Desktop version

Home arrow Engineering

  • Increase font
  • Decrease font

<<   CONTENTS   >>

A 2. Cost estimates

These calculations enable us to make cost estimates for Direct Ah' Capture, assuming that the technology applied is similar in nature to the MEA-based post-combustion capture plants reported by Metz et al. (2005). The SRCCS costings, referring to a European or North American location, were adjusted and brought to a consistent 2013-basis by Rubin et al. (2015): some values for Pulverised Coal and Natural Gas combustion power plants are shown in Table Al. Note that these reported costs include compression of the CO, product, but exclude transport and storage.

The engineering duty of these capture plants is represented by the reversible work of separation W (MJ/tCO,), calculated from equation (11), shown in Table Al. Note that the spread in costs around the representative value is about +/- 25%. For process plant of a similar nature, where similar assumptions har e been made in calculating fixed and variable costs, we might expect the performance cost to scale with the duty, and indeed the cost/duty ratio is found to be close to 0.326 US$/MJ(rev work) for both coal and natural gas plants. The reversible work for DAC (Figure 4 in main text) is some 21 MJ/kmolCO,, or 477 MJ/tCO,. Using the scaling described, we might therefore expect the cost of carbon captured by DAC from the air to be about 155 US$/tCO„ exclusive of transport and storage.

Table Al. Scaling cost with reversible work. Range of cost of CO, is given as Low (Representative) High, indicating observed spread. Costs are adjusted SRCCS values, con'ectedto2013 (Rubin et al., 2015), and exclude transport and storage.




W , MJ/tCO,

rev’ 2



Cost of CO, captured, USS/tCO,

33 (48) 58

53 (68) 87

Representative cost of CO, captured, USS/MJ (rev work)



The estimate of 155 USS/tCO, for DAC can be compared with the representative cost of CO, avoided by applying FGC at power plants. At pulverised coal plants the cost of avoided CO, is 67 USS/tCO, so DAC is 88 USS/tCO, (131%) more expensive; at NGCC (gas) plants the cost of avoided CO, is 83 USS/ tCO, so DAC is 72 USS/tCO, (87%) more expensive.

The costs of transport and storage of carbon dioxide will vary with the location, and many other factors relating to specific projects (Metz et al., 2005). Arauge 1-19 USS/tCO, can be taken as consistent with other costs given here (Rubin et al., 2015). An indicative range of cost of DACCS is then 156-174 USS/tCO,.

The amount of carbon dioxide that the DAC process sends to storage can be estimated. We estimate the DAC plant to require heat energy of 14 x Wtev, which is 6678 MJ/tCO,. In addition there is 51 MJ/ kmol or 1159 MJ/tCO, required to din e the compression, thus, 7837 MJ(tli)/tCO, in total. If this energy is derived from natural gas with an emission factor of 0.0561 kg CO,/MJ, then another 440 kg of CO, are generated for every tonne captured from the ah. Assuming 90% of this extra CO, is captured by the DAC plant, the ratio of carbon stored to net carbon captured is (1 + 0.9*0.440)/(l-0.044), which is 1.46. This is similar to the ratio of carbon stored to carbon avoided for coal-fired power plants with post-combustion capture.

A large volume of air must be blown though the DAC contactor where CO, is absorbed, so it is very important that the pressure drop in this device be kept low, to minimise power consumption by the air blowers. The CE DAC process uses a novel structured packing arrangement with intermittent liquid flow (Keith et al., 2018), and its reported pressure drop is about 100 Pa. a very low value. Assuming this pressure drop and a fan efficiency of 70%, the work required is some 11.72 MJ(e)/kmolCO„ or 266 MJ(e)/tCO, when the recovery a is 74.5%. Deriving this work from heat at an efficiency of 40%, gives a requirement for the air blowers of 665 MW(th)/tCO,. This is a fraction 665/7837 of the total heat demand for the DAC process, or 8.5%. We note that in a study of post-combustion capture using MEA at a natural gas fired power plant, the flue gas booster fan required 16% of the energy required for cap true and compression (Smith et al., 2013). The DAC plant estimate is significantly less than this, but does rely on novel low-pressure drop absorption technology. Using a conventional packed contactor would increase the pressure drop, power requirement and cost of DAC.


Allen, M R., Frame, D.J. and Mason, C.F. 2009. The case for mandatory sequestration. Nature Geoscience, 2(12): 813-814.

Astanta, G., Savage, D.W. and Longo, J.M. 1981. Promotion of CO, mass transfer in carbonate solutions. Chemical Engineering Science 36(3): 581-588.

Beerlmg, D J Leake, J.R., Long, S.P., Scholes, J.D., Ton, J., Nelson, P.N., Bird, M., Kantzas, E., Taylor, L.L., Sarkar, B. and Kelland, M. 2018. Fanning with crops and rocks to address global climate, food and soil security. Nature Plants 4: 138-147.

