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1.
The increasing energy demands along with the expected depletion of fossil fuels have promoted to search for alternative fuels that can be obtained from renewable energy resources. Biodiesel as a renewable energy resource has drawn the attention of many researchers and scientists because its immense potential to be part of a sustainable energy mix in near future.This report attempts to compile the findings on current global and Malaysian energy scenario, potential of biodiesel as a renewable energy source, biodiesel policies and standards, practicability of Jatropha curcas as a biodiesel source in Malaysia as well as impact of biodiesel from Jatropha curcas. Final part of this report also describes the development of biodiesel market in Malaysia.The paper found that Jatropha curcas is one of the cheapest biodiesel feedstock and it possesses the amicable fuel properties with higher oil contents compared to others. Being non edible oil seed feedstocks it will not affect food price and spur the food versus fuel dispute. Jatropha can be substituted significantly for oil imports. Jatropha biodiesel has potential to reduce GHG emission than diesel fuel and it can be used in diesel engine with similar performance of diesel fuel. Jatropha curcas has an immense contribution to develop rural livelihoods too. Finally biodiesel production from Jatropha is eco-friendly and offers many social and economical benefits for Malaysia and can play an increasingly significant role to fulfill the energy demand in Malaysia.  相似文献   

2.
Jatropha was identified as a potential feedstock to satisfy off-grid and on-grid energy solutions. However, the potential has been questioned due to agronomic frustrations, the lack of an organized value chain and heavy criticism on biofuels due to emissions triggered by land use change (LUC). To contribute to the realistic integration of Jatropha in rural development, this article proposes a modeling approach to probe the feasibility of Jatropha-based electrification in rural Africa and the layout of such a value chain.A multi-component modeling setup is presented, featuring a life cycle inventory, spatial modeling and the optimization model, OPTIMASS. In this modeling setup, OPTIMASS is parameterized with data regarding the global warming potential and the potential location of each operation in the value chain including cultivation sites and related LUC emissions. This enables OPTIMASS to spatially design the Jatropha-based on-grid and off-grid electrification value chain (i.e. cultivation, transport and storage, biofuel production and electricity generation) in Southern Mali with minimal GWP to reach 10% substitution of fossil fuels for Jatropha in electricity production for a current and two future electricity demand scenarios.Analysis of the optimization results demonstrates that emissions from transporting the oil are lower than LUC emissions per harvestable seed of other sites. Finally, it can be said that harnessing the entirety of the Jatropha value chain is crucial to make it GWP competitive relative to fossil fuels in which the location of plantations is crucial to attain low LUC-related emissions and viable yields.  相似文献   

3.
Biodiesel is a renewable and sustainable biofuel. There are various production processes to produce biodiesel from different kinds of raw materials. In this study, the environmental impacts of biodiesel production from non-edible Jatropha oil and waste cooking oil (WCO) were investigated and compared using systematic life cycle assessment. The results show that crops growing and cultivation of non-edible Jatropha curcas lead to higher environmental impacts compared to WCO process. However, biodiesel production process from Jatropha oil has better performance because the WCO process needs to consume variety of chemicals and requires a large amount of energy for the pretreatment of raw WCO and further chemical conversion to biodiesel. Results also indicate that the collection mechanism of WCO has significant contributions towards environmental impacts. In general, biodiesel production from Jatropha oil shows higher impacts for damage categories of climate change, human health and ecosystem quality whereas biodiesel production from WCO has more severe environmental impacts for resource category. The total environmental impact is 74% less in case of using WCO as raw material compared to non-edible Jatropha oil.  相似文献   

4.
刘鸿鹏  赵景柱 《中国能源》2007,29(12):13-17
国际市场油价不断攀升,对亚太发展中国家经济增长带来巨大影响和挑战。许多国家都采取各种措施,积极应对,调整和制定能源政策,通过改善提高能源利用效率,鼓励开发利用可再生能源,积极开展区域合作,优化资源配置,降低对石油资源的依赖,保障能源安全。本文分析了当前油价对经济发展的影响,介绍了部分亚太国家应对油价上涨的能源政策,指出保障能源安全,实现可持续发展是亚太国家能源政策的唯一选择。  相似文献   

