Este trabalho aborda a problemática do transporte de carga frigorificada, sob a ótica da eficiência energética da unidade frigorífica. São propostas alternativas para conservação de alimentos, independentemente do frio. Embora incapazes de substituir totalmente o frio, podem ser uma alternativa em vários casos. É analisada a tecnologia de frigorificação atualmente empregada, enfocando custos do sistema, eficiência energética e efeitos da atual tecnologia sobre o meio ambiente. É desenvolvido o projeto preliminar de uma unidade de refrigeração por absorção, que é analisado comparativamente com as unidades por compressão a vapor. Este estudo mostra que o sistema de refrigeração por absorção pode ser viável em muitas aplicações onde não se dispõe de energia térmica ou mecânica. / This study analyses refrigerated freigth transportation, under the scope of refrigeration energy effeciency. There are several alternatives for food conservation, independently of refrigeration. These existing technologies are not capable of completely replacing refrigeration, but they could be utilized in many cases. The refrigeration techonology currently used is analysed, focusing on system costs, energy efficiency and environmental impacts. A preliminary design of an absoption system was done and an analysis was performed comparating it with the compression units. Conclusive analysis of the system will depend of the evaluation of the experimental unit. This study shows that refrigeration by absortion could be viable in various aplications where no electricity or mechanical energy are available.

A próxima década oferece ao mundo um verdadeiro desafio em relação à conservação de várias formas de energia. Para isso, torna-se necessário a cooperação de vários agentes envolvidos no desenvolvimento de um mercado de eficiência energética, tais como, o governo, a agência reguladora, as empresas geradoras de eletricidade, os vendedores de equipamentos, as empresas distribuidoras de eletricidade e os consumidores. O setor residencial da cidade de Cochabamba é responsável por 44% do consumo de energia elétrica, abrange 86.88% dos consumidores do sistema elétrico de Cochabamba e tem uma taxa média de crescimento da demanda de energia elétrica de 8.S% ao ano. Este setor é muito importante e apresenta um grande potencial de conservação de energia elétrica nos três usos finais que apresentam o maior consumo (79%) em Cochabamba: refrigeração, iluminação e aquecimento da água. No presente trabalho, realiza-se a caracterização da demanda de eletricidade por usos finais em um estudo-piloto, com uma metodologia desenvolvida a partir da realização de uma pesquisa de hábitos de consumo e posse de eletrodomésticos. São analisadas as oportunidades que apresentam-se atualmente na Bolívia para viabilizar o desenvolvimento do mercado de tecnologia ecientes em razão da recente restruturação do setor elétrico boliviano que oferece sinais econômicos de mercado para atingir a eficiência econômica no fornecimento elétrico a custo mínimo. Também são analisadas as barreiras que existem na Bolívia para a introdução de tecnologias eficientes no mercado e propõem-se diversas condições que devem estabelecer-se para desenvolver um mercado de eciência energética. Analisam-se as condições operacionais associando ações do agente regulador, dos vendedores de equipamentos das empresas de energia elétrica e dos consumidores para a aceleração da penetração de tecnologias eficientes de uso final disponíveis em outros mercados. / The next decade introduces a real challenge for energy conservation. This will require the cooperation of many actors involved in an energy efficiency market as the government, the regulatory body, the electric power generating companies, the equipment vendors, the electricity distribution companies and the consumers. In the city of Cochabamba, the residential sector uses 44 percent of the total electrical energy consumption and corresponds to 86,88 percent of the electricity users. As the average demand growth rate is 8.5 percent per year, the residential sector has a large potential for electricity conservation because the three most important end-uses (lighting, refrigeration and water heating) consume 79 percent of total electricity in Cochabamba. The present work assesses the electricity end-uses through a pilot study, applying a methodology using a survey on electrical appliances and consumption. The opportunities for development of an energy efficient tecnologies market in Bolivia are also analized as the recent electricy reform is providing economic signals to achieve economic efficiency at the least-cost electricity supply. The barriers to the introduction of energy efficient tecnologies in Bolivia are also considered with the required conditions for development of a market for energy efficiency. For that purpose, the operational conditions includes the role of the regulatory agency, the equipment vendors, the electricity companies and the consumers in order to accelerate the introduction of efficient tecnologies for end uses available in other markets.

