Energy Consumption Coefficient Research Articles

Mathematical modeling and environmental analysis of heat pumps integrated in aprocess to treat spent pickling liquors

Spent pickling liquors are hazardous waste due to their high concentration of metals and presence of several acids.Different processes are developed for treatment of spent pickling liquors aiming to energy efficiency and there are few works in literature about the use of heat pumps (energy efficient and environmentally friendly process) to this purpose. In this article a new process for regeneration of spent pickling liquors producing fertilizers (FeSO4, ZnSO4, FeSO4·7H2O, ZnSO4·7H2O) and integrated with heat pumps is developed. A vapor compression heat pump with indirect expansion is used in evaporation and crystallization section. A sensitivity analysis is carried out to evaluate the effect of heat pump parameters on coefficient of performance. Through response surface a mathematical model is developed for coefficient of performance, CO2 emissions and primary energy consumption. In addition a factorial design allows to evaluate the significance of same factors on them. In this way process parameters and not heat pump parameters are used for factorial design: the integration of heat pumps is more enhanced.Results show that overall the two heat pumps, compared to an industrial boiler, allow a reduction of 38% of CO2 emissions and Total Equivalent Warming Impact, reduction of 39% and 57% on tons of equivalent petroleum and costs respectively, according to European Union climate package.Economical incentives in terms of white certificates are obtained so the process is more economically feasible. A Life Cycle Analysis is carried out to evaluate the environmental advantage of heat pumps over the industrial boilers. Results show that the environmental sustainability of all heat pump systems could improve with the greater penetration of renewables in the electricity mix.The future construction of the plant will allow to verify the obtained results in order to realize a more accurate mathematical model that optimizes all process.

Comprehensive Evaluation of Energy Intensity Change for 1997- 2012 Based on Input-output Analysis: Evidence from Beijing

As the capital of China, Beijing is regarded as a major metropolis in the world. Study of the variation in temporal energy intensity generated by the driving forces in Beijing can provide guidance for policy decisions on energy consumption in global metropolises. In this paper, we established Beijing energy-input-output tables from 1997 to 2012 in 2002 constant price. Based on the tables we use the structural decomposition analysis (SDA) to decompose energy intensity into five determining factors: Energy input coefficient, technology coefficient (Leontief inverse coefficient), final demands structure by product, final demands by category and final energy consumption coefficient. The results show that (1) During 1997 and 2012, Beijing energy intensity had continued to decline, and the energy input coefficient and final demands by category are the main factor help to decrease the energy intensity. (2) Energy input coefficient plays a vitally important role to energy intensity decrease, which may be due to the increase of the proportion of the tertiary industry. (3) The change of final demands structure by product is a driving force to make energy intensity rising except for 2002-2007, and technology coefficient (Leontief inverse) has impact on energy intensity increase except for 2007-2012. (4) The effect of final energy consumption coefficient is gradually weakened role on energy intensity. This study showed how the “top-down” IO-SDA methodology was implemented on a city scale. Policy implications from this study would be helpful for addressing energy consumption in global capital cities and metropolises.

The impacts of migrant workers consumption on energy use and CO2 emissions in China

China has a large number of rural–urban migrant workers in the “semi-urban” states, and their consumption pattern differs from that of rural residents and urban residents. To ensure that society develops sustainably and stably, it is necessary to be concerned about the issues of migrant workers. Based on the data gathered and processed, this paper focuses on the impacts of the consumption of China’s migrant workers on energy use and CO2 emissions using the input–output method. The results show that: the living conditions, health care and allocation of educational resources have not been effectively ensured for migrant workers. The total CO2 emission per capita of migrant workers is relatively low, at two-thirds of the national average and less than one-third that of urban residents. Marginal energy consumption and marginal carbon emission coefficients of migrant workers are slightly lower than the national average level, at 4.9 tce (tonne of standard coal equivalent) per million yuan and 11.6 t CO2 per million yuan lower than those of urban residents. The sectors of food manufacture, and production and distribution of electricity make the greatest contributions to the total carbon emissions of migrant workers, at up to 36.3 %. The citizenization of migrant workers will lead to an increase of 272 million tons of CO2 emissions of primary energy, and the top ten sectors, led by the sectors of electricity production and distribution, and health, will produce more than 60 % of the total increase in carbon emissions. With the acceleration of urbanization and citizenization, the total carbon emissions embodied in the consumption of migrant workers are likely to rise. Further efforts are required to control and reduce the indirect carbon emission, such as by improving energy price mechanism and optimization of the power structure.

Experimental Analysis on Vapour Compression Refrigeration System Using Nanolubricant with HFC-134a Refrigerant

This paper investigates the reliability and performance of a refrigeration system using nanolubricant with 1, 1, 1, 2-Tetrafluoroethane (HFC-134a) refrigerant. Mineral Oil (MO) is mixed with nanoparticles such as Titanium Dioxide (TiO2) and Aluminium Oxide (Al2O3). These mixtures were used as the lubricant instead of Polyolester (POE) oil in the HFC-134a refrigeration system as HFC-134a does not compatible with raw mineral oil. An investigation was done on compatibility of mineral oil and nanoparticles mixture at 0.1 and 0.2 grams / litre with HFC-134a refrigerant. To carry out this investigation, an experimental setup was designed and fabricated in the lab. The refrigeration system performance with the nanolubricant was investigated by using energy consumption test. The results indicate that HFC-134a and mineral oil with above mentioned nanoparticles works normally and safely in the refrigeration system. The refrigeration system performance was better than the HFC-134a and POE oil system. Thus nanolubricant (Mixture of Mineral Oil (MO) and nanoParticles) can be used in refrigeration system to considerably reduce energy consumption and better Coefficient of Performance (COP).

Analysis and efficiency enhancement of a boil-off gas reliquefaction system with cascade cycle on board LNG carriers

In this paper, an LNG boil-off gas (BOG) reliquefaction plant operating in accordance with cascade vapor compression cycles, using propylene and ethylene as refrigerants, on board LNG carriers is investigated. As consequence of the analysis results, a new and original design is proposed to reduce power consumption and improve its exergy efficiency. Through energy and exergy analysis, a thermodynamic model is carried out to analyse and evaluate operating conditions as well as to obtain performance values such as the Coefficient of Performance (COP), exergy efficiency, irreversibilities and specific energy consumption. The thermodynamic analysis is performed using the Engineering Equation Solver (EES) software environment. The results of the improved design implemented on the reliquefaction plant for LNG tank conditions of -160.82°C, a plant BOG input temperature of −125°C and 25°C seawater, give COP values of 0.22 and an exergetic efficiency of 37%, such values being 22.22% and 19.35% greater than the original design. The specific energy consumption decreases 14.66% to 0.64kWh per kg/s of natural BOG. The proposal for improving efficiency is founded on BOG cold energy recovery and BOG compression heat rejection with cooling water in the intercoolers.

Decreasing energy use and influence to environment by radiant panel heating using different energy sources

In Serbia, radiant heating is increasingly used. Also, in Serbia, the largest portion of produced electricity is from the fossil fuels which results in a high value of primary energy consumption coefficient (R). This situation raises the question of the justification of the use of ground sources heat pump (GHSP) over natural gas boiler and GSHP with PV array. Also, the impact of the embodied energy and embodied carbon was included in this paper. The operation of this house is simulated by software EnergyPlus. The results indicated that the newly-developed floor-ceiling radiant heating system has the best performances and classical ceiling heating has the worst performances. However in future with decrease of R, it is shown that the panel heating powered by GSHP may have lower total energy consumption than that of such a system powered by natural gas. For the wall panel heating, this would happen for the highest value of R, while in the case of the ceiling heating, it would appear for the lowest value of R.

