APOLO has worked on obtain high-efficiency flexible devices through the development of new materials and the implementation of novel photonic structures, guarantee the stability of new concepts through the application of tests based on the PV standards, low temperature manufacturing using sustainable materials and processes and finally the integration of the new flexible APOLO modules in BIPV demos. For high performance solar cells, APOLO consortium has defined a structure of advanced materials (ETL, HTL, new Perovskite formulation), processes (for passivation, scalable printing techniques, low temperature treatments) adding light trapping (LT) structures and dedicated encapsulation. Making a right combination an efficiency of 23,54% has been achieved in rigid substrate, and 20.7% in flexible PET/ITO that can be improved up to 24.02 adding LT supersubstrate although advanced modelling predicts up to 25.7%. All these works are the result coming for an intensive activity in modelling, advanced characterization, improved dedicated processes, looking for low cost and minimum environmental impact in the complete production processes. Recycling and refining of APOLO materials have been studied and recommendations are given. Among advanced characterization such as notably a method of potentiostatic photoluminescence imaging for microscopically resolved imaging of the charge extraction efficiency in PSC demonstrate to be a great tool. Protocols of performance characterization have been also developed and led to well-determined performance and lifetime measurements. Great efforts have been done in terms of encapsulation and finishing in order to increase lifetime and reduce operational and maintenance costs. In terms of encapsulant, APOLO activities have allowed to a patent development; meanwhile, antisoiling coating suitable for this encapsulant has demonstrated up to 19% of reduction of dust deposition. Going to PSC modules, all the knowhow onto cells has been translated, using developed models, including electrical and mechanical modelling. By using coupled optical and electrical models unprecedently have been explored by the partners APOLO were able to optimize and rigorously assess the transport properties of selected photonic-structured PSC architectures. The simulations have led to an optimized geometry of the integrated modules, particularly how to minimize the losses. Making like this, APOLO has achieved 17% PCE on modules and first ever PSC module on metal foil has been developed. Several improvements have been used in order to reduce the cost and the environmental impact such as test carbon-based materials has been investigated as a low cost and more sustainable alternative to evaporated costly metals as top electrodes. Solvent engineering has given a ternary solvent system for perovskite absorber layer deposition. LT also has been proven in upscaled solar cells, which allowed a sheet resistance reduction. APOLO has made three demos for BIPV. Their physical assembly revealed that the different components could be easily integrated in façade’s product. APOLO DEMO 3, composed of mini-modules, has demonstrated an excellent operational behaviour both under simulated sunlight and outdoor conditions. Further research beyond APOLO project should be directed to optimize large scale production of modules and to extend their lifetime by means of smart encapsulation designs and device layout configuration. The estimated cost to manufacture a flexible PSC module can be financially competitive with the existing flexible PV module in the market. LCA and LCC of the final solutions has been performed to quantify the environmental and socioeconomic performance. The results and final recommendation of APOLO can be used for fully achieve, consolidate and, if possible, surpass the performance objectives and to maximise use phase benefits, while striving for a simultaneous reduction of key manufacturing impacts and investment cost.
