Periodic Reporting for period 4 - reFUEL (Going global? Renewable fuel trade and social land-use restrictions in a low-carbon energy system)
Berichtszeitraum: 2023-02-01 bis 2024-01-31
Energy systems are responsible for a large share of global greenhouse gas emissions as they cause substantial fossil fuel consumption. Synthetic fuels are one potential way of reducing fossil fuels use. They are produced from (renewable) hydrogen and, possibly, carbon dioxide and can be used in energy systems similarly to fossil fuels. They can also be, in principle, transported over long distances, allowing for trade of such fuels between countries. While it is apparent that electrification of transport, heating and most industrial processes is the most cost and land-use efficient way of reducing fossil fuel emissions, synthetic fuels may serve an important role in some sectors. However, research on how and where such synthetic fuels will be produced in the future is scarce. In particular, current assessments do not take into account the competition for and conflicts about land used for renewables in a theoretically and empirically convincing way. Furthermore, climate data used to simulate renewable energy output has not been validated consistently for different world regions, and productin schemes for synthetic fuels have not been assessed in detail. In the reFUEL project, we therefore aimed at developing the basics for sound assessments of future synthetic fuel streams, (1) assessing how the wider land-related impacts of the expansion of renewables can be understood, contrasting case studies in Brazil and Europe, analyzed from different disciplinary perspectives, (2) understanding the quality of climate data used for simulating renewable energies, and (3) understanding core characteristics of future synthetic-fuel production systems. Thus, we aimed at developing a holistic understanding of the challenges of future synthetic fuel produciton and trade streams.
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.
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.
We see three major contributions beyond the state-of-the-art in our project: first, the current practice for determining the potentials for building renewable energies is to derive exclusion zones. However, the criteria used for defining these zones are often subjective, lack empirical and theoretical support, and additionally fail to reflect relevant economic trade-offs due to their binary classification. We therefore have developed a new methodology to reveal the social cost of wind power plants implicit in authorities' planning decisions. This approach allows to integrate the full benefits and costs of deploying renewable energy technologies at a certain location into a power system model. Thereby, it corrects a crucial shortcoming of these models, which are widely used in power system planning and policy development. It also shows that public administration assigns significant external costs to wind turbines.
Second, the current practice of defining exclusion zones for renewables can also be criticized as the criteria often exclude perspectives of traditional communities and land-users, especially in the Global South. We found in our case studies that conflicts between developers and rural populations are considerable, and that renewable energy projects in many instances are linked to privatization of public land and the withdrawal of traditional user rights. We also linked Brazilian data on how land is owned with a database on global investments in renewable energy projects, highlighting how international capital, mainly from Europe, is involved in land privatizations.
Third, we have developed a new method for understanding which factors affect growth in wind power generation. We can clearly differentiate how the number of turbines, the size of rotors, tower height, and the quality of wind at the location of turbines affects overall output. We could thus show how wind is used at lower technical efficiency today than a decade ago, but that, at the same time, the output per area swept by the turbine rotors has increased, because turbines today are much higher than a decade ago.
Second, the current practice of defining exclusion zones for renewables can also be criticized as the criteria often exclude perspectives of traditional communities and land-users, especially in the Global South. We found in our case studies that conflicts between developers and rural populations are considerable, and that renewable energy projects in many instances are linked to privatization of public land and the withdrawal of traditional user rights. We also linked Brazilian data on how land is owned with a database on global investments in renewable energy projects, highlighting how international capital, mainly from Europe, is involved in land privatizations.
Third, we have developed a new method for understanding which factors affect growth in wind power generation. We can clearly differentiate how the number of turbines, the size of rotors, tower height, and the quality of wind at the location of turbines affects overall output. We could thus show how wind is used at lower technical efficiency today than a decade ago, but that, at the same time, the output per area swept by the turbine rotors has increased, because turbines today are much higher than a decade ago.