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1.
The concept of innovation has been used in a wide range of contexts and the theoretical development has proven to be extremely valuable to provide important insights into intra-market competition, strategy and regulatory policy. The automotive industry offers a fertile terrain for progress of the uncompleted theory building process of innovation, especially with the introduction of alternative fuels and alternative powertrain technologies.This paper investigates the concept of innovation in the context of the modern automotive industry, by focusing on the notion of regulatory innovation of alternative fuels and alternative powertrain technologies. For the purpose of analysing this issue, special attention is given to the concepts of radical and incremental innovation, which are applied to existing alternative fuels and alternative powertrain technologies, including hybrids, biofuels and hydrogen power. The article explores these three categories looking at representative case studies: the Brazilian ethanol experience with biofuels, the development of the Toyota hybrid vehicle and the technological development of hydrogen fuel cells. These categories have been selected because they represent the most important advances in cleaner production for the automotive industry.  相似文献   

2.
Modern Biomass Conversion Technologies   总被引:4,自引:2,他引:4  
This article gives an overview of the state-of-the-art of key biomass conversion technologies currently deployed and technologies that may play a key role in the future, including possible linkage to CO2 capture and sequestration technology (CCS). In doing so, special attention is paid to production of biofuels for the transport sector, because this is likely to become the key emerging market for large-scale sustainable biomass use. Although the actual role of bio-energy will depend on its competitiveness with fossil fuels and on agricultural policies worldwide, it seems realistic to expect that the current contribution of bio-energy of 40–55 EJ per year will increase considerably. A range from 200 to 300 EJ may be observed looking well into this century, making biomass a more important energy supply option than mineral oil today. A key issue for bio-energy is that its use should be modernized to fit into a sustainable development path. Especially promising are the production of electricity via advanced conversion concepts (i.e. gasification and state-of-the-art combustion and co-firing) and modern biomass derived fuels like methanol, hydrogen and ethanol from ligno-cellulosic biomass, which can reach competitive cost levels within 1–2 decades (partly depending on price developments with petroleum). Sugar cane based ethanol production already provides a competitive biofuel production system in tropical regions and further improvements are possible. Flexible energy systems, in which biomass and fossil fuels can be used in combination, could be the backbone for a low risk, low cost and low carbon emission energy supply system for large scale supply of fuels and power and providing a framework for the evolution of large scale biomass raw material supply systems. The gasification route offers special possibilities to combine this with low cost CO2 capture (and storage), resulting in concepts that are both flexible with respect to primary fuel input as well as product mix and with the possibility of achieving zero or even negative carbon emissions. Prolonged RD&D efforts and biomass market development, consistent policy support and international collaboration are essential to achieve this.  相似文献   

3.
为公正评价汽车代用燃料的能耗与环境效益,运用生命周期评价方法,研究了在燃料中分别添加不同比例的乙醇和甲酯2种生物质,带来的生命周期能耗和污染物排放变化,并对含氧生物质燃料的未来情景进行了预测分析.结果表明:乙醇代用燃料未降低化石燃料消耗,甲酯代用燃料可降低约20%的化石燃料消耗;几种配比的代用燃料均可降低石油消耗,甲酯代用燃料降低的趋势更加明显;各种代用燃料的温室气体排放都比较严重;乙醇代用燃料增加了NOx排放,而甲酯代用燃料可降低约50%的NOx排放;乙醇和甲酯的加入均能降低车用阶段的PM10排放;燃料生产阶段的SO2排放在整个生命周期中约占80%,必须严格控制;甲酯代用燃料可降低VOC排放.  相似文献   

4.
玉米燃料乙醇生命周期净能量分析   总被引:6,自引:1,他引:6  
张治山  袁希钢 《环境科学》2006,27(3):437-441
玉米燃料乙醇作为化石燃料的替代品,能量效率(净能量或能量比)是评价其可持续性的一个重要标准.基于生命周期清单分析原理,建立了玉米燃料乙醇的净能量分析方法.以我国夏玉米燃料乙醇的生产条件为例,计算了玉米燃料乙醇整个生命周期的能量效率并对其影响因素进行了分析,讨论了乙醇汽油混合燃料的节能效果.研究表明:玉米燃料乙醇具有一定的能量效益,干法和湿法工艺的能量效率(能量比)分别为1.25和1.04.通过玉米燃料乙醇生命周期内的能量输入比较可知,玉米生产和乙醇转化过程的化石能输入占有最大的比例,因而玉米种植过程中的氮肥、电力、柴油消耗和乙醇生产过程中蒸馏和脱水过程的能耗是影响玉米燃料乙醇能量效益的主要因素.  相似文献   

