Ethylene is the chemical industry’s primary building block. SolDAC’s ambition is to reinvent the ethylene industry by proving (TRL4) an emerging breakthrough technology for producing technically and economically competitive, socially desirable and climate-neutral (sustainable) ethylene and co-product ethanol (C2 products) from solar energy and air. The project features a photo-electrochemical conversion (PEC) unit, being electrochemistry the only possible route for direct conversion of carbon dioxide into ethylene. The PEC exploits bandwidth-selected light from a solar collector (FSS) thatsplitsthe solarspectrum for electricity and heat generation at efficiency higher than standalone PV modules and standalone solar thermal collectors. Heat is used in an innovative direct air capture (DAC) unit at ultralow temperature (~60°C), fostering the eventual circular integration with heat networks. The DAC unit removes carbon dioxide from the air, concentrates it to 95+% and compresses it to feed the PEC stack and a pipeline for carbon dioxide storage. This allows the carbon footprint of the whole sun-to-chemicals process to be offset and enables gain in carbon credits, opening an opportunity to exceed climate-neutrality and produce carbon-negative C2 products. The process is energetically self-sufficient, economically viable and carbon-negative on the condition that each unit (DAC, PEC, FSS) reach new targets in efficiency. That is exactly the high-risk/high return outcome expected in the project. The research is balanced to overcome technical, early-stage social and market barriers by exploiting the expertise of its 8 partners (SMEs in the renewable technology field, leading EU research institutions and one networking NGO). This project performs all the necessary groundwork for the full deployment of the process before 2050 through activities that build up a new ecosystem of stakeholders, making Europe the first circular, climate-neutral and sustainable economy