At the start of the project, we first assessed drivers of trade in renewable fuels and how they may reconfigure the global energy regime, providing the basis for all later analysis. Subsequently, we analyzed climate data used in energy system models and found that state-of-the-art global climate data sets are able to simulate solar PV and wind power generation well, but that nevertheless deviations may be significant for single regions and a validation is therefore recommended. Our work on long-time climate data also allowed us to show that power systems without stringent regulation for security of supply may be exposed to power deficits caused by climate extreme events, and that wind power is beneficial to power systems in Central Europe due to its temporal generation profile.
On the land-use impacts side, we found in a large-scale literature review that existing assessments of the land-use requirements of renewable energy facilities on land show high uncertainties globally. In a more detailed analysis for Brazil, we concluded that wind power generation has expanded predominantly on ecologically sensitive land. We also found that wind power and solar PV projects in Brazil are in many instances linked to large-scale investments from European companies (see Figure), and that those projects are associated with privatizations of public land, therefore potentially fuelling conflicts with traditional populations. These impacts have also been studied in qualitative online workshops with local communities and Brazilian partner organizations, and in empirical fieldwork, where we found that renewable energy projects have a variety of detrimental effects on communities. These findings have been disseminated to the general public in Brazil, during a public audience and on a website. In a methodologically and geographically contrasting regional case study in Europe, we showed that the local social cost of wind power generation implied by administrative choices of wind power zones is high.
We have also shown how synthetic fuel production in Brazil can be integrated with existing biofuel production to increase land-use efficiency of both processes. Without expanding current land-use, integrating synthetic fuels into bio-ethanol facilities will allow reaching Brazilian biofuel production goals until 2030. However, no substantial surplus for exports can be expected. As a final contribution of the project, we assessed current EU policy, which aims at importing a significant amount of hydrogen from outside of the EU until 2030. This can lead to additional emissions, as renewable electricity used for hydrogen exports could otherwise be used for decarbonization of the power systems in the exporting countries.
We conclude that the development of inter-regional or inter-continental trade streams for synthetic fuels faces important challenges: first, economic competitiveness is low, unless production schemes can rely on large, cheap and clean streams of CO2 in the production process and costs for electrolyzers decrease substantially. Furthermore, synthetic fuels have larger land related impacts than using direct electrification. We found that these impacts are of importance in practice and may therefore inhibit a large-scale expansion of synthetic fuels, although they may play an important role in some sectors, such as aviation or some industrial applications. And finally, large-scale expansion of renewables for synthetic fuel production may, at least in the short-term, increase global emissions due to leakage effects.
