In this paper, a technical and financial study about implementation of photovoltaic (PV) powered LED (light emitting diode) system to be used as traffic lights in a principal avenue of Bogotá city was done. Traditional traffics lights were compared with the new LED system taking into account design and economical parameters. 3 different systems were studied: traditional traffic light, LED traffic light, stand alone PV-powered LED system near to support (SALED) and stand alone PV-powered modern traffic light (SAMTL). The study indicated that in our special case the best option is LED traffic light, it reduces energy consumption about 88% and after 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> year it is lees expensive than traditional system.