• Energy Research
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AbstractMaking new coal-fired power plants carbon capture ready (Carbon Capture Ready) in China has been recognised as a crucial by a number of stakeholders academics, energy companies and regional government, based on a study in EU-UK-China NZEC project. A number of publications have investigated the definition, engineering requirements, economic and finance of CCR for China. However there remain a number of questions regarding the extent to which a plant’s physical location might constrain the feasibility of CCS retrofit. To address this issue, a Geographical Information System (GIS) has been used as a tool for mapping current and planned large carbon dioxide sources in Guangdong, also illustrating potential storage sites and calculating possible carbon dioxide transportation route.This paper investigates the location factors that should be considered when locating new build CCR power plants and demonstrates the methodology of using GIS software with spatial analysis in planning new build power plant in Guangdong. A preliminary study has identified over 30 large power plants within the region, with plant locations and historical emission data collected and presented in ArcGIS. Factors such as distance to potential storage site, route of CO2 pipeline, extra space on site and potential development plan etc. were investigated in the modelling and calculated the potential source and sink solution. The study then moves on to suggest possible new build plant locations which can be easily fitted in to the current network, based on economic optimisation. The scope for future coal plant development combined with a possible nuclear plant siting plan is discussed towards the end of the paper.Guangdong province, which owns the third largest coal-fired power installed capacity out of 31 provinces, generated over 8% of China’s total electricity every year for the past 15 years. CO2 storage opportunities could be found in the surrounding South China Sea, where Guangdong has a total of 4,300 km of coastline and some small scale oil fields on shore within the region. It is also among the first places to start the national open and reform policy in China. The province is one of the richest in China, with the highest GDP among all other provinces since 1989, and the foreign trade accounts for more than a quarter of China’s total amount. It also contributes around 12 of the total national economic output. Currently, the provincial government is proposing a low carbon roadmap, which is the first of its kind in China.The work has created a totally new thinking on capture ready power plant planning. This differs from existing studies (e.g., which aim to investigate the existing carbon dioxide emission sources at specified location and provide source and sink matching analysis. Instead the study focuses on policy implementation for new build capture ready power plants. Three clusters within Guangdong province are identified as potential temporary CO2 storage hubs before transporting the gas to a long term storage site. When officials are planning new power plant locations from a capture ready perspective, the plants should not necessarily be close to storage sites in straight line, but rather should be within a reasonable distance of a cluster. Transport of the captured CO2 will not be limited to pipelines, but could be extended to road and rail tankers.Power plant parameters and storage site data were collected for this research. Public transportation, utilities, landscapes, river, land used and population data were referenced from various sources; therefore, some of the data could be out of date. Nevertheless, it should still provide enough information when deciding the location of the transport cluster. Any future work could build on the existing model with updated data. Moreover, it could fit in with the national natural gas transportation network and utility planning network to provide long term integrated energy system analysis.The paper could provide policy makers, investors and urban planning officials with a view on how conventional thermal power plant investment and planning could be optimised, using Carbon Capture Ready designs, to keep the CCS retrofitting option open.

AbstractChina has built at least 70 GW of new coal- fired power installed capacity annually since 2005 and the growth is expected to continue (CEC, 2008). Chinese government, industry and academic stakeholders perceive that China will not mandate new plants to be built with carbon dioxide capture and storage systems in the short term and there is little incentive even to contemplate the first steps needed to fit plants with capture equipment [Reiner, D., Liang, X., Sun, X., Zhu, Y., Li, D., 2007. Stakeholder attitudes towards carbon dioxide capture and storage technologies in China, International Climate Change Conference, Hong Kong, May 29–31 2007]. We investigate the value of making new plants CO2 Capture Ready (CCR), which would enable them to retrofit to capture CO2 without unnecessary additional costs when the appropriate policy and /or economic drivers are in place (IEA, 2007).In order to understand the value and investment characteristics of CCR in China, a typical 600 MW pulverized-coal -fired ultra-supercritical power plant, locating at Guangdong province, was examined. Combined with a detailed engineering assessment, we obtained the costs for different CCR scenarios. To analyze CCR investment opportunities, we apply a cash flow model for valuing Capture Options, as developed in [Liang, X., Reiner, D., Gibbins J., Li J., 2007. Fianncing CCR coal-fired power plants in China by issuing capture options, EPRG Working Paper Series, EPRG0728, Cambridge, December. Available at: www.electricitypolicy.org.uk/pubs/wp/eprg0728.pdf]. Results are obtained by Monte-Carlo simulation, based on engineering surveys and the IEA (2007) CCR study, as well as plant performance information and expert projections on carbon prices, coal prices and electricity prices.CCR investments are justified by factors such as higher retrofitting probabilities, lower early-closure probabilities and fair economic return. However, the economic case for CCR largely depends on the type of investments made, for example, CCR-essential investments tend to be more economic than additional non-essential CCR features such as CCR Essential with clutched low-pressure turbines. Carbon price, coal price and discount rate also were found to have significant impacts on the economics of CCR. Overall, it appears that the value of capture options are significant, and therefore clear retrofitting strategies would be valuable for any CCR investment.

