Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-ab...Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-abate emissions and counteract overshooting the earth’s carbon budget.One prospective technology is direct air carbon capture and storage(DACCS),but its energy intensity and costs limit large-scale deployment.Flexible DACCS operation seems promising for cost reduction but yet remains underexplored.This study explores the economic benefits of flexible operation of adsorption-based DACCS,considering fluctuations in both electricity prices and greenhouse gas emissions from the electricity supply.To increase the feasibility of flexible DACCS operation,the typical steam-assisted temperature vacuum swing adsorption cycle is enhanced by introducing two break phases and variable air and steam mass flows during adsorption and desorption.The benefits of flexible operation are comprehensively evaluated using a DACCS system model integrating a detailed dynamic process model with life-cycle greenhouse gas emissions and economic data.The flexible operation allows each cycle to be adjusted to optimally address the time-varying greenhouse gas emissions and costs from electricity supply.A rolling horizon algorithm combined with particle swarm optimization is used to optimize the DACCS cycles in flexible operation mode over one week.The case study focuses on the future German power grid and a DACCS system using amine-functionalized sorbents.Results indicate that flexible DACCS operation can significantly reduce net carbon removal costs by up to 20%compared to a steadystate operation.These findings highlight the potential of flexible DACCS operation to support carbon neutrality efforts by enabling cost-effective carbon dioxide removal through integration with volatile renewable energy systems.展开更多
Adsorption-based direct air carbon capture and storage(DACCS)is an emerging approach to mitigate climate change by removing CO_(2) from the atmosphere.Recent studies show separately that thermodynamic and environmenta...Adsorption-based direct air carbon capture and storage(DACCS)is an emerging approach to mitigate climate change by removing CO_(2) from the atmosphere.Recent studies show separately that thermodynamic and environmental performance strongly depend on regional ambient conditions and energy supply but neglect regional CO_(2) storage potentials.To assess DACCS performance holistically,a detailed global analysis is needed that accounts for the inter-play of regional ambient conditions,energy supply,and CO_(2) storage potential.Hence,we present a novel method for the optimal siting of DACCS plants derived from optimising a dynamic process model that uses global hourly weather data and regionalised data on electricity supply and CO_(2) storage potential.The carbon removal rate(CRR)measures the climate benefit and describes the speed at which a DACCS plant generates net negative emissions.First,we assume that CO_(2) storage is possible everywhere.For four electricity supply scenarios,we show that the opti-mal siting of DACCS significantly increases the CRR when comparing the best and worst locations in each scenario:For a DACCS plant with a nameplate capture capacity of 4 kt CO_(2)y^(-1),the CRR can be increased by 63%from 2.16 to 3.53 kt CO_(2)y^(-1) when using photovoltaic,and by 39%from 2.95 to 4.1 kt CO_(2)y^(-1) when using wind power.Assum-ing a carbon-free electricity supply,the CRR varies between 3.17 and 4.17 kt CO_(2)y^(-1)(32%).Second,we significantly narrow down optimal locations for DACCS considering regional CO_(2) storage potential through CO_(2) mineralisation.Overall,accounting for the interplay of regional DAC performance,energy supply,and CO_(2) storage potential can significantly improve DACCS siting.展开更多
基金This work has been carried out within the project MoGaTEx(01LY2001B)funded by the German Federal Ministry of Education and Research(BMBF)in the founding initiative"KMU-innovativ".
文摘Limiting anthropogenic climate change to below 2°C requires substantial and rapid reductions in greenhouse gas emissions.Additionally,carbon dioxide removal technologies are essential to compensate for hard-to-abate emissions and counteract overshooting the earth’s carbon budget.One prospective technology is direct air carbon capture and storage(DACCS),but its energy intensity and costs limit large-scale deployment.Flexible DACCS operation seems promising for cost reduction but yet remains underexplored.This study explores the economic benefits of flexible operation of adsorption-based DACCS,considering fluctuations in both electricity prices and greenhouse gas emissions from the electricity supply.To increase the feasibility of flexible DACCS operation,the typical steam-assisted temperature vacuum swing adsorption cycle is enhanced by introducing two break phases and variable air and steam mass flows during adsorption and desorption.The benefits of flexible operation are comprehensively evaluated using a DACCS system model integrating a detailed dynamic process model with life-cycle greenhouse gas emissions and economic data.The flexible operation allows each cycle to be adjusted to optimally address the time-varying greenhouse gas emissions and costs from electricity supply.A rolling horizon algorithm combined with particle swarm optimization is used to optimize the DACCS cycles in flexible operation mode over one week.The case study focuses on the future German power grid and a DACCS system using amine-functionalized sorbents.Results indicate that flexible DACCS operation can significantly reduce net carbon removal costs by up to 20%compared to a steadystate operation.These findings highlight the potential of flexible DACCS operation to support carbon neutrality efforts by enabling cost-effective carbon dioxide removal through integration with volatile renewable energy systems.
基金This work has been carried out within the project"DAC-TALES-Transdisciplinary Assessment Combining Labs,the Environment,the Economy,and Society"(01LS2106A)funded by the German Federal Ministry of Education and Research(BMBF).
文摘Adsorption-based direct air carbon capture and storage(DACCS)is an emerging approach to mitigate climate change by removing CO_(2) from the atmosphere.Recent studies show separately that thermodynamic and environmental performance strongly depend on regional ambient conditions and energy supply but neglect regional CO_(2) storage potentials.To assess DACCS performance holistically,a detailed global analysis is needed that accounts for the inter-play of regional ambient conditions,energy supply,and CO_(2) storage potential.Hence,we present a novel method for the optimal siting of DACCS plants derived from optimising a dynamic process model that uses global hourly weather data and regionalised data on electricity supply and CO_(2) storage potential.The carbon removal rate(CRR)measures the climate benefit and describes the speed at which a DACCS plant generates net negative emissions.First,we assume that CO_(2) storage is possible everywhere.For four electricity supply scenarios,we show that the opti-mal siting of DACCS significantly increases the CRR when comparing the best and worst locations in each scenario:For a DACCS plant with a nameplate capture capacity of 4 kt CO_(2)y^(-1),the CRR can be increased by 63%from 2.16 to 3.53 kt CO_(2)y^(-1) when using photovoltaic,and by 39%from 2.95 to 4.1 kt CO_(2)y^(-1) when using wind power.Assum-ing a carbon-free electricity supply,the CRR varies between 3.17 and 4.17 kt CO_(2)y^(-1)(32%).Second,we significantly narrow down optimal locations for DACCS considering regional CO_(2) storage potential through CO_(2) mineralisation.Overall,accounting for the interplay of regional DAC performance,energy supply,and CO_(2) storage potential can significantly improve DACCS siting.