Improving the energy efficiency of our existing building stock is attainable by upgrading the building envelope through carrying out various retrofit measures. The objective of this thesis is to evaluate the life-cycle cost implications of energy retrofits for existing buildings. Measures examined include improving insulation and air-tightness with overcladding strategies. The life-cycle costs of the upgrades are determined for an existing building and compared with model energy performance. A life-cycle cost evaluation for the building envelope upgrades is provided, together with the payback period and the projected return on investment (ROI) for two energy escalation rate scenarios. A costbenefit matrix for various over-cladding strategies is provided to facilitate the evaluation of each option. Further, this thesis presents a simplified ROI algorithm to enable owners, architects and engineers to evaluate the cost-benefit of their building envelope retrofit options.

Improving the energy efficiency of our existing building stock is attainable by upgrading the building envelope through carrying out various retrofit measures. The objective of this thesis is to evaluate the life-cycle cost implications of energy retrofits for existing buildings. Measures examined include improving insulation and air-tightness with overcladding strategies. The life-cycle costs of the upgrades are determined for an existing building and compared with model energy performance. A life-cycle cost evaluation for the building envelope upgrades is provided, together with the payback period and the projected return on investment (ROI) for two energy escalation rate scenarios. A costbenefit matrix for various over-cladding strategies is provided to facilitate the evaluation of each option. Further, this thesis presents a simplified ROI algorithm to enable owners, architects and engineers to evaluate the cost-benefit of their building envelope retrofit options.

Gerdau Manitoba Mill (Gerdau) at Selkirk, Manitoba is one of the biggest energy consumers in the province of Manitoba. This research analysis undertaken at Gerdau evaluated opportunities for energy efficiency, including the following six areas: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters, 5) Oxyfuel combustion, and 6) “tap to tap time” control in the eccentric bottom tapping (EBT) furnace in the melt shop. As part of this research, end-user distribution was analyzed and energy losses were assessed. An end-use analysis found that the melt shop that includes the EBT furnace is the biggest consumer of electricity consumption (kWh) and electric demand (kVa), which accounted for 68.7% and 73.6 % respectively. The 2010 delay time in the power-off time of EBT furnace at Gerdau was found to be 762.3 hr/yr. Further research to analyze the cause of each downtime at Gerdau is recommended to determine how these unplanned downtime can be reduced in the EBT furnace. The reheat furnace is the biggest natural gas consumer at Gerdau with 437,563 MCF in 2010. Flue gas losses from the reheat furnace are the biggest energy losses in the gross heat distribution with 26,874,657 Btu/hr. Energy losses from hearth and roof by heat transmission are the biggest energy losses in the net heat distribution during operation, which accounted for 8.9%. The average thermal efficiency in the reheat furnace at Gerdau is 58.9% ± 3.6%. Compared to peak capacity, idle and partial operations of the reheat furnace and idling were found to be less efficient. The opportunities that are considered feasible and recommended to Gerdau are: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters. These are both good for the environment, reducing fuel use and emissions and providing a good payback period and annual savings. Many opportunities are available for reducing energy as provided in Table A, which shows emissions reductions, costs, energy savings and payback. Oxyfuel combustion is not deemed feasible without considering productivity improvement as oxygen cost is more than natural gas saving. A number of incentive programs, including those from Manitoba Hydro, are applicable to Gerdau. However, a number of barriers to accessing these, particularly as regards tax incentive programs, should be explored to see if these barriers can be overcome.