Abstract The large-scale adoption of wood as a construction material for tall buildings could pave the way for sustainable construction. Its adoption, however, is hindered by a limited understanding of wood's behaviour in a fire. In particular, the effect of oxygen and heat flux on the burning (including pyrolysis) and ignition behaviour of wood is poorly understood. We addressed this gap by studying the effect of oxygen concentration and heat flux on the burning and ignition behaviour of particleboard experimentally and computationally. Particleboard was chosen as a proxy for all woody construction materials. We conducted over 60 experiments in an FPA on samples of particleboard spanning different oxygen concentrations (0–21%), heat fluxes (10–70 kW/m2), sample densities (600–800 kg/m2), and sample thicknesses (6–25 mm). Only the heat flux and oxygen concentration significantly affected the charring rate, time-to-flaming ignition, and burning mode (pyrolysis, smouldering, flaming). To explore this effect further, we used a multi-physics model of particleboard charring developed in Gpyro. Combining the computational and experimental results, we showed that particleboard undergoes only pyrolysis in oxygen concentrations below 4%, smouldering between 4 and 15%, and flaming above 15% at a heat flux of 30 kW/m2. These oxygen concentration thresholds were found to decrease as the heat flux increases. We also showed that smouldering and flaming increases the charring rate by 25 and 37%, respectively. This means that the rate of loss of a section of structural wood, quantified by the charring rate, in a fire due to smouldering is similar to that of flaming combustion. In addition, we noted the existence of a triple point for the ignition of wood at which a slight change in environmental conditions can lead to either smouldering, flaming, or only pyrolysis. In summary, this paper quantified for the first time the contributions of the three modes of burning to the charring rate of wood and highlights the importance of smouldering for timber construction.

AbstractPresented is an overview of the CO2QUEST project that addresses fundamentally important issues regarding the impact of typical impurities in the gas or dense phase CO2 stream captured from fossil fuel power plants on its safe and economic transportation and storage. Previous studies have mainly investigated the impact of CO2 stream impurities on each part of the carbon capture and storage (CCS) chain in isolation. This is a significant drawback given the different sensitivities of pipeline, wellbore materials and storage sites to the various impurities. The project brings together leading researchers and stakeholders, to address the impact of the typical impurities upon safe and economic CO2 transportation and storage. State-of-the-art mathematical models, backed by laboratory and industrial-scale experimentation, are implemented to perform a comprehensive techno-economic assessment of the impact of impurities upon the thermo-physical phenomena governing pipeline and storage-site integrities.

The ultimate composition of the CO2 stream captured from fossil fuel power plants or other CO2 intensive industries and transported to a storage site using high pressure pipelines will be governed by safety, environmental and economic considerations. So far, most of the studies performed on this topic have been limited in scope, primarily focusing on investigating the impact of the CO2 stream impurities on each part of the Carbon Capture and Sequestration (CCS) chain in isolation. This is a significant drawback given the markedly different sensitivities of the pipeline, well bore materials and storage sites to the various impurities. For example, given the risk of water table contamination, trace elements such as Lead, Mercury and Arsenic in the CO2 stream are of far greater concern in an aquifer storage site than compared to the pipeline. On the other hand, even small concentrations of water in the CO2 stream are detrimental to the pipeline due to corrosion, but of benefit even at high concentrations during storage given the immobilisation effect of water on CO2. 'What is good for the pipeline is not necessarily good for storage'. It is clear that the optimum composition and concentration of the impurities in the captured CO2 stream involves a delicate balance between the different requirements within the CCS chain, spanning capture, transportation and storage, with cost and safety implications being the over-arching factor. Pivotal to these considerations is an understanding of the impact of the impurities on the physico-chemical properties of CO2 and its hazard profile. This paper presents and overview of the current FP7 European Commission CO2QUEST project involving the collaboration of 12 industry and academic partners in Europe, China and Canada aimed at addressing fundamentally important and urgent issues regarding the impact of the typical CO2 streams impurities captured from fossil fuel power plants on its safe and economic transportation and storage. The work programme, spanning 36 months, focuses on the development of state-of-the-art mathematical models, backed, by laboratory and industrial-scale experimentation using unique EC-funded test facilities to perform a comprehensive techno-economic, risk-based assessment of the impact of the CO2 stream impurities on the phase behaviour and the physico-chemical reactions governing the pipeline and storage site integrities. The above involves the determination of the important CO2 mixtures that have the most profound impact upon the pipeline pressure drop, compressor power requirements, pipeline propensity to ductile and brittle facture propagation, corrosion of the pipeline and well bore materials, geochemical interactions within the well bore and storage site, and the ensuing health and environmental hazards. Based on a cost/benefit analysis and whole system approach, the results will in turn be used to provide recommendations for tolerance levels, mixing protocols and control measures for pipeline networks and storage infrastructure thus contributing to the development of relevant standards for the safe design and operation of CCS. Acknowledgement: The CO2QUEST project has received funding from the European Union 7th Framework Programme FP7-ENERGY-2012-1-2STAGE under grant agreement number 309102.

