Comparison of Embodied Energy/CO_(2)of Office Buildings in China and Japan

The embodied energy/CO2 of buildings in China and Japan, which reflects the characteristic industrial efficiency ofbui｜ding materials, is described in this paper. The energy consumption and CO2 intensities for the dominant materials used in buildings are derived from the energy consumption in factories, and the energy consumption to produce equipment is derived from IO （input/output） analysis in order to compare the embodied energy/CO2 for buildings between China and Japan based on the same estimation method. Although the energy consumption of structures in China is two to three times greater than in Japan, the interior finish and air conditioning equipment, for example, are simpler and smaller. As a result, the embodied energy/CO2 of office buildings in China is only 10% to 20% greater than that of Japanese office buildings. Thus, the embodied energy/CO2 of buildings depends on both industrial efficiencies and building design trends of the country.

Evaluating the LCA of a Building with Close Embodied Energy Which Has Different Functions

Annual energy consumption and annual Global Warming Potential （GWP） decreases with the improving of the energy performance of the facade, whereas the embodied energy and embodied GWP increases due to the extra material and products applied. This study analyses the relation between the embodied energy and the energy consumption of a house during the life span of the buildings, and the results represented separately in tables and figures. The study uses Life Cycle Assessment （LCA） framework as a tool to conduct a partial LCA, from cradle to site of the construction and energy consumption during usage phase of the buildings with three different wall types through 50 years usage phase. According to this study, laminated timber and aerated concrete are better choices than cast concrete for both types of buildings because of lower density and lower U value.

Evaluation of Embodied Energy and Construction Costs for the Design of Low-Rise Apartments for Low-Income Residents in Surabaya, Indonesia

Low-rise apartments for low-income residents have been built in Surabaya in recent years. They have four stories and many rooms, and the dwellers are all small traders. Because these projects are built with funds from the government, the buildings are designed to consider the cost of construction, without consideration of embodied energy material. As a result, the buildings are not optimal in terms of embodied energy and construction cost. At present, because there are both concerns over global warning and a worldwide energy crisis, the embodied energy in a building is a very important concept for building design, because it can determine usage of energy in relation to natural sources, especially fossil fuels. This is part of the sustainable design concept. This paper describes research regarding： differences in embodied energy and construction cost between different wall materials, including brick, corn block and lightweight concrete in low rise apartments; the optimal relationship between embodied energy and building cost; and which factors determine these differences. The findings of this research show that lightweight concrete is the best material for the building walls; apartments for low-income in Surabaya still do not represent optimal construction design; and that sustainable buildings are cheaper than those that do not use this concept.

Study on Impact of Embodied Energy and CO2 Emissions for Prolongation of Building Life Time： Case Study in Japan

In this study, we looked at a method quantifying EEC （embodied energy and CO2） and the effect when we prolonged the building life time particularly through the durable improvement of the structure. Increasing the covering thickness of concrete for reinforcing bars and the earthquake-resistant strength are methods to increase the durability of the structure. The calculation method to obtain the quantity of concrete and reinforcing bars is provided. The EEC increase is evaluated from the 2005 input-output table in Japan. These results show that EE （embodied energy） in the construction phase is increased by 11% to 20% and EC （embodied CO2） 17% to 32%. However, annual EE is reduced 66% to 72% and EC 70% to 79%,

Embodied Energy and CO2 Associated with Buildings by Using Input and Output Table in Japan

In July 2009, the 2005 basic Japanese input/output table was publicized together with its physical transaction table. This research paper analyzed the 2005 IO （input/output） table to create building industry-related intensities and, at the same time, compared the building industry with industries at large for distribution margins and transportation. The analysis of distribution margins separately for middle and purchaser margins found that middle margins in the building industry are minor at 35% of the averages for all industries, while purchaser margins are sizable at 1.8 times, proving that it is an industry for which local production for local consumption is quite effective. CO2 emissions resulting from transportation in the building industry were calculated and concisely characterized. Although the ratio of transportation CO2 emissions to total CO2 emissions in each industry finds almost no difference between general industries and the building industry, transportation CO2 emissions per production value are two to three times heavier than those from general industries to be justified as a transportation-intensive industry.