5.
Besides the apparent need to reduce greenhouse gas emissions, other important factors contributing to the renewed interest in biofuels are energy security concerns and the need of sustainable transportation fuel. Nearly 30% of the annual CO2 emissions in the U.S. come from the transportation sector and more than half of the fuel is imported. Biofuels appear to be a promising option to reduce carbon dioxide emissions, and the reliance on imported oil concomitantly. The interest on (ligno) cellulosic ethanol is gaining momentum as corn-based ethanol is criticized for using agricultural outputs for fuel production. Among many lignocellulosic feedstocks, woodchips is viewed as one of the most promising feedstocks for producing liquid transportation fuels. The renewable and carbon neutral nature of the feedstocks, similar chemical and physical properties to gasoline, and the low infrastructure cost due to the availability of fuel flex vehicles and transportation networks make (ligno) cellulosic bioethanol an attractive option. An in-depth LCA of woodchips shows that harvesting and woodchips processing stage and transportation to the facility stage emit large amount of environmental pollutants compared to other life cycle stages of ethanol production. Our analysis also found that fossil fuel consumption and respiratory inorganic effects are the two most critical environmental impact categories in woodchips production. We have used Eco-indicator 99 based cradle-to-gate LCA method with a functional unit of 4 m3 of dry hardwood chips production.  相似文献   

6.
The Chinese government is developing biomass ethanol as one of its automobile fuels for energy security and environmental improvement reasons. The cassava is an alternative feedstock to produce this ethanol fuel. Its performance of environmental impacts and energy efficiency is the critical issue. Life cycle assessment has been used to identify and quantify the environment emissions, energy consumption and energy efficiency of the system throughout the life cycle. This study investigates the entire life cycle from cassava plantation, ethanol conversion, transport, Fuel ethanol blending and distribution to its end-use. Product system of cassava-based ethanol fuel is described and it is divided into six unit processes. The environmental impacts and energy consumption of each unit process are quantified and some of the potential effects are assessed.  相似文献   

7.
Crop derived biofuels such as (bio)ethanol are increasingly applied for automotive purposes. They have, however, a relatively low efficiency in converting solar energy into automotive power. The outcome of life cycle studies concerning ethanol as to fossil fuel inputs and greenhouse gas emissions associated with such inputs depend strongly on the assumptions made regarding e.g. allocation, inclusion of upstream processes and estimates of environmentally relevant in- and outputs. Peer reviewed studies suggest that CO2 emissions linked to life cycle fossil fuel input are typically about 2.1–3.0 kg CO2 kg−1 starch-derived ethanol. When biofuel production involves agricultural practices that are common in Europe there are net losses of carbon from soil and emissions of the greenhouse gas N2O. Dependent on choices regarding allocation, they may, for wheat (starch) be in the order of 0.6–2.5 kg CO2 equivalent kg−1 of ethanol. This makes ethanol derived from starch, or sugar crops, in Europe still less attractive for mitigating climate change. In case of wheat, changes in agricultural practice may reduce or reverse carbon loss from soils. When biofuel production from crops leads to expansion of cropland while reducing forested areas or grassland, added impetus will be given to climate change.  相似文献   

8.
The success of implementing alternative fuels for road transport depends on their cost, performance and reliability. This paper focuses on the use of natural gas and LPG, hydrogen and biofuels in Europe. A brief presentation is given of their technical development status, their market potential, and barriers to their implementation in various market segments. Some market barriers are common to many new technologies, and can be overcome through adequate policy measures at European level. Generally, a combination of policies is required, and a number of supporting measures increase their effectiveness. The following policies affecting energy use in transport are discussed: market incentives, policies targeting technology and vehicle efficiency, and overall system improvement.  相似文献   

