Advert

Advert

Sunday, July 24, 2011

Solar traffic lights in Johannesburg South Africa


The 2007-2008 “rolling blackouts” left South Africans living in such a fear of power cuts. Even the subsequent rolling exuberant electricity price hikes did not meet with much grumbling. As an unwelcome reminder of those dark days, many parts of Johannesburg recently suffered power failures. Though of shot duration, the cuts killed many robots (local speak for traffic lights) and caused sporadic traffic chaos.
Jo’burg drivers will have no more headaches of that sort – at least not in the busiest intersections - once the city starts using sun to power the city’s traffic lights. The city plans to spend more than R11 million to modernise traffic lights by installing solar-powered signals and remote monitoring systems at critical points.
South Africa began a pilot program for solar power traffic lights several years ago. On 1 October 2007, four pairs of solar robots went live in Cape Town. They drew their power, via batteries, from solar panels on top of poles.
The primary motivation for introducing solar robots in Johannesburg was to keep traffic flowing during power cuts and avoid chaos on the busy city roads. The 2007-2008 blackouts hit hard more than 2000 critical traffic intersections, bringing commuters to a breaking point.
On top of that, solar robots are more environmentally friendly, because they rely on a renewable energy. It is hoped that in the future the solar robots could produce extra energy to add to the national grid.
True, solar power is still expensive, more expensive than the traditional sources. Researchers are, however, hoping to push the price points down eventually. Besides, the costs should be considered in a wider context. Solar traffic lights may be more costly in themselves, but the picture changes when one calculates the cost of traffic congestion in wasted petrol, productivity losses, road accidents, exhaust emissions, deployment of traffic officers to direct traffic...
The solar traffic lights will remain connected to the grid, so in case of shady days the back-up electricity will always be there. Traffic lights across Johannesburg will also be fitted with uninterrupted power supply units to fend off interruptions in the energy supply.
Since theft and vandalism of traffic lights cost the city of Johannesburg millions of rands every year, it is also worth noting that the solar panels collecting sun’s energy for the solar light will be affixed on very tall, inaccessible poles and that the batteries will be located in a thief-proof concrete casing.
There are plan to roll out the solar traffic lights project to other major cities in South Africa in the relatively near future.

Enhanced by Zemanta

No comments: