Integration of solar heating systems for low-temperature heat demand in food processing industry – a review

Abstract

The future of climate-resilient energy systems relies on the transition to incorporate renewable energy with energy storage, such as solar energy. Solar thermal provides desirable thermal energy (heat) for industry, commercial, and residential sectors. Significant attempts have been made to improve the design and its integrated systems, thus reducing the costs and making the technology more competitive for industrial applications. This paper evaluates the solar thermal potential and the economic feasibility standard of the technology from low-temperature heat demand up to 100 °C by focusing on the food industry. Throughout this review, theoretical concepts, design types, and recent developments related to this sector's integration systems are explored. This study also highlights the integrated systems gap and emphasises the assessment of integration points and the range of operating temperature. This review aims to assist industries in the food processing sector to keep them abreast with the latest solar technology developments for the food industry. Up to 2020, at least 95 solar thermal plants with a total capacity of 41 MWth had been installed globally for the food industry. The flat plate collectors were the most applied solar collectors in the food industry, represented by 38%. It has been shown that the most common heat applications are pre-heating, cleaning and pasteurisation. The configuration and design of the integration framework for this sector rely primarily on each application's specific features and nature of the process. Based on the installed solar thermal plant, 27% was used for heating of make-up water.