Background Photovoltaic renewable energy technologies have gained a reputation for being sustainable and environmental compatible. Thin film photovoltaic panels (TFPV) are becoming increasingly popular but need to be carefully recycled at the end of their life cycle since hazardous substances used in the panels may harm the environment if they are not disposed of properly. Furthermore, conventional recycling processes for TFPVs use toxic substances with limited availability and these factors combine to reduce net environmental benefits from recycling TFPPs. Objectives The main purpose of this RESOLVED (Recovery of Solar Valuable Materials, Enrichment and Decontamination) project was to identify new techniques that helped increase the net environmental benefits from recycling TFPVs. The aim was to create a process that offered cost effective recovery of raw material from semi-conductors and also decontaminated the remaining materials. This involved exploring alternative methods for wet-mechanical treatments in the recycling process in order to reduce consumption of toxic chemical compounds, like Cadmium-Telluride (CdTe). A range of analytical methods were applied including assessing: life-cycles; process sustainability; economic aspects; resource availability; and socio-economic impacts. Results RESOLVED achieved its objectives and successfully developed new recycling methodologies for TFPVs, featuring module crushing, wet mechanical separation and enrichment, to produce separated CdTe semiconductor material with a purity of 99,99%. A number of inter-related results were achieved to facilitate this outcome. These included: developing a twin-strategy for the TFPV recycling, involving two coalescing recycling loops; demonstrating the feasibility of wet mechanical processing for end-of-life modules, using both attrition and flotation methods as well as application of the combined thermal, dry mechanical (vacuum blasting) and wet mechanical methods; and verifying a new enclosed and environment-friendly online analysis for treatment of high output flows of non-homogeneous materials. The feasibility of all process steps was demonstrated in the semi-technical scale as well as in the laboratory scale and the quality of the purified metals (Cd and Te) is sufficient for the production of new CdTe modules. Conclusions from Life-Cycle-Analysis proved that the innovative recycling strategy has clear environmental advantages when compared against land-fill or incineration options, as well as in comparison with the thermal treatment which involves high fuel consumption during the heating process. RESOLVED’s net environmental benefits demonstrate that the new recycling technology can make useful contributions to the prevention of photovoltaic waste streams and preservation of scarce natural resources. As such, the LIFE project’s environmentally friendly technology complements the WEEE and RoHS EU Directives. The beneficiary anticipates that their RESOLVED approach will become increasingly popular and cost effective in the near future as a commercial treatment process for recovering valuable solar panel materials. Some fine tuning is still on-going to optimise the washing process after attrition and enhance the selectivity of flotation within the recycling procedures. These issues are not considered major concerns and cooperation is now being sought with appropriate companies to launch a commercial version of the technology that will be economically competitive and capable of converting growing TFPV waste volumes into worthwhile raw materials for reuse. RESOLVED staff also notes that the process will help strengthen the reputation of thin film technologies and so improve their acceptance by the public and authorities. Further information on the project can be found in the project's layman report (see "Read more" section).