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1. Annual Conference of the SWEET consortium reFuel.ch

Experts from research and industry discussed the technical and regulatory challenges of implementing sustainable fuels and platform chemicals at the first annual conference of the SWEET consortium reFuel.ch.
September 23, 2024
“Project portfolio and degree of implementation make the fulfillment of the EU SAF quota likely, the PtL quota unlikely.” stated Bernhard Dietrich, at the 1. Annual Conference of the SWEET consortium reFuel.ch
“Project portfolio and degree of implementation make the fulfillment of the EU SAF quota likely, the PtL quota unlikely.” stated Bernhard Dietrich, at the 1. Annual Conference of the SWEET consortium reFuel.ch

Approximately 100 participants, with around half representing the private sector and federal offices, gathered at the V-Zug premises to discuss the initial results of the young consortium and to receive input from external experts.

Bernhard Dietrich gave an impressive presentation on "Forecasts for Renewable Aviation Fuel and Its Consequences." He explained that numerous Power-to-X (PtX) projects are currently under development. However, after the feasibility studies, many of these projects face a significant risk of termination. Experience has shown that the primary reasons for this include unclear regulatory and legal situations, new and complex technologies, and uncertain demand. As a result, (used) vegetable oil is currently and for the medium term the preferred raw material for aviation fuel. However, all parties agreed that the quantities available in the long term will not be sufficient.

For the researchers in the consortium, this underlines the need to solve the open social and technical issues for the time when vegetable oil-based fuels are no longer sufficient to ensure the necessary reduction in greenhouse gases.

Frederic Vogel introduced a different way to produce jet fuel via biomass, such as green waste, manure, or wood residues. He summarized the state of the art and the challenges associated with sourcing bio-oil from these biomass substrates through hydrothermal liquefaction. This bio-crude serves as a precursor for various types of fuels.

These topics were also the focus of panel discussions and the poster session that took place on this day.

Besides aviation, high-temperature processes in industry are also facing significant decarbonization challenges. During the lunch break, V-Zug, the event's host, invited the participants to a guided tour of the enameling oven. Christian Bach explained that V-Zug is pursuing plans to use hydrogen for heat-intensive processes and to extract it from methane through pyrolysis. This process removes the resulting carbon from the atmospheric carbon cycle as pellets.

In summary, it was an informative day that offered insights via specialist presentations and plenty of opportunities for informal discussions.

Selected presentations from the day can be downloaded here: Link

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Latest findings from research

Research Paper on global cost drivers for low-carbon fuels in Energy & Environmental Science
Papers

Global cost drivers and regional trade-offs for low-carbon fuels: a prospective techno-economic assessment

Low-carbon fuels (LCFs) such as green hydrogen, synthetic hydrocarbons, and biofuels are critical for decarbonizing sectors that are difficult to electrify. In this study, we present a globally harmonized techno-economic assessment of 21 LCF production pathways, including power-to-X, biomass- and sun-to-liquids, and multiple hydrogen routes, evaluated across all countries under three future scenarios for 2024, 2030, and 2050. The model integrates spatially explicit resource data, learning-driven capital cost trajectories, and dynamic, country- and technology-specific costs of capital, supported by robust scenarios and uncertainty analysis. By 2050, median levelized costs are projected to range from 0.07 to 0.10 EUR2024 per kWh for green hydrogen, 0.15 to 0.18 EUR2024 per kWh for power-to-liquid kerosene, and 0.14 to 0.20 EUR2024 per kWh for most bio-based aviation fuels, reflecting both substantial progress and persistent regional disparities. Our results show that while innovation, technology learning, and deep power sector decarbonization can unlock cost-competitive electrofuels in countries with abundant renewables, bio-based routes are frequently cost competitive for sustainable aviation fuel (SAF) production in near-term scenarios, and solar-to-liquid fuels remain constrained by feedstock availability and capital barriers. Nuclear- and methane-based hydrogen emerge as primary options in many regions, as well as the dominance of turquoise hydrogen in Russia, the Middle East, and Central Asia where carbon management is viable, which highlights the context-specific nature of future LCF systems. We also found that the least-cost logistics for global hydrogen trade will shift from ammonia shipping to pipeline transport and methanol delivery, with North Africa and Iberia emerging as leading suppliers to Europe. These findings underscore the need for integrated innovation, policy coordination, and investment strategies that address both resource and financial barriers, in order to achieve scalable, resilient, and cost-effective LCF supply chains worldwide.
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Active Phase–Support Interaction in Phosphotungstic Acid-SiO2 Catalysts Enables Enhanced Olefin Oligomerization to Synthetic Fuel

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