Experimental investigation on a novel temperature and humidity independent control air conditioning system – Part II: Heating condition

Air source heat pump is a widely adopted system for winter heating in Central China and South China due to its high energy efficiency and low maintenance cost. However, such systems cannot produce any latent capacity resulting in decreased indoor air quality. Newly developed temperature and humidity independent control system (THIC) provides a solution to this problem. In this study, a novel THIC system was introduced and experimentally investigated under heating condition, which consisted of a solid desiccant heat pump (SDHP) and a variable refrigerant flow (VRF) air conditioning system to handle the latent load and sensible load, respectively. An experimental setup of the joint SDHP and VRF system (JDVS) was established, and the system was evaluated by indoor air condition, energy consumption and system coefficient of performance (COP). In addition, the proposed JDVS system was compared with widely adopted joint heat recovery ventilator (HRV) and VRF system (JHVS). Experimental results show that JDVS can keep indoor humidity ratio at about 50%RH, however JHVS can only increase the indoor humidity ratio to around 30%RH. In addition, JDVS can achieve energy saving of 9.3%, while the COP of JDVS increases by 45.2% compared with JHVS.

Calculation of embodied energy in Sino-USA trade: 1997–2011

In order to find efficient trade measures to reduce China׳s energy consumption and to provide theoretical support for the climate talks between China and America, we investigate the impact of Sino-USA trade on energy consumption from the perspective of embodied energy. An Environmental Input–Output Life Cycle Assessment (EIO-LCA) model was established to calculate the total energy consumption coefficient, the direct consumption coefficient and the complete consumption coefficient of the sectors of the national economies of China and America. After taking into consideration the data of every sector of the national economy in Sino-USA trade, energy embodied in the import and export trade between China and America was calculated to verify the real energy flows in Sino-USA trade. The research results suggest the following: China is the net exporter of embodied energy in Sino-USA trade, and coal, crude oil and natural gas are the major components. In 1997–2011, the net exports of China׳s embodied energy totaled 1523,082,200t of standard coal, the amount of China׳s energy consumption increased by 895,527,900t of standard coal, and America׳s energy consumption decreased by 11,871,200t of standard coal as a result of Sino-USA trade. On this basis, corresponding policies and recommendations are proposed.

Water Supply Pumping Station Energy Consumption Analysis and Energy Saving Research Based on the Energy Consumption Coefficient

From the view point of efficiency, the energy consumption coefficient was used as the energy utilization evaluation index in a water supply pumping system, and through the comparative analysis between the energy consumption coefficient and the pump efficiency, the past pump efficiency that was used as the economic index in the system could not completely and scientifically reflect the energy utilization rate of the system, while the energy consumption coefficient could intuitively reflect conveying unit volume of liquid consumption in a water supply pumping system. Based on the theory of energy consumption coefficient, the comprehensive analysis of different energy saving methods, energy saving space estimation, and average energy consumption coefficient calculation under variable conditions of the system in a water supply pumping system can give a specific guidance scheme of energy saving to the system, and it has a guidance and reference significance to the energy saving reform in the water supply pumping system.

Performance simulation of a joint solid desiccant heat pump and variable refrigerant flow air conditioning system in EnergyPlus

Temperature and humidity independent control (THIC) system has become an attractive alternative to conventional HVAC systems for its merits of energy-saving. In this paper, a novel solid desiccant heat pump is introduced and integrated with a conventional variable refrigerant flow air conditioning system (VRF) to form a THIC system. A standalone module of the SDHP is developed and the integration of the proposed THIC system is established based on EnergyPlus. Performance of this joint SDHP and VRF system (JDVS) is investigated in an office room. Parametric investigation results show that performance of SDHP varies greatly with the change of ambient air condition and part load ratio. Then, performance of JDVS in terms of capacity, energy consumption and system coefficient of performance (COP) is studied under summer and winter conditions. Finally, comparison study with the conventional joint heat recovery ventilator (HRV) and VRF system (JHVS) is conducted. Simulation results show that JDVS could obtain a better indoor thermal comfort while consuming less energy compared to JHVS. Through the whole year, JDVS consumes 18.7% less energy compared to JHVS. In addition, 85.5% of the indoor condition provided by JDVS falls in the comfort zone, and 35.4% provided by JHVS falls in the comfort zone.