AbstractA consensus for the development of a low carbon economy in China is growing rapidly among Chinese energy stakeholders. But there is considerable uncertainty as to the role that carbon capture and storage (CCS) retrofit could play in this development. The State Council in China has set a target of cutting carbon dioxide emissions per unit of GDP by 40% by 2020 compared with the level for 2005. Although this provides some policy impetus for reducing carbon dioxide emissions in China, it is also important to note that over 350 GW of coal-fired power plant capacity has been built within the past five years and that these power plants are expected to operate for at least another 25 years. Because coal is an affordable and accessible fuel in China, both the China Electricity Council (CEC) and the International Energy Agency (IEA) estimates that another 300 GW of supercritical and ultra-supercritical new coalfired power plants will be constructed in the next decade to satisfy the growing energy demand of the country .But unless other options to reduce emissions can be implemented, a simple consideration of the emissions they produce suggests that some of these recently built power plants may be required to shut down within the next two decades to address Chinese and/or international climate policies. During the past five years, the national policy of ‘closing smaller and/or inefficient units to build large and more efficient units’ has been implemented not only to save energy, but also to reduce specific carbon dioxide emissions (i.e. reduced gCO2/kWh of electricity produced). Forcing early plant closure has, however, proved to be a difficult task under the institutional framework of the Chinese electricity sector, because these plants usually had not reached the end of their design lifetimes. Also it was only partially successful in the context of CO2 reduction in the sense that companies wanted to build large plants to increase electrical output and strict rules meant they could only do this by closing a specified amount of older plant. But the end result was still that more coal was burnt and hence total CO2 emissions to atmosphere increased. Retrofitting some of the existing power plants to capture CO2, which by contrast can achieve an absolute decrease in CO2 emissions to atmosphere for an analogous loss in plant output (to the closures previously enforced) is therefore, an important option to address the threat of climate change while maintaining in the meantime the country’s electricity supply from coal.A preliminary investigation of over 100 large power plants in China was conducted to determine their potential for a retrofit with CO2 capture, transport and storage. Factors assessed included geographic location, space on site, plant layout, water restriction, coal supply, efficiency, FGD status and potential access to storage sites. Based on these criteria, retrofitting prospects were evaluated and rated. It appears that about 45% of existing power plants may suffer from ‘carbon lock-in’ status, i.e. their emissions could not be abated using CCS technology, at least at ‘reasonable’ cost. Critical factors that would preclude capture retrofit are, not surprisingly, access to storage sites and unsuitable plant layout and/or space on site. Variations in other factors would affect the level of retrofitting cost, but this effect could be positive as well as negative. In principle, plants would be retrofitted in an order that reflects the extent to which these site specific factors would give higher or lower retrofit costs.The results aim to provide an overview of the potential issues that need to be considered by stakeholders, policy makers and manufacturing companies when deciding the market potential for CCS retrofit technology in China.

A crucial element of the quest of curbing carbon dioxide emissions is deemed to rely on a biobased economy, which will rely on the development of financially sustainable biorefining systems enabling a full exploitation of lignocellulosic biomass (and its macrocomponents such as cellulose, hemicellulose, and lignin) for the coproduction of biofuels and bioderived platform chemicals. In this work, a general modeling framework conceived to steer decision-making regarding the strategic design and systematic planning of advanced biorefining supply networks is presented. The design task is formulated as a mixed integer linear program which accounts for the maximization of the supply chain profit, considering multiechelon, multiperiod, multifeedstock, and multiproduct aspects as well as spatially explicit features. The applicability of the proposed model, along with the use of a bilevel decomposition approach, are demonstrated with a case study of lignocellulose-based biorefining production systems in the South-...