This paper critically analyzes the implementation of compressed natural gas and the ways in which it creates discourse in urban Bolivia. The rapidly developing nation is keen on making ubiquitous use of compressed natural gas a reality by issuing subsidies, citing increased mobility, savings, and environmental stewardship as the primary motives. Currently, eight out of every 10 public vehicles in Bolivia are powered by compressed natural gas. Through semi-structured interviews, questionnaires and secondary data collection, this paper elucidates the transitional process of building a natural gas-based transport network through discursive governance. This work draws on the critical discourse analysis literature to dissect disaggregated modal preference data, government documents, and news articles collected in Santa Cruz, Latin America's second fastest growing city. Moreover, this paper identifies and examines the ways in which the counter-discourse impacts the transformation of the country’s energy matrix. Results show that Bolivian automobile owners are reluctant to convert their automobiles, despite reduced transportation costs, stating that minimal compressed natural gas infrastructure exists outside of urban areas, and the conversion damages their vehicles’ motor. Additionally, the research reveals that automobile owners are currently the main beneficiaries, though respondents who do not posses an automobile speak more favorably of natural gas. Finally, this research illustrates that the compressed natural gas-oriented policies encourage personal automobile use that continues to drive socio-spatial segregation of Santa Cruz’s residents. Thus, the compressed natural gas discourse helps shape the urban landscape by persuading the public to consume domestically extracted and manufactured natural gas.

<p>This paper aims to examine how the driving forces of the Swedish CNG market have impacted OKQ8’s strategies. This has been conducted through the four drivers’ coercive-, market-, resource- and social drivers. The papers conclusion is that all drivers impact on OKQ8’s strategy but that coercive drivers have the most significant impact on the CNG market and OKQ8’s strategy. OKQ8’s decision to establish a cooperation together with E.ON was smart decision since they minimized their own ambiguity in this market that depends on governmental policies and incentives.</p>

This paper aims to examine how the driving forces of the Swedish CNG market have impacted OKQ8’s strategies. This has been conducted through the four drivers’ coercive-, market-, resource- and social drivers. The papers conclusion is that all drivers impact on OKQ8’s strategy but that coercive drivers have the most significant impact on the CNG market and OKQ8’s strategy. OKQ8’s decision to establish a cooperation together with E.ON was smart decision since they minimized their own ambiguity in this market that depends on governmental policies and incentives.

