www.iaset.us editor@iaset.us PHOTOVOLTAIC (PV) SOLARSYSTEM SIZING FOR OFF GRID SOLAR HOME SYSTEMS SEBASTIAN WAITA & BERNARD ADUDA Department of Physics, University of Nairobi, Nairobi, Kenya ABSTRACT The sun releases tremendous amount of energy, which if harnessed would provide all energy needs of mankind. One of the strategies to trap this immense energy is the use of solar modules/panels. However, these solar modules need to be properly sized and installed to be able to function and generate electricity optimally. The successful installation of an off grid Photovoltaic (PV) solar system is a process that begins with a site visit to the area of installation, the determination of the client’s energy needs, installation of the solar PV system, commissioning of the installed solar system and ends with user training. Every step is critical for it determines the final performance of the solar system and hence the delicate balance between a satisfied or unsatisfied client. However, the system sizing step tends to attract more attention for it determines the system size and the matching of the balance of system components and so if this is not properly done, then the entire system may not perform as intended. Most documented sizing methods tend to be too complicated and require significant computer knowledge in simulation, modeling and even programming. For practical purposes, many designers and PV installers, especially in developing countries have basic education may not be well equipped for these complicated sizing methods. Furthermore, very few have been professionally trained in PV solar system Sizing and although there are commercially available sizing software’s, they are too expensive for majority of the people and even if available, they are too complicated for them.In actual sizing therefore, most untrained PV technicians use mere estimates that may not be appropriate for the outcome, more often than not is disappointing. We present a simple sizing method that can easily be learned andapplied in a simple calculation, for example in a simple excels sheet formulas for easier sizing of PV systems. The method is recommended for adoption in developing countries for faster dissemination of professional PV services in system sizing. KEYWORDS: Installation, Method, Off-Grid, Photovoltaic (PV), Sizing INTRODUCTION Energy is very key to any country and is one of the key determinants of development in any country. Energy shortage definitely undermines efforts for social and economic development. Africa and more specifically, sub- Saharan Africa has been considered as lagging behind in development compared to the rest of the world and one of the components of development to consider is the availability as well as affordability of energy. The population explosion in Africa is not well matched with its rising energy demand. For example, between 2000 and 2012, the energy demand for sub-Saharan Africa grew by 45 % (which is only 4 % of the world’s total energy demand) although the region accommodates 13 % of the world population [1]. Yet, this energy demand can be significantly reduced by exploiting the continents vast renewable energy resource base. Kenya is one of the countries in the sub-Saharan Africa which has high potential for renewable energy, especially International Journal of Applied and Natural Sciences (IJANS) ISSN(P): 2319-4014; ISSN(E): 2319-4022 Vol. 5, Issue 5, Aug – Sep 2016; 73-78 © IASET