EE-ARQ: a Green ARQ-Based Algorithm for the Transmission of Video Streams on Noise Wireless Channels

The challenge in the next future is to increase the energy efficiency of telecommunications networks, and specifically wireless devices that present the highest energy consumption coefficient per bit transmitted among all the networking devices. However, making a network device green can cause performance deterioration. The target of this paper is to propose a new algorithm for the transmission of multiplexed rate-controlled multimedia streams over wireless channels. The algorithm is an energy-efficient variant of ARQ to exploit the correlation of the wireless channel behavior. In addition, in order to compensate transmission bandwidth reduction due to the energy saving policies, a cross-layer approach is applied introducing a source Rate Controller working to modify the video quality according to the state of the transmission buffer. An analytical model of the whole system is presented in order to evaluate performance and provide some guidelines to design the configuration parameters of the proposed algorithm.

The impact of human behavior on ecological threshold: Positive or negative?—Grey relational analysis of ecological footprint, energy consumption and environmental protection

Human behavior has the positive and negative impact on ecosystem. To study the interaction between ecosystem and behavior system, per-capita energy ecological footprint (EEF) is selected as the ecosystem threshold. Elasticity coefficient of environmental investment (ECEI) and elasticity coefficient of energy consumption (ECEC) represent the positive and negative human impact on ecosystem, respectively. It takes Shanghai, China as the empirical area to implement grey relational analysis of per-capita EEF (consist of coal, coke, fuel oil, and electricity), ECEC and ECEI from 1978 to 2010. The grey correlation coefficients show that negative behavior of energy consumption has the closer influence on the ecosystem than positive behavior of environmental protection. Electricity is the most significant factor of the energy consumption and the highest sensitive indicator to the environmental capital input–output. From the perspective of government policy, “energy saving” is more efficient than “emission reduction”. Reducing the negative activities is imminent in the current process of development.

Research on Influencing Mechanism of Industrial Carbon Emissions in Hebei Province

This paper calculates carbon emissions in Hebei Province based on energy consumption and carbon coefficients and adopts the index decomposition model to analyze the influence of value-added industries and carbon emissions per unit added value on carbon emissions.The results indicate that the increase of value-added industries in Hebei Province is the main factor affecting the growth of carbon emissions, but the decrease of carbon emissions per unit added value induces carbon emissions to a lesser reducing. The conclusions can offer the decision basis for reducing carbon emissions.

Analysis of the carbon dioxide concentration in the lowest atmospheric layers and the factors affecting China based on satellite observations

Carbon dioxide (CO2) is the most important anthropogenic greenhouse gas contributing to global climate change. SCIAMACHY on board ENVISAT (launched in 2002) is the first satellite instrument to monitor the changes in CO2 concentration in the lowest atmospheric layers. The temporal and spatial distribution of CO2 (2003–2009) concentration based on SCIAMACHY over China is presented and discussed. It shows an annual increase and a seasonal cycle. The CO2 annual growth rate was about 1.8 ppm year−1, with the highest value being in spring and the lowest in autumn. The CO2 concentration variation is determined by many complex factors. In this article, we analyse the important factors affecting CO2 variations, with special emphasis on terrestrial ecosystems and energy consumption. Terrestrial ecosystems are an important sink in the global carbon cycle. The relationship between CO2 concentration and Moderate Resolution Imaging Spectroradiometer (MODIS) net primary production (NPP) in 2008 is analysed. CO2 concentration is inversely proportional to NPP both in regions with high-density vegetation and in deserts. The Yunnan province has the highest NPP value and the lowest CO2 concentration, whereas the Takla Makan Desert has the lowest NPP value and the highest CO2 concentration. Energy consumption is the main emission source of atmospheric CO2. CO2 emissions from energy consumption show a steady increase in China since 1980. China's CO2 concentration variation shows a high correlation with energy consumption (coefficient of determination (R 2) > 0.8). The regions with high energy consumption are major industrial regions such as Shandong, Guangdong, Jiangsu, Zhejiang, Hebei, and Henan.