Intensity Calculation Using Input-Output Table and Case Study Regarding Embodied Energy/CO2 in Japan

The objective of this research is to quantify the EEC （embodied energy/CO2） of a building. The EEC represents the energy consumption and CO2 emissions at individual phases of a building＇s life-cycle, such as construction （including manufacture of materials and equipment）, renewal （including repair work） and demolition. Energy and CO2 emission intensities in terms of 401 sectors were calculated, using the 2005 I-O （input-output） table in Japan. According to our case study conducted from the construction phase to demolition, the EC （embodied CO2） of an office building used for 60 years is 12,044 t-CO2 and 1,093 kg-CO2/m^2 in total. CO2 equivalent emissions （CO2e） by Freon gases, contained in building materials, equipment and devices, were also calculated. As the results, CO2e by insulators was 2% of the building＇s EC and CO2e by refrigerants was 9%-12% of the building＇s EC. It is important to keep reducing emissions of Freon gases contained in refrigerators.

Impact of Different Parameters on Life Cycle Analysis, Embodied Energy and Environmental Emissions for Wind Turbine System

Due to the rapid depletion of fossil fuel reserves and increasing concern for climate change as a result of greenhouse gas effect, every country is looking for ways to develop eco-friendly renewable energy sources. Wind energy has become a good option due to its comparative economic advantages and environment friendly aspects. But there is always an ongoing debate if wind energy is as green as it seems to appear. Wind turbines once installed do not produce any greenhouse gases during operation, but it can and may produce significant emissions during manufacture, transport, installation and disposal stages. To determine the exact amount of emissions, it is necessary to consider all the stages for a wind turbine from manufacture to disposal. Life Cycle Analysis (LCA) is a technique that determines the energy consumption, emission of greenhouse gases and other environmental impacts of a product or system throughout the life cycle stages. The various approaches that have been used in the literature for the LCA of wind turbines have many discrepancies among the results, the main reason(s) being different investigators used different parameters and boundary conditions, and thus comparisons are difficult. In this paper, the influence of different parameters such as turbine size, technology (geared or gearbox less), recycling, medium of transport, different locations, orientation of the blade (horizontal or vertical), blade material, positioning of wind turbine (land, coastal or offshore), etc. on greenhouse gas emissions and embodied energy is studied using the available data from exhaustive search of literature. This provides tools to find better solutions for power production in an environmental friendly manner by selecting a proper blade orientation technique, with suitable blade material, technology, recycling techniques and suitable location.

Embodied energy consumption and carbon emissions evaluation for urban industrial structure optimization

Cities are the main material processors asso- ciated with industrialization. The development of urban production based on fossil fuels is the major contributor to the rise of greenhouse gas density, and to global warming. The concept of urban industrial structure optimization is considered to be a solution to urban sustainable develop- ment and global climate issues. Enforcing energy con- servation and reducing carbon emissions are playing key roles in addressing these issues. As such, quantitative accounting and the evaluation of energy consumption and corresponding carbon emissions, which are by-products of urban production, are critical, in order to discover potential opportunities to save energy and to reduce emissions. Conventional evaluation indicators, such as ＂energy consumption per unit output value＂ and ＂emissions per unit output value＂, are concerned with immediate consumptions and emissions; while the indirect consump- tions and emissions that occur throughout the supply chain are ignored. This does not support the optimization of the overall urban industrial system. To present a systematic evaluation framework for cities, this study constructs new evaluation indicators, based on the concepts of ＂embodied energy＂ and ＂embodied carbon emissions＂, which take both the immediate and indirect effects of energy consumption and emissions into account. Taking Beijing as a case, conventional evaluation indicators are compared with the newly constructed ones. Results show that the energy consumption and emissions of urban industries are represented better by the new indicators than by conventional indicators, and provide useful information for urban industrial structure optimization.