O tema do presente estudo consiste na análise da demanda do mercado de taxistas de Curitiba frente à possibilidade de utilização de um combustível alternativo menos oneroso e poluente: o Gás Natural Veicular – GNV. O objetivo principal deste trabalho foi de analisar o mercado atual do GNV entre os taxistas de Curitiba, verificando a possibilidade de ampliar do uso do GNV por esta frota através de uma pesquisa de mercado. Os dados da pesquisa servirão de subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para tanto, realizou-se uma pesquisa de satisfação para levantar os fatores determinantes para a tomada de decisão dos taxistas de Curitiba de utilizarem ou não um combustível alternativo menos oneroso e poluente como o Gás Natural Veicular – GNV. O estudo visou obter a percepção dos taxistas de Curitiba. Com base nos resultados da pesquisa foi possível estabelecer subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para realização da pesquisa, utilizou-se uma pesquisa exploratória, com entrevistas individuais da cúpula das organizações que trabalham com o Gás Natural, prospectando novos projetos para o futuro e as perspectivas de evolução do mercado de GNV em Curitiba, a qual forneceu subsídios para a pesquisa quantitativa junto aos taxistas da cidade de Curitiba. Constatou-se que somente 36% do público estudado é usuário de gás natural veicular, mas entre os não usuários, 82% já pensou em instalar o kit gás. As principais razões pelas quais os taxistas pesquisados não utilizam o GNV são a perda de espaço no porta-malas e a perda de potência do veículo. Entre os taxistas que utilizam o GNV, no que tange aos atributos relacionados à rede de distribuição, a maior insatisfação refere-se à localização dos postos e a maior satisfação às eventuais filas para abastecimento. Nesses mesmos atributos o que obteve maior índice de importância foi justamente a localização dos postos. Entre os atributos relacionados ao produto, o maior índice de satisfação foi o nível de poluição ambiental e a maior insatisfação espaço para armazenamento, sendo o desempenho do veículo considerado o mais importante. Quanto aos atributos relacionados aos equipamentos, verificou-se a segurança com o maior índice de satisfação e de importância. / The research was based on the following questions: What are the determinant factors for the taxi drivers’ decision on whether or not using a fuel that is less costly and polluting, such as the Compressed natural gas – CNG. The subject of this study consists of the analysis of the demand of the taxi drivers market towards the possibility of utilizing a less costly and polluting alternative fuel: the Compresses Natural Gas – CNG. The main objective of this paper was to analyze the current market of the taxi drivers of Curitiba, verifying the possibility of a unanimous use of the CNG by this fleet through market research. The data of the research will serve as subsidies for marketing campaigns directed to the accelerated increase of the utilization of this technology. For this reason a satisfaction survey was done to find the determinant factors for the decision of the taxi drivers of Curitiba to use or not a less costly and polluting alternative fuel such as the Compressed Natural Gas – CNG. The study aimed to get the feeling of the taxi drivers of Curitiba. Based on the results of the survey it was possible to establish subsidies for marketing campaigns for the accelerated increase of use of this technology. We used an exploratory research, with individual interviews of the heads of the organizations that work with the Compressed Natural Gas, trying to find out what their projects for the future are and the perspectives for the evolution of the CNG in Curitiba. This supplied subsidies for the quantitative research with the taxi drivers of Curitiba. We found out that only 36% of the segment use the compressed natural gas. Among the nonusers, 82% has already considered installing the gas kit. The main reasons for the taxi drivers not using the CNG are the loss of trunk space and of the power of the vehicle. Among the taxi drivers who use the CNG, in terms of the distribution net, the biggest complaint is about the localization of the service stations and the biggest satisfaction refers to the eventual fueling lines. Among these attributes, the one that obtained the highest rate of importance was the localization of the service stations. Among the attributes related to the product, the highest index of satisfaction was the level of environmental pollution, and the biggest complaint was the storage space, with the performance of the vehicle mentioned as the most important. As for the attributes related to the equipment, safety was the item with the highest index of satisfaction and importance.