Experimental investigation of a novel configuration of desiccant based evaporative air conditioning system

A novel configuration of desiccant based evaporative cooling system for air conditioning application is developed and tested. At the beginning of the design stage of the system, an analysis is carried out in order to maximize the performance of the system. It is found based on configuration that outdoor air must be used for regeneration to increase performance of the system and so three air channels are used. Experiments are carried out to investigate the total performance of the system and performance of the components used during summer season in a hot and humid climate. Effectiveness values for both heat exchangers and evaporative coolers are calculated through this work. In addition to the cooling capacity, coefficient of performance (COP) and energy consumption of the system are also evaluated. Results show that the effectiveness for the heat exchangers and evaporative coolers are very high under different outdoor conditions. It is also shown from the results that indoor air conditions are in the range of thermal comfort zone defined by ASHRAE and expanded comfort zone for evaporative air conditioning applications.

Energy Efficiency Design Strategy of Commercial Building in Northeast Cold Regions

From the point of view of architectural design, envelope location, selection, and identify programs of envelope structure in the modern commercial building, give priority to the establishment of image of shopping malls , creating the mood of commercial and other factors. The paper will establish the appropriate model to the impact of the shape coefficient of Commercial building energy consumption in cold regions, validity analysis used the building energy evaluation software named Autodesk Ecotect to provide adequate theoretical basis of energy conservation design strategies.

Structural decomposition analysis on China’s energy intensity change for 1987–2005

There has been considerable debate about the major factors responsible for the dramatic decline of China’s energy intensity in the 1980s and 1990s. However, few detailed analysis has been done to explain the fluctuation in energy intensity during 2002–2005. In this paper, we use the structural decomposition analysis (SDA) to decompose energy intensity into five determining factors: Energy input coefficient, technology coefficient (Leontief inverse coefficient), final demands structure by product, final demands by category and final energy consumption coefficient. We then further decompose two coefficients, energy input coefficient and technology coefficient, into structure and real coefficient. Empirical study is carried out based on the energy-input-output tables from 1987 to 2005 in 2000 constant price. The results show that between 1987 and 2002, energy input structure accounts for most of the decline in energy intensity. However, the input structure and final demands structure by product explain the increase of the energy intensity between 2002 and 2005.