5.
This paper proposes a methodology for thermodynamic model analysis of Jatropha biodiesel engine in combination with Taguchi’s optimization approach to determine the optimum engine design and operating parameters. A thermodynamic model based on two-zone Weibe’s heat release function has been employed to simulate the Jatropha biodiesel engine performance. Among the important engine design and operating parameters 10 critical parameters were selected assuming interactions between the pair of parameters. Using linear graph theory and Taguchi method an L16 orthogonal array has been utilized to determine the engine test trials layout. In order to maximize the performance of Jatropha biodiesel engine the signal to noise ratio (SNR) related to higher-the-better (HTB) quality characteristics has been used. The present methodology correctly predicted the compression ratio, Weibe’s heat release constants and combustion zone duration as the critical parameters that affect the performance of the engine compared to other parameters.  相似文献   

6.
Biodiesel either in neat form or as a mixture with diesel fuel is widely investigated to solve the twin problem of depletion of fossil fuels and environmental degradation. The main objective of the present study is to compare performance, emission and combustion characteristics of biodiesel derived from non edible Jatropha oil in a dual fuel diesel engine with base line results of diesel fuel. The performance parameters evaluated were: brake thermal efficiency, brake specific fuel consumption, power output. As a part of combustion study, in-cylinder pressure, rate of pressure rise and heat release rates were evaluated. The emission parameters such as carbon monoxide, carbon dioxide, un-burnt hydrocarbon, oxides of nitrogen and smoke opacity with the different fuels were also measured and compared with base line results. The different properties of Jatropha oil after transestrification were within acceptable limits of standards as set by many countries. The brake thermal efficiency of Jatropha methyl ester and its blends with diesel were lower than diesel and brake specific energy consumption was found to be higher. However, HC, CO and CO2 and smoke were found to be lower with Jatropha biodiesel fuel. NOx emissions on Jatropha biodiesel and its blend were higher than Diesel. The results from the experiments suggest that biodiesel derived from non edible oil like Jatropha could be a good substitute to diesel fuel in diesel engine in the near future as far as decentralized energy production is concerned. In view of comparable engine performance and reduction in most of the engine emissions, it can be concluded and biodiesel derived from Jatropha and its blends could be used in a conventional diesel engine without any modification.  相似文献   

7.
Jatropha curcas L. is chosen as an ideal biodiesel crop in China because its seed kernel has high oil content (43-61%) and it does not compete with food. Its oil is non-edible, and the trees can resist drought and grow on barren and marginal lands without using arable land. This article reviews the history of Jatropha, current development status and problems in its seeds, propagation, plantation management, oil extraction, biodiesel processing and other value-added products production techniques in China. The commercial production of seed, oil and biodiesel as well as research advancement in China is also introduced and discussed. Examples about our new bred mutant and selected high-oil-yield Jatropha varieties, high-qualified produced biodiesel, and biodiesel pilot plant are presented. Finally, future prospects of Jatropha biodiesel industry in China are discussed.  相似文献   

8.
J. Narayana Reddy  A. Ramesh   《Renewable Energy》2006,31(12):1994-2016
A single cylinder, constant speed, direct injection diesel engine was operated on neat Jatropha oil. Injection timing, injector opening pressure, injection rate and air swirl level were changed to study their influence on performance, emissions and combustion. Results have been compared with neat diesel operation. The injection timing was varied by changing the position of the fuel injection pump with respect to the cam and injection rate was varied by changing the diameter of the plunger of the fuel injection pump. A properly oriented masked inlet valve was employed to enhance the air swirl level. Advancing the injection timing from the base diesel value and increasing the injector opening pressure increase the brake thermal efficiency and reduce HC and smoke emissions significantly. Enhancing the swirl has only a small effect on emissions. The ignition delay with Jatropha oil is always higher than that of diesel under similar conditions. Improved premixed heat release rates were observed with Jatropha oil when the injector opening pressure is enhanced. When the injection timing is retarded with enhanced injection rate, a significant improvement in performance and emissions was noticed. In this case emissions with Jatropha oil are even lower than diesel. At full output, the HC emission level is 532 ppm with Jatropha oil as against 798 ppm with diesel. NO level and smoke with Jatropha oil are, respectively 1162.5 ppm and 2 BSU while they are 1760 ppm and 2.7 BSU with diesel.  相似文献   