Bellassen, V, Stephan, N., Afriat, M., Alberola, E., Barker, A., Chang, J.P., Chiquet, C., Cochran, I., Deheza, M., Dimopoulos, C. and Foucherot, C. 2015. Monitoring, reporting and verifying emissions in the clnnate economy Native Climate Change 5: 319-328.

Boysen, L.R., Lucht, W., Gerten, D., Heck, V, Lenton, T.M. and Schellnhuber, H.J. 2017. The limits to global-warming mitigation by terrestrial carbon removal. Earth’s Future 5: 463-474.

BP. 201S. BP statistical review of world energy, June 2018.

Ciais, P, Sabine, C., Bala, G., Bopp, L., Brovkin, V, Canadell, J., Chhabra, A., DeFnes, R., Galloway, J., Hermann, M. and Jones, C. 2014. Carbon and other biogeochemical cycles, pp. 465-570. In Clnnate change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Inter-governmental Panel on Climate Change. Cambridge University Press.

Cullinane, J.T. and Rochelle, G.T. 2004. Carbon dioxide absorption with aqueous potassium carbonate promoted by piperazme. Chemical Engineering Science 59(17): 3619-3630.

Danckwerts, P.V. and Sharma, M.M. 1966. The absorption of carbon dioxide into solutions of alkalis and amines (with some notes on hydrogen sulfide and carbonyl sulfide). The Chemical Engineer, October 1966, 244-280.

Eggleston, H.S., Buendia, L., Miwa, K., Ngara, T. and Tanabe, K. 2006. 2006IPCC Guidelines for National Greenhouse Gas Inventories. Chapter 2, Stationary combustion. Japan.

EU. 2014. viewed on 23 May 2019.

Fuss, S., Lamb, W.F., Callaghan, M.W., Hilaire, J., Creutzig, F., Amann, T, Beringer, T., de Oliveira Garcia, W, Hartmann, J., Klianna, T. and Luderer, G. 2018. Negative emissions—Part 2: Costs, potentials and side effects. Environmental Research Letters 13(6): 063002.

Goldthorpe, S. 2017. Potential for very deep ocean storage of CO, without ocean acidification: a discussion paper. Energy Procedia 114: 5417-5429.

Gnscom, B.W., Adams, J., Ellis, P.W., Houghton, R.A. et al. 2017. Natural climate solutions. PNAS 114(44): 11645-11650.

Hanak, D.P., Jenkins, B.G., Kruger, T. and Manovic, V. 2017. High-efficiency negative-carbon emission power generation from integrated solid-oxide fuel cell and calciner. Applied Energy 205: 1189-1201.

ША. 2019. on 23 May 2019.

IPCC. 2018. Summary for policymakers. In Global Warming of 1.5 °C. An IPCC Special Report on the impacts of global wanning of 1.5 °C above pre-industnal levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty. Masson-Delmotte, V, Zhai, P, Portner, H -O , Roberts, D., Skea, J., Shukla, P.R., Pirani, A., Moufouma-Okia, W., Рёап, C., Pidcock, R., Connors, S., Matthew's, J.B.R., Chen, Y., Zhou, X., Gomis, M.I., Lonnoy, E., Maycock, T, Tignor, M. and Wateifield, T. (eds ). World Meteorological Organization, Geneva, Switzerland, 32 pp.

Jackson, S. and Brodal, E. 2018, June. A comparison of the energy consumption for CO, compression process alternatives. In IOP Conference Series: Earth and Environmental Science 167(1): 012031. IOP Publishing.

Keith, D.W., Holmes, G., St Angelo, D. and Heided, K. 2018. A process for capturing CO, from the atmosphere. Joule 2(8): 1573-1594.

Kmg, C.J. 1980. Separation Processes, 2nd edition. McGraw-Hill, New York.

Lai, R, 2011. Sequestering carbon in soils of agio-ecosystems. Food Policy 36: S33-S39.

Mac Dowell, N., Fennell, P.S., Shah, N. and Maitland, G.C. 2017. The role of CO, capture and utilization in mitigating climate change. Nature Climate Change 7(4): 243.

Matthews, H.D., Zickfeld, K., Rnutti, R, and Allen, M.R. 2018. Focus on cumulative emissions, global carbon budgets and the miplications for climate mitigation targets. Environmental Research Letters 13(1): 010201.

Matter, J.M., Stute, M., Snaebjornsdottir, SO., Oelkers, E.H., Gislason, SR., Aradottir, E.S., Sigfusson, B., Gunnarsson, I., Sigurdardottir, H., Gunnlaugsson, E. and Axelsson, G. 2016. Rapid carbon mineralization for permanent disposal of anthropogenic carbon dioxide emissions. Science 352(6291): 1312-1314.

McGlashan, N., Shah, N., Caldecott, B. and Workman, M. 2012. High-level techno-econonuc assessment of negative emissions technologies. Process Safety and Environmental Protection 90(6): 501-510.