9.
This paper analyses biofuels from agricultural crops in northern Europe regarding area and energy efficiency, greenhouse gases and eutrophication. The overall findings are that direct land use changes have a significant impact on GHG balances and eutrophication for all biofuels, the choice of calculation methods when by-products are included affecting the performance of food crop-based biofuels considerably, and the technical design of production systems may in specific cases be of major importance. The presented results are essential knowledge for the development of certification systems. Indirect land use changes are recognised but not included due to current scientific and methodological deficiencies.  相似文献   

10.
Algal biofuel production and mitigation potential in India   总被引:1,自引:1,他引:0  
Energy and energy services are the backbone of growth and development in India and is increasingly dependent upon the use of fossil based fuels that lead to greenhouse gases (GHG) emissions and related concerns. Algal biofuels are being evolved as carbon (C)-neutral alternative biofuels. Algae are photosynthetic microorganisms that convert sunlight, water and carbon dioxide (CO2) to various sugars and lipids Tri-Acyl-Glycols (TAG) and show promise as an alternative, renewable and green fuel source for India. Compared to land based oilseed crops algae have potentially higher yields (5?C12 g/m2/d) and can use locations and water resources not suited for agriculture. Within India, there is little additional land area for algal cultivation and therefore needs to be carried out in places that are already used for agriculture, e.g. flooded paddy lands (20 Mha) with village level technologies and on saline wastelands (3 Mha). Cultivating algae under such conditions requires novel multi-tier, multi-cyclic approaches of sharing land area without causing threats to food and water security as well as demand for additional fertilizer resources by adopting multi-tier cropping (algae-paddy) in decentralized open pond systems. A large part of the algal biofuel production is possible in flooded paddy crop land before the crop reaches dense canopies, in wastewaters (40 billion litres per day), in salt affected lands and in nutrient/diversity impoverished shallow coastline fishery. Mitigation will be achieved through avoidance of GHG, C-capture options and substitution of fossil fuels. Estimates made in this paper suggest that nearly half of the current transportation petro-fuels could be produced at such locations without disruption of food security, water security or overall sustainability. This shift can also provide significant mitigation avenues. The major adaptation needs are related to socio-technical acceptance for reuse of various wastelands, wastewaters and waste-derived energy and by-products through policy and attitude change efforts.  相似文献   

11.
汽车代用燃料及应用前景   总被引:4,自引:0,他引:4  
介绍了已经开发使用的代用燃料氢气,甲醇,乙醇,新配方汽油,天然气,液化石油气,电动汽车等,并对代用燃料车和汽油车的环境安全性,成本,能耗消耗等方面作了比较,指出天然气,液化石油气是当前最有前途的代用燃料。  相似文献   

12.
Biofuels are heavily debated as to their potential to reduce transport-related greenhouse gas emissions. Life cycle thinking gave rise to formal evaluations of the energy balance of such fuels, which led to the vigorously conducted “corn to ethanol” debates. Just as consensus was building on such evaluations came the “carbon debt” insights, a result of applying consequential Life Cycle Assessment (LCA) backed by advanced economic modeling. Increasingly, hopes have shifted to the 2nd generation biofuels, viewed as a “technological home run”. Could this also backfire? We investigate a simple South African case in which there might not be improvements in environmental performance: a sugar mill sells its bagasse, currently used at low efficiency to provide process heat, to an advanced biofuels producer, and buys an equivalent amount of coal without investing in efficiency improvements. Seven scenarios are generated, ranging from the status quo, where no bagasse is diverted, to 100% bagasse diversion, with one scenario including an energy efficiency improvement in the sugar mill. A consequential LCA is applied to the seven scenarios, covering global warming potential (GWP), non-renewable energy use, aquatic eutrophication and terrestrial acidification. A basic financial analysis of the proposed scenarios shows that they are realistic, with potentially lucrative returns. Results show that diverting bagasse without efficiency improvements from its current use to an ethanol bio-refinery would indeed backfire for all environmental impacts studied. The base case outperforms all the other scenarios, with the 100% bagasse diversion scenario emerging the worst. Investments into energy efficiency are therefore a precondition for diverting cellulosic residues into biofuel production.  相似文献   