9.
The use of renewable forms of energy is important throughout the world, not just in countries where there are concerns over the availability of fossil fuels. In order to develop and promote suitable energy policies for the future it is necessary to gain an understanding of stakeholder views in all countries, including those with substantial fossil fuel reserves. The volume of construction work in the Gulf Cooperation Council (GCC) countries has recently been at unprecedented levels, with a huge environmental impact from construction and also from potential future energy demands. The aim of this paper is to assess the potential to exploit use of a particular, but valuable, renewable energy option: building-integrated photovoltaics (BIPV) in those countries. Such exploitation could offset, at least in some part, the future environmental burdens. A large-scale survey, followed by a number of in-depth interviews, has been undertaken in order to examine the use of BIPV. Empirical research findings are presented, and then analysed in order to determine the current viability of a large-scale expansion of BIPV in the GCC region. The research indicates that the main factors hindering expansion are high costs and the negative public perception of BIPV in the countries concerned. Proposals are therefore provided to assist the development of suitable policies and the wider introduction of viable BIPV in the GCC markets.  相似文献   

10.
In the current scenario of depleting energy resources, increasing food insecurity and global warming, Jatropha has emerged as a promising energy crop for India. The aim of this study is to examine the life cycle energy balance for Jatropha biodiesel production and greenhouse gas emissions from post-energy use and end combustion of biodiesel, over a period of 5 years. It’s a case specific study for a small scale, high input Jatropha biodiesel system. Most of the existing studies have considered low input Jatropha biodiesel system and have used NEB (Net energy balance i.e. difference of energy output and energy input) and NER (Net energy ratio i.e. ratio of energy output to energy input) as indicators for estimating the viability of the systems. Although, many of them have shown these indicators to be positive, yet the values are very less. The results of this study, when compared with two previous studies of Jatropha, show that the values for these indicators can be increased to a much greater extent, if we use a high input Jatropha biodiesel system. Further, when compared to a study done on palm oil and Coconut oil, it was found even if the NEB and NER of biodiesel from Jatropha were lesser in comparison to those of Palm oil and Coconut oil, yet, when energy content of the co-products were also considered, Jatropha had the highest value for both the indicators in comparison to the rest two.  相似文献   

11.
The Cane Resources Network for Southern Africa evaluated how bioenergy from sugarcane can support sustainable development and improve global competitiveness in the region. The assessment of six countries with good contemporary potential for expanding sugarcane cultivation described in this paper was part of their analysis. Its principal objective was to identify land where such production will not have detrimental environmental and/or socio-economic impacts. Geographic Information Systems (GIS) was used to interrogate 1 km2 resolution protected area, land cover, climate, elevation and soil data sets. To avoid detrimental impacts on biodiversity, all categories of protected areas, closed canopy forests and wetlands were excluded. To safeguard food security, all areas under food and/or cash crop production were excluded. Areas unsuitable because of climate, terrain and soil constraints were also excluded. The assessment found that almost 6 million hectares of suitable land is available in these countries, clearly suggesting that ‘land’ is unlikely to be a limiting factor in harnessing sugarcane’s bioenergy potential in the region. However, land identified as such in this study needs to be verified using better resolution, preferably ground, information.  相似文献   

12.
The paper investigates greenhouse gas (GHG) emissions from land use change associated with the introduction of large-scale Jatropha curcas cultivation on Miombo Woodland, using data from extant forestry and ecology studies about this ecosystem. Its results support the notion that Jatropha can help sequester atmospheric carbon when grown on complete wastelands and in severely degraded conditions. Conversely, when introduced on tropical woodlands with substantial biomass and medium/high organic soil carbon content, Jatropha will induce significant emissions that offset any GHG savings from the rest of the biofuel production chain. A carbon debt of more than 30 years is projected. On semi-degraded Miombo the overall GHG balance of Jatropha is found to hinge a lot on the extent of carbon depletion of the soil, more than on the state of the biomass. This finding points to the urgent need for detailed measurements of soil carbon in a range of Miombo sub-regions and similar tropical dryland ecosystems in Asia and Latin America. Efforts should be made to clarify concepts such as ‘degraded lands’ and ‘wastelands’ and to refine land allocation criteria and official GHG calculation methodologies for biofuels on that basis.  相似文献   

