Current world capacity of hydrocarbon liquefaction is around 400 000 barrels per day, providing a marginal share of the global liquid fuel supply. This study performs a broad review of technical, economic, environmental and supply chain issues related to coal-to-liquids (CTL) and gas-to-liquids (GTL). We find three issues predominate. First, significant amounts of coal and gas would be required to obtain anything more than a marginal production of liquids. Second, the economics of CTL plants are clearly prohibitive, but are better for GTL. Nevertheless, large-scale GTL plants still require very high upfront costs, and for three real-world GTL plants out of four, the final cost has been so far approximately three times that initially budgeted. Small-scale GTL holds potential for associated gas. Third, both CTL and GTL incur significant environmental impacts, ranging from increased greenhouse gas emissions (in the case of CTL) to water contamination. Environmental concerns may significantly affect growth of these projects until adequate solutions are found.
Economic, social and environmental impacts attained by the use of the effluents generated within a small-scale biorefinery concept
