Greenhouse gas emissions in China 2007: Inventory and input–output analysis

For greenhouse gas (GHG) emissions by the Chinese economy in 2007 with the most recent statistics availability, a concrete inventory covering CO₂, CH₄, and N₂O is composed and associated with an input–output analysis to reveal the emission embodiment in final consumption and international trade. The estimated total direct GHG emission amounts to 7456.12 Mt CO₂-eq by the commonly referred IPCC global warming potentials, with 63.39% from energy-related CO₂, 22.31% from non-energy-related CO₂, 11.15% from CH₄ and 3.15% from N₂O. Responsible for 81.32% of the total GHG emissions are the five sectors of the Electric Power/Steam and Hot Water Production and Supply, Smelting and Pressing of Ferrous and Nonferrous Metals, Nonmetal Mineral Products, Agriculture, and Coal Mining and Dressing, with distinctive emission structures. The sector of Construction holds the top GHG emissions embodied in both domestic production and consumption, and the emission embodied in gross capital formation is prominently more than those in other components of the final consumption characterized by extensive investment in contrast to limited household consumption. China is a net exporter of embodied GHG emissions, with emissions embodied in exports of 3060.18 Mt CO₂-eq, in magnitude up to 41.04% of the total direct emission.     

The embodied energy and environmental emissions of construction projects in China: An economic input–output LCA model

A complete understanding of the resource consumption, embodied energy, and environmental emissions of civil projects in China is difficult due to the lack of comprehensive national statistics. To quantitatively assess the energy and environmental impacts of civil construction at a macro-level, this study developed a 24 sector environmental input–output life-cycle assessment model (I–O LCA) based on 2002 Chinese national economic and environmental data. The model generates an economy-wide inventory of energy use and environmental emissions. Estimates based on the level of economic activity related to planned future civil works in 2015 are made. Results indicate that the embodied energy of construction projects accounts for nearly one-sixth of the total economy's energy consumption in 2007, and may account for approximately one-fifth of the total energy use by 2015. This energy consumption is dominated by coal and oil consumptions. Energy-related emissions are the main polluters of the country's atmosphere and environment. If the industry's energy use and manufacturing techniques remain the same as in 2002, challenges to the goals for total energy consumption in China will appear in the next decade. Thus, effective implementation of efficient energy technologies and regulations are indispensable for achieving China's energy and environmental quality goals.     

On the optimal selection of wall cladding system to reduce direct and indirect CO2 emissions

Buildings have direct and indirect impacts on the CO₂ emissions. This paper presents a study on the impact of wall systems and cladding materials on the CO₂ emissions and aims to analyse the performance of those systems in order to provide designers with reliable technical data. The studied systems include stucco, masonry veneer, aluminium siding, vinyl siding and the exterior insulation and finish systems (EIFS). To evaluate the economic performance, environmental performance and embodied energy, green building modelling system was used, while to estimate the impact of operational energy, a simulation model was first used and then simple bottom-up model constructed. A sensitivity analysis was conducted in order to determine the relative influence of each system on a representative educational building. It was found that some cladding materials reduce the direct CO₂ emissions, but provide a moderate reduction in terms of operational energy, and vice versa. Others positively impact the embodied energy and environmental performance and can optimise the operational energy performance. Therefore, a careful evaluation should be carried out in selecting wall cladding systems and finishing materials in order to reduce the CO₂ emissions effectively.     

Potential impact of (CET) carbon emissions trading on China’s power sector: A perspective from different allowance allocation options

In Copenhagen climate conference China government promised that China would cut down carbon intensity 40–45% from 2005 by 2020. CET (carbon emissions trading) is an effective tool to reduce emissions. But because CET is not fully implemented in China up to now, how to design it and its potential impact are unknown to us. This paper studies the potential impact of introduction of CET on China’s power sector and discusses the impact of different allocation options of allowances. Agent-based modeling is one appealing new methodology that has the potential to overcome some shortcomings of traditional methods. We establish an agent-based model, CETICEM (CET Introduced China Electricity Market), of introduction of CET to China. In CETICEM, six types of agents and two markets are modeled. We find that: (1) CET internalizes environment cost; increases the average electricity price by 12%; and transfers carbon price volatility to the electricity market, increasing electricity price volatility by 4%. (2) CET influences the relative cost of different power generation technologies through the carbon price, significantly increasing the proportion of environmentally friendly technologies; expensive solar power generation in particular develops significantly, with final proportion increasing by 14%. (3) Emission-based allocation brings about both higher electricity and carbon prices than by output-based allocation which encourages producers to be environmentally friendly. Therefore, output-based allocation would be more conducive to reducing emissions in the Chinese power sector.     

Experimental study of inlet manifold water injection on combustion and emissions of an automotive direct injection Diesel engine

This paper describes an experimental study conducted on a modern high speed common-rail automotive Diesel engine in order to evaluate the effects on combustion and pollutant emissions of water injected as a fine mist in the inlet manifold.     

