Scoping carbon dioxide removal options for Germany–What is their potential contribution to Net-Zero CO2?

Abstract

In its latest assessment report the IPCC stresses the need for carbon dioxide removal (CDR) to counterbalance residual emissions to achieve net zero carbon dioxide or greenhouse gas emissions. There are currently a wide variety of CDR measures available. Their potential and feasibility, however, depends on context specific conditions, as among others biophysical site characteristics, or availability of infrastructure and resources. In our study, we selected 13 CDR concepts which we present in the form of exemplary CDR units described in dedicated fact sheets. They cover technical CO2 removal (two concepts of direct air carbon capture), hybrid solutions (six bioenergy with carbon capture technologies) and five options for natural sink enhancement. Our estimates for their CO2 removal potentials in 2050 range from 0.06 to 30 million tons of CO2, depending on the option. Ten of the 13 CDR concepts provide technical removal potentials higher than 1 million tons of CO2 per year. To better understand the potential contribution of analyzed CDR options to reaching net-zero CO2 emissions, we compare our results with the current CO2 emissions and potential residual CO2 emissions in 2050 in Germany. To complement the necessary information on technology-based and hybrid options, we also provide an overview on possible solutions for CO2 storage for Germany. Taking biophysical conditions and infrastructure into account, northern Germany seems a preferable area for deployment of many concepts. However, for their successful implementation further socio-economic analysis, clear regulations, and policy incentives are necessary.

Dynamics of bio-based carbon dioxide removal in Germany

“…In contrast, capturing CO2 from a flue gas stream with a concentration of about 10-15 % CO2 increases expenses (Baylin-Stern and Berghout 2021). The calculated values are within the ranges given in the literature for different BECCS processes (Borchers et al 2022;Fuss et al 2018;Irlam 2017), which vary widely due to the multitude of cost influencing factors, including infrastructure availability for transport and storage and storage distances. Further cost assessments, which also compare BECCS costs to fossil-based CCS, are needed (Stavrakas et al 2018).…”

“…Based on the definition by Borchers et al (2022), the CAPEX (Capital Expenditures) include all longer-term investments (e.g. for construction, machinery, buildings, initial equipment, etc.)…”

On the path to net-zero: Establishing a multi-level system to support the complex endeavor of reaching national carbon neutrality

“…Considering specifically the evaluation of feasibility of CO 2 removal technologies, two tools have been developed in the Net-Zero-2050 project: So-called "model concepts" of CDR options (Borchers et al, 2022) and a comprehensive CDR assessment framework . The CDR assessment framework has been built upon the previous feasibility assessment of bioenergy strategies in Germany (Thrän et al, 2020).…”

“…There is a wide range of CDR methods and corresponding implementation options, ranging from natural sink enhancement to technological and chemical approaches (Borchers et al, 2022;IPCC, 2022a). All of them have in common that they describe human activities removing CO 2 from the atmosphere and storing it temporarily or permanently in terrestrial, geological or marine reservoirs as well as in long-lived products (IPCC, 2022a).…”

“…The Net-Zero-2050 project, Cluster I of the Helmholtz Climate Initiative, has therefore set itself the task of underpinning Germany's path toward carbon neutrality with scientific evidence. The project results included the calculation of national CDR potentials (Borchers et al, 2022;Mengis et al, 2022) and associated implementation recommendations as well as the design of an energy system transformation path in agreement with a predefined 1.5 • C-budget for Germany (Simon et al, 2022). As an overarching action step, the Net-Zero-2050 System was developed to comprehend the anthropogenic systems that need to be transformed in order to achieve national carbon neutrality.…”