O tema do presente estudo consiste na análise da demanda do mercado de taxistas de Curitiba frente à possibilidade de utilização de um combustível alternativo menos oneroso e poluente: o Gás Natural Veicular – GNV. O objetivo principal deste trabalho foi de analisar o mercado atual do GNV entre os taxistas de Curitiba, verificando a possibilidade de ampliar do uso do GNV por esta frota através de uma pesquisa de mercado. Os dados da pesquisa servirão de subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para tanto, realizou-se uma pesquisa de satisfação para levantar os fatores determinantes para a tomada de decisão dos taxistas de Curitiba de utilizarem ou não um combustível alternativo menos oneroso e poluente como o Gás Natural Veicular – GNV. O estudo visou obter a percepção dos taxistas de Curitiba. Com base nos resultados da pesquisa foi possível estabelecer subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para realização da pesquisa, utilizou-se uma pesquisa exploratória, com entrevistas individuais da cúpula das organizações que trabalham com o Gás Natural, prospectando novos projetos para o futuro e as perspectivas de evolução do mercado de GNV em Curitiba, a qual forneceu subsídios para a pesquisa quantitativa junto aos taxistas da cidade de Curitiba. Constatou-se que somente 36% do público estudado é usuário de gás natural veicular, mas entre os não usuários, 82% já pensou em instalar o kit gás. As principais razões pelas quais os taxistas pesquisados não utilizam o GNV são a perda de espaço no porta-malas e a perda de potência do veículo. Entre os taxistas que utilizam o GNV, no que tange aos atributos relacionados à rede de distribuição, a maior insatisfação refere-se à localização dos postos e a maior satisfação às eventuais filas para abastecimento. Nesses mesmos atributos o que obteve maior índice de importância foi justamente a localização dos postos. Entre os atributos relacionados ao produto, o maior índice de satisfação foi o nível de poluição ambiental e a maior insatisfação espaço para armazenamento, sendo o desempenho do veículo considerado o mais importante. Quanto aos atributos relacionados aos equipamentos, verificou-se a segurança com o maior índice de satisfação e de importância. / The research was based on the following questions: What are the determinant factors for the taxi drivers’ decision on whether or not using a fuel that is less costly and polluting, such as the Compressed natural gas – CNG. The subject of this study consists of the analysis of the demand of the taxi drivers market towards the possibility of utilizing a less costly and polluting alternative fuel: the Compresses Natural Gas – CNG. The main objective of this paper was to analyze the current market of the taxi drivers of Curitiba, verifying the possibility of a unanimous use of the CNG by this fleet through market research. The data of the research will serve as subsidies for marketing campaigns directed to the accelerated increase of the utilization of this technology. For this reason a satisfaction survey was done to find the determinant factors for the decision of the taxi drivers of Curitiba to use or not a less costly and polluting alternative fuel such as the Compressed Natural Gas – CNG. The study aimed to get the feeling of the taxi drivers of Curitiba. Based on the results of the survey it was possible to establish subsidies for marketing campaigns for the accelerated increase of use of this technology. We used an exploratory research, with individual interviews of the heads of the organizations that work with the Compressed Natural Gas, trying to find out what their projects for the future are and the perspectives for the evolution of the CNG in Curitiba. This supplied subsidies for the quantitative research with the taxi drivers of Curitiba. We found out that only 36% of the segment use the compressed natural gas. Among the nonusers, 82% has already considered installing the gas kit. The main reasons for the taxi drivers not using the CNG are the loss of trunk space and of the power of the vehicle. Among the taxi drivers who use the CNG, in terms of the distribution net, the biggest complaint is about the localization of the service stations and the biggest satisfaction refers to the eventual fueling lines. Among these attributes, the one that obtained the highest rate of importance was the localization of the service stations. Among the attributes related to the product, the highest index of satisfaction was the level of environmental pollution, and the biggest complaint was the storage space, with the performance of the vehicle mentioned as the most important. As for the attributes related to the equipment, safety was the item with the highest index of satisfaction and importance.

