Energy plays an important role in our lives. It comes in several forms which can be utilised to keep people warm during cold weather, provide foods, improve transportation, and increase productivity. When energy is utilised efficiently, it brings great comfort to our lives. However, energy consumption has been increasing in recent decades as the world population keeps growing. According to a United Nation (UN) report, the current world population of 7.4 billion is projected to increase by 1 billion over the next 10 years and reach 9.6 billion by 2050. Besides population, the standards of living for many people in developing countries is increasing, which in turn results in growing energy demand.