Natural Gas vs. Electricity for Solvent-Based Direct Air Capture
Removing CO2 from the air with chemicals (Direct Air Capture, DAC) requires a significant amount of energy. Here, we evaluate the cost of co-constructing a solvent DAC process with its energy system. We compare eight energy systems paired with two alternative designs for a liquid-solvent DAC system...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Frontiers Media S.A.
2021-01-01
|
| Series: | Frontiers in Climate |
| Subjects: | |
| Online Access: | https://www.frontiersin.org/articles/10.3389/fclim.2020.618644/full |
| _version_ | 1818615949852409856 |
|---|---|
| author | Noah McQueen Michael J. Desmond Robert H. Socolow Peter Psarras Jennifer Wilcox |
| author_facet | Noah McQueen Michael J. Desmond Robert H. Socolow Peter Psarras Jennifer Wilcox |
| author_sort | Noah McQueen |
| collection | DOAJ |
| description | Removing CO2 from the air with chemicals (Direct Air Capture, DAC) requires a significant amount of energy. Here, we evaluate the cost of co-constructing a solvent DAC process with its energy system. We compare eight energy systems paired with two alternative designs for a liquid-solvent DAC system capturing 1 MtCO2/year, which requires roughly 240 to 300 megawatts of steady power equivalent, 80% thermal and 20% electric. Two energy systems burn natural gas onsite for heat and electricity, capturing nearly all the CO2 released during combustion, and six are all-electric non-fossil systems. The cost of the DAC facility alone contributes $310/tCO2 for a conventional process-based design and $150/tCO2 for a more novel design. When the decomposition of calcium carbonate occurs within a natural-gas-heated calciner, the energy system adds only $80/tCO2 to these costs, assuming $3.25/GJ ($3.43/MMBtu) gas. However, leakage in the natural gas supply chain increases the cost of net capture dramatically: with 2.3% leakage (U.S. national average) and a 20-year Global Warming Potential of 86, costs are about 50% higher. For the all-electric systems, the total capture cost depends on the electricity cost: for each $/MWh of levelized cost of electricity, the total capture cost increases by roughly $2/tCO2. Continuous power is required, because the high-temperature calciner cannot be cycled on and off, so solar and wind power must be supplemented with storage. Our representative capture costs are $250–$440/tCO2 for geothermal energy, $370–$620/tCO2 for nuclear energy (two variants–a light water reactor and small modular nuclear), $360–$570/tCO2 for wind, $430–$690/tCO2 for solar photovoltaics (two variants assuming different daily solar capacities), and $300–$490/tCO2 for a hybrid system with a natural-gas-powered electric calciner. |
| first_indexed | 2024-12-16T16:42:02Z |
| format | Article |
| id | doaj.art-d88ebe050b464250b87af73028e5720f |
| institution | Directory Open Access Journal |
| issn | 2624-9553 |
| language | English |
| last_indexed | 2024-12-16T16:42:02Z |
| publishDate | 2021-01-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Climate |
| spelling | doaj.art-d88ebe050b464250b87af73028e5720f2022-12-21T22:24:16ZengFrontiers Media S.A.Frontiers in Climate2624-95532021-01-01210.3389/fclim.2020.618644618644Natural Gas vs. Electricity for Solvent-Based Direct Air CaptureNoah McQueen0Michael J. Desmond1Robert H. Socolow2Peter Psarras3Jennifer Wilcox4Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA, United StatesIndependent Consultant, Goodyear, AZ, United StatesDepartment of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ, United StatesDepartment of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA, United StatesDepartment of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, PA, United StatesRemoving CO2 from the air with chemicals (Direct Air Capture, DAC) requires a significant amount of energy. Here, we evaluate the cost of co-constructing a solvent DAC process with its energy system. We compare eight energy systems paired with two alternative designs for a liquid-solvent DAC system capturing 1 MtCO2/year, which requires roughly 240 to 300 megawatts of steady power equivalent, 80% thermal and 20% electric. Two energy systems burn natural gas onsite for heat and electricity, capturing nearly all the CO2 released during combustion, and six are all-electric non-fossil systems. The cost of the DAC facility alone contributes $310/tCO2 for a conventional process-based design and $150/tCO2 for a more novel design. When the decomposition of calcium carbonate occurs within a natural-gas-heated calciner, the energy system adds only $80/tCO2 to these costs, assuming $3.25/GJ ($3.43/MMBtu) gas. However, leakage in the natural gas supply chain increases the cost of net capture dramatically: with 2.3% leakage (U.S. national average) and a 20-year Global Warming Potential of 86, costs are about 50% higher. For the all-electric systems, the total capture cost depends on the electricity cost: for each $/MWh of levelized cost of electricity, the total capture cost increases by roughly $2/tCO2. Continuous power is required, because the high-temperature calciner cannot be cycled on and off, so solar and wind power must be supplemented with storage. Our representative capture costs are $250–$440/tCO2 for geothermal energy, $370–$620/tCO2 for nuclear energy (two variants–a light water reactor and small modular nuclear), $360–$570/tCO2 for wind, $430–$690/tCO2 for solar photovoltaics (two variants assuming different daily solar capacities), and $300–$490/tCO2 for a hybrid system with a natural-gas-powered electric calciner.https://www.frontiersin.org/articles/10.3389/fclim.2020.618644/fulldirect air capture (DAC)negative emissions technologies (NETs)carbon capturecarbon dioxide removal (CDR)energy resourcestechnoeconomic analysis (TEA) |
| spellingShingle | Noah McQueen Michael J. Desmond Robert H. Socolow Peter Psarras Jennifer Wilcox Natural Gas vs. Electricity for Solvent-Based Direct Air Capture Frontiers in Climate direct air capture (DAC) negative emissions technologies (NETs) carbon capture carbon dioxide removal (CDR) energy resources technoeconomic analysis (TEA) |
| title | Natural Gas vs. Electricity for Solvent-Based Direct Air Capture |
| title_full | Natural Gas vs. Electricity for Solvent-Based Direct Air Capture |
| title_fullStr | Natural Gas vs. Electricity for Solvent-Based Direct Air Capture |
| title_full_unstemmed | Natural Gas vs. Electricity for Solvent-Based Direct Air Capture |
| title_short | Natural Gas vs. Electricity for Solvent-Based Direct Air Capture |
| title_sort | natural gas vs electricity for solvent based direct air capture |
| topic | direct air capture (DAC) negative emissions technologies (NETs) carbon capture carbon dioxide removal (CDR) energy resources technoeconomic analysis (TEA) |
| url | https://www.frontiersin.org/articles/10.3389/fclim.2020.618644/full |
| work_keys_str_mv | AT noahmcqueen naturalgasvselectricityforsolventbaseddirectaircapture AT michaeljdesmond naturalgasvselectricityforsolventbaseddirectaircapture AT roberthsocolow naturalgasvselectricityforsolventbaseddirectaircapture AT peterpsarras naturalgasvselectricityforsolventbaseddirectaircapture AT jenniferwilcox naturalgasvselectricityforsolventbaseddirectaircapture |