Restoring Pre-Industrial CO2 Levels While Achieving Sustainable Development Goals

Abstract

Unless humanity achieves United Nations Sustainable Development Goals (SDGs) by 2030 and restores the relatively stable climate of pre-industrial CO2 levels (as early as 2140), species extinctions, starvation, drought/floods, and violence will exacerbate mass migrations. This paper presents conceptual designs and techno-economic analyses to calculate sustainable limits for growing high-protein seafood and macroalgae-for-biofuel. We review the availability of wet solid waste and outline the mass balance of carbon and plant nutrients passing through a hydrothermal liquefaction process. The paper reviews the availability of dry solid waste and dry biomass for bioenergy with CO2 capture and storage (BECCS) while generating Allam Cycle electricity. Sufficient wet-waste biomass supports quickly building hydrothermal liquefaction facilities. Macroalgae-for-biofuel technology can be developed and straightforwardly implemented on SDG-achieving high protein seafood infrastructure. The analyses indicate a potential for (1) 0.5 billion tonnes/yr of seafood; (2) 20 million barrels/day of biofuel from solid waste; (3) more biocrude oil from macroalgae than current fossil oil; and (4) sequestration of 28 to 38 billion tonnes/yr of bio-CO2. Carbon dioxide removal (CDR) costs are between 25–33% of those for BECCS with pre-2019 technology or the projected cost of air-capture CDR.

Nearshore Macroalgae Cultivation for Carbon Sequestration by Biomass Harvesting: Evaluating Potential and Impacts with An Earth System Model

“…Governance and societal facets need consideration in macroalgae-based CDR, particularly due to potential spatial competition between macroalgae cultivation and fisheries, especially along the Peruvian coast Merk et al, 2022). A Comprehensive Life Cycle Analysis (LCA) considering energy consumption biomass conversion efficiency, and financial cost is pivotal Melara et al, 2020;Capron et al, 2020;.…”

The Potential for Ocean-Based Climate Action: Negative Emissions Technologies and Beyond

“…The latter is expected to involve three overarching steps: increasing carbon uptake by macroalgal aquaculture; converting the biomass to biofuel; and deploying carbon capture (at power stations) and long-term geological storage. Capron et al (2020) review recent progress by US researchers in using macroalgae for biofuel.…”

Thermodynamic Analysis of Negative CO2 Emission Power Plant Using Aspen Plus, Aspen Hysys, and Ebsilon Software

“…Such a concept is important, not only from the point of view of negative CO 2 emissions, but also from the point of view of limiting the curtailment of energy generation using intermittent renewable energy sources [23], as flexibility is critical for power systems with high shares of intermittent renewable energy sources (solar, wind) [24][25][26][27][28]. Capron et al [29] focused on the use of Allam Cycle for achieving carbon negative emissions. A comprehensive overview, as presented in that paper, suggested that CCS could be combined with growing seafood, its subsequent processing, and production of biofuels, resulting in simultaneous increase in productivity and decrease in the exploited surface of the oceans, thus increasing the overall areas dedicated to conservation of biodiversity [29].…”

“…Capron et al [29] focused on the use of Allam Cycle for achieving carbon negative emissions. A comprehensive overview, as presented in that paper, suggested that CCS could be combined with growing seafood, its subsequent processing, and production of biofuels, resulting in simultaneous increase in productivity and decrease in the exploited surface of the oceans, thus increasing the overall areas dedicated to conservation of biodiversity [29].…”