O tema do presente estudo consiste na análise da demanda do mercado de taxistas de Curitiba frente à possibilidade de utilização de um combustível alternativo menos oneroso e poluente: o Gás Natural Veicular – GNV. O objetivo principal deste trabalho foi de analisar o mercado atual do GNV entre os taxistas de Curitiba, verificando a possibilidade de ampliar do uso do GNV por esta frota através de uma pesquisa de mercado. Os dados da pesquisa servirão de subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para tanto, realizou-se uma pesquisa de satisfação para levantar os fatores determinantes para a tomada de decisão dos taxistas de Curitiba de utilizarem ou não um combustível alternativo menos oneroso e poluente como o Gás Natural Veicular – GNV. O estudo visou obter a percepção dos taxistas de Curitiba. Com base nos resultados da pesquisa foi possível estabelecer subsídios para campanhas de marketing orientadas à ampliação acelerada do uso desta tecnologia. Para realização da pesquisa, utilizou-se uma pesquisa exploratória, com entrevistas individuais da cúpula das organizações que trabalham com o Gás Natural, prospectando novos projetos para o futuro e as perspectivas de evolução do mercado de GNV em Curitiba, a qual forneceu subsídios para a pesquisa quantitativa junto aos taxistas da cidade de Curitiba. Constatou-se que somente 36% do público estudado é usuário de gás natural veicular, mas entre os não usuários, 82% já pensou em instalar o kit gás. As principais razões pelas quais os taxistas pesquisados não utilizam o GNV são a perda de espaço no porta-malas e a perda de potência do veículo. Entre os taxistas que utilizam o GNV, no que tange aos atributos relacionados à rede de distribuição, a maior insatisfação refere-se à localização dos postos e a maior satisfação às eventuais filas para abastecimento. Nesses mesmos atributos o que obteve maior índice de importância foi justamente a localização dos postos. Entre os atributos relacionados ao produto, o maior índice de satisfação foi o nível de poluição ambiental e a maior insatisfação espaço para armazenamento, sendo o desempenho do veículo considerado o mais importante. Quanto aos atributos relacionados aos equipamentos, verificou-se a segurança com o maior índice de satisfação e de importância. / The research was based on the following questions: What are the determinant factors for the taxi drivers’ decision on whether or not using a fuel that is less costly and polluting, such as the Compressed natural gas – CNG. The subject of this study consists of the analysis of the demand of the taxi drivers market towards the possibility of utilizing a less costly and polluting alternative fuel: the Compresses Natural Gas – CNG. The main objective of this paper was to analyze the current market of the taxi drivers of Curitiba, verifying the possibility of a unanimous use of the CNG by this fleet through market research. The data of the research will serve as subsidies for marketing campaigns directed to the accelerated increase of the utilization of this technology. For this reason a satisfaction survey was done to find the determinant factors for the decision of the taxi drivers of Curitiba to use or not a less costly and polluting alternative fuel such as the Compressed Natural Gas – CNG. The study aimed to get the feeling of the taxi drivers of Curitiba. Based on the results of the survey it was possible to establish subsidies for marketing campaigns for the accelerated increase of use of this technology. We used an exploratory research, with individual interviews of the heads of the organizations that work with the Compressed Natural Gas, trying to find out what their projects for the future are and the perspectives for the evolution of the CNG in Curitiba. This supplied subsidies for the quantitative research with the taxi drivers of Curitiba. We found out that only 36% of the segment use the compressed natural gas. Among the nonusers, 82% has already considered installing the gas kit. The main reasons for the taxi drivers not using the CNG are the loss of trunk space and of the power of the vehicle. Among the taxi drivers who use the CNG, in terms of the distribution net, the biggest complaint is about the localization of the service stations and the biggest satisfaction refers to the eventual fueling lines. Among these attributes, the one that obtained the highest rate of importance was the localization of the service stations. Among the attributes related to the product, the highest index of satisfaction was the level of environmental pollution, and the biggest complaint was the storage space, with the performance of the vehicle mentioned as the most important. As for the attributes related to the equipment, safety was the item with the highest index of satisfaction and importance.

No description available.

In-cylinder fuel-air mixing in a compressed natural gas (CNG)-fuelled, single-cylinder, spark-ignited engine is analysed using a transient three-dimensional computational fluid dynamic model built and run using STAR-CD, a commercial CFD software. This work is motivated by the need for strategies to achieve improved performance in engines utilizing gaseous fuels such as CNG. The transient in-cylinder fuel-air mixing is evaluated for a port gas injection fuelling system and compared with that of conventional gas carburetor system. In this work pure methane is used as gaseous fuel for all the computational studies. It is observed that compared to the premixed gas carburetor system, a substantial level of in-cylinder stratification can be achieved with the port gas injection system. The difference of more than 20% in mass fraction between the rich and lean zones in the combustion chamber is observed for the port gas injection system compared to less than 1% for the conventional premixed system. The phenomenon of stratification observed is very close to the “barrel stratification” mode. A detailed parametric study is undertaken to understand the effect of various injection parameters such as injection location, injection orientation, start of injection, duration of injection and rate of injection. Furthermore, the optimum injection timing is evaluated for various load-speed conditions of the engine. It is also observed that the level of stratification is highest at 50% engine load with a reduced level at 100% load. For low engine loads, the level of stratification is observed to be very low. To analyse the effect of stratification on engine performance, the in-cylinder combustion is modeled using the extended coherent flame model(ECFM). For simulating the ignition process, the arc and kernel tracking ignition model(AKTIM) is used. The combustion model is first validated with measured in-cylinder pressure data and other derived quantities such as heat release rate and mass burn fraction. It is observed that there is a good agreement between measured and simulated values. Subsequently, this model is use to simulate both premixed and stratified cases. It is observed that there is a marginal improvement in terms of overall engine efficiency when the stoichiometric premixed case is compared with the lean stratified condition. However, a major improvement in performance is observed when the lean stratified case is compared with lean premixed condition. The stratified case shows a faster heat release rate which could potentially translate to lower cycle-to-cycle variations in actual engine operation. Also, the stratified cases show as much as 20% lower in-cylinder NOx emissions when compared with the conventional premixed case at the same engine load and speed, underscoring the potential of in-cylinder stratification to achieve improved performance and lower NOx emissions.

