Sydney’s lights will soon have a dimmer too.
None, if it’s a City of Sydney engineer. In the future there won’t be any bulbs to change.
The city’s transforming its 6,450 streetlights by replacing bulbs, or metal halide lamps, with new LED (light emitting diode) units.
Developed in the 1960s, metal halides produce light when an electric arc passes through vapourised mercury and metal halide gases. They produce a bright, white light but require changing every four years and consume a lot of energy.
In contrast, Sydney’s incoming LED streetlights are expected to last 15 years, are better for the environment, and even let engineers manage them using a smartphone.
“We’re hoping to save 2,100 megawatts of electricity per year, which is approximately 2,250 tonnes of CO2 per year,” explained Paul Gowans, principal engineer at City of Sydney.
Once completed, the project is expected to reduce the City of Sydney’s annual energy and maintenance costs by 40 percent, or approximately $800,000.
The maintenance savings are due in part to a five-yearly cleaning cycle for the LEDs. No other servicing is required, explained George Verghese, GE Regional Sales Manager, A&NZ.
“Every two to three years, the council has had to get a cherry-picker, have traffic management in place and change lamps,” Mr Verghese said. “Now, they don’t have to do any lamp changes because LED lamps work for approximately 50,000 hours, or 11.7 years.”
The new streetlights also offer a feature not available with the existing metal halides. The council can now monitor and dynamically manage light levels from an office, headquarters or even a smartphone.
“In Martin Place we’ve got 12 lights controlled by smart controls, which allows us to adjust lighting levels according to environmental conditions,” Mr Gowans said.
The technology reports on the streetlight’s operating wattage, if there’s been a failure, what that failure was and how it happened.
Meanwhile, the council has the option of using different LEDs in different areas. Before installation begins, a team determines if the LEDs will deliver similar lighting levels to the existing streetlights.
A design team then draws the entire system and submits a design with LEDs before the units are installed. Functional lights are used on the streets with LEDs consuming 158 to 257 watts.
“In the parks we’re using a more decorative model. They range from 39 watts to 66 watts and replace 70 watt metal halides,” Mr Gowans said.