Counteracting the progressing global climate change requires drastic reductions in greenhouse gas emissions of 40 – 70 % throughout all sectors until 2050 (compared to emissions from 2010) [IPCC 2014]. In response to that the aviation industry aims at reducing its carbon emissions by 50 % until 2050 compared to emissions in 2005 [IATA 2017]. The implementation of propulsion systems not based on liquid hydrocarbons appears challenging due to the high weight of current battery packs and the complicated implementation of hydrogen-powered aircraft. Sustainable alternative fuels, however, have a high energy density and can be directly utilized in current aircraft engines and fuel distribution systems, which allows for quick and efficient emission reductions in the aviation sector. One promising option to produce these fuels is the so-called Power to Liquid (PtL) pathway, which produces jet fuel using only electricity, water and CO2 as input. As opposed to other sustainable jet fuel pathways PtL systems show a high technological readiness, require no agricultural land, are compatible to all electricity sources and have a good perspective for future low-costs production due to dropping costs for components and renewable electricity. In order to assess the current potential of PtL fuels to substitute a large share of today’s jet fuel consumption, a comprehensive geographic information system (GIS)-based analysis of expectable production volumes and costs in the USA is performed in this work. The plant’s electricity demand is met solely from photovoltaic or wind energy, in order to maintain a beneficial greenhouse gas (GHG) emission balance over the fuel’s whole lifecycle. All regions in the USA are preliminarily assessed, whether a renewable energy production is suggested in terms of topography and competing land use. The subsequent performance assessment of the PtL plant is based on a model of a proton exchange membrane electrolyser producing hydrogen, followed by a Reverse-Watergas-Shift reactor that converts H2 and CO2 to CO and H2O. The mixture of H2 and CO (syngas) is subsequently sent to a Fischer-Tropsch reactor for hydrocarbon synthesis. The final process step is the upgrading of syncrude to jet fuel and other by-products. CO2 demands of the plant are either satisfied by direct air capture (DAC) or by renewable CO2 point sources due to sustainability restrictions. The expected electricity production from solar or wind power, as well as its temporal distribution, is estimated in each raster cell and the respective PtL plant size, as well as storage sizes for hydrogen and electricity, are adjusted to this electricity output. Results show that on the available areas in the USA more than seven times the current global jet fuel demand could be produced by DAC-based PtL systems. Plants powered by one-axis tracked PV are the dominant technology due to their low electricity costs and high production rates per area. The costs to produce the 2018 U.S. jet fuel demand by these systems are expected to be between 3.35 and 3.39 $/l with an average of 3.38 $/l, while claiming ca. 0.28 % of the U.S. area for the production. The additional electricity demand equals 72 % of the U.S. electricity generation capacity. Significant cost reductions are possible when utilizing renewable CO2 point sources, whereby limitations of the renewable CO2 supply allow currently only for a jet fuel production equal to 19.4 % of the U.S. demand.     «

Counteracting the progressing global climate change requires drastic reductions in greenhouse gas emissions of 40 – 70 % throughout all sectors until 2050 (compared to emissions from 2010) [IPCC 2014]. In response to that the aviation industry aims at reducing its carbon emissions by 50 % until 2050 compared to emissions in 2005 [IATA 2017]. The implementation of propulsion systems not based on liquid hydrocarbons appears challenging due to the high weight of current battery packs and the compli...     »