Carbon accounting of negative emissions technologies integrated in the life cycle of spirulina supplements.

Carbon dioxide removal (CDR) technologies are considered essential to accomplish the Paris Agreement targets. Given the important contribution of the food sector to climate change, this study aims to investigate the role of two carbon capture and utilization (CCU) technologies in decarbonizing the production of spirulina, an algae product commonly consumed for its nutritional characteristics. The proposed scenarios considered the replacement of synthetic food-grade CO2 in Arthrospira platensis cultivation (BAU scenario) with CO2 from beer fermentation (BRW) and CO2 from DACC (direct air carbon capture) (SDACC), representing two alternatives with great potential in the short and medium-long term, respectively. The methodology follows the Life Cycle Assessment guidelines, considering a cradle-to-gate scope and a functional unit equivalent to the annual production of spirulina in a Spanish artisanal plant. Results showed a better environmental performance of both CCU scenarios as compared to BAU, reaching a reduction of greenhouse gas (GHG) emissions of 52 % in BRW and of 46 % in SDACC. Although the brewery CCU offers a deeper carbon mitigation of spirulina production, the process cannot reach net zero GHG emissions due to residual burdens across the supply chain. In comparison, the DACC unit could potentially supply both the CO2 needed in spirulina production and work as a CDR to compensate residual emissions, which opens the door for further research on its technical and economic feasibility in the food sector.

Regionalized Strategies for Food Loss and Waste Management in Spain under a Life Cycle Thinking Approach.

Food loss and waste (FLW) has become a central concern in the social and political debate. Simultaneously, using FLW as a bioenergy source could significantly contribute to closing the carbon cycle by reintroducing energy into the food supply chain. This study aims to identify best strategies for FLW management in each of the 17 regions in Spain, through the application of a Life Cycle Assessment. To this end, an evaluation of the environmental performance over time between 2015 and 2040 of five different FLW management scenarios implemented in a framework of (i) compliance and (ii) non-compliance with the targets of the Paris Agreement was performed. Results revealed savings in the consumption of abiotic resources in those regions in which thermal treatment has a strong presence, although their greenhouse gas (GHG) emissions in a scenario of compliance with climate change targets are higher. In contrast, scenarios that include anaerobic digestion and, to a lesser extent those applying aerobic composting, present lower impacts, including climate change, suggesting improvements of 20-60% in non-compliance and 20-80% in compliance with Paris Agreement targets, compared to the current scenarios.

Bringing value to the chemical industry from capture, storage and use of CO2: A dynamic LCA of formic acid production.

Low carbon options for the chemical industry include switching from fossil to renewable energy, adopting new low-carbon production processes, along with retrofitting current plants with carbon capture for ulterior use (CCU technologies) or storage (CCS). In this paper, we combine a dynamic Life Cycle Assessment (d-LCA) with economic analysis to explore a potential transition to low-carbon manufacture of formic acid. We propose new methods to enable early technical, environmental and economic assessment of formic acid manufacture by electrochemical reduction of CO2 (CCU), and compare this production route to the conventional synthesis pathways and to storing CO2 in geological storage (CCS). Both CCU and CCS reduce carbon emissions in particular scenarios, although the uncertainty in results suggests that further research and scale-up validation are needed to clarify the relative emission reduction compared to conventional process pathways. There are trade-offs between resource security, cost and emissions between CCU and CCS systems. As expected, the CCS technology yields greater reductions in CO2 emissions than the CCU scenarios and the conventional processes. However, compared to CCS systems, CCU has better economic potential and lower fossil consumption, especially when powered by renewable electricity. The integration of renewable energy in the chemical industry has an important climate mitigation role, especially for processes with high electrical and thermal energy demands.

Spatial patterns of agricultural expansion determine impacts on biodiversity and carbon storage.

The agricultural expansion and intensification required to meet growing food and agri-based product demand present important challenges to future levels and management of biodiversity and ecosystem services. Influential actors such as corporations, governments, and multilateral organizations have made commitments to meeting future agricultural demand sustainably and preserving critical ecosystems. Current approaches to predicting the impacts of agricultural expansion involve calculation of total land conversion and assessment of the impacts on biodiversity or ecosystem services on a per-area basis, generally assuming a linear relationship between impact and land area. However, the impacts of continuing land development are often not linear and can vary considerably with spatial configuration. We demonstrate what could be gained by spatially explicit analysis of agricultural expansion at a large scale compared with the simple measure of total area converted, with a focus on the impacts on biodiversity and carbon storage. Using simple modeling approaches for two regions of Brazil, we find that for the same amount of land conversion, the declines in biodiversity and carbon storage can vary two- to fourfold depending on the spatial pattern of conversion. Impacts increase most rapidly in the earliest stages of agricultural expansion and are more pronounced in scenarios where conversion occurs in forest interiors compared with expansion into forests from their edges. This study reveals the importance of spatially explicit information in the assessment of land-use change impacts and for future land management and conservation.