for new technology before the end of the lights’ operating life.

Financial Incentives and Subsidiaries 

In order for municipalities to equip their street lights with the newest technologies, some will have to replace their entire system, including the light poles. But this requires an enormous amount of labour, so much that many municipalities wouldn’t be able to afford it even were their investments to amortize within a decade. As a result, many decide against modern lighting systems. 

Financial incentives and low-interest loans exist to support the replacement of street lighting because without them costs would simply be too high. What’s more, they promote responsible environmentally friendly action helping Germany meet its climate goals. Pilot projects, though costly, introduce new technologies that are crucial for testing efficient solutions. To promote pilot projects, the Federal Ministry for the Environment, the Federal Environmental Agency, and the KfW Development Bank introduced the Federal Competition for Energy Efficient Street Lighting as part of the German government’s Environmental Innovation Program (UIP).

This 30-minute video called The Federal Competition for Energy Efficient Street Lighting from 2014 [available only in German] summarises measures undertaken by participants and details a selection of the winning projects. A list of all the competition winners can be found on the homepage of the The Environmental Innovation Program (UIP). 

Today, as part of the 2008 `Richtlinie zur Förderung von Klimaschutzprojekten in sozialen, kulturellen und öffentlichen Einrichtungen’ (or `Kommunalrichtlinie’ for short), the National Climate Initiative has started to promote large-scale, easily implementable LED projects. The goal is to ensure that as many municipalities as possible can lower energy costs with LED technology and benefit from the lessons learned during the UIP competition. Before 2011 the competition supported a variety of alternative technologies such as sodium-vapour lamps. Since then, however, the `Kommunalrichtlinie’ has funded only LED projects.

The Lead Market Initiative by the Federal Ministry for Education and Research (BMBF) and the Federal Ministry for the Environment (BMUB) is designed to increase public demand for LEDs and support research and development projects. One of its funded research projects is UNILED, a TU Berlin project that analyses barriers to LEDs investigates possible solutions. The final report is available on the TU Berlin website here. The Federal Ministry for Economic Affairs and Energy (BMWi) also funds research in this field. One example is the Performance Quality Label Project (PQL), which created a basis for the introduction of LED light standards. The final report can be found on the TU Darmstadt homepage.

As part of a TU Berlin project – LED-Laufsteg – researchers tested different LED light designs under real conditions on a walkway outside the German Museum of Technology in Berlin. The project showed the public the importance of light quality, road safety, energy efficiency, pole height, pole spacing, nearby structures, light distribution and light color. For more info about the project, see here.

Alongside public funding and low-interest loans, a strategy known as energy savings performance contracting can also help municipalities carry out expensive street lighting projects. It works like this: a local council contracts an energy service company to modernise the street lighting while assuming the initial investment costs. The municipality then uses the money it saves on energy to pay back the energy service company. This six-minute video [available only in German], created by The Berlin Energy Agency, provides an introduction to the subject.

The extent to which the energy service company gets involved depends largely on the details of the contract. Municipalities can decide who covers the costs (for maintenance, say) or where the management of the new lighting system should take place. There are also instances in which the energy service company is completely in charge of the energy supply for the lighting system. Though the Federal Ministry for the Environment (BMUB) recommends the use of energy savings performance contracting, not all areas benefit. Each municipality must decide for itself whether this approach is worthwhile.

Information for Municipalities

The following section contains links to websites with useful information for funding, appraising, planning, and introducing more energy-efficient street lighting.

Pilot Project Street Lighting 

The German Energy Agency (dena), in cooperation with ZVEI, the German Association of Towns and Municipalities (DStGB), and the Forum Contracting organization, has published a step-by-step planning guide for municipalities. The guidelines cover state analysis, planning, financing, acquisition, and maintenance. Each step comes with explanations of the accompanying standards, laws and directives. Additionally, municipalities can work out future saving potentials using the website’s cost calculator. www.lotse-strassenbeleuchtung.de

Energy Efficient Municipalities

The German Energy Agency (dena) provides helpful information about how municipalities can save energy. At www.energieeffiziente-kommune.de you can find a wide range of useful topics and contact information for consulting agencies and subsidy programs. 

Green Procurement

The Federal Environment Agency states that any type of public spending should be carried out with Germany’s environmental goals in mind while taking advantage of consumers’ growing environmental awareness to promote sustainable products. More information can be found at www.beschaffung-info.de. Resources on energy labelling for lamps and lights can be found on the websites of The Federal Institute for Materials Research and Testing (BAM), The Federal Environment Agency, and the EuP Network of the Ökopol Institute

The Environmental Innovation Program

The Environmental Innovation Program (UIP) funds large-scale pilot projects to test different advanced methods for reducing or preventing environmental damage. One of their funding priorities is energy-efficient street lighting, which includes municipal competition mentioned above.

