StreetLightNews

BBC News is reporting that more than 15,000 street light columns, or over 85% of the stock, will be replaced in Redcar and Cleveland, UK. The existing columns have passed their 25-year life expectancy, and another 2,500 street lights will be added over the next few years in order to raise the standard of the cities’ public lighting. It has been established that the distance between the existing lights is too large, so the additional 2,500 street lights will ensure better lid roads and improve safety for both motorists, bicyclists and pedestrians.

GE has recently decided to cease manufacturing of the relatively inefficient Low Pressure Sodium lamps. This follows a general market trend with a shift towards the newer HID technology with e.g. High Pressure Sodium lamps. These have a better color rendition and whiter output, which is believed to prevent accidents, improve reaction times and reduce crime. Furthermore, the lamps are more efficient, enabling fewer lights, less maintenance and compliance with dark skies recommendations. Read the full article at the Institution of Lighting Engineeers’ website…

Replacing standard street light with new high output LEDs will save 50% energy and they will last more than 10 years. They are maintenance-free, contain no hazardous material such as gases or mercury, and they are dark sky compliant, meaning that their light is focused on the area where it is needed, and not wasted into the night sky.
At the upcoming American Public Works Association event in San Antonio, September 9-12, these new LEDs will be showcased by the company inventing the new effective street light - IntenCity Ligthing.
The new high output LED uses only 75 watts, but produces 3200 lumens. See more here…

American-based Civil Twilight Collective works with exploring how our built, urban environment can apply natural phenomena in a practical way. One of their ideas is to involve the lunar cycle when lighting up the streets.
The lunar-resonant streetlights will sense and respond to the moon, dimming and brighting according to the particular phase the moon is in. The Civil Twilight Collective states on their website that the project will save energy and lower light pollution, giving urban dwellers a better experience of the lunar cycle.
Great idea, but I wonder if it is efficient enough. Each luminaire is equipped with a photosensor, so I suppose they can adjust for clouds. And the cost of equipping every street light with a photocell, dimmer and LED cluster? Must be high.

In a New Yorker article, David Owen describes how dark skies are increasingly difficult to find. He states that most Americans are unable to see the Milky Way where they live. Obviously, the stars have not become dimmer, but excess light increasingly prevents us from seing the entire beauty of the skies at night.
According to Bortle’s Dark-Sky Scale, invented by John E. Bortle in 2001, nighttime skies rated 1 are as dark as in Galileo’s time. At the other end of the scale is New York with a dark-sky rating of 9.
But there are several ways of avoiding, or at least minimizing, the light pollution from urbanized areas. Naturally, improved street lights are a big factor in reducing the excess light. Not only through retrofitting the luminaires and bulbs, but also by controlling that the lights are turned off and posibly dimmed at the most optimal times. For more information on centralized control and dimming, see e.g. www.amplex.dk or www.streetlight-vision.com.
To read an abstract of the New Yorker-article, click here…

The International Dark-Sky Association (IDA), being very active in preserving or restoring the dark skies by eliminating light pollution, has recently introduced an ordinance for small communities, urban neighborhoods and subdivisions. The ordinance describes how outdoor night light can be effective and reasonable without polluting the surroundings with excess light.
The purpose of IDA is to minimize the effects of light pollution, including energy waste, harm to ecosystems, poor nightime ambience, reduced visibility at night and  to educate everyone about the values of quality outdoor lighting.
Read the ordinance here…

The Institution of Lighting Engineers, ILE, has an interesting website with news, upcoming events, etc. It provides information on all forms of interior and exterior lighting, including sports, road, flood, emergency, tunnel, security and festive lighting. Check out their website at http://www.ile.org.uk/

The Canadian company, Pure-Tek Earth, has designed a solar powered LED street light where the switch, converter, controller, the wiring and the solar battery fit into a metal box that is mounted on the individual street light pole.
Pure-Tek Earth describes on their website how the solution can save thousands of dollars in electrical costs and save the world from one ton of CO2 emission per light, per year.
There is no mentioning of centralized control of the street lights, so it is unclear whether this is an option. Also, the ROI is not described, perhaps because it is unreasonably long? Equipping every single street light with both solar batteries, controllers, switches, etc. must be rather costly.

In Hanoi, Vietnam, the street light installations are outdated and not very energy efficient. Also, many of the poles are placed in the center of the road where they do not do pedestrians much good.
Therefore, the plan is to change 1,000 11-meter concrete poles with 9-meter aluminum ones. Furthermore, almost 2,000 bulbs will be replaced with energy-efficient bulbs (LEDs?). If the plan is approved, the lights will be changed by 2010 for the city’s 1,000-year anniversary. Read the article…

Lighting up a city’s streets is typically the single most significant energy expenditure of the city. And only few areas require the same amount of maintenance and operation resources.
With centralized control, savings of 8-10% can be achieved, but the real savings occur when the city switches to dimming. Studies and numerous experiences show that savings of 30% and above are reached, giving a pay back time of just a few years.
Follow this link to learn more about dimming technologies by e.g. power reduction and electronic ballasts.