13.
出于能源安全的考虑及对温室气体减排的关注,世界各国近些年大力发展生物液体燃料,我国政府提倡以木薯等非粮作物为原料生产燃料乙醇。一直以来科学家们对生物液体燃料的碳效应争论激烈,争论的焦点在于原料种植对土壤碳库的影响及不同技术条件下副产品利用的评估。论文通过建立碳平衡分析模型,将原料种植对土壤碳库影响及副产品利用的替代效应纳入研究体系,评估了我国木薯燃料乙醇生产各个环节的碳排放,研究结果显示:木薯原料种植环节碳排放主要来自氮肥的使用及对土壤碳库的破坏;木薯燃料乙醇加工转化环节碳排放主要来自蒸馏和脱水过程能源消耗,改进加工转化技术对减少此环节碳排放至关重要;木薯燃料乙醇运输及储存过程碳排放较小。在现有生产技术条件下,生产单位质量(1 kg)木薯燃料乙醇平均碳排放为0.647 kg。以汽油的碳排放为参照,在目前技术水平条件下,我国木薯燃料乙醇碳排放呈现负效益;采用较为先进的双酶法中温喷射液化-大罐浓醪间歇发酵-多塔多耦合差压精馏和分子筛变压脱水技术,则其碳排放为汽油的90%;倘若能避免对土壤碳库的破坏,则这一比例下降到64%。因此,为了促进我国木薯燃料乙醇的发展,减少木薯燃料乙醇生产的碳排放,首先应该引导农民合理施肥,利用边际土地种植木薯,不转换林地、草地等土地类型的利用方式,减少对土壤碳库的破坏;此外,要开发高效节能的燃料乙醇转化技术并加强对副产品的二次利用。  相似文献   

14.
This study is to evaluate the impact of cleaner vehicles on energy systems and CO2 emissions in the transportation sector in Japan. The transportation sector has the characteristic of spending petroleum. Even when the cost of petroleum rises, conventional vehicles cannot switch fuels to alternative energy right away. Cleaner vehicles, such as fuel cell vehicles, would be one of the alternative technologies in the transportation sector. It is supposed to have excellent performance in fuel efficiency and has strong possibility to reduce CO2 drastically. This paper uses a multi-period market equilibrium model to explore the impacts of cleaner vehicles on the passenger transportation sector in Japanese energy system out to the year 2040. A Btu tax is tentatively imposed to evaluate the effect of fuel cost on energy consumption in the transportation sector. Financial parameters such as capital cost and operating cost are considered to summarize the profit in taxation case. The result of this study shows that fuel cell vehicles have a great effect on reducing CO2 emissions especially when Btu taxes are imposed, which in turn has the advantage of encouraging a more diverse set of technologies and fuels. The analysis that petroleum consumption can be reduced using fuel cell vehicles will have effects on perspectives on energy systems in Japan.  相似文献   

15.
基于能值方法的甘薯燃料乙醇产业生态系统分析   总被引:1,自引:0,他引:1  
发展燃料乙醇已成为替代能源战略下的成熟模式,但传统燃料乙醇生产的污染问题严重影响了燃料乙醇的生存和发展,因此建立以燃料乙醇生产为核心企业,包括由原料种植者、乙醇生产者、分解者、资源回收利用者等一系列利益相关者组成的产业生态系统,已成为燃料乙醇可持续发展的有效途径. 根据燃料乙醇生产过程中对废物处理和资源化利用情况,将其划分成传统生产方案(方案Ⅰ)、废物处理生产方案(方案Ⅱ)和产业生态系统方案(方案Ⅲ),并采用改进后的能值分析方法及指标体系对3种生产方案进行比较分析. 结果表明:与方案Ⅰ相比,通过废物处理和中水回用,方案Ⅱ的εEYR(能值产出率)提高了59.37%,εELR(环境负荷率)降低了75.39%;延长产业链,增加循环利用方式后,方案Ⅲ比方案Ⅰ的εEYR提高了86.19%,εELR降低了82.98%. 3种生产方案的可持续发展能力为方案Ⅰ<方案Ⅱ<方案Ⅲ.   相似文献   