Energy Embodied in Goods in International Trade of China: Calculation and Policy Implications

In recent years, China's energy demand and Greenhouse gas (GHG) emissions have grown very fast, quite an amount of which was exported as energy embodied in goods in international trade rather than consumed domestically. Starting from the concept of embodied energy, based on input-output energy analysis approach, in this paper the energy embodied in goods in international trade of China during the period from 2001 to 2006 is calculated. The results show that although China has become a net importer of petroleum since 1993, China is a net exporter of embodied energy due to international trade in goods. In 2002, the total amount of energy embodied in exported goods was about 410 million tce (ton of coal equivalent, hereinafter referred to as "tce"). Eliminating the amount of energy embodied in imported goods of about 170 million tce, the net export of embodied energy was about 240 million tce, accounting for 16% of the aggregate primary energy consumption of that very year in China, and the net export of embodied emissions was about 150 million tons of carbon. With the rapid growth of China's international trade, assuming no structural input-output changes of among sectors, in 2006 the net export of embodied energy went up to about 630 million tce, an increase of 162 % over 2002. In addition, this paper also analyzes the possible sources of error in calculation, and also discusses the policy implications according to the result of the calculation.

Embodied coefficient of energy carriers and its calculation method

To quantify the energy consumption in the process of production, transportation and processing of energy carriers, the life cycle of building energy used can be divided into two phases： on-site phase and embodied phase. As for the embodied phase, with the data in existing statistic yearbook, the consumption items of energy production and transportation were investigated. And based on the life cycle theory, an embodied coefficient of energy carriers was proposed to quantify the embodied energy consumption. Moreover, a calculation method for the embodied coefficient of energy carriers was deduced using Leontief inverse matrix based on the existing data sources. With relevant data of 2005-2007 in China, the embodied coefficients in 2005-2007 were obtained, in which the values for natural gas and thermal power are around 1.3 and 3. l, respectively; while they are 1.03-1.08 for other selected energy carriers. In addition, it is also found that the consumption in the production and processing accounts for more than 75%.

Analysis of the Energy Embodied in Foreign Goods Trade of China

In recent years,scientists have been increasingly interested in the energy embodied in traded goods among countries.In this article,the direct energy intensities in various economic sectors of China were calculated with the data of energy consumption and output value of each sector,and the input-output table was used to estimate the external energy consumption.The total energy intensity of all sectors was then obtained.From the data of international trade,the energy embodied in goods trade of China was estimated for the period of 1994-2001.During this period,the average energy intensity of imported goods was always higher than that of exported ones.As a country with a surplus in international goods trade,China actually imported net embodied energy in the past few years.The net embodied energy imported was at the same magnitude of the imported energy in the form of fossil fuels.

A process-level hierarchical structural decomposition analysis (SDA) of energy consumption in an integrated steel plant

A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2011-2013. By combining the principle of hierarchical decomposition into D&L method, a hierarchical decomposition model for multilevel SDA is obtained. The developed hierarchical IO-SDA model would provide consistent results and need less computation effort compared with the traditional SDA model. The decomposition results of the steel plant suggest that the technology improvement and reduced steel final demand are two major reasons for declined total energy consumption. The technical improvements of blast furnaces, basic oxygen furnaces, the power plant and the by-products utilization level have contributed mostly in reducing energy consumption. A major retrofit of ancillary process units and solving fuel substitution problem in the sinter plant and blast furnace are important for further energy saving. Besides the empirical results, this work also discussed that why and how hierarchical SDA can be applied in a process-level decomposition analysis of aggregated indicators.

China’s Export Expansion, Export Structure and Energy Consumption

Since the reform and opening up,China's export trade has maintained a rapid growth;meanwhile,China's energy consumption has been increasing sharply. "High export and high energy consumption" has become the feature of China's trade and economic development.In this paper,based on the input-output analysis approach,the authors have conducted an empirical study on the export trade and energy consumption of 21 trade industrial sectors.The results show that,China is a big net exporter of embodied energy.Assuming that the export growth rate of embodied energy maintains to be about 23.6%,the average annual growth rate of the past 32 years,and based on the input-output data of 2005,by 2030 China's net export of embodied energy would be over eight times more than the aggregate energy production,which is obviously infeasible.As a country of very low per capita energy,China must change its export pattern,encourage or restrain the export of different industrial sectors according to their energy consumption intensity,and promote structural change of energy-efficient exported products,so as to achieve the sustainable development.Accordingly,the authors put forward some suggestions.

