The study presents the results of an integrated assessment of carbon capture and storage (CCS) in the power plant sector in Germany, with special emphasis on the competition with renewable energy technologies. Assessment dimensions comprise technical, economic and environmental aspects, long-term scenario analysis, the role of stakeholders and public acceptance and regulatory issues. The results lead to the overall conclusion that there might not necessarily be a need to focus additionally on CCS in the power plant sector. Even in case of ambitious climate protection targets, current energy policy priorities (expansion of renewable energies and combined heat and power plants as well as enhanced energy productivity) result in a limited demand for CCS. In case that the large energy saving potential aimed for can only partly be implemented, the rising gap in CO2 reduction could only be closed by setting up a CCS-maximum strategy. In this case, up to 22% (41 GW) of the totally installed load in 2050 could be based on CCS. Assuming a more realistic scenario variant applying CCS to only 20 GW or lower would not be sufficient to reach the envisaged climate targets in the electricity sector. Furthermore, the growing public opposition against CO2 storage projects appears as a key barrier, supplemented by major uncertainties concerning the estimation of storage potentials, the long-term cost development as well as the environmental burdens which abound when applying a life-cycle approach. However, recently, alternative applications are being increasingly considered–that is the capture of CO2 at industrial point sources and biomass based energy production (electricity, heat and fuels) where assessment studies for exploring the potentials, limits and requirements for commercial use are missing so far. Globally, CCS at power plants might be an important climate protection technology: coal-consuming countries such as China and India are increasingly moving centre stage into the debate. Here, similar investigations on the development and the integration of both, CCS and renewable energies, into the individual energy system structures of such countries would be reasonable.
If the current energy policy priorities are retained, there may be no need to focus additionally on carbon capture and storage (CCS) in the power plant sector of Germany. This applies even in the case of ambitious climate protection targets, according to the results of the presented integrated assessment study. These cover a variety of aspects: Firstly, the technology is not expected to become available on a large scale in Germany before 2025. Secondly, if renewable energies and combined heat and power are expanded further and energy productivity is enhanced, there is likely to be only a limited demand for CCS power plants, as a scenario analysis of CCS deployment in Germany shows. Thirdly, cost analysis using the learning curve approach shows that the electricity generation costs of renewable electricity approach those of CCS power plants. This leads to the consequence that, from 2020, several renewable technologies may well be in a position to offer electricity at a cheaper rate than CCS power plants. In addition, a review of new life cycle assessments for CO2 separation in the power plant sector indicates that the greenhouse gas emissions from 1 kW h of electricity generated by first-generation CCS power plants could only be reduced by 68 % to 87 % (95 % in individual cases). Finally, a cautious, conservative estimate of the effective German CO2 storage capacity of approximately 5 billion tonnes of CO2 is calculated, including a fluctuation range yielding values between 4 and 15 billion tonnes of CO2. Therefore, the total CO2 emissions caused by large point sources in Germany could be stored for 12 years (basic value) or for 8 or 33 years (sensitivity values).
The main objective of this article is to evaluate CO2 mitigation potential and to calculate costs avoided by the use of different CO2 mitigation technologies in China's cement sector, namely energy efficiency improvements, use of alternative fuels, clinker substitution and carbon capture and storage (CCS). Three scenarios are designed based on the projection of cement output and technology development over the next 40 years (2010–2050). 2.5, 4.7 and 4.3 Gt tonnes of CO2 will be saved totally in basic scenario and two low carbon scenarios up to 2050. By comparing these technologies along the scenarios, it can be concluded that CO2 emissions can mainly be reduced by energy efficiency improvements and use of alternative fuels. Clinker substitution, which reduces the clinker-to-cement ratio as well as energy intensity, results in significant cost advantages. CCS, including post-combustion capture and oxy-fuel combustion capture, could play an important role in the capture of CO2 in the cement industry, and is expected to be in commercial use by 2030.
One of the factors decelerating a further diffusion of the carbon capture and storage (CCS) technology is the public's negative perception of early pilot or demonstration activities in Germany as well as in other countries. This study examined the public perception of CCS in more detail by looking into different options within the CCS chain, i.e. for the three elements capture, transport and storage. This was analyzed using an experimental approach, realized in an online survey with a representative German sample of 1830 citizens. Each participant evaluated one of 18 different CCS scenarios created using three types of CO2 source (industry, biomass, coal), two transport options (pipeline vs. no specification), and three storage possibilities (saline aquifer, depleted gas field, enhanced gas recovery (EGR)).
Overall, we found that the ratings of CCS were neutral on average. However, if the CO2 is produced by a biomass power plant or industry, CCS is rated more positively than in a scenario with a coal-fired power plant. The specifications of transport and storage interacted with each other such that scenarios including EGR or a depleted gas field without mentioning a pipeline were evaluated better than storing it in a saline aquifer or a depleted gas field and mentioning a pipeline as means of transport. Exploratory regression analyses indicate the high relevance of the respective CO2 source in general as well as the perceived importance of this source for Germany.
Prospects of carbon capture and storage (CCS) in India's power sector : an integrated assessment
(2014)
Objective: The aim of the present article is to conduct an integrated assessment in order to explore whether CCS could be a viable technological option for significantly reducing future CO2 emissions in India. Methods: In this paper, an integrated approach covering five assessment dimensions is chosen. However, each dimension is investigated using specific methods (graphical abstract).
