How replacing fossil fuels with electrofuels could influence the demand for renewable energy and land area

During recent years, electrofuels (fuels from electricity, water, and carbon) have gained increased interest as substitute for fossil fuels in all energy and chemical sectors. The feasibility of electrofuels has been assessed from a range of aspects but no study has assessed the land area needed if scaling up the production based on renewables. The amount of land on Earth is limited and the competition for land, in a long-term perspective, imposes a risk of, e.g., increased food prices and biodiversity losses. The aim of this paper is to assess how much land area it would require if all fossil fuels were substituted by electrofuels (‘All electrofuel’-scenario) and compare this with the area needed if all fossil fuels were substituted by bioenergy (‘All biomass’-scenario) or by electricity (‘All electric’-scenario). Each scenario represents extreme cases towards fully renewable energy systems to outline the theoretical area needed. Main conclusions are (1) the electricity demand, if substituting all fossil fuels with electrofuels, is huge (1540 EJ) but technically obtainable, demanding 1.1% of the Earth's surface, for solar panels, in the most optimistic case, and (2) the sustainable technical potential for biomass cannot alone substitute all fossil fuels, unless radical energy demand reductions.