Performance evaluation of solar photovoltaic system for energy management and environmental sustainability in Moi International Airport - Mombasa, Kenya

Abstract

As a consequence of the increasing energy demand and the climate crisis in the world, the importance of alternative sustainable energy generation techniques that are clean and cheap needs to be explored. Globally, the airport industry has recently adopted the use of green energy technologies, but their utilization in Kenya remains low. The main objective of this study was to evaluate the technical, economic, and environmental analysis of the installed pilot solar photovoltaic system at Moi International Airport, Mombasa. The specific objectives were; to determine the electrical energy consumption of the airport, to perform Modelling and simulation of the solar photovoltaic system, to carry out a techno-economic analysis of the installed solar photovoltaic system, and to determine the reduction of the greenhouse gas emissions by the generated PV model. The methodology involved data collection in the form of meter readings of energy consumed at the airport and historical PV energy output from a data logger. The technical and economic data of the installed solar plant was obtained from secondary sources. Moreover, the temperature, wind, and humidity data were collected from the Meteorological Department weather station located within the airport. A Hybrid Optimization Model for Electric Renewable (HOMER) tool was utilized for modelling, optimization, sizing, and simulation. The hybrid model was designed as per the airport's electrical energy requirement (12561 kWh). The optimum system configuration was selected based on the least Net Present Cost (NPC) and least levelized cost of Energy (LCOE). The simulation results showed that the proposed hybrid system (grid- connected PV system without batteries) had the lowest NPC and LCOE of Kshs. 2,119,157,749 and Kshs.29.45/kWh, respectively. The technical results showed that the final yield (YF), capacity utilization factor (CUF), system efficiency (ƞ), and performance ratio (PR) as 3.99, 16.6%, 12.10%, and 72.35%, respectively. Furthermore, the economic indicators were: net present value (NPV) of Kshs 81,843,034, internal rate of return (IRR) of 8.34%, discounted payback period (DPP) of 12 years, and simple payback period (SPP) of 9 years. The installation's least cost of energy was estimated to be Kshs 25.64/kWh. The selected model had a higher levellized cost of energy than the pilot project because of higher interest and inflation rates. On the environmental aspect, 221,283.48 Kgs of carbon dioxide emissions would be saved in 20 years by using solar photovoltaic system. As per the LCOE of the optimal model over the grid, it would be replaced by Ksh 29.45/kWh instead of Ksh 33.8/kWh, yielding a percentage savings of 87%. The evaluation results especially the high- performance ratio (72.35%) showed that the technology adopted and site meteorological factors favored the high output of the solar photovoltaic system. The study recommends the utilization of information by stakeholders to develop a framework for performance improvement of the optimal model and pilot project in airports.