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[en] There is growing concern that non-native plants cultivated for bioenergy production might escape and result in harmful invasions in natural areas. Literature-derived assessment tools used to evaluate invasion risk are beneficial for screening, but cannot be used to assess novel cultivars or genotypes. Experimental approaches are needed to help quantify invasion risk but protocols for such tools are lacking. We review current methods for evaluating invasion risk and make recommendations for incremental tests from small-scale experiments to widespread, controlled introductions. First, local experiments should be performed to identify conditions that are favorable for germination, survival, and growth of candidate biofuel crops. Subsequently, experimental introductions in semi-natural areas can be used to assess factors important for establishment and performance such as disturbance, founder population size, and timing of introduction across variable habitats. Finally, to fully characterize invasion risk, experimental introductions should be conducted across the expected geographic range of cultivation over multiple years. Any field-based testing should be accompanied by safeguards and monitoring for early detection of spread. Despite the costs of conducting experimental tests of invasion risk, empirical screening will greatly improve our ability to determine if the benefits of a proposed biofuel species outweigh the projected risks of invasions. (letter)
[en] Using an experiment embedded within a representative survey, this study examined the interactive effect of party identification and risk/benefit perception on public opinion about biofuels. Democrats tended to be more supportive of biofuels than Republicans. However, the effect of party identification on opinion about biofuels varied when individuals considered the risk/benefit of biofuels in different domains. Individuals who reported greater affiliation with the Democratic Party were likely to support funding biofuels research when primed with the economic risks or the social/ethical benefits of biofuels. For those who considered the social/ethical benefits of biofuels, more self-identified Democrats were likely to support biofuels production and use. However, more self-identified Democrats were less supportive of biofuels production and use when they considered the political risks of biofuels. Implications are discussed. - Highlights: • We examined public opinion about biofuels policies. • Effect of risk/benefit perception varied across respondents' party identification. • Democrats favored more research when considering economic risks or social benefits. • Democrats favored biofuels more when considering social benefits. • Democrats favored biofuels less when considering political risks
[en] An alternative to the production of fossil transportation fuels is the production of biofuels, particularly, bioethanol. One of the main opportunity areas is the reduction in the overall cost of biofuel. An approach to reduce this cost is to design and implement a supply chain (SC) that considers the quality-related properties of the biomass as well as the economies of scale to minimize the logistics and quality-related costs. This problem is formulated as a hub location problem, which has been classified as an NP-hard problem, thus, meta-heuristics are a suitable approach to solve this problem. We propose a hybrid meta-heuristic solution procedure to solve large-scale instances of a two-stage stochastic biomass-to-biorefinery hub-and-spoke network problem. This solution procedure is proposed to support the large-scale production and distribution of bioethanol by considering the variability in its moisture and ash contents. The hybrid method utilizes a simulated annealing-simplex method to find an initial solution and a tabu search-simplex method to improve the solution. Numerical experimentation was performed on a realistic case study in Texas. The findings demonstrate that the hybrid procedure outperforms the standard L-shaped (LS) method. The meta-heuristic combining simulated annealing and tabu search with the simplex method (SATS-SM) achieved 2.48% lower costs and required 96.57% less time, on average, when compared to the results from using the LS.
[en] This report explores to which extent alternative, (partially) Well-To-Wheel based fiscal systems may accelerate the introduction of low-carbon fuels and vehicles. The design of two alternative fiscal systems is described, as well as the challenges that any fiscal system must meet. The alternative systems are compared to the existing fiscal system with regard to (1) the extent to which they honour the 'polluter pays' principle, (2) the extent to which they are expected to accelerate the introduction of (alternative) gaseous fuels, liquid biofuels, and zero-emission vehicles, (3) their expected impact on the vehicle stock, and (4) a number of (undesired) side-effects. The results show that the alternative systems provide a stronger fiscal support for some alternative fuels and vehicles, but not for all.
