Photovoltaic engineering e-learning applications developed for remote laboratory experimentation systems

Int J Energy Environ Eng (2014) 5:78 DOI 10.1007/s40095-014-0078-4 ORIGINAL RESEARCH Photovoltaic engineering e-learning applications developed for remote laboratory experimentation systems Petros J. Axaopoulos • Emmanouil D. Fylladitakis Received: 9 January 2014 / Accepted: 3 March 2014 / Published online: 18 March 2014  The Author(s) 2014. This article is published with open access at Springerlink.com Abstract In this paper, a functional remote experimentation system tested for long-term use stability and under real weather conditions is presented. The proposed system offers the ability to students and anyone interested to remotely conduct experiments with a real PV module from anywhere on the planet, as long as an Internet connection is available. This innovative system is based on a 55Wp photovoltaic panel installed facing south on the roof of a lab, which is installed on a motorized mount allowing it to alter its tilt angle from 0 to 90. A camera offers continuous live video streaming of the test site. In order to demonstrate a portion of the aforementioned system’s potential, a set of five proposed educational experiments and exercises that may be performed through the Internet is being comprehensively demonstrated in this paper. Each test creates an I–V and a P–I chart, as well as a TXT file with the test data, which is automatically stored for future use. The procedure only takes a few seconds to complete and the extracted data can then be studied and analyzed in due time, allowing the student to contemplate on the results and put theoretical knowledge into practice. Remote access to a renewable energy lab opens new ways to the education of photovoltaics by offering the students a feeling of direct experience with actual PV equipment and is a process P. J. Axaopoulos Department of Energy Technology, Technological Educational Institute (TEI) of Athens, Ag. Spyridonos, 12210 Aegaleo, Greece E. D. Fylladitakis (&) Electronic and Computer Engineering Department, School of Engineering and Design, Brunel University, Uxbridge, London, UK e-mail: exceptionally useful for part-time learners, distance learners, as well as students with disabilities. Keywords Photovoltaic engineering education  Remote laboratory  PV module  Computer application  Distance education  e-learning Introduction The sun is known to be one of the most important sources of renewable energy, and this energy may be captured almost anywhere on the planet and converted directly into electric power through photovoltaic (PV) panels [1]. Favorable policies, technological advancements and the lowering production costs led to the rapid growth of PV systems over the last decade all around the world. In a few countries the installed PV power multiplied within a single year, as for example in Korea and Spain where it increased six and five times, respectively, from 2007 to 2008 [2]. However, technical specifications provided by PV module manufacturers are always presented at standard test conditions (STC) and are considered insufficient to perform proper modeling [3], with scientists reporting an overestimation of the generation by up to 40 % when performing studies by using the STC figures [4]. Therefore, solar energy engineers need to be capable of extracting the real V–I characteristics of any PV module in order to accurately assess a system’s performance and troubleshoot potential problems. Even though theoretical study is an important aspect of education, in engineering education it is well known that it should be combined with experimentation in order to help the student to become capable of putting the theory into practice [5]. Laboratory experiments are fundamental for 123 78 Page 2 of 10 engineering courses, in order for the students to develop a ‘‘feel for engineering’’ [6]; however, this is not always possible, as access to equipment is limited by a great number of factors, such as the location of the students, the climatic conditions, as well as time and financial constraints. Nevertheless, technology and the Internet can prove to be very valuable tools for current and future engineers, who must today possess a large number of skills and a high level of expertise in order to become successful entrepreneurs [7]. Even though the first Internet-based solar engineering education applications were developed well over a decade ago, technological limitations and the lack of widespread Internet accessibility limited their adoption rates [8]. Still, in advanced countries where today the vast majority of the population has Internet access, Internetbased engineering education is now taking leaping steps forward. Remote access to laboratories offers many advantages to engineering students and academics alike by allowing access at any time of the day from any part of the world, as long as there is access to the Internet. Some of these advantages are the capability of distance education, the possibility to access laboratories around the globe and take live and/or recorded readings at any time and the opportunity that handicapped students would have to participate in laboratory coursework. Remote laboratory experimentation offers high quality learning experiences in science and engineering education, while adding flexibility, especially in terms of time and special needs [9]. Furthermore, remote laboratories are especially useful when conducting experimental studies with systems that are inaccessible, too large and/or too expensive for physical measurements by students, while they offer similar or greater educational benefits [10]. During the past decade, there have been several papers describing the development of remote access laboratories for specific experiments. Yeung and Huang [11] described the architecture of a system for DC motor controls using a web interface; Restino et al. [12] developed a remotely accessible laboratory setup for the mechanical characterization of materials; Lazar and Carari [13] presented a remotely accessible laboratory for the education of network control systems, and Bellmunt et al. [14] describe the development of a PLC programming course via a remote laboratory system. However, to the best of our knowledge, the development of remote laboratory applications to this date has been limited to indoor sessions only, the equipment of which frequently is easily accessible to everyone attending the course. The renewable energy laboratory of the Technological Educational Institute (TEI) of Athens has developed simulation software for educational use [15, 16] and today offers remote access to an experimentation module which 123 Int J Energy Environ Eng (2014) 5:78 is installed on the roof of the building. The experimentation module consists of a 55Wp PV panel installed on singleaxis motorized mount, allowing any user to access the web server from the Internet and perform real-time experiments at different tilt angles, extracting the I–V characteristic of the insta (...truncated)