Increasing the share of renewables in the European energy mix has a key function for the security of energy supply and the reduction of greenhouse gas emissions from fossil fuels. This proposal is entitled “Framework of Innovation for Engineering of New Durable Solar Surfaces”, (acronym FRIENDS2) and aims at achieving a European network for the transfer of knowledge to establish a shared culture of research and innovation which allows turning creative ideas in the field of surface engineering into innovative solutions for concentrating solar power (CSP) applications. FRIENDS2 will be led by one large European industry (Abengoa) who is a world leader in the development of CSP plants. The other FRIENDS2 participants are two well-recognized academic organizations (the University of Cranfield and the Helmholtz-Zentrum Dresden - Rossendorf e.V.), and one SME (Metal Estalki). The purpose of FRIENDS2 is to strengthen the inter-sectoral capabilities in research and development of coating designs in order to improve the performance of CSP key components (reflectors, receivers and containers for heat storage) for high temperature applications. The methodology of this joint research proposal contains aspects of very high novelty. It includes computer modelling, multi-technique coating deposition, use of advanced characterization techniques, and the possibility of scaling-up new coating developments. Special attention is paid to the intersectoral transfer of knowledge and to the establishment of a long-lasting international network with global impact. It is worth noting that a substantial fraction of secondments (51%) will be carried out from the industrial to the academic sector. With the proposed approach, there will be an effective transfer of knowledge among the partners which will pave the road from fundamental research to applied innovation of surface engineering solutions for further CSP development.

Liquid hydrocarbon fuels are ideal energy carriers for the transportation sector due to their exceptionally high energy density and most convenient handling, without requiring changes in the existing global infrastructure. Currently, virtually all renewable hydrocarbon fuels originate from biomass. Their feasibility to meet the global fuel demand and their environmental impact are controversial. In contrast, SUN-to-LIQUID has the potential to cover future fuel consumption as it establishes a radically different non-biomass non-fossil path to synthesize renewable liquid hydrocarbon fuels from abundant feedstocks of H2O, CO2 and solar energy. Concentrated solar radiation drives a thermochemical redox cycle, which inherently operates at high temperatures and utilizes the full solar spectrum. Thereby, it provides a thermodynamically favourable path to solar fuel production with high energy conversion efficiency and, consequently, economic competitiveness. Recently, the first-ever production of solar jet fuel has been experimentally demonstrated at laboratory scale using a solar reactor containing a ceria-based reticulated porous structure undergoing the redox cyclic process. SUN-to-LIQUID aims at advancing this solar fuel technology from the laboratory to the next field phase: expected key innovations include an advanced high-flux ultra-modular solar heliostat field, a 50 kW solar reactor, and optimized redox materials to produce synthesis gas that is subsequently processed to liquid hydrocarbon fuels. The complete integrated fuel production chain will be experimentally validated at a pre-commercial scale and with record high energy conversion efficiency. The ambition of SUN-to-LIQUID is to advance solar fuels well beyond the state of the art and to guide the further scale-up towards a reliable basis for competitive industrial exploitation. Large-scale solar fuel production is expected to have a major impact on a sustainable future transportation sector.