Optimal Sizing of Renewable Hybrid Energy System: A Review of Methodologies

The ever-growing energy demand, the intermittent nature of renewable energy resources such as wind, photovoltaic etc coupled with issues of reliability makes the hybrid renewable energy systems more preferred. Hybrid energy sources offers better reliability and cost effectiveness than a single energy source. One of the most important issues related to hybrid renewable energy systems is obtaining the optimal size of their parts so as to utilize them efficiently and economically. Determining the optimal size of hybrid energy systems helps to avoid over-sizing or under-sizing of the system which will subsequently affect the cost and reliability of the system. Optimal sizing becomes complex when considering multiple hybrid mix while at the same time considering various objectives such as cost, CO2 gas emission and reliability. This paper aims at critically reviewing the various optimization techniques used in optimal sizing of various combination of hybrid energy sources for effective selection of the appropriate sizing method for hybrid renewable energy systems. It has been found that meta-heuristic techniques are well suited for optimal sizing of the hybrid energy systems with Genetic Algorithm and Particle Swarm Optimization techniques being the most commonly used Algorithms.