Simon Schäfer (Theme 3)
The target of a sustainable world is still to reduce the amount of CO2, but for some industries it’s not possible to reduce the amount of CO2 to net-zero. For this problem CCU could play an important role to reuse the emitted carbon dioxide for industrial processes. This blog introduces the CCU-System and explains challenges in terms of the system.
Introduction
Until 2050, the society should be CO2 neutral. Generally, this is possible if more electrical energy and renewable energies are used. For the chemical industry it is more difficult than in other sectors due to the use of raw materials. For example, polymers and medicines contains carbon out of oil or gas. After the use of these products the CO2 is released through combustion. An approach to reuse the released CO2 which is captured from the air is Carbon Capture and Utilisation (Marzotti, 2022).
Figure 1: Different net zero solutions, CCU in red frame (Gabrielli et al., 2020)
The function of the system is shown in Figure 1. Carbon Capture and Utilisation takes the carbon dioxide from the atmosphere, the Carbon dioxide goes through a chemical process to provide again carbon (Carbon based product) for the industry. The cycle could be closed by capturing CO2, the carbon is in a cycle and thus no new non-renewable products need to be used. This is possible if renewable energy sources are used to operate the plant, otherwise it would affect the climate change negatively. Additionally, the CO2 can be used directly (without synthesis), e.g. for fire extinguisher or indirectly through synthesis of basic chemicals for the chemical industry (Umweltbundesamt, 2021). The indirect method is referred to as power to gas/liquid/solid.
ChallengesDue to an analysis of the CCU-System (acatech, 2018, p. 24), CO2 is very stable molecule and reactions with CO2 needs a big amount of energy (e.g. electrical energy). Therefore, a requirement is to generate a big amount (much bigger than now produced in Europe) of renewable electrical energy. This is not possible with the power-mix of today, so the main part to provide a CCU, which not additionally affects the environment, is to have a minimum of 80% of renewable electrical energy (Umweltbundesamt, 2021). Below is a graphic showing the current amount of renewable electricity compared to the amount needed to recycle 210 million tonnes of CO2. The maximal amount of 210 tonnes was derived from the acatech report (acatech, 2018, p. 28) and is associated with an annual investment of 27 billion euros.
Figure 2: Amount of (Renewable) electrical energy in Europe compared to the required amount of electrical energy to recycle 210 million tonnes of CO2
The calculated electrical costs for recycling 1 ton of CO2 (Amount of electrical consumption from (acatech, 2018, p. 28):
4.9*10^12 KWh/210 Mio ton*0.3 €/KWh (Approx. costs of 1 KWh in Germany (CO2 Online, 2022)) = 12’250 €
Compared to the calculated costs for the synthesis of 1 ton MeOH (CCU-DAC), (Amount of electrical consumption from Gabrielli et al., 2020, p. 7041):
10’000 KWh/tMeOH*0.3 €/KWh (Approx. costs of 1 KWh in Germany (CO2 Online, 2022))= 3000 €
Of course, this calculation cannot be taken over directly, as the electricity price is also made up of taxes etc. and a different calculation would result for an introduction of CCU. However, it should be shown that CCU would result in considerable costs. Furthermore the report from acatech (acatech, 2018, p. 26) showed that there are economic challenges for the implementation of CCU’s: The economic viability of manufacturing products based on CO2 depends largely on the added value of the products generated and on the regulatory framework.
Cost reduction is only possible if the cost of electricity is reduced. Therefore, the production of chemical products with raw materials (gas, oil) is currently much cheaper than through synthesis and the electricity required for this. If the chemical substances are now produced through synthesis, this results in a cost increase of over 100% compared to production through non-renewable raw materials (acatech, 2018, p. 26).
Conclusion
There are several challenges for the CCU system. In summary, the following points are currently preventing the introduction of CCU: The price of renewable electrical energy, the amount of renewable electrical energy, hurdles through regulations, economy aspects and large investments which are needed (from government and companies). The most important thing is still to reduce CO2 emissions, but CCUs will be extremely important in the future to claim the net zero goal. Especially for industries that are dependent on carbon so that the emitted CO2 can also be recycled in these processes and be integrated into a closed loop. The implementation of Carbon Capture and Utilisation includes effects such as the adaptation of the manufacturing process and the provision of renewable electrical energy. Science has shown that the system works, but it also needs the companies to be aware of the situation and willing to generate support (financial and the adaptation of the manufacturing processes). This certainly involves large investments but can have a major impact on sustainability later on. In addition, it’s very important that the prices of electrical energy are reduced and as many renewable energies are provided as possible in the next years. The blog shows that the implementation depends on various aspects which must be considered that a solution can be found, it specifically involves carbon product manufacturers, electrical energy providers, policy makers and scientists in the field of CCU. With these points it’s possible to build CCU’s and to make another step in the right direction.
Bibliography
acatech (2018). CCU und CCS: Bausteine für den Klimaschutz in der Industrie. https://www.wwf.de/fileadmin/fm-wwf/Publikationen- PDF/CCU_und_CCS_Bausteine_fuer_den_Klimaschutz_in_der_Industrie.pdf (16.04.2022).
CO2 Online. (2022). Strompreisentwicklung: Das kostet 1 kWh Strom 2022. https://www.co2online.de/energie- sparen/strom-sparen/strom-sparen-stromspartipps/strompreis/ (16.04.2022).
Gabrielli, P., Gazzani, M. & Mazotti, M. (2020). The Role of Carbon Capture and Utilization, Carbon Capture and Storage, and Biomass to Enable a Net-Zero-CO2 Emissions Chemical Industry. https://pubs.acs.org/doi/pdf/10.1021/acs.iecr.9b06579 (16.04.2022).
Marzotti, M. (2022, 6. April). CLIMATE CHANGE, DECARBONIZATION, AND SUSTAINABLE INDUSTRY: The role of CCS and CCU. ETH Zürich, Online.
Umweltbundesamt. (2021). Carbon Capture and Utilization (CCU). https://www.umweltbundesamt.de/themen/klima-energie/klimaschutz-energiepolitik-in- deutschland/carbon-capture-utilization-ccu#Fazit (16.04.2022).