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Abstract: Concentrating solar thermal (CST) technology has been commercially proven in utility-scale power plants that have been in operation since the 1980’s. CST uses reflecting surfaces to focus solar energy onto collectors, generating extreme heat than can be used for a variety of purposes. The current focus of CST is large-scale electrical power generation. However, new applications, such as solar fuels, are quickly gaining momentum. One key shortcoming of CST technology is its sensitivity to disruptions in sunlight availability over time. CST systems require either thermal energy storage or backup systems to operate during heavy cloud periods or at night. On the other hand, fossil-based energy systems have high availability and reliability, but they generate substantial CO2 emissions compared to equivalent CST processes. A novel solution would combine the benefits of CST technology and of fossil-fueled energy systems. Such a solar-fossil hybrid system would guarantee energy availability in the absence of sunlight or stored solar energy. The addition of carbon capture to these systems could reduce their carbon intensity to almost zero. This paper introduces three important solar-fossil hybrid energy systems: (1) Integrated Solar Combined Cycle (ISCC), (2) Solar-assisted post-combustion capture (SAPCAP), and (3) Solar gasification with CO2 capture. These novel concepts have great potential to overcome the inherent limitations of their component technologies and to achieve superior greenhouse gas mitigation techno-economic performance in large-scale applications. The paper describes the features of the three solar-fossil hybrid systems described earlier, discusses its advantages and disadvantages, and provides examples of applications. The goal of this manuscript is to introduce experts in the CCS and CST fields to the opportunities of integration between these technologies and their potential benefits. [Copyright &y& Elsevier]

Abstract: The Dutch Ministry of Spatial Planning and the Environment (VROM) engaged Jacobs Consultancy to develop a definition and measuring tool aimed at quantifying the CO2 Capture Readiness of a combustion plant. The tool developed tests the level and completeness of pre-project execution information. The testing of pre-project information is a standard practice in the refining and petrochemical industry and Jacobs Consultancy has adapted and tailored these practices to develop the Capture Readiness tool. The tool was developed in 2008 and was pilot tested on two already permitted coal fired power plant projects in 2009. The Capture Readiness tool is similar in concept to the well known Project Definition Rating Index originally introduced by the Construction Industry Institute for Major Capital Projects. The tool quantifies the readiness of a project to accommodate future CO2 capture and parallels the phased approached to Major Capital Projects used by the Project Definition Rating Index. A short introduction to the application of the PDRI methodology to test the completeness of the project development information–often also referred to as Front End Loading or FEL, is included in this paper to establish the parallel approach we have used in the development of the Capture Readiness tool. The Jacobs Consultancy Capture Readiness tool is then discussed in more detail. [Copyright &y& Elsevier]

Abstract: This paper presents an environmental assessment of three scenarios postulating a national deployment of the Carbon Capture and Storage (CCS) chain by 2020–2050 on the French biggest industrial CO2 emitters (41 emitters among 9 industrial sectors) that had been carried out as part of the SOCECO2 project. 1 [1] SOCECO2 project, funded by the French National Research Agency, 2006–2009, involving the following partners: ALSTOM Power, APESA, BRGM, CNRS-CIRED, GDF Suez, IFP Energies nouvelles, INERIS, TOTAL. This analysis is based on the comparison of these CCS scenarios with reference scenarios without CCS at the same timeframe. Results detailed below focus on greenhouse gas (GHG) emissions and energy consumption, although NOx and SOx emissions balances have also been evaluated in the same project. Conclusions of this study provide information about the extent and main contributing factors of potential environmental outcomes (negative or positive) associated to CCS deployment. [Copyright &y& Elsevier]

Abstract: The capture and sequestration of CO2 will be necessary to mitigate CO2 emissions from fossil fuel (coal, oil, natural gas or biomass) power generation facilities in a carbon constrained world. Post combustion carbon capture is a viable technology alternative to reduce CO2 emissions from power plants in the short term. The CO2 concentration in the exhaust gases of natural fired power plants can be increased through exhaust gas recirculation (EGR). A joint CO2 Capture Project (CCP) and GE study of the Best Integrated Technology (BIT) shows that EGR enables reduced exhaust gas flow to the post combustion capture plant and cost of the CO2 capture. This paper describes the experimental work performed at General Electric Global Research Center in order to better understand the risks of utilizing EGR in combination with dry low NO x (DLN) combustors. A research combustor was developed for exploring the dry low emissions capability of nozzles to operate in low O2 environment. A series of experiments have been conducted at representative gas turbine pressures and temperatures, in an EGR test rig. Exhaust gas generated in a first stage, at pressure, is used to vitiate the fresh air to levels determined by cycle models. Experimental results include the effect of applying EGR on operability, efficiency and emissions performance under conditions of up to 30% EGR (low oxygen). Our findings confirm the feasibility of EGR for enhanced CO2 capture, exceeding the expectations of operability and combustion efficiency predicted by models. In addition, we confirm benefits of NO x reduction while complying with CO emissions in Dry Low NO x Emissions combustors under low oxygen content oxidizer. [Copyright &y& Elsevier]

