The objective of KEROGREEN is to produce CO2 neutral jet-grade fuel, the kerosene being synthesised from air and water, powered by renewable electricity. KEROGREEN meets UN ICAO CORSIA emission reduction targets and the EU Flightpath 2050 environmental objectives, as this fuel contains no sulphur, produces no soot and emits less NOx. At a generic level, coupling the renewable power sector to the fuel and chemical sector, Power-to-X, creates long-term, large-scale energy storage capacity needed to balance the grid and to strengthen EU energy security.
The KEROGREEN approach is uniquely based on plasma-driven dissociation of air-captured CO2, oxygen separation by high temperature oxygen conducting membranes and advanced Fischer-Tropsch (FT) synthesis to yield kerosene. Synergy between plasma-activated species and novel perovskite electrodes of the oxygen separator is shown to raise CO productivity, a valuable intermediate product. High heat transfer FT technology results in process intensification, producing long chain hydrocarbons at extended catalyst life time. Hydrocracking (HC) upgrades the FT wax to sustainable aviation fuel (SAF) compatible with current aircraft technology.
KEROGREEN has delivered an integrated container-sized system able to produce up to 0.1 l/hr kerosene. Such container is envisioned to be close coupled to a remotely sited renewable electricity plant, like an off-shore wind turbine. Surplus electricity is used to drive the chemical synthesis of liquid fuel which is transported inshore, stored and distributed to users by conventional pipeline or shipping means, with no need to stretch vulnerable and costly electricity cables across the sea.
Individual elements of the process chain are of dissimilar technology at widely varying Technology Readiness Level (TRL). The project objective is TRL4 - Technology validated in lab. To date, all elements have reached TRL3 - Experimental proof of concept. All but one have reached TRL 4 or beyond, including the CO2-splitting plasma reactor, the CO purifier, the sorption-enhanced water-gas-shift (SE-WGS) reactor, the FT synthesis reactor and the HC kerosene optimiser. Upscaling the lab-scale oxygen separator to system level has turned out to be a challenge and has been deferred to post-KEROGREEN activity, the mitigation scenario duly implemented.
