Street light#Beacon lights

{{main article|Oil lamp|Gas lighting}}

Early lamps were used in the Ancient Greek and Ancient Roman civilizations, where light primarily served the purpose of security, to both protect the wanderer from tripping on the path over something and keep potential robbers at bay. At that time, oil lamps were used predominantly, as they provided a long-lasting and moderate flame. A slave responsible for lighting the oil lamps in front of Roman villas was called a {{lang|la|lanternarius}}.{{Cite journal |last=de Beer |first=E. S. |date=1941 |title=The Early History of London Street-Lighting |url=https://www.jstor.org/stable/24401837 |journal=History |volume=25 |issue=100 |pages=311–324 |issn=0018-2648}}

In the words of Edwin Heathcote, "Romans illuminated the streets with oil lamps, and cities from Baghdad to Cordoba were similarly lit when most of Europe was living in what it is now rather unfashionable to call the Dark Ages but which were, from the point of view of street lighting, exactly that."{{cite web |author1=Edwin Heathcote |author1-link=Edwin Heathcote |title=From pillar to lamp post: lighting city streets |url=https://www.architectural-review.com/essays/from-pillar-to-lamp-post-lighting-city-streets |publisher=Architectural Review |access-date=15 May 2023 |date=7 September 2021}}{{cite web |author1=Edwin Heathcote |title=Architecture: how street lights have illuminated city life |url=https://www.ft.com/content/5f4dfbc2-c32c-11e4-9c27-00144feab7de |work=Financial Times|location=London |access-date=15 May 2023 |date=13 March 2015}}

So-called "link boys" escorted people from one place to another through the murky, winding streets of medieval towns.

Before incandescent lamps, candle lighting was employed in cities. The earliest lamps required that a lamplighter tour the town at dusk, lighting each of the lamps. According to some sources, illumination was ordered in London in 1417 by Sir Henry Barton, Mayor of London though there is no firm evidence of this.Roskell, J. S. and Clark, L. and Rawcliffe, C. (editors) [http://www.historyofparliamentonline.org/volume/1386-1421/member/barton-henry-1435 BARTON, Henry (d.1435), of London. – History of Parliament Online] {{webarchive|url=https://web.archive.org/web/20140816045930/http://www.historyofparliamentonline.org/volume/1386-1421/member/barton-henry-1435 |date=16 August 2014 }}, The History of Parliament: the House of Commons 1386–1421. {{ISBN|9780862999438}}. 1993.

Public street lighting was first developed in the 16th century,{{cite journal | title = The Policing of Street Lighting | first = Wolfgang | last = Schivelbusch | journal = Yale French Studies| number = 73 | year = 1987 | pages = 61–74 | doi = 10.2307/2930197 | jstor = 2930197 }} and accelerated following the invention of lanterns with glass windows by Edmund Heming in London and Jan van der Heyden in Amsterdam,Ekirch, A. Roger, 1950At day’s close : night in times past / A. Roger Ekirch.—Ist ed. p.72 ISBN 0-393-05089-0, W. W. Norton & Company, Inc., 500 Fifth Avenue, New York, N.Y. 10110 Www.wwnorton.com which greatly improved the quantity of light. In 1588 the Parisian Parliament decreed that a torch be installed and lit at each intersection, and in 1594 the police changed this to lanterns.{{Sfn|Fierro|1996|pages=835–836}} Still, in the mid 17th century it was a common practice for travelers to hire a lantern-bearer if they had to move at night through the dark, winding streets.{{cite journal | title = Art V. Social Life of England and France, A Comparative View of the Social Life of England and France, from the Restoration of Charles II. to the French Revolution. By the Editor of Madame du Deffand's Letters | journal = Southern Journal | number = XII | date = November 1830 | location = Charleston | publisher = A. E. Miller | page = 395 | url = https://books.google.com/books?id=gbIRAAAAYAAJ&pg=PA395 | quote = Until 1662, the streets of Paris were so dark and dangerous, that the monopoly of flambeau-bearers and lantern-carriers was established for the security of night visiting in Paris.}} King Louis XIV authorized sweeping reforms in Paris in 1667, which included the installation and maintenance of lights on streets and at intersections, as well as stiff penalties for vandalizing or stealing the fixtures.{{citation | url = https://www.laphamsquarterly.org/roundtable/how-paris-became-city-light | title = How Paris Became the City of Light: Louis XIV hires the city's first police chief | first = Holly | last = Tucker | date = 22 March 2017 | work = Lapham's Quarterly | access-date = 17 February 2020}} Paris had more than 2,700 streetlights by the end of the 17th century, and twice as many by 1730.{{cite book | title = What We Did in Bed: A Horizontal History | first1 = Brian | last1 = Fagan | first2 = Nadia | last2 = Durrani | year = 2019 | publisher = Yale University Press | location = New Haven and London | isbn = 978-0-300-22388-0 | page = 41}} Under this system, streets were lit with lanterns suspended {{convert|20|yd|m}} apart on a cord over the middle of the street at a height of {{convert|20|ft|m}}; as an English visitor enthused in 1698, 'The streets are lit all winter and even during the full moon!'{{sfn|Fierro|1996|page=837}} In London, public street lighting was implemented around the end of the 17th century; a diarist wrote in 1712 that 'All the way, quite through Hyde Park to the Queen's Palace at Kensington, lanterns were placed for illuminating the roads on dark nights.'{{cite journal | url = https://books.google.com/books?id=oz08AQAAMAAJ&pg=185 | title = Historical Sketch of Street Lighting | first = Preston S. | last = Millar | pages = 185–202 | journal = Transactions of the Illuminating Engineering Society | publisher = Illuminating Engineering Society | location = New York City | volume = XV | number = 3 | date = 30 April 1920}}

A much-improved oil lantern, called a {{lang|fr|réverbère}}, was introduced in 1745 and improved in subsequent years. The light shed from these réverbères was considerably brighter, enough that some people complained of glare. These lamps were attached to the top of lampposts; by 1817, there were 4,694 lamps on the Paris streets.{{citation needed|date=February 2020}} During the French Revolution (1789–1799), the revolutionaries found that the lampposts were a convenient place to hang aristocrats and other opponents.{{Sfn|Fierro|1996|page=836}}

{{main article|Gas lighting}}

The first widespread system of street lighting used piped coal gas as fuel. Stephen Hales was the first person who procured a flammable fluid from the actual distillation of coal in 1726 and John Clayton, in 1735, called gas the "spirit" of coal and discovered its flammability by accident.

File:Murdoch House & St. Rumon's Gardens.jpg, UK, the first domestic house in the world to be lit by gas]]

William Murdoch (sometimes spelled "Murdock") was the first to use this gas for the practical application of lighting. In the early 1790s, while overseeing the use of his company's steam engines in tin mining in Cornwall, Murdoch began experimenting with various types of gas, finally settling on coal-gas as the most effective. He first lit his own house in Redruth, Cornwall in 1792.Janet Thomson; The Scot Who Lit The World, The Story of William Murdoch Inventor of Gas Lighting; 2003; {{ISBN|0-9530013-2-6}} In 1798, he used gas to light the main building of the Soho Foundry and in 1802 lit the outside in a public display of gas lighting, the lights astonishing the local population.