No description available.

É cada vez maior a busca por fontes de energia alternativas com vistas à substituição dos derivados do Petróleo, em especial após a crise da década de 70. A indústria automotiva segue a mesma tendência, buscando alternativas viáveis frente à incerteza do tempo e quantidade que ainda resta de estoque de combustíveis fósseis líquidos. Além do Álcool como meio de substituição ao Diesel e a Gasolina, a utilização de GNV - Gás Natural Veicular - está entre as tecnologias atualmente consideradas viáveis e eficientes. Segundo a ANP - Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (2006), o Brasil possui reservas comprovadas de 306,4 x 109 m3 de Gás Natural, quantidade estimada para abastecer o mercado nacional, no cenário mais pessimista, pelos próximos cinqüenta anos. A associação desses fatores resulta na busca do consumidor brasileiro pela redução dos gastos cada vez maiores com combustível e no aumento da demanda por veículos movidos a Gás Natural. Apesar da notória demanda de mercado, atualmente existem no Brasil poucas opções de veículos leves com Sistemas de Conversão originalmente instalados pelas montadoras e com manutenção da garantia de fábrica. A falta de opções de oferta abre espaço para o grande aumento do número de oficinas de conversão, freqüentemente ignorando aspectos técnicos e de legislação de conversão, na intenção de apenas obterem lucros com o aumento de demanda. Mais do que pretensiosas conclusões definitivas, o presente trabalho tem como objetivo oferecer uma pequena contribuição à indústria e à sociedade, através da análise da viabilidade técnica, econômica, ambiental e mercadológica da instalação original de fábrica de Sistema de Conversão para uso de Gás Natural em veículos leves movidos a Gasolina e / ou Álcool, frente ao atual mercado de veículos convertidos e ao aumento da demanda por fontes de energia alternativa. / The search for alternative energy sources aiming the substitution of derivate Oil products is each time higher, especially after the 70s Petroleum crisis. The automotive industry follows this trend too, looking for possible alternatives in face of the uncertainness of time and quantity available stocks of liquid fossil fuels. Besides the Ethanol as a way of Gasohol and Diesel substitution, the CNG - Compressed Natural Gas - use is nowadays considered one of the most possible and efficient technologies. According to the ANP - National Petroleum, Natural Gas and Biofuel Agency (2006), Brazil owns 306,4 x 109 m3 of Compressed Natural Gas proved reserves, which are considered enough to supply the national market, in the worst case, for the next fifty years. The conjunction of these issues results in the Brazilian customers search for the each higher fuel expenses reduction and the raise of Compressed Natural Gas impelled vehicles demand. Despite the notorious market demand, there are nowadays on Brazil only a few options of light vehicles with Conversion System originally installed by automotive assemblers and warrantys maintenance. This lack of supply options creates a large field to the raise in the quantity of conversion workshops, frequently ignoring the technical aspects and the conversion legislation only with intent of achieving profit with the demand raise. More than pretentious definitive conclusions, the present work aims to offer a small contribution to the industry and society through the technical, economical, environmental and merchandizing practicability analysis of original assemblers installation of Conversion System to the use of Compressed Natural Gas in Gasohol and / or Ethanol impelled light vehicles, in face of the actual converted vehicles market and the demand raise for alternative energy sources.