Solar thermal energy technologies and its applications for process heating and power generation – A review

The industrial sector accounts for more than 54% of the total energy produced in the world with a predicted annual growth of 1.2%. Currently, most of the industrial sectors use fossil fuels to meet their heat energy requirements and it can be replaced by renewable energy resources particularly solar energy. In this article, an extensive review of various solar thermal energy technologies and their industrial applications are presented. The following industries are covered: power generation, oil and gas, pulp & paper, textile, food processing & beverage, pharmaceutical, leather, automotive, and metal industries. For each of the applications, quality and quantity of heat requirements are identified. Though all the applications are consuming heat in the form of steam/hot water, power plant and enhanced oil recovery have huge potential for solar steam augmentation as compared to other applications. Similarly, applications such as petroleum refining, pulp & paper, and rice mill require a huge amount of steam/hot water. The process heat requirements for textile, food & beverage, pharmaceutical, leather, and automotive industries are at a lower temperature. The integration of solar thermal energy systems with the industrial processes mainly depends on the local solar radiation, availability of land, conventional fuel prices, quality of steam required, and flexibility of system integration with the existing process. Furthermore, challenges involved in the integration of solar thermal energy systems with the process heat industries are explored along with the economics. The future outlook has been proposed to overcome the challenges involved in the integration.