Checklists and Guidelines from the German Electrical and Electronic Manufacturers' Association: ZVEI

In 2012, ZVEI published a checklist to assist municipalities when purchasing LED lights. The ZVEI Guidelines for LED Street Lighting from March 2016 is an ideal place to begin for those requiring a general introduction to the technical foundations of LED street lighting. Another, more detailed resource on LED lighting is the 2nd edition report titled Guideline to Reliable Planning to LED Lighting. The website licht.de, part of the ZVEI association, also provides a checklist with information on lighting design and installation to advise both public and private consumers. 

Service and Competence Centre: Municipal Climate Action

The Service and Competence Centre: Municipal Climate Action (SK:KK) supports public sector projects with a range of funding opportunities. The centre is run by the German Institute for Urbanism for the Federal Ministry for the Environment (BMUB). More information on its services, including their advice hotline, can be found at www.klimaschutz.de/kommunen.

Funding Database

The Federal Ministry for Economic Affairs and Energy has created a database of funding programs and grants at the state, federal and EU levels. The database also provides in-depth information on financing. 

Federal Funding for Municipalities

Germany’s Kommunalrichtlinie program `Richtlinie zur Förderung von Klimaschutzprojekten in sozialen, kulturellen und öffentlichen Einrichtungen’ supports the creation of comprehensive climate strategy plans at the municipal level. In doing so, it provides funding for a wide variety of municipal climate action projects, including the introduction of LED street and traffic lighting. Between 2008 and 2016, the program funded more than 10,000 projects in over 3,400 municipalities. Of these, some 2,800 projects in 1,700 municipalities were devoted to outdoor lighting. Municipalities can apply for this funding via the website of Jülich Project Management at www.ptj.de/klimaschutzinitiative-kommunen

Investment Loans for Municipalities from the KfW Development Bank

The KfW Development Bank offers investment loans for municipalities, which can be easily applied for via their website. More details about the loan are provided on this leaflet. For a simple overview of the KfW investment loan see licht.de, a project of ZVEI. 

Energy Savings Performance Contracting

The key to successful partnership between the municipality and the energy service company is a transparent contract design. As part of the LED Lead Market Initiative, the Sustainable Business Institute, together with the German Association of Towns and Municipalities and the ZVEI association, has drafted sample contracts for municipal outdoor lighting where the contracting partner (not the municipality) guarantees energy savings and assumes the risks when savings fall short. For sample contracts and more information, see www.licht.cfi21.org

More detailed information on energy savings performance contracting can be found on the website of the Contracting Competence Centre. Run by The German Energy Agency (dena), the centre provides contacts, providers, and examples of successful projects. 


Over the past ten years, LED technology has fundamentally transformed the lighting industry. For most street lighting applications, LED technology is quite advanced, though certain problems still remain. For instance, the individual components of many LED lights cannot be replaced, and even when they can, the labour costs can be more expensive than replacing the entire light. For the sake of sustainability and resource conservation, of course, it would be better to replace LED parts whenever possible and economically feasible. 

In the future, improvements in LED technology can serve to increase energy efficiency or to new areas of applications, such as panel-based lighting using OLEDs. Another improvement would be the introduction of smart control systems that increase energy efficiency and improve visibility. Simple controls systems for dimming street lights when pedestrians move out of range are already being deployed in some places. As the TU Berlin LED project showed, however, the potential of smart technology extends well beyond simple applications like these. Lighting that reacts differently to wet and dry weather and asymmetrical light beams can significantly increase visibility. Smart systems can be managed by a central control centre with access to additional information about traffic conditions and weather reports. This type of system is often referred to as a smart city. More information can be found in the CPG Newsletter on Smart Cities.

Various research projects are currently studying ways to improve LEDs and LED use. In UNILED 2 – the follow-up project to UNILED – the Karlsruhe Institute for Technology, TU Berlin, TU Darmstadt, and the TU Ilmenau are investigating different customisation options for needs-based street lighting. Researchers at the TU Berlin, as part of the StEffi Straßenbeleuchtung project, are examining ways to increase energy efficiency through strategic street light placement. Their preliminary findings indicate that better placement can reduce energy use by 50% in some cases.