Gerdau Manitoba Mill (Gerdau) at Selkirk, Manitoba is one of the biggest energy consumers in the province of Manitoba. This research analysis undertaken at Gerdau evaluated opportunities for energy efficiency, including the following six areas: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters, 5) Oxyfuel combustion, and 6) “tap to tap time” control in the eccentric bottom tapping (EBT) furnace in the melt shop. As part of this research, end-user distribution was analyzed and energy losses were assessed. An end-use analysis found that the melt shop that includes the EBT furnace is the biggest consumer of electricity consumption (kWh) and electric demand (kVa), which accounted for 68.7% and 73.6 % respectively. The 2010 delay time in the power-off time of EBT furnace at Gerdau was found to be 762.3 hr/yr. Further research to analyze the cause of each downtime at Gerdau is recommended to determine how these unplanned downtime can be reduced in the EBT furnace. The reheat furnace is the biggest natural gas consumer at Gerdau with 437,563 MCF in 2010. Flue gas losses from the reheat furnace are the biggest energy losses in the gross heat distribution with 26,874,657 Btu/hr. Energy losses from hearth and roof by heat transmission are the biggest energy losses in the net heat distribution during operation, which accounted for 8.9%. The average thermal efficiency in the reheat furnace at Gerdau is 58.9% ± 3.6%. Compared to peak capacity, idle and partial operations of the reheat furnace and idling were found to be less efficient. The opportunities that are considered feasible and recommended to Gerdau are: 1) recovering waste heat to preheat billets, 2) upgrading the charge end in the reheat furnace, 3) recovering waste heat to preheat combustion air in the ladle preheater, 4) replacing direct-fired natural gas heaters with indirect-fired natural gas heaters. These are both good for the environment, reducing fuel use and emissions and providing a good payback period and annual savings. Many opportunities are available for reducing energy as provided in Table A, which shows emissions reductions, costs, energy savings and payback. Oxyfuel combustion is not deemed feasible without considering productivity improvement as oxygen cost is more than natural gas saving. A number of incentive programs, including those from Manitoba Hydro, are applicable to Gerdau. However, a number of barriers to accessing these, particularly as regards tax incentive programs, should be explored to see if these barriers can be overcome.

Este trabalho aborda a problemática do transporte de carga frigorificada, sob a ótica da eficiência energética da unidade frigorífica. São propostas alternativas para conservação de alimentos, independentemente do frio. Embora incapazes de substituir totalmente o frio, podem ser uma alternativa em vários casos. É analisada a tecnologia de frigorificação atualmente empregada, enfocando custos do sistema, eficiência energética e efeitos da atual tecnologia sobre o meio ambiente. É desenvolvido o projeto preliminar de uma unidade de refrigeração por absorção, que é analisado comparativamente com as unidades por compressão a vapor. Este estudo mostra que o sistema de refrigeração por absorção pode ser viável em muitas aplicações onde não se dispõe de energia térmica ou mecânica. / This study analyses refrigerated freigth transportation, under the scope of refrigeration energy effeciency. There are several alternatives for food conservation, independently of refrigeration. These existing technologies are not capable of completely replacing refrigeration, but they could be utilized in many cases. The refrigeration techonology currently used is analysed, focusing on system costs, energy efficiency and environmental impacts. A preliminary design of an absoption system was done and an analysis was performed comparating it with the compression units. Conclusive analysis of the system will depend of the evaluation of the experimental unit. This study shows that refrigeration by absortion could be viable in various aplications where no electricity or mechanical energy are available.