16.
The resource basis of industrial energy production is still, to a large extent, in non-renewable fossil fuels, the use of which creates emissions that the ecosystem has difficulty in tolerating. The goal of industrial ecology is to substitute the non-renewable stocks with renewable flows. In this paper, a regional industrial ecosystem that relies on a power plant as its key organisation, as an anchor tenant, is considered in the context of energy production and consumption. The co-production method of heat and electricity (CHP, co-production of heat and power) is implemented in the local power plant. This method uses the waste energy from electricity production for district heat and industrial heat/steam. The fuel basis in a CHP plant can include heterogeneous waste fuels. The method has been applied, to a large extent, in only three countries in the world; Denmark, The Netherlands and Finland. Examples of CHP-based industrial ecosystems from Finland are considered. CHP is reflected upon from the viewpoint of industrial ecosystem principles.  相似文献   

17.
Production of biofuels from microalgae   总被引:1,自引:1,他引:0  
The production of biofuels from microalgae, especially biodiesel, has become a topic of great interest in recent years. However, many of the published papers do not consider the question of scale up and the feasibility of the various processes to be operated at the very large scale required if algal biofuels are to make a meaningful contribution to renewable fuels. All the steps in the process must also be very low cost. This paper discusses the unit processes required for algal biofuels production (i.e., growing the algae, harvesting, dewatering, extraction and conversion to biofuel) and their scalability. In many cases, especially in the lipid extraction step, little is known as yet as to the scalability and economic feasibility of the various processes proposed. We also highlight the key engineering and biological issues which must be resolved for the production of biofuels from microalgae to become an economic reality.  相似文献   

18.
The aim of this study is to develop a theoretical model by which to demonstrate how taxes and subsidies work as external factors to substitute fossil fuel by a forest-based biofuel. For biofuels, this study predominantly considers solid-form biomass that generates electricity; for fossil fuels, it considers coal. The model results explicated with three states by using various numeric values taken from the literature. Three states are as follows: a situation without a tax and subsidy, a situation with a biofuel subsidy, and a situation with a biofuel subsidy and a fossil fuel tax. The results of the first state exemplify current fuel market situation; those of the second indicate that the aggregate demand for biofuel has shifted upwards by around 15 % and that substitution has increased by around 18 % due to biofuel subsidies being offered. Under the third state, aggregate biofuel demand has shifted upwards by around 19 %, reduced the demand for fossil fuels by around 13 %, and increased substitution by around 31 %. This state relates to a greater sense of social welfare than other two states. It is conceivable that the joint application of taxes and subsidies will succour biofuel to supplant fossil fuel in the near future.  相似文献   

19.
在能源危机的背景下,作为重要生物能源之一的沼气已经越来越受到重视。沼气的应用目前已经不再局限于照明等传统用途。通过一系列的净化处理,沼气有了新的用途和价值,比如净化后并入天然气、作为汽车燃料等。微生物法处理沼气因其环境污染小、成本低和产生附加价值等优势成为比较热门的研究课题。文章主要对净化沼气中H2S和CO2的微生物分别进行了介绍并且对其诸多工艺中的关键影响因素进行了详细的阐述,结合现状分析提出了净化沼气中CO2和H2S的微生物在应用中存在的问题及其应用前景。  相似文献   

20.
Increasing the share of renewable energy is of principal concern for the EU energy policy. A number of policies have been adopted, and, in part, been implemented by the EU member countries. An increasing share of renewable energy implies an increasing utilisation of biofuels in general and of forest-based biomass in particular. However, in the EU, the endowment and uses of forest-base biomass are diverse suggesting that an increasing trade would become necessary in order to cost effectively increase the utilisation of forest-based biomass. The purpose of this study is to, in the presence of EU energy policy, quantify and analyse possible trade levels for forest fuels in the EU. Particularly, the consequences on trade after implementing the White Paper and the RES-E Directive are analysed. Investigating the European trade in forest fuels is important for understanding how industry sectors in the EU will be affected by the policies. The results suggest that the implementation of the White Paper and the RES-E Directive will increase the trade in forest fuels, resulting in total trade increases of up to 67 percent. Furthermore, the national net trading levels are possible to derive. Depending on policy implementation the results differ – a country that was net importing given the White Paper implementation can instead be net exporting when applying the RES-E Directive. The fact that the policy implementations will increase the trade may mitigate potential industry problems to secure the needed inputs. On the other hand, the integration of countries increases the possibility for some industries to increase their production even more, possibly strengthening any input scarcity problems. It is therefore not possible to generally conclude if a more integrated European forest fuel market, and hence an increased European forest fuel trade, will mitigate industry problems to secure their needed inputs or not.  相似文献   

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