File:Street Lighting and Posts Morris Tasker and Co Illustrated Catalogue (1871).jpg

The first public street lighting with gas was demonstrated in Pall Mall, London on 4 June 1807 by Frederick Albert Winsor.'Pall Mall, South Side, Past Buildings: Nos 93–95 Pall Mall, F.A. Winsor and the development of gas lighting', in Survey of London: Volumes 29 and 30, St James Westminster, Part 1, ed. F H W Sheppard (London, 1960), pp. 352–354. British History Online http://www.british-history.ac.uk/survey-london/vols29-30/pt1/pp352-354 [accessed 10 August 2023].

In 1811, Engineer Samuel Clegg designed and built what is now considered the oldest extant gasworks in the world. Gas was used to light the worsted mill in the village of Dolphinholme in North Lancashire. The remains of the works, including a chimney and gas plant, have been put on the National Heritage List for England. Clegg's installation saved the building's owners the cost of up to 1,500 candles every night. It also lit the mill owner's house and the street of millworkers' houses in Dolphinholme.{{cite web | url=https://historicengland.org.uk/whats-new/news/earliest-surviving-gasworks-remains-protected/ | title=Remains of World's Earliest Surviving Gasworks Now Protected | Historic England | date=15 July 2020 }}

In 1812, Parliament granted a charter to the London and Westminster Gas Light and Coke Company, and the first gas company in the world came into being. Less than two years later, on 31 December 1813, the Westminster Bridge was lit by gas.{{cite web | author=The London Gasketeers | title=The London Gasketeers | website=The London Gasketeers | date=15 March 2019 | url=https://thelondongasketeers.com/a-brief-history | access-date=12 July 2024}}

Following this success, gas lighting spread outside London, both within Britain and abroad. The first place outside London in England to have gas lighting, was Preston, Lancashire in 1816, where Joseph Dunn's Preston Gaslight Company introduced a new, brighter gas lighting. Another early adopter was the city of Baltimore, where the gaslights were first demonstrated at Rembrandt Peale's Museum in 1816, and Peale's Gas Light Company of Baltimore provided the first gas streetlights in the United States. In the 1860s, streetlights were started in the Southern Hemisphere in New Zealand.

Kerosene streetlamps were invented by Polish pharmacist Ignacy Łukasiewicz in the city of Lemberg (Austrian Empire), in 1853. His kerosene lamps were later widely used in Bucharest, Paris, and other European cities. He went on to open the world's first mine in 1854 and the world's first kerosene refinery in 1856 in Jasło, Poland.{{cite web |last1=Kępa |first1=Marek |title=Ignacy Łukasiewicz: The Generous Inventor of the Kerosene Lamp |url=https://culture.pl/en/article/ignacy-lukasiewicz-the-generous-inventor-of-the-kerosene-lamp |website=Culture.pl |access-date=26 August 2024}}

In Paris, public street lighting was first installed on a covered shopping street, the Passage des Panoramas, in 1817, private interior gas lighting having been previously demonstrated in a house on the rue Saint-Dominique seventeen years prior. The first gas lamps on the main streets of Paris appeared in January 1829 on the place du Carrousel and the Rue de Rivoli, then on the rue de la Paix, place Vendôme, and rue de Castiglione. By 1857, the Grands Boulevards were all lit with gas; a Parisian writer enthused in August 1857: "That which most enchants the Parisians is the new lighting by gas of the boulevards...From the church of the Madeleine all the way to rue Montmartre, these two rows of lamps, shining with a clarity white and pure, have a marvelous effect." The gaslights installed on the boulevards and city monuments in the 19th century gave the city the nickname "The City of Light."{{Sfn|Fierro|1996|page=838}}

Oil-gas appeared in the field as a rival of coal-gas. In 1815, John Taylor patented an apparatus for the decomposition of "oil" and other animal substances. Public attention was attracted to "oil-gas" by the display of the patent apparatus at Apothecary's Hall, by Taylor & Martineau.

During the period of gas lighting, lights were not generally left on for the entire night, nor were they necessarily turned on during periods of moonlight. In an article about the development of streetlighting in three industrial cities, Mark Bouman reported that Max Greve, the mayor of Bochum, Germany, "fought all his life against 'absurd modernism,' which would have had the lights on even when the moon shone."{{cite journal |last1=Bouman |first1=Mark J. |title=Luxury and Control: The Urbanity of Street Lighting in Nineteenth-Century Cities |journal=Journal of Urban History |date=1 November 1987 |volume=14 |issue=1 |page=21 |doi=10.1177/009614428701400102 |url=https://doi.org/10.1177/009614428701400102 |access-date=14 May 2025 |language=EN |issn=0096-1442|url-access=subscription }}

Farola fernandina is a traditional design of gas streetlight which remains popular in Spain. Essentially, it is a neoclassical French style of gas lamp dating from the late 18th century. It may be either a wall-bracket or standard lamp. The standard base is cast metal with an escutcheon bearing two intertwined letters 'F', the Royal cypher of King Ferdinand VII of Spain{{cite web |url = http://esasevilla.blogspot.com.es/2010/05/las-fernandinas.html |publisher = Esa Sevilla blogspot |title = Las fernandinas |date = 22 May 2010 |language = es |access-date = 19 June 2014 |url-status = live |archive-url = https://web.archive.org/web/20140606233239/http://esasevilla.blogspot.com.es/2010/05/las-fernandinas.html |archive-date = 6 June 2014}} and commemorates the date of the birth of his daughter, the Infanta Luisa Fernanda, Duchess of Montpensier.{{cite web |url = http://farolasfernandinas.blogspot.com.es/ |publisher = Amigos de las farolas ferdinandinas |title = "Ya a la venta el libro "Las farolas fernandinas por los cuatro costados" book review |date = 7 September 2009 |access-date = 9 June 2014 |url-status = live |archive-url = https://web.archive.org/web/20140517133224/http://farolasfernandinas.blogspot.com.es/ |archive-date = 17 May 2014}}

File:Base de farola fernandina.jpg|Typical base and escutcheon of a farola fernandina

File:Aranjuez FarolaFernandina.jpg|A farola fernandina in Aranjuez

File:Aranjuez PalacioReal Farola.jpg|Streetlight in Ferdinand VII style near the Royal Palace of Aranjuez

File:Paris Notre Dame19042017.jpg|

File:Yablochkov candles illuminating Avenue de l'Opera ca1878.jpg arc lamp on the Avenue de l'Opera in Paris (1878), the first form of electric street lighting]]

File:BCBG Lamppost 01.JPG, Brisbane]]

The first electric street lighting employed arc lamps, initially the "electric candle", "Jablotchkoff candle", or "Yablochkov candle", developed by Russian Pavel Yablochkov in 1875. This was a carbon arc lamp employing alternating current, which ensured that both electrodes were consumed at equal rates. In 1876, the common council of the city of Los Angeles ordered four arc lights installed in various places in the fledgling town for street lighting.William H. Workman, The City That Grew (1929) Mirror-Press, Los Angeles, p.

On 30 May 1878, the first electric streetlights in Paris were installed on the avenue de l'Opera and the Place de l'Étoile, around the Arc de Triomphe, to celebrate the opening of the Paris Universal Exposition. In 1881, to coincide with the Paris International Exposition of Electricity, streetlights were installed on the major boulevards.{{Sfn|Fierro|1996|page=628}}

The first streets in London lit with the electrical arc lamp were by the Holborn Viaduct and the Thames Embankment in 1878. More than 4,000 were in use by 1881, though by then an improved differential arc lamp had been developed by Friedrich von Hefner-Alteneck of Siemens & Halske. The United States was quick in adopting arc lighting, and by 1890 over 130,000 were in operation in the US, commonly installed in exceptionally tall moonlight towers.