Today, the modernisation of conventional lighting systems can produce energy savings of up to 80%. A careful assessment is required to find out when modernisation makes economic sense. Even if municipalities knew that the savings would pay off the initial investment within ten years, many would still have a hard time covering the initial costs. This is where funding programs, low-interest loans, and energy savings performance contracting all come into play. This newsletter contains links to Internet resources providing general information, consulting opportunities, sample contracts and funding applications.

The funding programs give every municipality the chance to benefit from the large energy savings of modern lighting technologies. This not only saves municipalities money. By using more energy-efficient lighting, municipalities can contribute to lowering German energy consumption and to aiding the country’s climate change mitigation efforts. 

Links and references 

Das Klima schützen, Kommunen fördern - Die Kommunalrichtlinie 2016 / 2017
Quelle: Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMUB)

Klimaschutz in neuem Licht - Die LED-Leitmarktinitiative: Innovation für Kommunen und Wirtschaft
Quelle: Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMUB)

Richtlinie zur Förderung von Klimaschutzprojekten in sozialen, kulturellen und öffentlichen Einrichtungen (Kommunalrichtlinie) im Rahmen der Nationalen Klimaschutzinitiative
Quelle: Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMUB)

LED-Laufsteg - Wissenschaftlicher Abschlussbericht
Quelle: Technische Universität Berlin

Quelle: Dipl.Ing. F. A. Bodenhaupt

Leuchtstoff und Lichtausbeute
Quelle: Christoph Heyen und Dieter Berndt auf treffpunkt-kommune.de des PVS - PRO VERLAG UND SERVICE GMBH & CO. KG

Photonik Forschung Deutschland - Förderinitiative „Intelligente Beleuchtung“
Quelle: Photonikforschung Deutschland / VDI Technologiezentrum GmbH

Quelle: Photonikforschung Deutschland / VDI Technologiezentrum GmbH

Die Lichtbranche - Fakten, Forderungen, Zahlen
Quelle: ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

Beleuchtung im Rahmen der Novellierung der Energieeinsparverordnung (Positionspapier)
Quelle: ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

licht.wissen 03 – Straßen, Wege und Plätze
Quelle: licht.de des ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

licht.wissen 17 – LED: Das Licht der Zukunft
Quelle: licht.de des ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

licht.wissen 20 – Nachhaltige Beleuchtung
Quelle: licht.de des ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.  

Information, funding and financial documents

Quelle: Umweltbundesamt

Quelle: Deutsche Energie-Agentur (dena)

Quelle: Deutsche Energie-Agentur (dena)

Quelle: Umweltbundesamt

Arbeits- und Entscheidungshilfe zur Auswahl von LED-Leuchten
Quelle: ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

Leitfaden für LED-Straßenbeleuchtung
Quelle: ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.  

Leitfadens Planungssicherheit in der LED-Beleuchtung, überarbeitete 2. Ausgabe
Quelle: ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

Checklisten – für Lichtplanung und Installation
Quelle: licht.de des ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

Quelle: Deutsches Institut für Urbanistik gGmbH für das Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit (BMUB)

IKK – Investitionskredit Kommunen
Quelle: KfW

Merkblatt IKK - Investitionskredit Kommunen (208)
Quelle: KfW

KfW-Förderprogramme für effiziente Beleuchtung
Quelle: licht.de des ZVEI – Zentralverband Elektrotechnik- und Elektronikindustrie e. V.

Quelle: Sustainable Business Institute (SBI) e.V.

Kompetenzzentrums Contracting
Quelle: Deutsche Energie-Agentur (dena)


Bundeswettbewerb Energieeffiziente Stadtbeleuchtung
Quelle: Umweltbundesamt

Energiesparen mit Garantie
Quelle: Berliner Energieagentur GmbH

LED-Leuchtmittel sparen Strom
Quelle: VDI Zentrum Ressourceneffizienz GmbH






German Environment Agency
Division III 2.4 (Waste Technology, Waste Technology Transfer)
Wörlitzer Platz 1
06844 Dessau-Roßlau


Editorial department: Ralf Menzel; Anne Bachmann; Christoph Mordziol

Author: Joscha Steinbrenner

This Newsletter contains external links. CPG has no influence on the content of these linked websites. At the time of production of these newsletters no illigal content was detected. In case of any illigal, inaccurate or incomplete content, as well as damages deriving from using external information only the provider of those websites that are linked is to be hold liable. 

Figure 1: Umweltbundesamt
Figure 2: ZVEI
Figure 3: licht.de
Figure 4: licht.wissen 03
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