Introduction One of the most serious challenges in the world today is the scarcity of energy resources. For example, oil prices have been on the upward trend in the last few decades, due to the decrease in the number of oil deposits. Electricity is another important source of energy and its level of production has gone down considerably in many countries due to environmental degradation that has affected water resources. As the world grapples with the scarcity of energy resources, scientists are now focusing on other energy sources such as solar energy which has not been properly exploited. The scarcity of energy resources has led to changes in technological trends such that electronic gadgets that are now being invented are designed in a manner that makes them consume little energy. Apart from using electricity to power electronics, solar energy may be used as an alternative source of energy for electronics. Most machines can now use solar energy and traffic lights are not an exception. This paper discusses the use of solar energy in traffic lights. “Traffic lights refer to signaling devices positioned at road intersections, pedestrian crossings, and other locations to control competing flows of traffic” (Orcuitt 12). These lights are commonly utilized to control and coordinate traffic in cities and big towns which have busy road and railway networks. Traffic Lights Traffic lights were probably introduced in 1868 in Britain and they were introduced by an engineer called P. Knight. These lights were used within the parliament in the city of London. However, the present traffic lights were indeed invented by Americans. The Americans started using traffic lights in 1912. “Salt Lake City is where the traffic lights were first used to manage the flow of traffic” (Orcuitt 56). Automatic traffic lights were first used in Houston and Texas. As the use of traffic lights gained prominence, various designs of traffic lights were invented to meet the road safety needs of various countries. Today many countries are using traffic lights on their major roads. Solar Technology Solar energy was introduced several centuries ago and it is still being used even now. “The earliest evidence of Passive Solar Design can be seen in Architecture of the early civilizations of Egypt, Mesopotamia, and the highly developed ancient cultures of South America. (Solar Energy International 68)” The photoelectric effect was first discovered and used by Henry Becquerel. This marked the origin of solar cells which are used today. Charles Fritts later on in the nineteenth century applied metalized selenium to make vacuum photocells. After this photovoltaic technology was introduced and it has been improved and utilized in some aerospace industries. “Photovoltaic technology is referred to as the process by which electric power is generated from sunlight” (Dunlop 268). Further modifications on photovoltaic cells have been made by engineers and they are today widely recognized and used. How a Solar Traffic Light Works Photovoltaic System Photovoltaic cells function using the following mechanisms. First, “Photovoltaic modules(solar panels) often have a sheet of glass on the front (sun up) side, allowing light to pass while protecting the semiconductor wafers from abrasion and impact due to wind-