13.
Our objective is to assess the economic performance of Middle Eastern oil-exporting countries over the past 25 years based on their general economic characteristics (economic dependence on a depletable resource) and attendant policy requirements (transforming to a non-depletable resource-based economy). As oil-exporting countries, we assess the macroeconomic and development policies that they should have implemented and have actually implemented over time. We find that their policies have rarely been consistent with the requirements of exhaustible resource-based economies. This has resulted in a widespread misallocation of resources and a divergence from their essential goal of economic transformation.  相似文献   

14.
This study examines the primary energy consumption and energy-related CO2 emissions in Argentina, Brazil, Colombia, Mexico and Venezuela during the period 1990-2006. It also reviews important reforms in the energy sector of these countries as well as the promotion of energy efficiency (EE) and renewable energy sources (RES). Using a decomposition analysis, results indicate that even though significant reductions in energy intensity have been achieved in Colombia, Mexico and in a lesser extent in Brazil and Argentina, the reduction of CO2 emissions in these countries has not been significant due to an increased dependence on fossil fuels in their energy mix. Although the Latin American region has an important experience in the promotion of EE programs and renewable sources, the energy agenda of the examined countries focused mostly on the energy reforms during the analyzed period. The policy review suggests that further governmental support and strong public policies towards a more sustainable energy path are required to encourage a low carbon future in the region.  相似文献   

15.
This paper describes a methodology to explore the (future) spatial distribution of biofuel crops in Europe. Two main types of biofuel crops are distinguished: biofuel crops used for the production of biodiesel or bioethanol, and second-generation biofuel crops. A multi-scale, multi-model approach is used in which biofuel crops are allocated over the period 2000-2030. The area of biofuel crops at the national level is determined by a macro-economic model. A spatially explicit land use model is used to allocate the biofuel crops within the countries. Four scenarios have been prepared based on storylines influencing the extent and spatial distribution of biofuel crop cultivation. The allocation algorithm consists of two steps. In the first step, processing plants are allocated based on location factors that are dependent on the type of biofuel crop processed and scenario conditions. In the second step, biofuel crops are allocated accounting for the transportation costs to the processing plants. Both types of biofuel crops are allocated separately based on different location factors. Despite differences between the scenarios, mostly the same areas are showing growth in biofuel crop cultivation in all scenarios. These areas stand out because they have a combination of well-developed infrastructural and industrial facilities and large areas of suitable arable land. The spatially explicit results allow an assessment of the potential consequences of large-scale biofuel crop cultivation for ecology and environment.  相似文献   

16.
In developing countries like India where 70% of country's petroleum needs are met by import, energy security assumes significance in view of uncertainty of supply and increasing price of petroleum fuels. Fuels of bio origin not only provide energy security, but also reduce emissions of harmful pollutants and greenhouse gases and ensure rural upliftment by increasing employment in agricultural sector. India cannot afford to produce biodiesel from edible oil seeds as it is done in the American and European countries. Extensive focus has been given on producing biodiesel from non-edible sources, specifically from Jatropha. Discrepancies between the expectation and realities regarding Jatropha as a feedstock necessitate efforts for diversification of the feedstocks. Scientific research should therefore be directed towards oilseeds like Karanja, Sal, Mahua, Neem, etc. that are widely available and sustainable to the diverse socio-economic and environmental conditions of rural India. Among them the evergreen neem with its wide availability and various useful uses may be a potential feedstock for biodiesel production. In this paper attempts have been made to overview the morphology of neem tree, various useful uses, physical and chemical characteristics of neem oil and optimized production process for biodiesel production from neem oil.  相似文献   

