Soluciones termosolares para integración en procesos industriales (SOLTERMIN)

Participants: CIEMAT-PSA
Funding: Spanish Ministriy of Economy, Industry and Competitiveness (Programa RETOS. Convocatoria 2017)
Reference: ENE2017-83973-R
Duration: January 2018 – June 2022


Concentrating thermal solar energy’s development and commercial implantation have experienced a dramatic growth in the last few years. Currently there are more than 5 GWe installed worldwide in order to generate electricity.
However, this commercial display has not increased the thermal solar energy’s contribution to the industry, which is a huge potential market. According to a report published in 2015 by the International Energy Agency (IEA) and the International Renewable Energies Agency (IRENA), 2030 will have the technical potential to provide with around 4.17 million GWh of energy with thermal solar systems.
World widely, more than a 66% of the total energy consumption in industry is used in heating processes, and a 50% of this energy consumption is carried out under 400ºC. There are some application areas such as food, textile, machinery and paper where the needed temperatures are under 250ºC and, therefore, it seems interesting to consider using linear concentrating solar technologies adapted to each ones energetic/economic needs and with a suitable performance/cost relationship. There are also other interesting industrial sectors, such as metallurgy and ceramic industries, which require temperatures higher than 400ºC, where high concentrating solar systems can also be used.    
These needs have motivated this research project that includes activities related with the optimised development of concentrating solar compact systems and the solar receiver’s development, and the integration of complete systems in individual industrial processes, which constitute case studies we have taken into consideration.
This project’s main goals have been to contribute to the development of compact and optimised solutions for concentrating thermal solar energy technologies’ that may be suitable for heating supply in industrial processes.
The project’s specific goals have been the following:

  • Design and development of a Fresnel linear compact collector prototype suitable for being used when applying small and medium power process heat.
  • Studying the integration of Fresnel linear compact collectors in industry: a) in food/drink industrial heat processes and, b) in a multi-effect distillation with thermal vapour compression
  • Developing an innovative heliostat solutions for central receiver systems in a multi-tower concept and studying the design of volumetric receiver innovations.
  • tudying a mini-tower system integrated in a cogeneration plant by coupling a Brayton cycle and taking advantage of the waste heat to feed a multi-effect distillation plant. 

Outstanding results of the project
As a summary of the results obtained, the following figure shows photographs of the prototypes of the linear Fresnel collector (CFL) and self-aligned optics heliostat (point Fresnel collector, CFP).

View of linear Fresnel collector patented and built in the project, for supplying thermal energy at medium temperature.
View of self-aligned-optical heliostat under development in the project, for integration into central tower systems.

In addition, the following list summarizes the most relevant publications with results of the project:

  1. García-Segura A, Fernández-García A, Buendía-Martínez F, Ariza MJ, Sutter F, Valenzuela L. Durability studies of solar reflectors used in concentrating solar thermal applications under corrosive sulfurous atmospheres. Sustainability 2018; 10(9):3008; DOI:
  2. Pulido-Iparraguirre D, Valenzuela L, Serrano-Aguilera JJ, Fernández-García A. Optimized design of a Linear Fresnel reflector for solar process heat applications. Renewable Energy 2019; 131:1089-1106.
  3. Carballo JA, Bonilla J, Roca L, Berenguel M. New low-cost solar tracking system based on open source hardware for educational purposes. Solar Energy 2018; 174:826-836; DOI:
  4. Pulido-Iparraguirre D, Valenzuela L, Fernández-Reche J, Galindo J, Rodríguez J. Design, manufacturing and characterization of Linear Fresnel reflectors’s facets. Energies 2019; 12(14):2795.
  5. García-Segura A, Fernández-García A, Ariza MJ, Sutter F, Diamantino TC, Martínez-Arcos L, Reche-Navarro TJ, Valenzuela L. Influence of gaseous pollutants and their synergistic effects on the aging of reflector materials for concentrating solar thermal technologies. Solar Energy Materials and Solar Cells 2019; 200:109955.
  6. Avila-Marin AL, Fernández-Reche J, Martínez-Tarifa A. Modelling strategies for porous structures as solar receivers in central receiver systems: A review. Renewable and Sustainable Energy Reviews 2019; 111:15-33. DOI:
  7. Carballo JA, Bonilla J, Berenguel M, Fernández-Reche J, García G. Solar tower mockup for the assessment of advanced control techniques. Renewable Energy 2020; 149:682-690; DOI:
  8. Carballo JA, Bonilla J, Roca L, de la Calle A, Palenzuela P, Alarcón-Padilla DC, M Berenguel. Optimal operation of solar thermal desalination systems coupled to double-effect absorption heat pumps. Energy Conversion and Management 2020; 210:112705. DOI:
  9. Palenzuela P, Ortega-Delgado B, Alarcón-Padilla DC. Comparative assessment of the annual electricity and water production by concentrating solar power and desalination plants: A case study. Applied Thermal Engineering 2020; 177:115485. DOI:
  10. Mata-Torres C, Palenzuela P, Zurita A, Cardemil JM, Alarcón-Padilla DC, Escobar RA.  Annual thermoeconomic analysis of a Concentrating Solar Power + Photovoltaic + Multi-Effect Distillation plant in northern Chile. Energy Conversion and Management 2020; 213:112852. DOI:
  11. Buendía-Martínez F, Sutter F, Wette J, Valenzuela L, Fernández-García A. Lifetime prediction model of reflector materials for concentrating solar thermal energies in corrosive environments. Solar Energy Materials and Solar Cells 2021; 224:110996. DOI:
  12. García-Segura A, Sutter F, Martínez-Arcos L, Reche-Navarro TJ, Wiesinger F, Wette J, Buendía-Martínez F, Fernández-García A. Degradation types of reflector materials used in concentrating solar thermal systems. Renewable and Sustainable Energy Reviews 2021; 143:110879. DOI:
  13. Mata-Torres C, Palenzuela P, Alarcón-Padilla DC, Zuriza A, Cardemil JM, Escobar RA. Multi-objective optimization of a Concentrating Solar Power + Photovoltaic + Multi-Effect Distillation plant: Understanding the impact of solar irradiation and the plant location. Energy Conversion and Management: X 2021; 11:100088. DOI:
  14. Farchado M, San Vicente G, Germán N, Maffiotte C, Morales A. A Highly Stable and Sustainable Low-Temperature Selective Absorber: Structural and Ageing Characterisation. Materials 2022; 15 (10):3427. DOI:
  15. Avila-Marin A.  CFD parametric analysis of wire meshes open volumetric receivers with axial-varied porosity and comparison with small-scale solar receiver tests. Renewable Energy 2022; 193:1094-1105. DOI:
  16. Fernández-Reche J, Valenzuela L, Pulido-Iparraguirre D. Measuring Concentrated Solar Radiation Flux in a Linear Fresnel-Type Solar Collector. Solar 2022; 2(4):401-413. DOI: