Hybrid power systems – Sizes, efficiencies, and economics

In the context of electricity generation in the oil and gas producing countries, it has become implicit to develop new, clean, and renewable sources of energy to supplement the fossil fuel based power generation. With this single aim, one can hit two targets, conservation of fixed fossil fuel resources and combat the adverse climatic changes to safeguard our planet. In regional context, solar photovoltaic, solar thermal, wind power, geothermal, and hydro power are alternative sources for power mitigation. Of these renewables, wind, solar photovoltaic (PV), diesel, and energy storage in hybrid combinations are the possible ways to supply continuous energy for all sizes of applications. This paper provides a review of the existing hybrid power systems and the theoretical studies around the globe in varied climatological conditions to identify the best combinations of hybrid systems for Saudi Arabia to supplement the existing energy portfolio. The wind/solar-pv, wind/solar-pv/diesel, and solar-pv/diesel with and without battery backup are most commonly used systems with respective popularity of 28, 22, and 21%. Among users, remote communities are the highest while islands and communication towers are the next common applications. Average costs of energy of wind/solar-pv, wind/solar-pv/diesel, and solar-pv/diesel are around 0.458, 0.355, and 0.349 US$/kWh.