SOLAR THERMAL APPLICATIONS UNIT

Solving water issues for CSP plants (SOLWARIS)

Participants: TSK (Coordinator), CEA, DLR, CIEMAT, Cranfield University, Fundación Tekniker, Rioglass Solar, Ingeniería para el Desarrollo Tecnológico, FENIKS, Barcelona Supercomputing Center, BrightSource Industries (Israel) Ltd, AMIRES.

Contacts: Patricia Palenzuela, patricia.palenzuela@psa.es
Aránzazu Fernández García, arantxa.fernandez@psa.es
Eduardo Zarza Moya, eduardo.zarza@psa.es

Funding agency: European Commission, EU-H2020-LCE-11-2017.

Background: Water consumption is a major issue for the commercial deployment of CSP/STE plants in desertic areas. Several technical innovations for water saving have been identified and some of them are already under development in the H2020 WASCOP project. SOLWARIS is somehow the continuation of the work initiated in WASCOP.

Objectives: The main objective of SOLWARIS is the testing and validation in a real commercial environment of important innovations for water saving in CSP/STE plants. These innovations include: anti-soiling coatings for mirrors and receiver tubes, advanced cleaning systems, water recovery systems for the BOP and cooling tower effluents, cooling thermal energy storage and a plant O&M optimizer including soiling rate forecast.

Achievements in 2021: In WP3, CIEMAT has completed a study of a hydrophobic anti-soiling coating on the glass tubes of RIOGLASS receivers (subtask 3.4.3). In addition, CIEMAT has studied the effect of the coating on the optical properties, the abrasion resistance and the durability under condensation conditions in CIEMAT laboratory by testing samples of commercial tubes.

The results showed that the coating was stable under the conditions tested and variations in abrasion behaviour were observed by the anti-soiling treatment. CIEMAT has also concluded the assessment of the durability of the anti-soiling coating for reflectors developed by IK4-TEKNIKER and RIOGLASS (subtask 3.4.2), by testing coated samples under accelerated aging conditions.

In WP5, work has focused on the development of the dynamic model of the multi-effect evaporation plant for water recovery purposes in a CSP plant, which has been implemented in Dymola software. All components of the plant have been modelled (bundle tube of each effect, steam ejector, desuperheater, cyclonic box of each effect, final condenser, plate heat exchangers, mixed tank). Likewise, the model has been validated with data given by the manufacturer (INDETEC), obtaining a good agreement between the results of the model and the design data. Finally, a sensitivity analysis was carried out, in which the dynamic response of the system against disturbances was in the main operating variables. This has been reflected in a paper that was sent to the SCI journal Desalination at the end of 2021.