Techno-economic evaluation of microalgae high-density liquid fuel production at 12 international locations

Abstract

Background Microalgae-based high-density fuels offer an efficient and environmental pathway towards decarbonization of the transport sector and could be produced as part of a globally distributed network without competing with food systems for arable land. Variations in climatic and economic conditions significantly impact the economic feasibility and productivity of such fuel systems, requiring harmonized technoeconomic assessments to identify important conditions required for commercial scale up. Methods Here, our previously validated Techno-economic and Lifecycle Analysis (TELCA) platform was extended to provide a direct performance comparison of microalgae diesel production at 12 international locations with variable climatic and economic settings. For each location, historical weather data, and jurisdiction-specific policy and economic inputs were used to simulate algal productivity, evaporation rates, harvest regime, CapEx and OpEx, interest and tax under location-specific operational parameters optimized for Minimum Diesel Selling Price (MDSP, US$ L−1). The economic feasibility, production capacity and CO2-eq emissions of a defined 500 ha algae-based diesel production facility is reported for each. Results Under a for-profit business model, 10 of the 12 locations achieved a minimum diesel selling price (MDSP) under US$ 1.85 L−1 / US$ 6.99 gal−1. At a fixed theoretical MDSP of US$ 2 L−1 (US$ 7.57 gal−1) these locations could achieve a profitable Internal Rate of Return (IRR) of 9.5–22.1%. Under a public utility model (0% profit, 0% tax) eight locations delivered cost-competitive renewable diesel at an MDSP of < US$ 1.24 L−1 (US$ 4.69 gal−1). The CO2-eq emissions of microalgae diesel were about one-third of fossil-based diesel. Conclusions The public utility approach could reduce the fuel price toward cost-competitiveness, providing a key step on the path to a profitable fully commercial renewable fuel industry by attracting the investment needed to advance technology and commercial biorefinery co-production options. Governments’ adoption of such an approach could accelerate decarbonization, improve fuel security, and help support a local COVID-19 economic recovery. This study highlights the benefits and limitations of different factors at each location (e.g., climate, labour costs, policy, C-credits) in terms of the development of the technology—providing insights on how governments, investors and industry can drive the technology forward. Graphic abstract

Recent Advances in Algae-Derived Biofuels and Bioactive Compounds

“…According to LCA studies by Ketzer et al, 119 a vast variation of energy return on investment (EROI) ranges from 0.01 to 3.35, and energy input optimization in cultivation, harvesting, and downstream processing was required to make the biorefinery process profitable, and the difficulties in LCA of heterotrophic algae and yeast were the lack of data on industrial-scale production, especially for the feedstock processing and cultivation. 120 Roles et al 121 adopted a validated Techno-economic and Life Cycle Analysis (TELCA) (Figure 8) to compare the performance of • High biomass production and antioxidant capability of biomass were achieved using a mesh ultrathin layer photobioreactor. 122 • This new bioreactor led to a high environmental impact on the biomass production, while a lower environmental impact on the antioxidant production was observed.…”

“…According to LCA studies by Ketzer et al, a vast variation of energy return on investment (EROI) ranges from 0.01 to 3.35, and energy input optimization in cultivation, harvesting, and downstream processing was required to make the biorefinery process profitable, and the difficulties in LCA of heterotrophic algae and yeast were the lack of data on industrial-scale production, especially for the feedstock processing and cultivation . Roles et al adopted a validated Techno-economic and Life Cycle Analysis (TELCA) (Figure ) to compare the performance of algal biodiesel production in 12 locations under various climatic and economic settings. The capital expenditure (CAPEX) and annual OPEX for these 12 facilities with a size of 500 ha were US$ 128–245 million and US$ 7.7–16.4 million, respectively.…”

Integration of Microalgae‐Based Wastewater Bioremediation–Biorefinery Process to Promote Circular Bioeconomy and Sustainability: A Review

“…The analysis revealed that a minimum diesel selling price below US$1.85 L −1 and a profitable internal rate of return of up to 22.1% could be achieved at ten locations. [ 91 ]…”

“…The analysis revealed that a minimum diesel selling price below US$1.85 L −1 and a profitable internal rate of return of up to 22.1% could be achieved at ten locations. [91] Microalgal biorefinery value chains for industrial products were developed and validated for four industrial microalgal strains. Both single product value chains (SP) and multiproduct value chains (MP) were evaluated for their techno-economic performance and cost-revenue optimization was undertaken.…”

Exploiting photosynthesis-driven P450 activity to produce indican in tobacco chloroplasts

“…Plants also offer the enticing possibility of coupling biochemical production directly to the assimilation of light energy and carbon via photosynthesis; truly green chemistry ( Sørensen et al., 2022 ). Recent thorough techno-economic analyses have shown that bio-fuel manufacturing in photosynthetic algae can be economically viable given optimal environmental conditions, especially if co-products such as protein can be extracted in parallel from the same strain ( Roles et al., 2021 ; Karan et al., 2022 ). This offers hope that with proper design and optimization, production of high value molecules through metabolic engineering in plants could prove economically feasible in the future.…”