Carbon footprinting of carbon capture and -utilization technologies: discussion of the analysis of Carbon XPRIZE competition team finalists

Life cycle assessments (LCAs) of early-stage technologies can provide valuable insights about key drivers of emissions and aid in prioritizing research into further emissions-reduction opportunities. Despite this potential value, further development of LCA methods is required to handle the increased uncertainty, data gaps, and confidentially of early-stage data. This study presents a discussion of the life cycle carbon footprinting of technologies competing in the final round of the NRG COSIA Carbon XPRIZE competition—a US$20 million competition for teams to demonstrate the conversion of CO2 into valuable products at the scale of a small industrial pilot using consistent deployment conditions, boundaries, and methodological assumptions. This competition allowed the exploration of how LCA can be used and further improved when assessing disparate and early-stage technologies. Carbon intensity estimates are presented for two conversion pathways: (i) CO2 mineralization and (ii) catalytic conversion (including thermochemical, electrochemical, photocatalytic and hybrid process) of CO2, aggregated across teams to highlight the range of emissions intensities demonstrated at the pilot for individual life cycle stages. A future scenario is also presented, demonstrating the incremental technology and deployment conditions that would enable a team to become carbon-avoiding relative to an incumbent process (i.e. reducing emissions relative to a reference pathway producing a comparable product). By considering the assessment process across a diverse set of teams, conversion pathways and products, the study presents generalized insights about opportunities and challenges facing carbon capture and -utilization technologies in their next phases of deployment from a life cycle perspective.

ASSESSMENT OF CARBON FOOTPRINTS OF A TYPICAL NIGERIAN TOWNSHIP POST OFFICE: A CASE STUDY OF KAFANCHAN DISTRICT POST OFFICE, KAFANCHAN, NIGERIA

This research work focuses on carbon footprinting the operations of a township post office in a developing country. The analysis was carried out in accordance with the Universal Postal Union’s guidelines for carbon accounting. The results showed that for the inventory year, the office’s carbon footprint was 13.3423 tonnes of carbon dioxide equivalent (CO2e). It was found that for each gram of parcel delivered, 0.0171 kgCO2e was emitted into the atmosphere. Results further showed that 82 % of emission is attributed to delivery of mails while 18 % is as a result of sorting and other minor activities within the facility.

Carbon Accounting for Regenerative Cities

The carbon budget for limiting global warming to the targeted 1.5 ° is running out. Cities have a central role in climate change mitigation, as the vast majority of all greenhouse gas emissions occur to satisfy the energy and material needs of cities and their residents. However, cities typically only account for their direct local emissions from transportation, industry, and energy production. This may lead to the so-called low-carbon illusion of cities following from producing little and reporting low emissions, while extensively relying on imported material and energy flows. Consumption-based accounting, or carbon footprinting, enables overcoming this problem by assigning the emissions to the end user regardless of the place of production. However, currently the carbon footprinting methods only capture the harm side, and not the potential positive effects, the restorative or regenerative impacts, caused by green infrastructure, reforestation, and carbon capture and storage, for example. These positive impacts are sometimes called “carbon handprint”. In this chapter, we create a handprint-extended carbon footprinting method to illustrate how restorative and regenerative impacts can be incorporated consistently in the carbon accounting of cities and carbon footprints of consumers. We also link the discussion on regenerative cities with the remaining carbon budgets.