Solar Bud Lighting
The City of Darebin has recently supported a project by local traders to light the trees in their street with solar powered, LED (Light Emitting Diodes) lights. The result is much lower power consumption, longer life and when powered with solar panels, zero green house gas emissions. The use of solar power also means total flexibility in locating the lights, as no 240-volt power is required.
Bud lighting can a magical sparkle to trees and buildings in public places. However of all the forms of public lighting it is by far the most energy inefficient. Those little glowing bulbs are designed for long life rather than efficiency. They are very wasteful producing much more heat than light. In fact conventional bud lighting uses around 50 lumens per watt compared to about 15 lumens per watt for a standard incandescent lamp.
Recent technological developments have made it possible to use LED’s (Light Emmitting Diodes) for this form of public lighting with dramatic energy savings. LED’s are actually very well suited to this kind of application. They are an excellent high intensity point source and have potentially very long life (over 50,000 hours).
However there are obstacles to their use as bud light. LED’s generally having a narrow beam angle whereas a wide beam angle is needed for bud lights. LED need about 3 volts to operate whereas conventional bud lights operate on 12 volts. There was also the need to have tough, long life, exterior wiring and connections. The much lower power consumption also made it possible to power these LED’s with from solar panels.
Recently a small group of traders in the Melbourne suburb of Northcote completed a project to light 13 trees using solar powered, LED budlighting. The project, which is believed to be the first of its type in Australia was initiated by the Northcote Traders Association supported by Sustainability Victoria, the Darebin City Council and the Environment Shop that designed and installed the lights.
The project had been planned for years but had floundered due to power supply problems. Shop owners were uncomfortable with providing power to run the lights without compensation but putting in separate meter was not viable and running a power cable from inside the shops was difficult. Solar power provided a simple solution. Solar panels, batteries and control equipment could be mounted on the roof of the shop adjacent the trees. (More information on the solar bud lighting systems is available at www.enviroshop.com.au).
The total cost of the project was $34,000 with 13 trees being lit. This included the bud lights, solar panels, batteries, regulator, controllers, and the labour in design, construction and installation. The result was a dramatically improved streetscape using solar LED technology consuming as little as 10% of the energy that would be consumed with the conventional alternative. Plus because of the use of solar power, electrical supply and wiring problems have been solved. And of course no greenhouse gas emmissions at all.
