Archive for August, 2007

Significant savings achieved on centralized control in Turkish city

Thursday, August 2nd, 2007

The Danish company, Amplex, has released a report stating that savings of 25-30% have been achieved by centralizing street light control in a major Turkish city.
The report describes a pilot project where modules are installed in five control cabinets at representative locations in the city. Parts of the savings come from centralizing control, but the most significant savings are generated through dimming at off-peak hours. Two dim levels were established, and the lights went back full on early in the morning.
Even though the pilot showed savings of up to 32%, Amplex expects the savings to be even bigger when burn hours are optimized and when dimming is set earlier in e.g. industrial areas and on weekends. Additionally, savings are expected on maintenance and proactive bulb change. Based on the indications from the pilot, a very low ROI of 1-2 years can be expected.
Read the full executive report here…

Lights on - lights off

Thursday, August 2nd, 2007

In Wycombe, UK, it seems that the district council is having problems controlling the street light. According to the local newspaper, angry residents complain that a particular street light has been left on all day for more than five weeks, in spite of complaints from locals. A while ago, the same area had problems getting a broken light fixed, this took more than three weeks.
These cases often occur in areas where different authorities are responsible for different parts of the street light. Disagreements occur when responsiblity has to be appointed. Having a centralized control system would elimate such disputes, and could provide precise reports on the state of the street lights for the entire area.

Pilot project: Dynamic dimming

Wednesday, August 1st, 2007

In order to increase the safety of night-time driving on UK motorways, and additionally lower CO2 emissions, the Lancashire County Council decided to equip a stretch of motorway M65 with a dimmable lighting system controlled by traffic flow. The system can be dimmed with up to 30%, and is equipped with an intelligent controller and a two-way remote communication facility. Additionally, it offers individual control of luminaires, event reports and constant monitoring functions of the installation.
The project came about when lighting fixtures at a specific stretch of the motorway had to be renewed. The previous installation was controlled by photocells mounted at each feeder pillar, switching the lights on and off through a contactor. The lighting levels were constant throughout the night. The luminaires in the old installation were also emitting excess light beyond the boundaries of the highway, contributing to light pollution in the surrounding area.A replacement plan was implemented in order to link the lighting level to the traffic flow, reduce the power consumption and to monitor possible lamp defects.
Through already existing traffic counters which continuously monitor the amount of cars on the motorway, the lighting levels are adjusted to preset levels depending on the traffic flow.
With more than 3,000 cars per hour, the lighting level was kept full on. With 1,500 to 3,000 cars per hour, the lights were dimmed to 75, and with less than 1,500 cars, lights were dimmed to 50%.
The new luminaires allow for ‘soft’ switching when shifting from one level to another, avoiding sudden changes in the lighting levels. Additionally, traffic safety is judged to be increased because dimming, opposed to e.g. turning off every other light as a savings measure, provides protection from a flickering or strobing effect.The completed pilot has shown that not only has the stretch of motorway gained better lighting quality and improved control, CO2 emissions are lowered 274 tons to 129 tons through a combination of the dimming, traffic flow control and the new luminaires. Read more here…