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Design and implementation of a stand-alone photovoltaic-powered phone booth

This paper describes the design and construction of a portable solar-powered phone booth coupled with a GPRS/GSM module capable of providing reliable communication while being independent of the electrical grid and telephone land-lines. Each phone booth has a pay phone case with electrical and electronic circuits to control the phone booth's operation including its power consumption and its lighting and security systems, which are powered by photovoltaic solar energy. Furthermore, recognizing the need for a reliable and affordable communication system, the GPRS/GSM communication module is designed to connect each pay phone to the available cellular network. As a result, the system was able to operate at different locations, with cellular network coverage and suitable solar radiation. As part of the pilot study, eight phone booths were constructed, installed and tested at ESPOL University's campus (Guayaquil-Ecuador) and have been operating since 2012. The criteria for the location of each phone booth were the geographic location of the students on campus and the available solar radiation at the site. The implementation of the system has demonstrated that it can successfully operate in isolated and temporary locations. The challenges and results of this pilot study will be presented in this paper. In addition, based on the experience gained from this project, further improvements to the system will be described.