A hybrid dry/wet cooling system was developed, where deluge cooling technology was integrated into existing air-cooled condensing technology. Detailed engineering design was carried out for the new cooling system complete with a 3D CAD model to support constructability studies and more detailed capital cost calculations. Performance modelling equations for thermal performance, auxiliary power consumption and water consumption were derived.
A new axial flow fan for a CSP plant was developed and designed based on duty point specific aerodynamic optimization. Noise level reduction techniques were investigated as part of the development process. A scale mode magnetic gearbox was developed and tested, aimed as a potential replacement of state-of-the-art gears in the fan drive train.
A further work package covered the development of compact heat exchanger technology based on wire structure heat transfer surfaces for potential use in large-scale cooling systems. Design and optimization was carried out with the support of CFD analysis. Sample heat exchangers making use of wire structures were subsequently manufactured and tested for heat transfer and air-side pressure drop.
Truck-based spray- and brush-type mirror cleaning systems were developed for parabolic and heliostat collector fields, where the focus of the improved technology was on cleaning water consumption reduction. A cleaning robot was designed for Fresnel collector applications. New cleaning strategies based on collector reflectance spatial monitoring and cleanliness threshold values were developed.
Water management and water treatment were further focus areas. A concept for designing a water management plan for a CSP plant based on steady-state mass balances was created and a new MinWaterCSP approach towards water use and management was defined. The overall water mass flows were reduced through the new technologies and as a result the capacity of water treatment units and annual treatment costs were reduced.
Scaling and fouling as found during deluge cooling was investigated. A test rig simulating actual heat transfer and operating conditions was constructed and operated at Green Energy Park in Benguerir, Morocco.
A full-scale axial flow fan of 30ft diameter was designed, constructed and tested at Matimba Power Station, South Africa. This work package also included the construction of a full-scale 24ft diameter axial flow fan and deluge cooling water functional test facility at the University of Stellenbosch, South Africa, as part of the hybrid cooling system development initiative.
CSP plant simulation software ColsimCSP was further developed to include all water and wastewater streams found throughout a CSP plant. Various CSP plant simulations dealing with state-of-the-art CSP reference plants and new CSP plant designs incorporating the MinWaterCSP developments were carried out as part of benchmarking and optimization studies.
Two work packages dealt with communication, dissemination and exploitation. Two conference events were arranged in Marrakech, Morocco, and Stellenbosch, South Africa, where project results were presented and an international audience was reached. A large number of stakeholders were reached through the MinWaterCSP website, press releases, newsletters, blogs, social media and site visits. Several exploitation workshops were held and exploitable results were identified. Business plans were generated for selected exploitable results.
