Chapter 2: A High-level Analysis of the Environmental Sustainability of Biomass-derived Fuels
Published:18 Nov 2022
J. A. Fox, in Chemicals and Fuels from Biomass via Fischer–Tropsch Synthesis
Download citation file:
In this chapter, fundamental concepts based on conservation of mass and conservation of energy are applied to answer two main questions: firstly, how environmentally sustainable are biomass-to-liquid processes when taking carbon emissions from the process into account, and secondly, what would it take to construct a completely sustainable biomass-to-liquid process? The analysis in this chapter determines that a process that produces 140 000 barrels of liquid fuel a day would require that around 80 000 km2 of forest be cultivated in order to achieve complete carbon neutrality. While this is a very large area of land, it is still comparable to the largest farms that currently exist. If the analysis is extended to achieving carbon neutrality for the entire planet's oil usage, 14 million km2 of land is needed for energy crops. However, only 10 million km2 of land is actually available for energy crops. Biofuels, on their own, are therefore not going to solve the problem of environmental sustainability although they are definitely part of the solution. In contrast, there is no chance of environmental sustainability if the current over-reliance on fossil fuels continues. Biomass can capture at least some of the carbon emissions from processes or other human activities, which is better than not capturing any of the emitted carbon dioxide at all.