Emissions impacts of plug-in hybrid electric vehicle deployment on the U.S. western grid

The constantly evolving western grid of the United States is characterized by complex generation dispatch based on economics, contractual agreements, and regulations. The future electrification of transportation via plug-in electric vehicles calls for an energy and emissions analysis of electric vehicle (EV) penetration scenarios based on realistic resource dispatch. A resource dispatch and emissions model for the western grid is developed and a baseline case is modeled. Results are compared with recorded data to validate the model and provide confidence in the analysis of EV-grid interaction outlooks. A modeled dispatch approach, based on a correlation between actual historical dispatch and system load data, is exercised to show the impacts (emission intensity, temporally resolved load demand) associated with EV penetration on the western grid. The plug-in hybrid electric vehicle (PHEV) and selected charging scenarios are the focus for the analysis. The results reveal that (1) a correlation between system load and resource group capacity factor can be utilized in dispatch modeling, (2) the hourly emissions intensity of the grid depends upon PHEV fleet charge scenario, (3) emissions can be reduced for some species depending on the PHEV fleet charge scenario, and (4) the hourly model resolution of changes in grid emissions intensity can be used to decide on preferred fleet-wide charge profiles.     

生物柴油醛、酮类污染物的排放特性与分析

采用2,4-二硝基苯肼(DNPH)衍生法和高效液相色谱(HPLC)技术,对柴油机排气中的醛、酮污染物进行了捕集和分离测定,考察了柴油机燃用BD100、BD50、BD0时,不同负荷下的醛、酮污染物排放规律,分析了燃料组分、缸内温度、压力、排气温度等对醛、酮污染物排放的影响。研究结果表明,该方法可实现微量醛、酮污染物的准确、快速测定;柴油机排气中含量较高的羰基物有甲醛、丙醛、丙烯醛、乙醛、丙酮、丁酮和丁醛,其排放水平均随负荷增大而呈下降的趋势;高负荷时,高温区域的滞留时间延长,醛、酮类被再次氧化、转化几率增加;较高的排气温度会促使排气中的醛、酮类物质和HC燃料再次氧化生成CO和CO2。     

Scenario analysis of China’s emissions pathways in the 21st century for low carbon transition

China’s growing demand for energy – and its dependence on coal – has seen its carbon emissions increase more than 50% since 2000. Within the debate about mitigating global climate change, there is mounting pressure for emerging economies like China to take more responsibility for reducing their carbon emissions within a post-2012 international climate change policy framework. For China, this leads to fundamental questions about how feasible it is for the country to shift away from its recent carbon intensive pattern of growth. This paper presents some general results of scenarios that have been developed to investigate how China might continue to develop within a cumulative carbon emissions budget. The results show how changes in the key sectors of the Chinese economy could enable China to follow four different low carbon development pathways, each of which complies with a cumulative emissions constraint. Each scenario reflects different priorities for governmental decision making, infrastructure investments and social preferences. Having compared the key features of each scenario, the paper concludes with some implications for Chinese government policy.     

A model for the development of a power production system in Greece,Part I: Where RES do not meet EU targets

This paper studies the electricity production system of the Greek Interconnected Electric Production System using a model created with the software package WASP-IV. The period of study is from 2009 to 2030. It consists of three scenarios using three different criteria: energy, environmental and economic. The three scenarios are the business as usual, the lignite and the natural gas. Subsequently, a sensitivity analysis is carried out for the annual growth rate of electricity consumption and load demand. The paper examines how the three criteria change, when there are no other energy sources beyond those already in use (lignite, oil, natural gas, biomass, solar, wind and hydropower) with no CO₂ capture policies and with the electricity production from Renewable Energy Sources not to reach the targets of the European Union for 2020. In a second paper, three other scenarios examine production with the Renewable Energy Sources to reach the targets of the European Union for 2020.     

Partial substitution of hydrogen for conventional fuel in an aircraft by utilizing unused cargo compartment space

Options are being actively sought in aviation to switch from petroleum-based fuels to alternative fuels, of which hydrogen is a promising candidate, despite challenges associated with its production and storage. The possibility is demonstrated in this study of using hydrogen in place of some mission fuel without making substantial aircraft modifications and while utilizing only available unused baggage space in the lower-deck cargo compartments of aircraft. The environmental impact reduction and weight increase are obtained accounting for a broad range of factors including aircraft model, seat capacity, passenger and baggage load factors, annual landing and take off cycles, container type, and costs of metal hydride and gaseous hydrogen storage units of various sizes. It is found that, while there may be a cost increase, CO₂ emissions are substantially reduced, by 25,000–570,000 tonnes annually in several cases and by up to 1.1 million tonnes annually for the 10 types of aircraft considered. It is also determined that with present technology, despite the low density of hydrogen, the weight of storage systems constitutes more of a challenge than their volume in aviation. Large-body aircraft are found to have more difficulties than the narrow-body aircraft regarding storage system weight. For the most frequently used narrow- and large-body aircraft considered, the number of the available containers within the required limits of weight and volume respectively are found to be 3 and 4 for the B 737-800 aircraft and 2 and 10 for the A 340-300 aircraft. Overall, the combined usage of hydrogen and kerosene investigated here may be feasible in the future, but is a challenging option with present technology and aircraft due to various factors.