Arc lights had two major disadvantages. First, they emit an intense and harsh light which, although useful at industrial sites like dockyards, was discomforting in ordinary city streets. Second, they are maintenance-intensive, as carbon electrodes burn away swiftly. With the development of cheap, reliable and bright incandescent light bulbs at the end of the 19th century, arc lights passed out of use for street lighting, but remained in industrial use longer.

File:Map of electric street lighting in Tamworth NSW, 1888.jpg, showing the position of leads and lights along the network of city streets in 1888]]

The first street to be lit by an incandescent lightbulb was Mosley Street, in Newcastle. The street was lit for one night by Joseph Swan's incandescent lamp on 3 February 1879.{{cite web |url=http://home.frognet.net/~ejcov/jwswan.html |title=Sir Joseph Wilson Swan |publisher=home.frognet.net |access-date=16 October 2010 |url-status=dead |archive-url=https://web.archive.org/web/20110510005841/http://home.frognet.net/~ejcov/jwswan.html |archive-date=10 May 2011}}{{cite web |url=http://www.rsc.org/Chemsoc/Activities/ChemicalLandmarks/UK/JosephSwan.asp |title=Sir Joseph Swan, The Literary & Philosophical Society of Newcastle |date=3 February 2009 |publisher=rsc.org |access-date=16 October 2010 |archive-url=https://web.archive.org/web/20110901143453/http://www.rsc.org/Chemsoc/Activities/ChemicalLandmarks/UK/JosephSwan.asp |archive-date = 1 September 2011 |url-status = dead}} Consequently, Newcastle has the first city street in the world to be lit by electric lighting.{{cite web| title = Electric lighting| publisher = ncl.ac.uk| url = http://www.ncl.ac.uk/library/special-collections/exhibitions/current-and-past-exhibitions/very_truly_yours/science/swan/electric_light/| access-date = 3 June 2014| url-status = dead| archive-url = https://web.archive.org/web/20140606212620/http://www.ncl.ac.uk/library/special-collections/exhibitions/current-and-past-exhibitions/very_truly_yours/science/swan/electric_light/| archive-date = 6 June 2014}}

The first city in the United States to successfully demonstrate electric lighting was Cleveland, Ohio, with 12 electric lights around the Public Square road system on 29 April 1879.{{cite web |url=https://case.edu/ech/articles/p/public-square |title=Encyclopedia of Cleveland History|date=18 June 2018}}{{cite web |url=https://clevelandmagazine.com/cleader/government/articles/cleveland-was-the-first-city-of-light |title=Cleveland was the First City of Light}} Wabash, Indiana, lit 4 Brush arc lamps with 3,000 candlepower each, suspended over their courthouse on 2 February 1880, making the town square "as light as midday".{{cite web |url=http://www.electricmuseum.com/exhibits/arclamps/brush.shtml |title=Brush Arc Lighting |archive-url=https://web.archive.org/web/20080724073937/http://www.electricmuseum.com/exhibits/arclamps/brush.shtml |archive-date = 24 July 2008 |url-status = dead}}

Kimberley, Cape Colony (modern South Africa), was the first city in the Southern Hemisphere and in Africa to have electric streetlights – with 16 first lit on 2 September 1882.{{cite web |url=https://www.kimberley.org.za/2-september-today-in-kimberleys-history/ |title=Today in Kimberley's History History 2 September|date=2 September 2015}}{{cite web |url=http://www.solplaatje.org.za/explore_history.php |title=Timeline of Firsts |access-date=11 January 2010 |url-status=live |archive-url=https://web.archive.org/web/20100928112704/http://www.solplaatje.org.za/explore_history.php |archive-date=28 September 2010}} The system was only the second in the world, after that of Philadelphia, to be powered municipally.

In Central America, San Jose, Costa Rica, lit 25 lamps powered by a hydroelectric plant on 9 August 1884.{{cite web | title=Is Costa Rica Different? A Treasure Chest of Discoveries | website=ReVista | date=20 April 2024 | url=https://revista.drclas.harvard.edu/is-costa-rica-different-a-treasure-chest-of-discoveries/ | access-date=12 July 2024}}

Nuremberg was the first city in Germany to have electric public lighting on 7 June 1882, followed by Berlin on 20 September 1882 (Potsdamer Platz only).

Temesvár (Timișoara in present-day Romania) was the first city in the Austrian-Hungarian Monarchy to have electric public lighting, on 12 November 1884; 731 lamps were used.{{cite web | title=History-1884 | website=Transelectrica | date=14 April 2016 | url=https://www.transelectrica.ro/en/web/tel/istoric-1884 | access-date=12 July 2024}}

On 9 December 1882, Brisbane, Queensland, Australia was introduced to electricity by having a demonstration of 8 arc lights, erected along Queen Street Mall. The power to supply these arc lights was taken from a 10 hp Crompton DC generator driven by a Robey steam engine in a small foundry in Adelaide Street and occupied by J. W. Sutton and Co.{{cite web | title=Early Electric Lighting | website=Queen's Wharf History | url=http://queenswharf.org/stories/early-electric-lighting/ | access-date=12 July 2024}} In 1884, Walhalla, Victoria, had two lamps installed on the main street by the Long Tunnel (Gold) Mining Company. In 1886, the isolated mining town of Waratah in Tasmania was the first to have an extensive system of electrically powered street lighting installed.{{cite journal |last=Preston |first=Keith |date=September 2010 |title=Mount Bischoff Tin Mines: Pioneers of water power in the Tasmanian mining industry |journal=Journal of Australasian Mining History |volume=8 | url=https://www.mininghistory.asn.au/wp-content/uploads/9-Preston.Vol_.8..compressed.pdf |pages=148–171 }} In 1888, the New South Wales town of Tamworth installed a large system illuminating a significant portion of the city, with over 13 km of streets lit{{cite news |last=Correspondent |date=12 November 1888 |title=STREET LIGHTING BY ELECTRICITY |url=https://trove.nla.gov.au/newspaper/article/6908584 |work=Melbourne Argus |access-date=9 November 2018}} by 52 incandescent lights and 3 arc lights.{{cite book |last=Lobsey |first=Ian |year=1988 |title=City of light |publisher=Peel-Cunningham County Council |pages=35–63 |isbn=978-0731657780}} Powered by a municipal power company, this system gave Tamworth the title of "First City of Light" in Australia.

On 10 December 1885, Härnösand became the first town in Sweden with electric street lighting, following the Gådeå power station being taken into use.{{cite news|url=https://www.hemab.se/elnat/omvartelnat/elenshistoriaiharnosand.4.4217f32e1628bc6795e35a8.html|title=Elens historia i Härnösand|publisher=Härnösand energi och miljö|language=Swedish|date=June 2016|accessdate=20 February 2021}}

Incandescent lamps were primarily used for street lighting until the advent of high-intensity gas-discharge lamps. They were often operated at high-voltage series circuits. Series circuits were popular since their higher voltage produced more light per watt consumed. Furthermore, before the invention of photoelectric controls, a single switch or clock could control all the lights in an entire district.