One Year Minergie-A--Switzerlands Big Step towards Net ZEB

The first available label standardizing a zero-balanced type of building is the Swiss Standard Minergie-A. The standard prescribes an annual net zero primary energy balance for heating, domestic hot water and ventilation. Electricity consumption for appliances and lighting is excluded. Additionally, Minergie-A is the first standard worldwide which includes a requirement in regard to embodied energy. Based on an analysis of 39 Minergie-A buildings, this paper shows that a wide range of different energy concepts and embodied energy strategies are possible in the scope of the label. The basis of all Minergie-A buildings is a well-insulated building envelope. However, the step from the Swiss Standard Minergie-A to a Net ZEB （net zero energy building） standard which includes electricity consumption for appliances and lighting is not a very big one. Increasing the size of the photovoltaic system is sufficient in most cases. Anyway, some of the Minergie-A buildings evaluated are also Net ZEBs. In this paper, it is also shown that the net zero balance during the operational phase of Net ZEBs clearly outweighs the increased embodied energy for additional materials in a life cycle energy analysis.

A Sustainability Total Management Model Applied to the Product Life Cycle

In this worldwide consumer society the quest for new and more sophisticated products is ever present often leaving an unsustainable toll on the Earth＇s resources to the point where some commodities are reduced to levels of scarcity The growing challenge for product creators is to provide new products that have the least impact on the environment. The need for sustainable products is growing annually but often product creators are either unwilling to engage or are uninformed as to how to engage with the sustainable creation processes. There is a requirement for a cohesive management strategy that can both inform industrialists and provide the tools for the implementation of a sustainable approach to product design and the product life cycle. This paper reviews several publications and builds on previous work （Johnson, Gibson, ＆ Barrans, 2011）, enhancing the commonly used Life Cycle Analysis （LCA） and creating a complete management strategy, which is the Sustainability Enhancement Program （SEP）. This incorporates ISO Standards as an operating platform. Embodied Energy （Ashby, 2012） is used as a metric by SEP so that the value of energy input within any product can be measured and reduced in the future product iterations.

An input-output model for energy accounting and analysis of industrial production processes： a case study of an integrated steel plant

To promote sustainability, it has become increasingly vital to properly account material and energy flows in industrial production processes. Therefore, a generic process-level input-output （IO） model was developed to provide an integrated energy （material） accounting and analysis approach for industrial production processes. By extending the existing processlevel IO models, the production, usage, export and loss of by-products were explicitly considered in the proposed IO model. Moreover, the by-products allocation procedures were incorporated into the proposed IO model to reflect individual contributions of products to energy consumption. Finally, the proposed model enabled calculating embodied energy of main products and total energy consumption under hierarchical accounting scope. Plant managers, energy management consultants, governmental officials and academic researchers could use this input-output model to account material and energy flows, thus calculating energy consumption indicators of a production process with their specific system boundary requirements. The accounting results could be further used for energy labeling, identifying bottlenecks of production activities, evaluating industrial symbiosis effects, improving materials and energy utilization efficiency, etc. The model could also be used as a planning tool to determine the effect that a particular change of technology and supply chains may have on the industrial production processes. The proposed model was tested and applied in a real integrated steel mill, which also provided the reference results for related researches. At last, some concepts, computational issues and limi- tations of the proposed model were discussed.