17.
Diesel engines have proved its utility in transport, agriculture and power sector. Environmental norms and scared fossil fuel have attracted the attention to switch the energy demand to alternative energy source. Oil derived from Jatropha curcas plant has been considered as a sustainable substitute to diesel fuel. However, use of straight vegetable oil has encountered problem due to its high viscosity. The aim of present work is to reduce the viscosity of oil by heating from exhaust gases before fed to the engine, the study of effects of FIT (fuel inlet temperature) on engine performance and emissions using a dual fuel engine test rig with an appropriately designed shell and tube heat exchanger (with exhaust bypass arrangement). Heat exchanger was operated in such a way that it could give desired FIT. Results show that BTE (brake thermal efficiency) of engine was lower and BSEC (brake specific energy consumption) was higher when the engine was fueled with Jatropha oil as compared to diesel fuel. Increase in fuel inlet temperature resulted in increase of BTE and reduction in BSEC. Emissions of NOx from Jatropha oil during the experimental range were lower than diesel fuel and it increases with increase in FIT. CO (carbon monoxide), HC (hydrocarbon), CO2 (carbon dioxide) emissions from Jatropha oil were found higher than diesel fuel. However, with increase in FIT, a downward trend was observed. Thus, by using heat exchanger preheated Jatropha oil can be a good substitute fuel for diesel engine in the near future. Optimal fuel inlet temperature was found to be 80 °C considering the BTE, BSEC and gaseous emissions.  相似文献   

18.
加速发展我国生物航空燃料产业的思考   总被引:2,自引:0,他引:2  
姚国欣 《中外能源》2011,16(4):18-26
为了减少温室气体排放,应对欧盟征收碳排放费用,加速发展生物航空燃料产业已引起许多国家的高度重视。各国已成功进行了多次军用和民用飞机采用混合生物航空燃料或生物航空燃料的试飞,但目前仍处于试飞和安全性评估阶段,尚未实现商业化生产。一些国家已经或正在建设生物航空燃料的示范装置/工业装置,所采用的技术一类是两段加氢,另一类是气化合成。其中UOP公司开发的两段加氢技术要解决的技术难点主要是强放热反应会引起催化剂床层温度超标;而简化合成气生产工艺是生物质气化合成生产生物航空燃料的关键所在。未来生物航空燃料工厂的原料和生产技术主要有海藻油两段加氢和生物丁醇转化生产生物航空燃料。加速发展我国生物航空燃料产业的主要问题是原料来源和技术来源。我国三大石油公司建设的麻风树种植基地共240×104亩,全部建成投产后每年可以得到麻风果油64.8×104t,预计2020年我国建设的能源林基地可提供600×104t以上的生物柴油原料,2015年农作物秸秆可达到9×108t,现在的问题是要尽快落实到位;从我国现有技术和新技术开发情况看,利用具有完全自主知识产权的技术还是有条件的。同时,加速发展我国生物航空燃料产业也离不开政府有关部门的重视和支持。  相似文献   

19.
Burning agricultural residue adversely affects air quality and results in a loss of valuable nutrients required to improve soil quality. Sustainable use of crop residue can reduce air pollution from open field burning. In addition to the mandatory regulation on burning crop residue, the Chinese government also promotes the sustainable use of crop residue by subsidizing residue chopper machines and establishing agricultural demonstration sites. This paper documents the trends of crop residue utilization and evaluates the effectiveness of different regulations and technology policies toward the sustainable use of crop residue in Northeast China. Using a unique household level panel dataset, our regression results show that the ban on burning crop residue does not reduce crop residue burning, while increased availability of residue choppers induces farmers to adopt residue retention. Establishing demonstration projects also helps promote the acceptance of residue retention. Given the low level of availability of residue choppers and demonstration projects and their effectiveness, our results recommend further supporting the spread of residue chopper machines through subsidization and establishing demonstration projects. This paper also lends experience to other developing countries that have similar issues.  相似文献   

20.
Many countries are using policy incentives to encourage the adoption of energy-efficient hot water heating as a means of reducing greenhouse gas emissions. Such policies rely heavily on assumed performance factors for such systems. In-situ performance data for solar and heat pump hot water systems, however, are not copious in the literature. Otago University has been testing some systems available in New Zealand for a number of years. The results obtained are compared to international studies of in-situ performance of solar hot water systems and heat pump hot water systems, by converting the results from the international studies into a single index suitable for both solar and heat pump systems (COP). Variability in the international data is investigated as well as comparisons to model results. The conclusions suggest that there is not too much difference in performance between solar systems that have a permanently connected electric boost backup and heat pump systems over a wide range of environmental temperatures. The energy payback time was also calculated for electric boost solar flat plate systems as a function of both COP and hot water usage for a given value of embodied energy. The calculations generally bode well for solar systems but ensuring adequate system performance is paramount. In addition, such systems generally favour high usage rates to obtain good energy payback times.  相似文献   

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