To avoid having the entire system go dark if a single lamp burned out, each streetlamp was equipped with a device that ensured that the circuit would remain intact. Early series streetlights were equipped with isolation transformers.{{cite book |url=https://books.google.com/books?id=BhYBAAAAMAAJ&q=%22general+electric+review%22 |title=General Electric review |volume=23 |url-status=live |archive-url=https://web.archive.org/web/20110511123841/http://books.google.com/books?id=BhYBAAAAMAAJ&printsec=frontcover&dq=%22general+electric+review%22 |archive-date=11 May 2011 |year=1920 |publisher=General Electric Company }} that would allow current to pass across the transformer whether the bulb worked or not.

Later, the film cutout was invented. This was a small disk of insulating film that separated two contacts connected to the two wires leading to the lamp. If the lamp failed (an open circuit), the current through the string became zero, causing the voltage of the circuit (thousands of volts) to be imposed across the insulating film, penetrating it (see Ohm's law). In this way, the failed lamp was bypassed and power was restored to the rest of the district. The streetlight circuit contained an automatic current regulator, preventing the current from increasing as lamps burned out, preserving the life of the remaining lamps. When the failed lamp was replaced, a new piece of film was installed, once again separating the contacts in the cutout. This system was recognizable by the large porcelain insulator separating the lamp and reflector from the mounting arm. This was necessary because the two contacts in the lamp's base may have operated at several thousand volts above ground.

File:Bus at Night.jpg in the UK]]

File:Na-light.jpg running at full brightness]]

File:Sodiumlamp.jpg

File:Prismalence street light.jpg street lighting]]{{See also|LED street light|Solar street light}}

Today, street lighting commonly uses high-intensity discharge lamps. Low-pressure sodium (LPS) lamps became commonplace after World War II for their low power consumption and long life. Late in the 20th century, high-pressure sodium (HPS) lamps were preferred, taking further the same virtues.{{cite web |author=Bullough, John |author2=MS Rea |author3=Y. Akashi |name-list-style=amp |title=Several views of metal halide and high pressure sodium lighting for outdoor applications |date=2009 |publisher=Lighting Research and Technology |page=31: 297–320 |url=http://www.lrc.rpi.edu/programs/transportation/projects/OutdoorLightingTypes.asp |url-status=live |archive-url=https://web.archive.org/web/20100609221917/http://www.lrc.rpi.edu/programs/transportation/projects/OutdoorLightingTypes.asp |archive-date=9 June 2010}} Such lamps provide the greatest amount of photopic illumination for the least consumption of electricity.

Two national standards now allow for variation in illuminance when using lamps of different spectra. In Australia, HPS lamp performance needs to be reduced by a minimum value of 75%. In the UK, illuminances are reduced with higher values S/P ratio.Fotios S and Goodman T. Proposed UK Guidance for Lighting in Residential Roads. Lighting Research & Technology, 2012; 44(1); 69–83Institution of Lighting Professionals (ILP). Professional Lighting Guide PLG03:2012. Lighting for Subsidiary Roads: Using white light sources to balance energy efficiency and visual amenity. Rugby; ILP

New street lighting technologies, such as LED or induction lights, emit a white light that provides high levels of scotopic lumens. It is a commonly accepted practice to justify and implement a lower luminance level for roadway lighting based on increased scotopic lumens provided by white light. However, this practice fails to provide the context needed to apply laboratory-based visual performance testing to the real world. Critical factors such as visual adaptation are left out of this practice of lowering luminance levels, leading to reduced visual performance. Additionally, there have been no formal specifications written around Photopic/Scotopic adjustments for different types of light sources, causing many municipalities and street departments to hold back on implementation of these new technologies until the standards are updated. Eastbourne in East Sussex, UK is currently undergoing a project to see 6000 of its streetlights converted to LED and will be closely followed by Hastings in early 2014.ESCC Highways/Colas Electrical Many UK councils are undergoing mass-replacement schemes to LED, and though streetlights are being removed along many long stretches of UK motorways (as they are not needed and cause light pollution), LEDs are preferred in areas where lighting installations are necessary.

Milan, Italy, is the first major city to have entirely switched to LED lighting.{{cite web |url=http://ec.europa.eu/information_society/newsroom/cf/dae/document.cfm?doc_id=7828 |title=Sorry |access-date=20 November 2015 |url-status=live |archive-url=https://web.archive.org/web/20151121085839/http://ec.europa.eu/information_society/newsroom/cf/dae/document.cfm?doc_id=7828 |archive-date=21 November 2015}}

In North America, the city of Mississauga, Canada was one of the first and largest LED conversion projects, with over 46,000 lights converted to LED technology between 2012 and 2014. It is also one of the first cities in North America to use Smart City technology to control the lights. DimOnOff, a company based in Quebec City, was chosen as a Smart City partner for this project.{{cite web |url=https://static1.squarespace.com/static/546bbd2ae4b077803c592197/t/5519578ae4b0ef9291b864a0/1427724170603/Mississauga+Case+Study+Final.pdf |title=Archived copy |access-date=16 July 2016 |url-status=live |archive-url=https://web.archive.org/web/20161009165549/https://static1.squarespace.com/static/546bbd2ae4b077803c592197/t/5519578ae4b0ef9291b864a0/1427724170603/Mississauga+Case+Study+Final.pdf |archive-date=9 October 2016}}{{cite web |url=http://www.lapresse.ca/le-soleil/affaires/actualite-economique/201506/19/01-4879627-eclairage-a-la-del-dimonoff-realise-le-plus-gros-projet-de-conversion-en-amerique.php |title=Éclairage à la DEL: DimOnOff réalise le plus gros projet de conversion en Amérique | Yves Therrien | Actualité économique |access-date=16 July 2016 |url-status=live |archive-url=https://web.archive.org/web/20161011190356/http://www.lapresse.ca/le-soleil/affaires/actualite-economique/201506/19/01-4879627-eclairage-a-la-del-dimonoff-realise-le-plus-gros-projet-de-conversion-en-amerique.php |archive-date=11 October 2016}} In the United States, the city of Ann Arbor, Michigan was the first metropolitan area to fully implement LED street lighting in 2006. Since then, sodium-vapor lamps were slowly being replaced by LED lamps.Staff, S. L. (20 November 2015). History of street lighting in the USA. LED Lighting Distributor and Implementation Company. https://www.stouchlighting.com/blog/history-of-street-lighting-in-the-usa#:~:text=LED%3A,Alaska%20installed%204%2C000%20LED%20streetlights.

Photovoltaic-powered LED luminaires are gaining wider acceptance. Preliminary field tests show that some LED luminaires are energy-efficient and perform well in testing environments.{{cite web |url=http://www.lrc.rpi.edu/programs/DELTA/pdf/DELTA-Post-topPhotovoltaic.pdf |title=Field Test |publisher=lrc.rpi.edu |access-date=16 October 2010 |url-status=live |archive-url=https://web.archive.org/web/20101204215609/http://www.lrc.rpi.edu/programs/DELTA/pdf/DELTA-Post-topPhotovoltaic.pdf |archive-date=4 December 2010}}

In 2007, the Civil Twilight Collective created a variant of the conventional LED streetlight, namely the Lunar-resonant streetlight.{{cite web |url=http://www.archnewsnow.com/features/Feature226.htm |title=Lunar resonant streetlights as winner of Metropolis Next Generation Design Prize |url-status=live |archive-url=https://web.archive.org/web/20100827162136/http://www.archnewsnow.com/features/Feature226.htm |archive-date=27 August 2010}}{{cite web |url=http://www.civiltwilightcollective.com/lunar1.htm |title=Civil Twilight Collective homepage |url-status=live |archive-url=https://web.archive.org/web/20110514145932/http://www.civiltwilightcollective.com/lunar1.htm |archive-date=14 May 2011 |date=6 September 2016 }} These lights increase or decrease the intensity of the streetlight according to the lunar light. This streetlight design thus reduces energy consumption as well as light pollution.