[en] A model for planning of the biofuel production from wood of fast-growing willows, allowing to calculate the economic balance and to evaluate the degree of environmental pollution was proposed. The calculations were carried in the MS Excel. The model can be transformed easily to analyze the economic and environmental efficiency of the production of other biofuels. (authors)
[en] Highlights: • The marginal land narrative has been used to select biofuel project sites in Africa. • Local communities derived ecosystem services from converted ‘marginal lands’. • The ecosystem services approach offers a better lens to select biofuel sites. • For biofuel projects EIA scope must broaden and exit strategies must be mandatory. - Abstract: The concept of marginal land is often used to justify land availability and inform land allocation for biofuel projects. However, marginal lands can provide other valuable ecosystem services. Using interviews with multiple stakeholders and fieldwork in three collapsed biofuel projects in Ghana, this paper shares perspectives on how the ecosystem service approach (ESA) can offer a better basis for selecting land for biofuel projects. Expert interviews with key stakeholders (e.g. Lands Commission) in biofuel value chains in Ghana highlight the lack of consensus of what constitutes marginal land, with two dominant interpretations coming up; (i) land unsuitable for food production and (ii) land unsuitable for cost-effective agricultural production. Both interpretations however do not reflect the ecosystem services lands provide, as well as the significant cultural values attached to them. Our empirical work shows that many ecosystem services are obtained from the supposedly marginal lands that are neglected from both interpretations, as well as the standard project planning and Environmental Impact Assessment (EIA) processes. We make the case that when compared to the current marginal land narrative, the ESA offers a better lens for understanding local land uses, in managing emerging tradeoffs and providing information for locating biofuel projects. Our findings suggest that expanding the scope of EIAs by integrating elements of the ESA can go a long way towards informing site selection for biofuel investments.
[en] The purpose of this case study is to develop and framework supply chain characteristics and risk mitigation strategies in the context of biodiesel downstream supply chain. This study employs an expert interview-based approach as a qualitative approach with a multi-perspectives view. There are vary strategies among perspectives, such as perspectives of organization and business types, stakeholder types, times and methods. These also shows that business strategy of collaborative, coordinative, and cooperative arise as alternative strategies for each perspective and each level of stakeholder. Those business strategies may apply in a vary operation strategies which linking through an energy security framework element as company’s competitive priorities. The research scope includes only a certain area of the country’s territory and the target company’s supply chain areas of activity. The research method includes only internal stakeholders and experts as respondents and data sources. The level of analysis was only at corporate level in the corporate case study context. The research also targets only a downstream activities of biodiesel supply chain context. The interview-based approach as a qualitative approach faces some subjectivity challenges among respondents. The research result provides some positive implications for business practice, includes how to minimize the impact of supply chain risk on company’s business activities and performance, how supply chain experts and practitioners used risk mitigation practices, how to formulate strategic plans to minimize the impact of supply chain risk and enhance the effectivity and sustainability of the supply chain activities. The implication for business practice was that company’s leaders implemented supply chain risk mitigation strategies that provide positive impacts on the more valuable relationship among supply chain actors and stakeholders. The first, is an activities areas and operation schemes-based of biodiesel supply chain point of view. The second, is a multi-perspectives-based biodiesel supply chain characteristics framework. The third, is an energy security framework-based biodiesel risk mitigation strategies framework.
[en] The use of agricultural waste and straw is a problem that includes economic, environmental and technological aspects that need to be resolved, especially at the local level or in specific business entities. This is made possible due to an interactive model for calculating the economic balance and assessment of impacts of the production and refining of biofuels on the environment. (authors)
[en] Estimates for algal production cost vary widely due to differing assumptions. Differences in assumptions make comparisons between proposed algal production systems difficult. Existing economic analyses have ignored potential capital cost growth and under performance of early generation algal production plants, which impact the preliminary unit cost of algal biofuels, which could affect investment decisions. Therefore the goal of this work was to compare the capital cost growth (ratio of actual to estimated cost), plant performance (ratio of actual performance to design), and unit cost growth factor (the ratio of cost growth to plant performance), of potential algal production pathways. Three production technologies were investigated: (1) open raceway ponds (ORP), (2) tubular photobioreactors (PBR), and (3) systems coupling photobioreactors to open raceway ponds. The greatest cost growth (1.5–1.8) was estimated for PBR systems, while the lowest cost growth (1.2–1.4) was estimated for the ORP systems and coupled systems. Plant performance was estimated to range from 13% to 40% of nameplate capacity. These results imply that unit cost growth for algal biofuels could range from 3 to 14 times current predictions, and illustrates large hurdles facing algal biofuels technologies that have yet to be implemented at scale. - Highlights: ► Predictions of cost growth for algal biofuel systems were 1.2–1.8 times the estimate. ► Predictions of plant performance were less than 50% of projected output. ► Systems using photobioreactors greatest cost growth and lowest plant performance.