Abstract: Due to its compatibility with the current energy infrastructures and the potential to reduce CO2 emissions significantly, CO2 capture and geological storage is recognised as one of the main options in the portfolio of greenhouse gas (GHG) mitigation technologies being developed worldwide. The CO2 capture technologies offer a number of alternatives, which involve different energy consumption rates and subsequent environmental impacts. Life cycle assessment (LCA) not only tracks energy and non-energy related GHG releases but also tracks various other environmental releases, such as solid wastes, toxic substances and common air pollutants, as well as the consumption of other resources, such water, minerals and land use. This paper presents the principles of the LCA model developed at Imperial College and uses the post combustion capture example to demonstrate the methodology in detail. [Copyright &y& Elsevier]

Abstract: There exists within the electricity generation sub-sector the potential for substantial GHG reductions through the application of CO2 capture and storage technologies. Many assessments of the cost and performance of power plants with CCS (Carbon Capture and Storage) have been undertaken but these studies almost always omit considering operability: the ability of a process to operate satisfactorily under conditions different than the nominal design conditions. Electricity systems rely upon generators with a high degree of operability in order to meet variations in power demand, ambient conditions, fuel supply, etc. and the need for operability is expected to increase in the future. The operability of CCS technologies could have a major impact on the extent to which CCS is used in the years to come and it could also affect the choice of the optimum CO2 capture technology. The attention given to the operability of power plants with CCS is in sharp contrast to its potential significance; only a handful of the research groups contributing to the sizeable CCS literature are explicitly investigating the operability of these technologies. This paper seeks to correct this oversight and proposes the scope of a comprehensive comprehensive assessment of the leading CO2 capture schemes—pre-combustion, post-combustion, and oxy-combustion— with respect to operability. In the final analysis, a layered approach is suggested with four major study areas: [•] flexibility [•] controllability [•] start-up/shutdown characteristics [•] assessment of trade-offs between operability and cost While the proposed undertaking is ambitious, it is believed that by building upon the existing process modelling and simulation expertise that exists with the CCS community, the work could be completed within a reasonable amount of time. [Copyright &y& Elsevier]

Abstract: Post-combustion capture of CO2 is a key technology for the reduction of greenhouse gas emissions from Australian coal fired power stations. It is an emerging technology, which still faces significant challenges in scaling up to full commercial scale suitable for power station applications. To increase adoption by the power industry significant cost reductions in capital and operating cost must be realised. CSIRO has developed an integrated post-combustion capture R&D and pilot plant program aimed at bringing down the barriers for commercial deployment. This paper provides an overview of the program and its status. [Copyright &y& Elsevier]

Abstract: The effect of the increasing concentration of CO2 in the atmosphere on climate change is a major driving force for the development of advanced energy cycles incorporating CO2 management options. Growing interest in the technical and economic feasibility of CO2 capture from large coal-based power plants has led to increased efforts worldwide to develop new concepts for greater CO2 reductions in the future. Greenhouse gas emissions, especially CO2, have to be reduced by 50–80% by 2050, according to the IPCC . The type of fuel used in cement manufacture directly impacts on CO2 emissions, with coal accounting for around 60–70% of CO2 emissions from cement installations. Therefore, the large amount of carbon dioxide emitted during cement manufacturing process - 5% of the total emissions of CO2 from stationary sources worldwide - is a cause of great concern and has to be tack led in order to comply with current legislation. Several technologies are available and have been proposed for the separation of CO2 from the flue gases from new and existing plants with retrofit capture units. Few studies have been undertaken on CO2 capture in cement plants to assess the suitable technologies, with oxy-combustion and amine scrubbing as the possible options (pre-combustion capture not being viable). This paper summarises the different CO2 capture technologies suitable for cement industry and assesses the potential of the calcium looping cycle as a new route for CO2 capture in the cement industry. The potential advantage of this system is the very low efficiency penalty expected (<6%) compared with other capture technologies as the heat required for calcination is balanced by heat released during the carbonation (CO2 capture) step and can be utilized efficiently at high temperature in the plant’s steam cycle. Since limestone is already used for cement manufacture, and because it is a cheap material with good geographical distribution, it allows the use of local limestone resources with minimal limestone-related infrastructure investment. Another envisaged benefit of this new technology is that the lime purged from the cycle could be us ed as a raw material for the production of cement clinker. Therefore, the calcium looping cycle can potentially have an important impact in reducing CO2 emissions from the cement industry, and may also be applicable in other sectors. [Copyright &y& Elsevier]