File:Street lamp hunting lodge Moenchbruch - Straßenlaterne Jagdschloss Mönchbruch.jpg, Germany]]

File:Street lamp during a snowfall.JPG

Two very similar measurement systems were created to bridge the scotopic and photopic luminous efficiency functions,Rea M, Bullough J, Freyssinier-Nova J, Bierman A. A proposed unified system of photometry. Lighting Research & Technology 2004; 36(2):85.Goodman T, Forbes A, Walkey H, Eloholma M, Halonen L, Alferdinck J, Freiding A, Bodrogi P, Varady G, Szalmas A. Mesopic visual efficiency IV: a model with relevance to nighttime driving and other applications. Lighting Research & Technology 2007; 39(4):365.{{cite web |url=http://www.lrc.rpi.edu/researchAreas/pdf/GrotonFinalReport.pdf |title=Mesopic street lighting demonstration and evaluation final report |author=Peter Morante |publisher=lrc.rpi.edu |date=31 January 2008 |access-date=16 October 2010 |url-status=live |archive-url=https://web.archive.org/web/20101204183610/http://www.lrc.rpi.edu/researchAreas/pdf/GrotonFinalReport.pdf |archive-date=4 December 2010}} creating a Unified System of Photometry.{{cite web |url=http://www.lrc.rpi.edu/resources/newsroom/pdf/2006/DriverResponseProject.pdf |title=Driver response to peripheral moving targets under mesopic light levels |publisher=lrc.rpi.edu |access-date=16 October 2010 |url-status=live |archive-url=https://web.archive.org/web/20101204183809/http://www.lrc.rpi.edu/resources/newsroom/pdf/2006/DriverResponseProject.pdf |archive-date=4 December 2010}}Akashi, Y., M. S. Rea and J. D. Bullough. 2007. Driver decision making in response to peripheral moving targets under mesopic light levels. Lighting Research and Technology 39(1): 53–67. These mesopic visual performance models are conducted in laboratory conditions in which the viewer is not exposed to higher levels of luminance than the level being tested for. Further research is needed to bring additional factors into these models such as visual adaptation and the biological mechanics of rod cells before these models are able to accurately predict visual performance in real world conditions. The current understanding of visual adaptation and rod cell mechanics suggests that any benefits from rod-mediated scotopic vision are difficult, if not impossible, to achieve in real world conditions under the presence of high luminance light sources.{{Cite journal |last1=Uchida |first1=T |last2=Ayama |first2=M |last3=Akashi |first3=Y |last4=Hara |first4=N |last5=Kitano |first5=T |last6=Kodaira |first6=Y |last7=Sakai |first7=K |date=February 2016 |title=Adaptation luminance simulation for CIE mesopic photometry system implementation |url=http://journals.sagepub.com/doi/10.1177/1477153515626210 |journal=Lighting Research & Technology |language=en |volume=48 |issue=1 |pages=14–25 |doi=10.1177/1477153515626210 |s2cid=112710450 |issn=1477-1535|url-access=subscription }}{{Cite book |last=van Bommel |first=Wout |url=https://link.springer.com/10.1007/978-3-319-11466-8 |title=Road Lighting: Fundamentals, Technology and Application |date=2015 |publisher=Springer International Publishing |isbn=978-3-319-11465-1 |location=Cham |language=en |doi=10.1007/978-3-319-11466-8}}{{Cite journal |last1=Aguilar |first1=M. |last2=Stiles |first2=W.S. |date=January 1954 |title=Saturation of the Rod Mechanism of the Retina at High Levels of Stimulation |url=https://www.tandfonline.com/doi/full/10.1080/713818657 |journal=Optica Acta: International Journal of Optics |language=en |volume=1 |issue=1 |pages=59–65 |doi=10.1080/713818657 |bibcode=1954AcOpt...1...59A |issn=0030-3909|url-access=subscription }}

Outdoor Site-Lighting Performance (OSP) is a method for predicting and measuring three different aspects of light pollution: glow, trespass and glare.{{cite journal |author=Brons, J. A. |author2=J. D. Bullough |author3=M. S. Rea |name-list-style=amp |date=2008 |title=Outdoor site-lighting performance: A comprehensive and quantitative framework for assessing light pollution |journal=Lighting Research & Technology |volume=40 |issue=3 |page=40(3): 201–224 |doi=10.1177/1477153508094048 |s2cid=109408921 }} Using this method, lighting specifiers can quantify the performance of existing and planned lighting designs and applications to minimize excessive or obtrusive light leaving the boundaries of a property.

File:Lampu Jalan Jakarta.jpg]]

Major advantages of street lighting include prevention of automobile accidents and increase in safety.Rea, M. S., J. D. Bullough, C. R. Fay, J. A. Brons, J. Van Derlofske and E. T. Donnell. 2009. Review of the Safety Benefits and Other Effects of Roadway Lighting [report to the National Cooperative Highway Research Program]. Washington, DC: Transportation Research Board. Studies have shown that darkness results in numerous crashes and fatalities, especially those involving pedestrians; pedestrian fatalities are 3 to 6.75 times more likely in the dark than in daylight.Sullivan, J.M., and Flannigan, M.J. (1999) Assessing the Potential Benefit of Adaptive Headlighting Using Crash Databases, Report No. UMTRI-99-21. University of Michigan Transportation Research Institute. At least in the 1980s and 1990s, when automobile crashes were far more common,{{cite journal|last1=Buehler|first1=Ralph|last2=Pucher|first2=John|title=Trends in Walking and Cycling Safety: Recent Evidence From High-Income Countries, With a Focus on the United States and Germany|journal=American Journal of Public Health|date=February 2017|volume=107|issue=2|pages=281–287|doi=10.2105/AJPH.2016.303546|pmid=27997241|pmc=5227927}} street lighting was found to reduce pedestrian crashes by approximately 50%.Schwab, R.N., Walton, N.E., Mounce, J.M., and Rosenbaum, M.J. (1982) Synthesis of Safety Research Related to Traffic Control and Roadway Elements-Volume 2, Chapter 12: Highway Lighting. Report No. FHWA-TS-82-233. Federal Highway Administration.Elvik, R. (1995) "Meta-Analysis of Evaluations of Public Lighting as Accident Countermeasure." Transportation Research Record 1485, TRB, National Research Council, Washington, D.C., pp. 112–123.Commission Internationale de l'Éclairage. (1992) Road Lighting as an Accident Countermeasure. CIE No. 93. Vienna, Austria: Commission Internationale de l'Éclairage. Furthermore, in the 1970s, lighted intersections and highway interchanges tended to have fewer crashes than unlighted intersections and interchanges.Box, P.C. (1970) Relationship Between Illumination and Freeway Accidents. IERI Project 85-67 Illuminating Research Institute, New York April, pp. 1–83.

