Cost, reliability, and sensitivity of a stand-alone hybrid renewable energy system-A case study on a lecture building with low load factor

Single source renewable energy systems exhibit strong short term and seasonal variations in their outputs for which hybrid systems are the need of the hour. Taking consideration of the location, user requirements, cost, reliability, etc., the hybrid systems are designed. The objective of the present study is to evaluate cost and reliability of a standalone hybrid renewable energy system (HRES) to be utilized for a lecture building of a technical institute with low load factor. Different combinations of HRES involving horizontal axis wind turbine, solar photo voltaic (PV), proton exchange membrane fuel cell with electrolyzer, and battery bank have been studied. Four such systems have been modeled using hybrid optimization model for electric renewable HOMER software, and these are techno-economically evaluated for the existing low load factor conditions of the building. Futuristic growth of load demand is also incorporated to analyze the results. It has been found that the combination of wind turbines, solar PV system, and battery bank gives the most cost effective hybrid system for both the load scenarios. And PV, fuel cell, wind turbine, and battery bank type HRES have the better reliability in terms of lower unmet load. (C) 2015 AIP Publishing LLC.