Solar trees

Here’s an innovative way to light up our streets and save money doing it. These solar trees, tested for four weeks in October in Vienna, Austria, provided enough light during the night-time even when the sun did not show for as much as four days in a row. Even in the gloom of our U.S. winters, there are a lot of cities that get enough sunlight to keep these lights charged.

Without having to install expensive underground wiring they save in installation costs as well as remaining portable enough to move around to where they would be needed most and they are immune to blackouts.

Of course, saving money only comes in the long run. But with the level of city expansion the U.S. goes through every year there is an abundance of opportunites to use this type of light instead of the more costly traditional street lighting. If only bureaucratic red tape could be cut to allow a new technology.

Designed by Ross Lovegrove, the lights have 10 solar panels arrayed at the top of tree-like branches, which charge built-in batteries. The batteries then power LEDs for illumination. Compared to conventional streetlights, they emit much less light pollution, because LEDs generate a very directed light. The trees also incorporate light detectors! So the lights automatically turn on at sunset and off at sunrise. Now that is smart use of technology.

Using this type of technology, cities could put LED light systems on city buildings as well as at bus stops, airport terminals, etc to cut down on carbon emissions and slash local electrical bills.

Street lighting consumed 10 percent of all the electricity used in Europe in 2006 or 2,000 billion KWh, and resulted in carbon emissions of 2,900 million ton.

The use of more energy-efficient lighting in the Austrian city of Graz, with a population of almost 300,000 saved the city 524,000 KWh of electricity and 67,200 euros [US $96,800] in 2005.