SolDAC is a 36-month project funded by the European Commission and the Innovate UK, gathering 8 partners from 4 different countries, which aims to reinvent the ethylene industry, which is the chemical industry’s primary building block, by proving an emerging breakthrough technology for producing technically and economically competitive and climate-neutral sustainable ethylene and co-product ethanol from solar energy and air.

SolDAC process counts with three main units: Photo-Electrochemical Conversion unit (PEC), Full Spectrum Solar collector (FSS) and Direct Air Capture unit (DAC).

The Photo-Electrochemical Conversion unit (PEC) allows the direct conversion of carbon dioxide into ethylene. This unit exploits bandwidth-selected light from a solar collector (FSS) that splits the solar spectrum 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 more than 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 by-product ethanol. The process offered by SolDAC is energetically self-sufficient, economically viable and carbon-negative on the condition that each unit (DAC, PEC, FSS) reaches new targets in efficiency.