Some say lighting reduces crime,{{cite journal |last1=Chalfin |first1=Aaron |title=Reducing Crime Through Environmental Design: Evidence from a Randomized Experiment of Street Lighting in New York City |journal=National Bureau of Economic Research |series=Working Paper Series |date=May 2019 |doi=10.3386/w25798 |s2cid=155976490 |url=https://www.nber.org/papers/w25798#fromrss |access-date=7 May 2019}}{{cite web|url=https://www.ledsmagazine.com/architectural-lighting/article/16701511/major-study-finds-outdoor-lighting-cut-crime-by-39|title=Major study finds outdoor lighting cut crime by 39% (UPDATED)|date=13 March 2018 }} as many would expect. However, others say any correlation (let alone causation) is not found in the data.{{cite book|url=https://www.ncbi.nlm.nih.gov/books/NBK316511/|title=Chapter 3The effect of reduced street lighting on crime and road traffic injuries at night in England and Wales: a controlled interrupted time series analysis|chapter=The effect of reduced street lighting on crime and road traffic injuries at night in England and Wales: A controlled interrupted time series analysis |date=September 2015 |publisher=NIHR Journals Library }}{{cite web|url=https://popcenter.asu.edu/content/improving-street-lighting-reduce-crime-residential-areas-page-2|title=How Might Improved Lighting Affect Crime?|date=2 March 2016 |quote=...the main implication of this research is that although improved street lighting might displace crime into nearby neighborhoods, it is just as likely to reduce crime in these neighborhoods because of a diffusion of benefits.}}{{cite news|url=https://www.bloomberg.com/news/articles/2014-02-12/street-lights-and-crime-a-seemingly-endless-debate|title=Street Lights and Crime: A Seemingly Endless Debate|publisher=Bloomberg News |date=12 February 2014 }}

Towns, cities, and villages can use the unique locations provided by lampposts to hang decorative or commemorative banners. Many communities in the US use lampposts as a tool for fundraising via lamppost banner sponsorship programs first designed by a US-based lamppost banner manufacturer.[http://www.projectgraphics.com/light-pole-banner-sponsorship-guide.php "Lamppost Banner Sponsorship Programs"] {{webarchive|url=https://web.archive.org/web/20111225035206/http://www.projectgraphics.com/light-pole-banner-sponsorship-guide.php |date=25 December 2011 }}

The major criticisms of street lighting are that it can actually cause accidents if misused{{Citation needed|date=April 2024}}, and cause light pollution.

There are three optical phenomena that need to be recognized in streetlight installations.

• The loss of night vision because of the accommodation reflex of drivers' eyes is the greatest danger. As drivers emerge from an unlighted area into a pool of light from a streetlight their pupils quickly constrict to adjust to the brighter light, but as they leave the pool of light the dilation of their pupils to adjust to the dimmer light is much slower, so they are driving with impaired vision. Additionally, research has shown that pupil reflexes are more pronounced and post-light recovery takes longer after exposure to blue light compared to red light. This poses a continually increasing risk as blue-rich light sources become more common in roadway lighting and vehicle headlights.{{Cite journal |last1=Lei |first1=Shaobo |last2=Goltz |first2=Herbert C. |last3=Chandrakumar |first3=Mano |last4=Wong |first4=Agnes M. F. |date=2014-07-21 |title=Full-field Chromatic Pupillometry for the Assessment of the Postillumination Pupil Response Driven by Melanopsin-Containing Retinal Ganglion Cells |url=http://dx.doi.org/10.1167/iovs.14-14103 |journal=Investigative Ophthalmology & Visual Science |volume=55 |issue=7 |pages=4496–4903 |doi=10.1167/iovs.14-14103 |pmid=24925879 |issn=1552-5783|url-access=subscription }}{{Cite journal |last1=Lei |first1=Shaobo |last2=Goltz |first2=Herbert C. |last3=Chen |first3=Xingqiao |last4=Zivcevska |first4=Marija |last5=Wong |first5=Agnes M. F. |date=2017-03-06 |title=The Relation Between Light-Induced Lacrimation and the Melanopsin-Driven Postillumination Pupil Response |journal=Investigative Ophthalmology & Visual Science |language=en |volume=58 |issue=3 |pages=1449–1454 |doi=10.1167/iovs.16-21285 |pmid=28264100 |issn=1552-5783|doi-access=free }} As a person gets older, the eye's recovery speed gets slower, so driving time and distance under impaired vision increases.
• The loss of night vision due to visual adaptation of retinal cells to a higher luminance level provided by streetlights. Once an individual leaves the illuminated area their retinal cells require adaptation time before they are sensitive to objects and motion under the lower luminance levels of unlit areas.
• Oncoming headlights are more visible against a black background than a grey one. The contrast creates greater awareness of the oncoming vehicle.
• Stray voltage is also a concern in many cities. Stray voltage can accidentally electrify lampposts and has the potential to injure or kill anyone who comes into contact with the post.{{cite web | title = Stray Voltage Still on the Loose | publisher = Scienceline | date = 4 August 2006 | url = http://scienceline.org/2006/08/04/physics-grant-manholes/ | access-date = 19 July 2008 | url-status = live | archive-url = https://web.archive.org/web/20080622162955/http://scienceline.org/2006/08/04/physics-grant-manholes/ | archive-date = 22 June 2008 }}

There are also physical dangers to the posts of streetlamps, other than children climbing them for recreational purposes. Streetlight stanchions (lampposts) pose a collision risk to motorists and pedestrians, particularly those affected by poor eyesight or under the influence of alcohol. This can be reduced by designing them to break away when hit (known as frangible, collapsible, or passively safe supports), protecting them by guardrails, or marking the lower portions to increase their visibility. High winds or accumulated metal fatigue also occasionally topple streetlights.

Light pollution can hide the stars and interfere with astronomy. In settings near astronomical telescopes and observatories, low-pressure sodium lamps may be used. These lamps are advantageous over other lamps such as mercury and metal halide lamps because low-pressure sodium lamps emit lower intensity, monochromatic light. Observatories can filter the sodium wavelength out of their observations and virtually eliminate the interference from nearby urban lighting. Full cutoff streetlights also reduce light pollution by reducing the amount of light that is directed at the sky, which also improves the luminous efficiency of the light.

File:No street lighting Leeds July 2014.jpg, UK indicating part-night lighting, meant to save energy and reduce light pollution.]]