A próxima década oferece ao mundo um verdadeiro desafio em relação à conservação de várias formas de energia. Para isso, torna-se necessário a cooperação de vários agentes envolvidos no desenvolvimento de um mercado de eficiência energética, tais como, o governo, a agência reguladora, as empresas geradoras de eletricidade, os vendedores de equipamentos, as empresas distribuidoras de eletricidade e os consumidores. O setor residencial da cidade de Cochabamba é responsável por 44% do consumo de energia elétrica, abrange 86.88% dos consumidores do sistema elétrico de Cochabamba e tem uma taxa média de crescimento da demanda de energia elétrica de 8.S% ao ano. Este setor é muito importante e apresenta um grande potencial de conservação de energia elétrica nos três usos finais que apresentam o maior consumo (79%) em Cochabamba: refrigeração, iluminação e aquecimento da água. No presente trabalho, realiza-se a caracterização da demanda de eletricidade por usos finais em um estudo-piloto, com uma metodologia desenvolvida a partir da realização de uma pesquisa de hábitos de consumo e posse de eletrodomésticos. São analisadas as oportunidades que apresentam-se atualmente na Bolívia para viabilizar o desenvolvimento do mercado de tecnologia ecientes em razão da recente restruturação do setor elétrico boliviano que oferece sinais econômicos de mercado para atingir a eficiência econômica no fornecimento elétrico a custo mínimo. Também são analisadas as barreiras que existem na Bolívia para a introdução de tecnologias eficientes no mercado e propõem-se diversas condições que devem estabelecer-se para desenvolver um mercado de eciência energética. Analisam-se as condições operacionais associando ações do agente regulador, dos vendedores de equipamentos das empresas de energia elétrica e dos consumidores para a aceleração da penetração de tecnologias eficientes de uso final disponíveis em outros mercados. / The next decade introduces a real challenge for energy conservation. This will require the cooperation of many actors involved in an energy efficiency market as the government, the regulatory body, the electric power generating companies, the equipment vendors, the electricity distribution companies and the consumers. In the city of Cochabamba, the residential sector uses 44 percent of the total electrical energy consumption and corresponds to 86,88 percent of the electricity users. As the average demand growth rate is 8.5 percent per year, the residential sector has a large potential for electricity conservation because the three most important end-uses (lighting, refrigeration and water heating) consume 79 percent of total electricity in Cochabamba. The present work assesses the electricity end-uses through a pilot study, applying a methodology using a survey on electrical appliances and consumption. The opportunities for development of an energy efficient tecnologies market in Bolivia are also analized as the recent electricy reform is providing economic signals to achieve economic efficiency at the least-cost electricity supply. The barriers to the introduction of energy efficient tecnologies in Bolivia are also considered with the required conditions for development of a market for energy efficiency. For that purpose, the operational conditions includes the role of the regulatory agency, the equipment vendors, the electricity companies and the consumers in order to accelerate the introduction of efficient tecnologies for end uses available in other markets.

No description available.

This thesis is a part of the major EU project EE-Highrise which is a part of the European 7th Framework Research Program (FP7-ENERGY). In order to demonstrate and test new technologies and concepts, a demo building has been constructed in Ljubljana, the capital of Slovenia. The approach during the development of the building has been to consider all its elements with the purpose to increase the energy efficiency and sustainability of the building. Umeå University’s objective is to develop regional specific models of the demo high-rise building. The objective of this thesis is to evaluate whether a simplified model of the high rise building, Eco Silver House, can meet the passive house classifications in four selected cities; Ljubljana, Sibenik, Umeå and Dubai and then to suggest improvements of the models for the different regions. Drawings of the building were provided along with an IFC file for construction of the model in PHPP. The simulation tool used for simulations, PHPP, contained all necessary tools for designing a properly functioning Passive House. By preparing an energy balance, the annual energy demand of the building was calculated based on input related to building characteristics. Results from the simulations have then been compared to the requirements for the German Passive House classification. The performance of the building in Umeå has also be compared to the Swedish passive house standards. Improvements to the climate shell and the ventilation system were after that examined depending on the results. It was shown that it is possible to construct regional specific models that fulfill the passive house requirements in three of four regions. The model achieved passive house standard without any additional energy efficiency measures in Ljubljana and Šibenik while a combination of measures was needed to fulfill all the criteria’s in Umeå. The Swedish requirements used for evaluation of the model in Sweden were easier to fulfill since they have been developed for the cold climate present in Umeå. Since no regional passive house classification was used to evaluate the performance of the model in Dubai the cooling and primary energy demand exceeded the limiting criteria’s. The energy efficiency measure with reduced window area had the greatest impact on heating and cooling demand in all climates. This measure should be included in all future models which also is suggested by parallel studies on similar models of the same building. The only climate where an increased U-value of the external envelope resulted in improved performance of the model was in Šibenik. For all the other climates where a lowered U-value was implemented did the overall performance improve. / EE-Highrise (European 7th Framework Research Program.