Results: The most crucial precondition that must be met is a reliable storage capacity assessment based on site-specific geological data since only rough figures concerning the theoretical capacity exist at present. Our projection of different trends of coal-based power plant capacities up to 2050 ranges between 13 and 111 Gt of CO2 that may be captured from coal-fired power plants to be built by 2050. If very optimistic assumptions about the country's CO2 storage potential are applied, 75 Gt of CO2 could theoretically be stored as a result of matching these sources with suitable sinks. If a cautious approach is taken by considering the country's effective storage potential, only a fraction may potentially be sequestered. In practice, this potential will decrease further with the impact of technical, legal, economic and social acceptance factors. Further constraints may be the delayed commercial availability of CCS in India, a significant barrier to achieving the economic viability of CCS, an expected net maximum reduction rate of the power plant’s greenhouse gas emissions of 71-74%, an increase of most other environmental and social impacts, and a lack of governmental, industrial or societal CCS advocates.
Conclusion and practice implications: Several preconditions need to be fulfilled if CCS is to play a future role in reducing CO2 emissions in India, the most crucial one being to determine reliable storage capacity figures. In order to overcome these barriers, the industrialised world would need to make a stronger commitment in terms of CCS technology demonstration, cooperation and transfer to emerging economies like India. The integrated assessment might also be extended by a comparison with other low-carbon technology options to draw fully valid conclusions on the most suitable solution for a sustainable future energy supply in India.
Prospects of carbon capture and storage (CCS) in China's power sector : an integrated assessment
(2015)
Objective: The aim of the present article is to conduct an integrated assessment in order to explore whether CCS could be a viable technological option for significantly reducing future CO2 emissions in China. Methods: In this paper, an integrated approach covering five assessment dimensions is chosen. Each dimension is investigated using specific methods (graphical abstract). Results: The most crucial precondition that must be met is a reliable storage capacity assessment based on site-specific geological data. Our projection of different trends of coal-based power plant capacities up to 2050 ranges between 34 and 221 Gt of CO2 that may be captured from coal-fired power plants to be built by 2050. If very optimistic assumptions about the country’s CO2 storage potential are applied, 192 Gt of CO2 could theoretically be stored as a result of matching these sources with suitable sinks. If a cautious approach is taken, this figure falls to 29 Gt of CO2. In practice, this potential will decrease further with the impact of technical, legal, economic and social acceptance factors. Further constraints may be the delayed commercial availability of CCS in China; a significant barrier to achieving the economic viability of CCS due to a currently non-existing nation-wide CO2 pricing scheme that generates a sufficiently strong price signal; an expected life-cycle reduction rate of the power plant's greenhouse gas emissions of 59-60%; and an increase in most other negative environmental and social impacts. Conclusion and practice implications: Most experts expect a striking dominance of coal-fired power generation in the country's electricity sector, even if the recent trend towards a flattened deployment of coal capacity and reduced annual growth rates of coal-fired generation proves to be true in the future. In order to reduce fossil fuel-related CO2 emissions to a level that would be consistent with the long-term climate protection target of the international community to which China is increasingly committing itself, this option may require the introduction of CCS. However, a precondition for opting for CCS would be finding robust solutions to the constraints highlighted in this article. Furthermore, a comparison with other low-carbon technology options may be useful in drawing completely valid conclusions on the economic, ecological and social viability of CCS in a low-carbon policy environment. The assessment dimensions should be integrated into macro-economic optimisation models by combining qualitative with quantitative modelling, and the flexible operation of CCS power plants should be analysed in view of a possible role of CCS for balancing fluctuating renewable energies.
This article presents an integrated assessment conducted in order to explore whether carbon capture and storage (CCS) could be a viable technological option for significantly reducing future CO2 emissions in South Africa. The methodological approach covers a commercial availability analysis, an analysis of the long-term usable CO2 storage potential (based on storage capacity assessment, energy scenario analysis and source-sink matching), an economic and ecological assessment and a stakeholder analysis. The findings show, that a reliable storage capacity assessment is needed, since only rough figures concerning the effective capacity currently exist. Further constraints on the fast deployment of CCS may be the delayed commercial availability of CCS, significant barriers to increasing the economic viability of CCS, an expected net maximum reduction rate of the power plant's greenhouse gas emissions of 67%-72%, an increase in other environmental and social impacts, and low public awareness of CCS. One precondition for opting for CCS would be to find robust solutions to these constraints, taking into account that CCS could potentially conflict with other important policy objectives, such as affordable electricity rates to give the whole population access to electricity.
Facing the uncertainty of CO2 storage capacity in China by developing different storage scenarios
(2016)
China is very active in the research and development of CO2 capture and storage technologies (CCS). However, existing estimates for CO2 storage capacity are very uncertain. This uncertainty is due to limited geological knowledge, a lack of large-scale research on CO2 injection, and different assessment approaches and parameter settings. Hence storage scenarios represent a method that can be used by policy makers to demonstrate the range of possible storage capacity developments, to help interpret uncertain results and to identify the limitations of existing assessments. In this paper, three storage scenarios are developed for China by evaluating China-wide studies supplemented with more detailed site- and basin-specific assessments. It is estimated that the greatest storage potential can be found in deep saline aquifers. Oil and gas fields may also be used. Coal seams are only included in the highest storage scenario. In total, the scenarios presented demonstrate that China has an effective storage capacity of between 65 and 1551 Gt of CO2. Furthermore, the authors emphasise a need for action to harmonise storage capacity assessment approaches due to the uncertainties involved in the capacity assessments analysed in this study.