Streetlights can impact biodiversity and ecosystems—for instance, disrupting the migration of some nocturnally migrating bird species.{{Cite journal|last1=Cabrera-Cruz|first1=Sergio A.|last2=Smolinsky|first2=Jaclyn A.|last3=Buler|first3=Jeffrey J.|date=2018-02-19|title=Light pollution is greatest within migration passage areas for nocturnally-migrating birds around the world|journal=Scientific Reports|language=en|volume=8|issue=1|pages=3261|doi=10.1038/s41598-018-21577-6|issn=2045-2322|pmc=5818656|pmid=29459760|bibcode=2018NatSR...8.3261C }} In the Netherlands, Philips found that birds can get disoriented by the red wavelengths in street lighting, and in response developed alternative lighting that only emit in the green and blue wavelengths of the visible spectrum. The lamps were installed on Ameland in a small-scale test. If successful, the technology could be used on ships and offshore installations to avoid luring birds towards the open sea at night.{{citation |url=https://www.electronicsweekly.com/blogs/led-luminaries/birds-get-migration-friendly-streetlights-2017-05/ |date=10 May 2017 |last=Bush |first=Steve |access-date=21 August 2020 |title=Birds get migration-friendly streetlights |via=Electronics Weekly}} Bats can be negatively impacted by streetlights,{{Cite journal|date=2015-05-01|title=Impacts of artificial lighting on bats: a review of challenges and solutions|url=https://www.sciencedirect.com/science/article/abs/pii/S1616504715000233|journal=Mammalian Biology|language=en|volume=80|issue=3|pages=213–219|doi=10.1016/j.mambio.2015.02.004|issn=1616-5047|last1=Stone|first1=Emma Louise|last2=Harris|first2=Stephen|last3=Jones|first3=Gareth|url-access=subscription}} with evidence showing that red light can be least harmful.{{Cite journal|last1=Spoelstra|first1=Kamiel|last2=van Grunsven|first2=Roy H. A.|last3=Ramakers|first3=Jip J. C.|last4=Ferguson|first4=Kim B.|last5=Raap|first5=Thomas|last6=Donners|first6=Maurice|last7=Veenendaal|first7=Elmar M.|last8=Visser|first8=Marcel E.|date=2017-05-31|title=Response of bats to light with different spectra: light-shy and agile bat presence is affected by white and green, but not red light|journal=Proceedings of the Royal Society B: Biological Sciences|volume=284|issue=1855|pages=20170075|doi=10.1098/rspb.2017.0075|pmc=5454258|pmid=28566484}} As a result, some areas have installed red LED streetlights to minimise disruption to bats.{{Cite news|date=2019-08-31|title=Bat-friendly street lights for Worcestershire crossing|language=en-GB|publisher=BBC News|url=https://www.bbc.com/news/uk-england-hereford-worcester-49534621|access-date=2021-09-19}}{{Cite web|title=This Bat-Friendly Town Turned the Night Red|url=https://www.treehugger.com/worlds-first-bat-friendly-town-turns-night-red-4868381|access-date=2021-09-19|website=Treehugger|language=en}} A study published in Science Advances reported that streetlights in southern England had detrimental impacts on local insect populations.{{Cite journal|last1=Boyes|first1=Douglas H.|last2=Evans|first2=Darren M.|last3=Fox|first3=Richard|last4=Parsons|first4=Mark S.|last5=Pocock|first5=Michael J. O.|date=August 2021|title=Street lighting has detrimental impacts on local insect populations|journal=Science Advances|volume=7|issue=35|language=EN|doi=10.1126/sciadv.abi8322|pmc=8386932|pmid=34433571|bibcode=2021SciA....7.8322B }} Streetlights can also impact plant growth and the number of insects that depend on plants for food.{{Cite web |title=Light pollution shown to affect plant growth, food webs |url=https://www.sciencedaily.com/releases/2015/03/150316093003.htm |access-date=2022-11-07 |website=ScienceDaily |language=en}}

As of 2017, globally 70% of all electricity was generated by burning fossil fuels,{{cite web|title=Global energy demand grew by 2.1% in 2017, and carbon emissions rose for the first time since 2014|url=https://www.iea.org/newsroom/news/2018/march/global-energy-demand-grew-by-21-in-2017-and-carbon-emissions-rose-for-the-firs.html|website=International Energy Association|access-date=11 May 2018}} a source of air pollution and greenhouse gases, and also globally there are approximately 300 million streetlights using that electricity.{{cite web |url=http://www.researchandmarkets.com/reports/2763639/global_led_and_smart_street_lighting_market |title=Global LED and Smart Street Lighting: Market Forecast (2017–2027) |access-date=18 February 2016 |url-status=live |archive-url=https://web.archive.org/web/20160225003719/http://www.researchandmarkets.com/reports/2763639/global_led_and_smart_street_lighting_market |archive-date=25 February 2016}} Cities are exploring more efficient energy use, reducing streetlight power consumption by dimming lights during off-peak hours and switching to LED streetlights which illuminate a smaller area to a lower level of luminance.{{cite web |url=http://www.edmonton.ca/transportation/on_your_streets/street-lighting.aspx |title=Street Lighting :: City of Edmonton |access-date=15 February 2016 |url-status=live |archive-url=https://web.archive.org/web/20160222090339/http://www.edmonton.ca/transportation/on_your_streets/street-lighting.aspx |archive-date=22 February 2016}} Many councils are using a part-night lighting scheme to turn off lighting at quieter times of night. This is typically midnight to 5:30 AM, as seen by the sign on the right. There have, however, been questions about the impact on crime rates. Typical collector road lighting in New York State costs $6,400/mile/year for high pressure sodium at 8.5 kW/mile or $4,000 for light-emitting diode luminaires at 5.4 kW/mile.Humayun Kabir, John D. Bullough, Leora C. Radetsky. "[http://www.nyserda.ny.gov/-/media/Files/Publications/Research/Transportation/Sustainable-Roadway-Lighting-Seminars.pdf Sustainable Roadway Lighting Seminar Final Report] {{webarchive|url=https://web.archive.org/web/20170126112358/https://www.nyserda.ny.gov/-/media/Files/Publications/Research/Transportation/Sustainable-Roadway-Lighting-Seminars.pdf |date=26 January 2017 }}" New York State Energy Research and Development Authority, July 2014, p.27 Improvements can be made by optimising directionality and shape, however. Transitioning to wide angle lights enabled the doubling of distance between streetlights in Flanders from 45 m to 90 m, cutting annual street lighting electricity expenditures to €9 million for the 2,150 km long network that was retrofitted, corresponding to ca. €4,186/km.{{citation |url=https://www.nieuwsblad.be/cnt/g7tdhfvt |language=nl |date=23 March 2005 |title=Straatverlichting kost 9 miljoen euro |access-date=21 August 2020}}

{{More citations needed section|small=y|date=March 2017}}

A number of street light control systems have been developed to control and reduce energy consumption of a town's public lighting system. These range from controlling a circuit of street lights and/or individual lights with specific ballasts and network operating protocols. These may include sending and receiving instructions via separate data networks, at high frequency over the top of the low voltage supply or wireless.{{cite journal|last=Domingo-Perez|first=Francisco|title=Low-rate wireless personal area networks applied to street lighting|journal=Lighting Research & Technology|date=February 2013|volume=45|issue=1|pages=90–101|doi=10.1177/1477153511431129|s2cid=111175671}}

Street light controllers are smarter versions of the mechanical or electronic timers previously used for street light ON-OFF operation. They come with energy conservation options like twilight saving, staggering or dimming. Many street light controllers come with an astronomical clock for a particular location or a Global Positioning System (GPS) connection to give the best ON-OFF time and energy saving.

File:INDO Light with telecell.jpg

Some intelligent street light controllers also come with Global System for Mobile Communications (GSM), Radio frequency (RF) or General Packet Radio Service (GPRS) communication, user adjusted according to latitude and longitude (low cost type), for better street light management and maintenance. Many street light controllers also come with traffic sensors to manage the lux level of the lamp according to the traffic and to save energy by decreasing lux when there is no traffic. The United States, Canada, India, and many other countries have started introducing street light controllers to their road lighting for energy conservation, street light management and maintenance purpose.

Street light controllers can be expensive in comparison with normal timers, and can cost between $100 and $2,500, but most of them return the investment between 6 months and 2 years. As the equipment's lifetime is 7 to 10 years, it saves energy and cost after the initial investment has been recouped.

A number of companies are now manufacturing intelligent street lighting that adjust light output based on usage and occupancy, i.e. automating classification of pedestrian versus cyclist, versus automobile, sensing also velocity of movement and illuminating a certain number of streetlights ahead and fewer behind, depending on velocity of movement. Also, the lights adjust depending on road conditions, for example, snow produces more reflectance therefore reduced light is required.

There are three distinct main uses of street lights, each requiring different types of lights and placement. Using the wrong types of lights can make the situation worse by compromising visibility or safety.

