Street Lights & Light-Towers
We light our cities, towns and villages for similar reasons to lighthouses — to allow us navigate safely, to reduce accidents and to make us feel safer.
The first street lights that were installed in Ballyfermot would have been low pressure sodium lamps. These lights warm up slowly from pink to orange and were very efficient for the time. Slowly these were replaced by high pressure sodium lightbulbs which gave a yellow light.
There are still many sodium lights on our streets, but they’re being phased out for the more environmentally friendly LED light bulbs which give a bright white light.
How safe would you feel in a city at night with no lights ?
Kylemore Road Bridge, 1960s with elegant concrete street lights (Photo: Robert Francis)
Kylemore Avenue, Ballyfermot, 1970s with pole mounted sodium lamps. (Photo: Gerard Byrne)
Parts of a street light
The street light shown is a high pressure sodium lamp. These lamps have a yellow glow.
The photocell detects surrounding light levels and switches on when it gets dark.
In newer LED lamps, the lamp/bulb and reflector are replaced with an LED module and reflector.
Bonus knowledge on street lights
(for the very interested)
With thanks to Nicola O’Shea, Senior Executive Engineer at Dublin City Council, Public Lighting & Electrical Services for information on Dublin streetlights.
Light Towers
Light towers, or “moonlight towers” as some people call them, were an early alternative idea of how cities might be lit at night. Rather than many individual lights (like our street lights), a few incredibly tall super-bright lamps would be placed around the city streets, illuminating all below. The first image above was planned for the city of Paris in 1882 but was never built.
In America, the idea took hold and many light towers were constructed. The second image above shows the San Jose light tower in 1885, and the third image shows a light tower in Detroit city. By 1888, Detroit had 122 light towers, each about 50 metres high, but only thirty years later the city removed the tall light towers and installed standard street lights.
Today, Austin, Texas still uses a number of moonlight towers as part of its city lighting system.
Information on light towers from “Disenchanted Light; The Industrialisation of Light in the Nineteenth Century”, Wolfgang Schivelbusch, University of California Press, 1995.