LED street lights:

http://fleetowner.com

I was interested about street lights and how they should be in urban areas and I found information about LED street lights which are environmentally and economically sustainable.According to Stroud (2010) LED lights are made from light points instead of wire in old lights which can make the light hot.This factor could considerably help to reduce energy usage.These lightes could last more than old lights. I also watched a video that showed before and after using lights in a certain streets. The light is white with better quality in order to see objects and distance at night. Furthermore because of the better quality the number of lights can be reduced to compare with old lights. These lights also could be used with solar batteries as second source of energy (Chen and Liu and Yau and Chun 2008).
sourses:
 -  Chen,P and  Liu,Y and Yau,Y and  Chun Lee,H 2008,Development of an Energy Efficient Street Light Driving System, Sustainable Energy Technologies,PP761 - 764.
 -IFI CLAIMS Patent Services 2012, Led street light, United State, Accessed 18 May,
 https://www.youtube.com/watch?v=6ZbeDoE8488