Recent global modelling studies suggest a decline of long-distance trade in energy carriers in future global renewable energy systems, compared to today's fossil fuel based system. In contrast, we identify four drivers that facilitate trade of renewable energy carriers. These drivers may lead to trade volumes remaining at current levels or even to an increase during the transition to an energy system with very high shares of renewables. First, new land-efficient technologies for renewable fuel production become increasingly available and technically allow for long-distance trade in renewables. Second, regional differences in social acceptance and land availability for energy infrastructure support the development of renewable fuel import and export streams. Third, the economics of renewable energy systems, i.e. the different production conditions globally and the high costs of fully renewable regional electricity systems, will create opportunities for spatial arbitrage. Fourth, a reduction of stranded investments in the fossil fuel sector is possible by switching from fossil fuels to renewable fuel trade. The impact of these drivers on trade in renewable energy carriers is currently under-investigated by the global energy systems research community. The importance of the topic, in particular as trade can redistribute profits and losses of decarbonization and may hence support finding new partners in climate change mitigation negotiations, warrants further research efforts in this area therefore.

Biofuels are currently the only available bulk renewable fuel. They have, however, limited expansion potential due to high land requirements and associated risks for biodiversity, food security, and land conflicts. We therefore propose to increase output from ethanol refineries in a land-neutral methanol pathway: surplus CO₂-streams from fermentation are combined with H₂ from renewably powered electrolysis to synthesize methanol. We illustrate this pathway with the Brazilian sugarcane ethanol industry using a spatio-temporal model. The fuel output of existing ethanol generation facilities can be increased by 43%–49% or ~100 TWh without using additional land. This amount is sufficient to cover projected growth in Brazilian biofuel demand in 2030. We identify a trade-off between renewable energy generation technologies: wind power requires the least amount of land whereas a mix of wind and solar costs the least. In the cheapest scenario, green methanol is competitive to fossil methanol at an average carbon price of 95€ tCO₂⁻¹.

Wind power is widely recognized as a key component of future net-zero energy systems. However, substantial variability among current wind resource and power simulations used for wind farm deployment limits the reliability of siting and system integration decisions. Therefore, we present a transparent, open source, validated and evaluated, global wind power simulation workflow for the renewable energy simulation tool ETHOS.RESKit . As the first wind simulation workflow using the new Global Wind Atlas 4 and the fifth iteration of the European Center for Medium-Range Weather Forecasts Reanalysis, it is capable of simulating time-resolved energy output of wind turbines with high spatial resolution and customizable designs for both onshore and offshore wind turbines. The tool has undergone an extensive validation and calibration process using over 18 million global measurements from meteorological masts for wind speed bias correction and 8 million measurements from wind turbine sites across 6 countries during 2002 to 2021. In comparison with measured energy yield from wind turbine sites, we achieve a global average capacity factor mean error of 5.6% and Pearson correlation of 0.844. In addition, we evaluate its performance against annually aggregated energy production data from operational wind farms and country-level wind power generation statistics reported by energy agencies, demonstrating its accuracy across multiple spatial and temporal scales with a mean error of only 0.6%. Additionally, a final calibration step ensures alignment of the simulation with real world statistics. The release of ETHOS.RESKit is a step towards a fully open source and open data approach to accurate wind power modeling by incorporating comprehensive simulation advances in one model.