In the quest to mitigate climate change, the energy sector is increasingly turning to carbon capture technologies. However, a new study published by researchers at Chalmers University of Technology in Sweden has shed light on a critical yet often overlooked aspect: the cost and energy implications of producing the chemical solvents and sorbents essential for these technologies.
The research, led by V Chanal from the Department of Space, Earth and Environment, focuses on three key chemical sorbents used in carbon capture: monoethanolamine (MEA) for post-combustion carbon capture, potassium hydroxide (KOH) for liquid direct air capture (DAC), and polyethylenimine-silica (PEI) for solid sorbent DAC. The findings, published in the journal Environmental Research Letters (translated from Swedish as ‘Letters on Environmental Research’), reveal significant implications for the energy system’s cost, energy use, and material demand.
Chanal and his team found that the production of these sorbents could substantially impact the overall energy system, particularly when scaled up. “The production of chemical sorbents could have significant implications on system cost, energy use, and material use depending on how much they are consumed,” Chanal explained. This is particularly true for solid sorbents used in DAC, which showed the highest uncertainties in the system.
The study highlights that at the high end of solid sorbent consumption, the total energy system cost could increase by up to 6.5%. While the effects for other sorbents like MEA and KOH were small to negligible, the scale-up of material production capacities was substantial for MEA and PEI. This scale-up is crucial for meeting the growing demand for carbon capture technologies, but it also presents significant challenges.
One of the key trade-offs identified in the study is between the advantages of using PEI, which requires a lower sorbent regeneration temperature than KOH, and the potential production costs. “There is thus a trade-off between the advantages and the additional cost uncertainty regarding sorbents,” Chanal noted. This trade-off is particularly relevant for the energy sector, where cost-efficiency and operational feasibility are paramount.
The research underscores the need for a more thorough consideration of sorbent consumption in scenarios relying on solid sorbent DAC. As the energy sector continues to explore and implement carbon capture technologies, understanding these nuances will be crucial for developing sustainable and cost-effective solutions.
The implications of this study are far-reaching. For energy companies investing in carbon capture technologies, the findings highlight the importance of factoring in the cost and energy demands of sorbent production. For policymakers, it emphasizes the need for supportive frameworks that encourage innovation in sorbent production and reduce uncertainties in the supply chain.
As the energy sector navigates the complexities of carbon capture, this research provides a valuable roadmap for stakeholders. By addressing the challenges associated with sorbent production, the industry can move closer to achieving its climate mitigation goals while ensuring economic viability. The study, published in Environmental Research Letters, serves as a call to action for the energy sector to prioritize the sustainable production of chemical sorbents, paving the way for a greener future.
