Study 23: The potential of solar thermal energy in industry

This study, which focuses on the potential for integrating solar thermal energy into industrial processes, aims to provide an initial overview of the technical and economic feasibility of these solutions.

Globally, heat consumption in industry accounts for nearly 24 per cent of final energy consumption, across all uses and all energy sources. This corresponds to nearly 24,000 TWh. By distinguishing between different temperature levels, it is possible to identify solar thermal technologies that could meet part of this energy demand.

The study consists of four parts: 

• The first part is devoted to a review of the state of the art in solar thermal technologies (collectors, storage and operating principles) that can be used to supply heat for industrial processes: fixed or tracking flat-plate collectors, vacuum tube collectors, vacuum flat-plate collectors and concentrating collectors are briefly described, with information on their ability to supply heat at varying temperatures. Thermal storage technologies, which are rarely separate from solar collectors, are also discussed.
• The second part discusses the methodology required to integrate solar heat.
• Part Three is devoted to economic aspects.
• Finally, four detailed case studies provide an insight into solar thermal installations integrated into industrial processes. They illustrate the variety of solutions that can be implemented to meet different objectives.

In summary, this study highlighted four conclusions: 

• The need to carry out detailed energy analyses to facilitate the integration of solar thermal systems, and to use the most suitable technology,
• The variety of solutions available to meet a large proportion of industry’s low- and medium-temperature (up to 400°C) heating requirements, as well as their level of maturity,
• The cost-competitiveness of solar heating compared with conventional solutions and, above all, its resilience to changes in the energy market, given its very low running costs,
• An environmental impact 10 to 20 times lower than that of fossil-based natural gas.