Energy globalization of China:Trade,investment,and embedded energy flows

China is in a critical period of transforming from the oil and gas era to the renewable energy era.To better understand the process of energy interaction between China and the rest of the world,this study aimed to investigate the basic theoretical cognition of global energy interaction and analyze the pattern and changes of energy interaction between China and the rest of the world with the method of complex networks,multi-region input-output analysis,and other technical methods.The main findings are as follows:(1)Chinas coal-based energy production structure and the huge demand for oil and gas indicate that ensuring overseas oil and gas supply is the most direct logic of energy interaction between China and the rest of the world,and the interaction scopes are mainly concentrated in oil-and gas-rich countries and regions.(2)With the development of renewable energy,the logic of energy interaction of China with the rest of the world has changed from countries and regions rich in oil and gas to countries with global renewable energy development and installation needs for its comparative advantages for manufacturing,which forms a renewable energy trade map that covers all major countries and regions in the world.(3)The overseas energy investment target of China has expanded from a limited number of host countries to Europe,Southeast Asia,and other countries and regions.The investment business is not only limited to the oil and gas field,but also expanded to solar energy,wind energy,hydro-power,and other renewable electricity generation projects.(4)As a global manufacturing and trading power,part of the energy consumed by China is embodied in the global production network and trade network for redistribution.The scope of energy interactions between China and the world will further expand to countries with general commodity trade relations with China,forming the global“energy hub”function.This study can provide a theoretical perspective and decision-making for a deeper understanding of the energy interactions between China and the world,maintaining national energy security,and participating in global energy economic governance.

Exports-driven primary energy requirements and the structural paths of Chinese regions

As the major primary energy importer in the world,China has engaged in considerable efforts to ensure energy security.However,little attention has been paid to China’s embodied primary energy exports.Separating the international export from regional final demand,this paper focuses on quantifying provincial primary energy requirement arising from China’s exports,and tracing its concrete interprovincial supply chains using multi-regional input-output analysis and structural path analysis.Results show that China’s embodied primary energy uses in exports(EEE)reached 633.01 Mtce in 2012,compared to 565.15 Mtce in 2007.Four fifths of the EEE were supplied through interprovincial trade.Eastern coastal provinces accounted for nearly 70%of the national total EEE,while their primary energy supply mainly sourced from the central and western provinces.Most interprovincial supply chain paths of embodied primary energy exports were traced to the coal mining sectors of Shanxi,Inner Mongolia and Shaanxi.Critical receiving sectors in the final export provinces were Chemical industry,Metallurgy,Electronic equipment,Textile and other manufacturing sectors.Important transmission sectors were Electricity and hot water production and supply and Petroleum refining,coking,etc.In view of the specific role of exports in primary energy requirements,provincial energy uses are largely dependent on its domestic trade position and degrees of industrial participation in the global economy.Managing critical industrial sectors and supply chain paths associated with the international exports provide new insights to ensure China’s energy security and to formulate targeted energy policies.

What leads to variations in the results of life-cycle energy assessment?An evidence-based framework for residential buildings

Residential buildings are one of the major contributors to climate change due to their significant impacts on global energy consumption.Hence,most countries have introduced regulations to minimize energy use in residential buildings.To date,the focus of these regulations has mainly been on operational energy while excluding embodied energy.In recent years,extensive studies have highlighted the necessity of minimizing both embodied energy and operational energy by applying the life-cycle energy assessment(LCEA)approach.However,the absence of a standardized framework and calculation methodology for the analysis of embodied energy has reportedly led to variations in the LCEA results.Retrospective research endeavoured to explore the causes of variations,with a limited focus on calculating embodied impacts.Despite the undertaken attempts,there is still a need to investigate the key parameters causing variations in LCEA results by examining methodological approaches of the current studies toward quantifications of embodied and operational energies.This paper aims to address three primary questions:‘what is the current trend of methodological approach for applying LCEA in residential buildings?’;‘what are the key parameters causing variations in LCEA results?’;and‘how can the continued variations in the application of LCEA in residential buildings be overcome?’.To this end,40 LCEA studies representing 157 cases of residential buildings across 16 countries have been critically reviewed.The findings reveal four principal categories of parameters that potentially contribute to the varying results of LCEAs:system boundary definition,calculation methods,geographical context,and interpretation of results.This paper also proposes a conceptual framework to minimize variations in LCEA studies by standardizing the process of conducting LCEAs.