旅游风景区旅游交通系统碳足迹评估——以南岳衡山为例

PDF HTML阅读 XML下载 导出引用 引用提醒 旅游风景区旅游交通系统碳足迹评估——以南岳衡山为例 DOI: 10.5846/stxb201110011445 作者: 作者单位: 衡阳师范学院 资源环境与旅游管理系,湖南 衡阳,衡阳师范学院 资源环境与旅游管理系,湖南 衡阳,衡阳师范学院 资源环境与旅游管理系,湖南 衡阳,衡阳师范学院 资源环境与旅游管理系,湖南 衡阳 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(41101163);教育部人文社科青年基金项目(12YJC630039);湖南省社会科学规划项目(2010YBB029);衡阳市社会科学基金项目(2011C030);衡阳师范学院青年项目(10A39) Carbon footprint evaluation research on the tourism transportation system at tourist attractions: a case study in Hengshan Author: Affiliation: Department of Geography Tourism Management,Hengyang Normal University,Hengyang,Department of Geography Tourism Management,Hengyang Normal University,Hengyang,Department of Geography Tourism Management,Hengyang Normal University,Hengyang,Department of Geography Tourism Management,Hengyang Normal University,Hengyang Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:随着全国各地旅游业的蓬勃发展,旅游风景区内碳排放总量不断攀升,严重影响了旅游业的可持续发展。选择南岳衡山旅游风景区为典型案例区,运用生命周期评价理论,构建了南岳风景区旅游交通系统碳足迹计算模型。结果表明:①从总量来看,不同类型交通方式的碳足迹情况相差甚远。公路旅游交通对旅游景区的环境威胁最大,碳足迹总量是索道旅游交通的2.6倍,人行道旅游交通的46.1倍;②从阶段构成来看,公路和索道旅游交通系统运营使用阶段碳足迹占整个生命周期的大部分,所占比率分别为79%和96%.而人行道旅游交通系统中建造施工和运营后期阶段能源消耗比较大;③从来源构成来看,在使用期内公路旅游交通的碳足迹比重最大,约占碳足迹总量的71%,其次是索道旅游交通占27%,人行道旅游交通仅占2%。研究结果有利于实现旅游风景区低碳旅游发展目标,为旅游风景区节能减排提供理论支撑。 Abstract:In recent years, there has been large-scale development in tourism in China. It is difficult to achieve sustainable development of the tourism industry because of increasing carbon emissions associated with tourist attractions. In this article, we focused on Hengshan as the case study and applied a life cycle evaluation theory to construct a carbon footprint calculation model of the tourism transportation system at a scenic spot in Hengshan. The following results were obtained: first, in terms of total volume, different types of transportation have different carbon footprints. The most energy-expensive method of reaching tourist attractions is tourist highways, which have a carbon footprint that is 2.6 times that of tourist cableways and 46.1 times that of tourist walkways. Second, in terms of the stages in which the carbon footprint is distributed, the majority of the carbon footprint of tourist highways (79%) and tourist cableways (96%) is in the operation and use stage of the life cycle. For tourist walkways, most of the energy consumption is at the construction and the later operation stages. Third, in terms of source constitution, the carbon footprint of tourist highways occupies the largest proportion (about 71%) during its useful life, followed by tourist cableways (27%) and tourist walkways (2%). The model described in this article will not only help to achieve the goals of low-carbon tourism development, but will also provide the theoretical support for saving energy and reducing emissions at tourist attractions. The following suggestions are proposed: first, it is important to increase awareness of low-carbon tourism, taking into account the transportation preferences of travelers and advocating a comprehensive means of tourist transport. Second, combined with the characteristics of the tourism infrastructure, some caution is needed when selecting low-carbon vehicles. Different types of transportation use different types of energy and have different energy consumption coefficients. Therefore, the vehicles that are most appropriate for local conditions should be selected. For the scenic spot in Hengshan, we suggest that the most appropriate vehicle is the Golden Dragon Type KLQ6702, which has a smaller carbon footprint per day than the Toyota COASTER (a ratio of approximately 1:7.2). Third, it would be advantageous to improve the energy efficiency of the other operation mechanisms at tourist attractions, and accelerate the pace of adopting low-carbon tourist transport. Optimal operation mechanisms for tourist transport can greatly reduce greenhouse gas emissions. Therefore, we need to explore new, more flexible combinations of transport systems and operations to achieve sustainable development of tourism in China. 参考文献 相似文献 引证文献

Analysis of Energy Consumption Efficiency in Diamond Circular Sawing

. Experiments of sawing granite with diamond circular blades were carried out to study the energy efficiency in circular sawing. Energy consumed by machine spindle is classified into energy used without cutting and energy used with cutting. The energy used without cutting almost increases with the improvement of peripheral speed of blade. The energy consumption coefficient, the ratio of energy used with cutting to total energy consumed by spindle, increases with the increase of material removed rate, which reveals that higher material removed rate is favor for improving energy utilization. A fixed trend of energy consumption coefficient versus material removal rate was found and it might be useful for selecting cutting parameters for low energy sawing.

Energy Analysis for Air Conditioning System Using Fuzzy Logic Controller

Reducing energy consumption and to ensure thermal comfort are two important considerations for the designing an air conditioning system. An alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. The control strategy will be proposed using the fuzzy logic controller (FLC). FLC was developed to imitate the performance of human expert operators by encoding their knowledge in the form of linguistic rules. The system is installed on a thermal environmental room with a data acquisition system to monitor the temperature of the room, coefficient of performance (COP), energy consumption and energy saving. The measurements taken during the two hour experimental periods at 5-minutes interval times for temperature setpoints of 20 o C, 22 o C and 24 o C with internal heat loads 0, 500, 700 and 1000 W. The experimental results indicate that the proposed technique can save energy in comparison with On/Off and proportional-integral-derivative (PID) control.