File:The Plaza at sunset, Samaipata, Bolivia.jpg]]

A modest steady light at the intersection of two roads is an aid to navigation because it helps a driver see the location of a side road as they come closer to it, so that they can adjust their braking and know exactly where to turn if they intend to leave the main road or see vehicles or pedestrians. A beacon light's function is to say "here I am" and even a dim light provides enough contrast against the dark night to serve the purpose. To prevent the dangers caused by a car driving through a pool of light, a beacon light must never shine onto the main road, and not brightly onto the side road. In residential areas, this is usually the only appropriate lighting, and it has the bonus side effect of providing spill lighting onto any sidewalk there for the benefit of pedestrians. On Interstate highways, this purpose is commonly served by placing reflectors at the sides of the road.

{{Further|Pedestrian crossing#Lighting}}

File:Highway 401 Night Lapse Busy.jpg in Ontario, Canada]]

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Because of the dangers discussed above, roadway lights are properly used sparingly and only when a particular situation justifies increasing the risk. This usually involves an intersection with several turning movements and much signage, situations where drivers must take in much information quickly that is not in the headlights' beam. In these situations (a freeway junction or exit ramp), the intersection may be lit so that drivers can quickly see all hazards, and a well-designed plan will have gradually increasing lighting for approximately a quarter of a minute before the intersection and gradually decreasing lighting after it. The main stretches of highways remain unlighted to preserve the driver's night vision and increase the visibility of oncoming headlights. If there is a sharp curve where headlights will not illuminate the road, a light on the outside of the curve is often justified.

If it is desired to light a roadway (perhaps due to heavy and fast multi-lane traffic), to avoid the dangers of casual placement of street lights, it should not be lit intermittently since this requires repeated eye readjustment, which causes eyestrain and temporary blindness when entering and leaving light pools. In this case, the system is designed to eliminate the need for headlights. This is usually achieved with bright lights placed on high poles at close, regular intervals so that there is consistent light along the route. The lighting goes from curb to curb.

File:Cycle path on The Roundway Tottenham London England.jpg with street lights in London]]

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File:Manworkingonastreetlamp-tokyo-area-2006-11-7.jpg

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Policies that encourage utility cycling have been proposed and implemented, including lighting bike paths to increase safety at night.

Lights similar to street lights are used on railway platforms at train stations in the open air. Their purpose is similar to that of beacon lights: they help a train driver see the location of a station at night as the train comes closer to it, so that the driver can adjust the braking and know exactly where to stop. A train station light must never shine directly onto the tracks, and has the bonus side effect of providing spill lighting onto any platform for the benefit of passengers waiting there.

File:New York City Street Light Status.jpg

Street lighting systems require ongoing maintenance, which can be classified as either reactive or preventative. Reactive maintenance is a direct response to a lighting failure, such as replacing a discharge lamp after it has failed or replacing an entire lighting unit after it has been hit by a vehicle. Preventative maintenance is the scheduled replacement of lighting components, for example, replacing all the discharge lamps in an area of the city when they have reached 85% of their expected life. Maintenance may be undertaken by the lighting owners or by a contractor.

In the United Kingdom, the Roads Liaison Group has issued a Code of Practice recommending specific reactive and preventative maintenance procedures.{{cite web|url=http://www.ukroadsliaisongroup.org/en/guidance/codes-of-practice.cfm|title=Codes of Practice|first=Justin|last=Ward|website=ukroadsliaisongroup.org}}

Some street lights in New York City have an orange or red light on top of the luminaire (light fixture) or a red light attached to the lamppost. This indicates that near to this lighting pole or in the same intersection, there is a fire alarm pull box.{{cite web |url=http://forgotten-ny.com/2011/03/breaking-the-rules-odd-placements-of-fire-alarm-indicators/ |title=BREAKING THE RULES. Odd placements of fire alarm indicators – Forgotten New York |date=25 March 2011 |access-date=22 April 2016 |url-status=live |archive-url=https://web.archive.org/web/20160330084143/http://forgotten-ny.com/2011/03/breaking-the-rules-odd-placements-of-fire-alarm-indicators/ |archive-date=30 March 2016}} Other street lights have a small red light next to the street light bulb; when the small light flashes, it indicates an issue with the electric current.{{cite web |url=http://www.nyc.gov/html/dot/html/infrastructure/streetlights.shtml |title=NYC DOT – Street Lights |access-date=22 April 2016 |url-status=live |archive-url=https://web.archive.org/web/20160425113835/http://www.nyc.gov/html/dot/html/infrastructure/streetlights.shtml |archive-date=25 April 2016}}

Street lights are the basic example of public goods, which are nonexcludable and nonrival. This means that the producer cannot prevent those who do not pay from consuming, and the consumption of one person cannot prevent the consumption of another person. This becomes a problem for governments, because no private company would have the incentive to produce street lights, which is why most governments are in charge of placing and maintaining street lights. For example, in Armenia, building and maintaining infrastructure is the duty of local self-governance.{{cite web |url=http://www.parliament.am/legislation.php?sel=show&ID=1305&lang=eng |title=THE LAW OF THE REPUBLIC OF ARMENIA ON LOCAL SELF-GOVERNMENT |access-date=19 December 2021 }}

File:Street light-hrad bratislava.JPG|A historical Slovak lamppost

File:3lamps.jpg|Polish street lights from the 1930s

File:Straßenlaterne.JPG|German streetlight at night

File:2014-10-30 11 28 51 Old street lamp on Fireside Avenue in Ewing, New Jersey.JPG|Street light from the 1950s attached to a utility pole in New Jersey

File:Lyktstolpar - Gatubelysning - Ystad-2021.jpg|Streetlights in Ystad, 2021

File:Seututie 110 Piikkiö.jpg|Streetlights in Finnish regional road

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• Charging station
• Floodlight
• Gas lighting
• History of street lighting in the United States
• Intelligent street lighting
• Lighting-up time
• Light pollution
• List of light sources
• Solar street light
• Street furniture
• Street light interference

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{{Reflist}}

• {{cite book |last=Fierro |first=Alfred |year=1996 |title=Histoire et dictionnaire de Paris |publisher=Robert Laffont |isbn=978-2-221-07862-4}}
• {{cite book |last=Lobsey |first=Ian |year=1988 |title=City of light |publisher=Peel-Cunningham County Council |isbn=978-0731657780}}

• {{cite book |last1=van Bommel |first1=Wout |date=2015 |title=Road Lighting Fundamentals, Technology and Application |publisher=Springer |isbn=9783319114651|doi=10.1007/978-3-319-11466-8 }}

{{commons category|Street lights}}

• [http://www.streetlightonline.co.uk An enthusiast's guide to street lighting – including many close-up photographs of UK street lighting equipment, as well as information on installations through the ages. (UK)]
• [https://web.archive.org/web/20100213054349/http://www.panasonic.net/pes/products/env/windseagull/img/image13.jpg Example Installation of Integrated Renewable Power in Street Lighting], an example of a street lighting system with integrated solar and wind generator from Panasonic/Matsushita
• [http://www.lrc.rpi.edu/programs/transportation/index.asp Transportation Lighting at the Lighting Research Center]
• [http://lightingresearch.group.shef.ac.uk/index.html Lighting Research at the University of Sheffield]

{{Artificial light sources}}

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Category:Light fixtures

Category:Light pollution

Category:Street furniture

Category:Urban planning