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[en] Recent failures of renewable energy plants have raised concerns regarding government's role in providing credit subsidies and have harmed the long-run development of renewable energy. The major reason for these failures lies in government loan appraisers not having a model that addresses these root causes and instead relying on traditional net present value (NPV) analysis. What is required is a model representing entrepreneurs' investment decision processes when faced with uncertainty, irreversibility, and flexibility that characterize renewable energy investments. The aim is to develop such a model with a real options analysis (ROA) criterion as the foundation. A case study comparing NPV with ROA decisions for 50 and 100 million gallon ethanol plants is used as a basis for future development of a template government loan appraisers can use for evaluating the feasibility of renewable energy investments. - Highlights: ► The role net present value (NPV) analysis is investigated in failed ethanol plants. ► NPV optimal entry and exit margins are compared to real options approach (ROA). ► The entry–exit margin gap is smaller under the NPV than it is under the ROA. ► Government policymakers employing NPV tend to react aggressively to margin stimuli.
[en] Many Saskatchewan communities are interested in the potential benefits of establishing an ethanol production facility. A guide is presented to outline areas that communities should consider when contemplating the development of an ethanol production facility. Political issues affecting the ethanol industry are discussed including environmental impacts, United States legislation, Canadian legislation, and government incentives. Key success factors in starting a business, project management, marketing, financing, production, physical requirements, and licensing and regulation are considered. Factors which must be taken into consideration by the project manager and team include markets for ethanol and co-products, competent business management staff, equity partners for financing, production and co-product utilization technologies, integration with another facility such as a feedlot or gluten plant, use of outside consultants, and feedstock, water, energy, labour, environmental and site size requirements. 2 figs., 2 tabs
[en] The DOE is in the process of developing technologies for converting plant matter other than feed stock, e.g., corn stover, into biofuels. The goal of this research project was to determine what the farming community thinks of ethanol as a fuel source, and specifically what they think of bioethanol produced from corn stover. This project also assessed the image of the DOE and the biofuels program and determined the perceived barriers to ethanol-from-stover production
[en] One of the important compounds that were used in the structural ceramic is aluminum. During the last years, a variety of synthesis methods have been developed to obtain raw materials with suitable characteristics in terms of the particle composition, size and shape. The controlled precipitation method (CPM) allows reaching these demands and with this method it is possible to control the synthesis one so as to guarantee characteristics of ceramic powder. One stage of the CPM is the formation of the intermediate complexes of cation whose oxide is necessary. In this work the effect of the concentration and the solvent of wash during this process are indicated. For this study we used potentiometric titration to follow the advancement of the process. We utilized XRD and tem to characterize the solid phase present in the system
[en] Seaweed liquid waste (SLW) from a non-conventional seaweed (Gracilaria sp.) drying process where the seaweed is ruptured and filter-squeezed has been investigated. The liquid contains proteins and minerals which potentially pollute the environment if it is not been properly treated. For that reason, this paper deals with study on the feasibility of SLW utilization as a feedstock for bio ethanol production. The fermentation of bio ethanol production was carried out by Saccharomyces cerevisiae in which ethanol produced was measured by gas chromatography. In order to increase its fermentable sugar content, the SLW was treated with dilute acid. Center composite design of response surface methodology (RSM) had been used to optimize the sugar content by varying the parameters involved in the dilute acid pretreatment conditions. These are sulphuric acid concentration (M), temperature (degree Celsius) and seaweed waste concentration (g/ ml). It was obtained that the R"2 value reached 0.97 indicating that the model is acceptable. The three parameters showed p-value less than 0.05 suggesting their significance interactions. The optimization resulted 25 times improvement of reducing sugar concentration. The reducing sugar resulting from the optimized pretreatment was later used as fermentation medium to produce ethanol up to 123.197 mg/ l. (author)
[en] Pseudo-first-order rate constants (k_o_b_s_d) have been measured for nucleophilic substitution reactions of 2-pyridyl benzoate 5 with alkali metal ethoxides (EtOM, M = Li, Na, K) in anhydrous ethanol. The plots of k_o_b_s_d vs. [EtOM]_.deg. are curved upwardly but linear in the excess presence of 18-crown-6-ether (18C6) with significant decreased k_o_b_s_d values in the reaction with EtOK. The k_o_b_s_d value for the reaction of 5 with a given EtONa concentration decreases steeply upon addition of 15-crown-5-ether (15C5) to the reaction medium up to ca. [15C5]/[EtONa]_.deg. = 1, and remains nearly constant thereafter, indicating that M"+ ions catalyze the reaction in the absence of the complexing agents. Dissection k_o_b_s_d into k_E_t_O. and k_E_t_O_M, i.e., the second-order rate constants for the reaction with the dissociated EtO"- and the ion-paired EtOM, respectively has revealed that ion-paired EtOM is 3.2 - 4.6 times more reactive than dissociated EtO"-. It has been concluded that M"+ ions increase the electrophilicity of the reaction center through a 6-membered cyclic transition state. This idea has been examined from the corresponding reactions of 4-pyridyl benzoate 6, which cannot form such a 6-membered cyclic transition state
[en] The results of fundamental and applied studies in the field of electrocatalysis of anodic oxidation of ethanol in fuel cells are considered. Features of the mechanism of ethanol electrooxidation are discussed as well as the structure and electrochemical properties of the most widely used catalysts of this process. The prospects of further studies of direct ethanol fuel cells with alkaline and acidic electrolytes are outlined. The bibliography includes 166 references
[en] The new national as well as international energy context demands revision of the Brazilian Alcohol Program. This revision should aim at the preservation of alcohol as an energy source while reducing subsidies. To this end a moratorium on new distilleries should be enforced till the middle of the next decade, accompanied by a policy focusing on cost reductions and improvements in productivity aimed at making alcohol competitive in the middle term, as well as a motor fuel policy which acts on demand and makes this moratorium viable while preserving the existing production structure. Concrete mechanisms to implement such a policy are proposed which segment the market for new vehicles and preserve the stability of alcohol and gasoline markets for existing vehicles. The effects of this policy were analyzed through simulation of 7 scenarios through the year 2005, which showed its feasibility; the continuation of the present policy, on the other hand, implies heavy additional subsidies. (author)
[en] The energy efficiency of a direct ethanol fuel cell (DEFC) is directly proportional to the average number of electrons released per ethanol molecule (n-value) at the anode. An approach to measuring n-values in DEFC hardware is presented, validated for the oxidation of methanol, and shown to provide n-values for ethanol oxidation that are consistent with trends and estimates from full product analysis. The method is based on quantitative oxidation of fuel that crosses through the membrane to avoid the errors that would otherwise result from crossover. It will be useful for rapid screening of catalysts, and allows performances (polarization curves) and n-values to be determined simultaneously under well controlled transport conditions.