Photovoltaic/PEMFC hybrid energy system design and optimisation for residential applications in Afghanistan

Hybrid energy systems are systems that require the use of two or more energy sources together, especially in small-scaled renewable energy systems. In hybrid systems; Instead of using a single type of energy source with discrete nature such as solar energy, more than one energy source is used together to meet the load demand more effectively and economically. The solar radiation data, which is the main input of the hybrid system examined in this study, is a total annual radiation data measured on an hourly basis in Kabul, the capital of Afghanistan, design, and optimization is performed for the mentioned city. In this thesis, a hybrid energy system design and optimization of photovoltaic and proton exchange membrane fuel cell (PV/PEMFC) combining solar and hydrogen energies for housing applications in Afghanistan, is put into practice. The main purpose of the system is to meet the electricity requirement with PV/PEMFC hybrid system. In this study, by using two different load profiles, the performance of a hybrid system in different PV, PEMFC, and hydrogen storage capacity combinations for each load profile is determined. The performance of the system is calculated by the simulation program consisting of mathematical models of the system components in a MATLAB environment with the loss of load probability (LLP) parameter. The operating principle of the hybrid system is as follows: the first possibility; If the energy obtained from PV exceeds the load, the surplus energy is used to produce hydrogen by electrolysis of water. The hydrogen produced is stored in a tank in the form of the metal hydride. As a second possibility, if the energy produced from PV cannot meet the load, it is possible that the energy produced by using the stored hydrogen in the PEMFC can cover the charge. If the energy produced from PV cannot meet the load, and there is no stored hydrogen or the amount of hydrogen in the tank is too low to meet the load, so-called load loss occurs.