McLaren, D. 2012. A comparative global assessment of potential negative emissions technologies. Process Safety and Environmental Protection 90(6): 489-500.

Metz, В , Davidson, О , de Comnck, H, Loos, M. and Meyer, L. 2005. IPCC Special Report on Carbon Dioxide Capture and Storage. Cambridge University Press.

Minx, J.C., Lamb, W.F., Callaghan, M.W., Fuss, S., Hilaire, J., Creutzig, F., Amann, T., Beringer, T., de Oliveira Garcia, W., Hartmann, J. and Khanna, T. 2018. Negative emissions—Part 1: Research landscape and synthesis Environmental Research Letters 13(6): 063001.

National Academies of Sciences, Engineering, and Medicine. 2019. Negative Emissions Technologies and Reliable Sequestration: A Research Agenda. Washington, DC: The National Academies Press.

Nemet, G.F., Callaghan, M.W., Creutzig, F., Fuss, S., Hartmann, J., Hilaire, J,, Lamb, W.F., Minx, J.C., Rogers, S. and Smith, P. 2018. Negative emissions—Part 3: Innovation and upscaling. Environmental Research Letters 13(6): 063003.

Oxburgh, R. 2016. Lowest cost decarbonisation for the UK: The critical role of CCS. Report to the Secretary of State for Business, Energy and Industrial Strategy from the Parliamentary Advisory Group on Carbon Capture and Storage (CCS).

Qambram, N.A., Rahman, M.M., Won, S., Shim, S. and Ra, C. 2017. Biochar properties and eco-friendly applications for climate change mitigation, waste management, and wastewater treatment: A review Renewable and Sustainable Energy Review's 79: 255-273.

Ramezan, M., Skone, T.J., Nsakala, N.Y., Liljedalil, G.N., Gearhart, L.E., Hestennann, R. and Rederstorff, B. 2007. Carbon dioxide capture from existing coal-fired power plants. National Energy Technology Laboratory, DOE/NETL Report, (401/110907).

Rattner, A.S. and Garimella, S. 2011. Energy harvesting, reuse and upgrade to reduce primary energy usage m the USA. Energy 36(10): 6172-6183.

Rau, G.H. 2011. CO, mitigation via capture and chemical conversion in seawater. Environmental Science & Technology 45(3): 1088-1092.

Renforth, P, Jenkins, B.G. and Kruger, T. 2013. Engineering challenges of ocean Inning. Energy 60: 442-452.

Renforth, P. 2019. The negative emission potential of alkaline materials. Nature Communications 10, Article nr 1401.

Rogelj, J., Popp, A., Calvin, K.V., Luderer, G., Emmerling, J., Gemaat, D., Fujimori, S., Strefier, J., Hasegawa, T, Marangom, G. and Krey, V. 2018. Scenarios towards limiting global mean temperature increase below 1.5 °C. Nature Climate Change 8(4): 325-332.

Royal Society and Royal Academy of Engineering. 2018. Greenhouse Gas Removal ISBN: 978-1-78252-349-9.

Rubin, E.S., Davison, IE and Herzog, H.J. 2015. The cost of CO, capture and storage. International Journal of Greenhouse Gas Control 40: 378^100.

Shi, X., Xiao, H., Lackner, K.S. and Chen, X. 2016. Capture CO, fi'om ambient air using nanoconfined ion hydration. Angewandte Chemie-Intemational Edition 55(12): 4026-4029.

Smith, N., Miller, G., Aandi, I., Gadsden, R. and Davison, J. 2013. Performance and costs of CO, capture at gas fired power plants. Energy Procedia 37: 2443-2452.

Smith, R. 2016. Chemical Process: Design and Integration (2nd edition). John Wiley & Sons.

Socolow, R, Desmond, M., Ames, R., Blackstock, J., Bolland, O., Kaarsberg, T., Lewis, N., Mazzotti, M., Pfeffer, A., Sawyer, K. and Siuola, J. 2011. Direct air capture of CO, with chemicals: A technology assessment for the APS Panel on Public Affairs. American Physical Society.

Strefier, J., Amann, T., Bauer, N., Kriegler, E. and Haitmann, J. 2018. Potential and costs of carbon dioxide removal by enhanced weathering of rocks. Environmental Research Letters 13(3): 034010.

UNEP. 2017. The Emissions Gap Report 2017. United Nations Environment Programme (UNEP), Nairobi.

Williamson, P, Wallace, D.W.,Law, C.S., Boyd, P.W., Collos, Y., Croot, P, Denman, K., Riebesell,U.,Takeda, S. and Vivian, C. 2012. Ocean fertilization for geoengineenng: A review of effectiveness, environmental impacts and emerging governance. Process Safety and Environmental Protection 90(6): 475-488.

<<   CONTENTS   >>

Related topics