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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The cost of passive solar energy

Meyer, John Irving January 1977 (has links)
Thesis. 1977. M.Arch.A.S.--Massachusetts Institute of Technology. Dept. of Architecture. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH. / Includes bibliographical references. / by John I. Meyer, Jr. / M.Arch.A.S.
2

Aspects of the life-cycle energetics of two subspecies of Dunlin Calidris alpina

Al-Mansour, Mansour I. January 2000 (has links)
Dunlin from two breeding populations, C.a.schinzii from Iceland and C.a.alpina from northern Scandinavia, were studied during and after migration through Teesmouth, north-east England, and in captivity. C.a.schinzii winters in north-west Africa and has a much longer migration pathway than C.a.alpina which winters in Britain and around the North Sea. Measurements of Resting metabolic Rate (RMR) were made for the two subspecies of Dunlin in March and November in order to establish the relationship between resting metabolic rate and temperature and hence energy costs of living at different temperatures (20 C - 0 C). Energy costs of living in C.a.alpina were 21% higher than C.a.schinzii. Measurements of Basal Metabolic Rate (BMR) were made for the two subspecies (before, during and after moult) in conjunction with measurements of body compositions using Total Body Electrical Conductivity (TOBEC) in order to estimate the costs of moult. Energy costs of moult were 1692 KJ for alpina and 1016 KJ for schinzii.Energy costs of migration were estimated by measuring the amount of fat laid down before departure by wild Dunlin of the two populations, with the aid of Total Body Electrical Conductivity (TOBEC). Energy costs of migration were estimated as 3489 KJ for alpina, and 5156 KJ for schinzii. Energy costs of egg production and incubation were estimated from other workers’ studies of other (similar) species. Energy costs of egg production were only 220 KJ for the two subspecies whereas the costs of incubation were 1232 KJ and 1143 KJ in alpine and schinzii, respectively. In contrast to the suggestion by Drent and Piersma (1990), I have found that the costs of migration are considerably less than the costs of living. Also the total annual energy cost for those Dunlin wintering in colder areas i.e. C.a.alpina is much higher than for those wintering in tropical regions i.e. C.a.schinzii. Energy costs are not the only factors that affect a bird's lifetime output of young. C.a.alpina uses a different migration strategy to C.a.schinzii but may breed on better breeding grounds, and hence achieve more successful reproduction.
3

Power, capital and energy costs trade-offs in heat exchanger networks

Jegede, Felix Olarewaju January 1990 (has links)
No description available.
4

Fuel poverty in America and possible solutions to address it in the Texas colonias

Hughes, Nicole Elizabeth 24 October 2014 (has links)
Communities across the United States have almost universal access to electricity services. However, there remains a large problem with fuel poverty, where households pay a significant and disproportionate amount of their gross income on energy bills. This is often a factor in those households’ continued poverty. Fuel poverty is especially prevalent in the unincorporated and often overlooked colonias communities in South Texas, near the border with Mexico, which are characterized by a high level of poverty, a large unbanked population that don’t have or are unapproved to have bank accounts, proportionally high energy costs, and substandard housing. There are government programs and charities that assist with bills, but the cycle of fuel poverty will continue without solutions that address the source of the disproportionately high bills: energy inefficiency. Public-private partnerships are needed to sustainably finance energy efficiency improvements and to break the cycle of poverty. One potential solution is the application of microfinance concepts geared solely at home efficiency improvements, where households can build credit while alleviating their home energy bill burden. / text
5

SPECIFICATION ERRORS IN ESTIMATING COST FUNCTIONS: THE CASE OF THE NUCLEAR ELECTRIC GENERATING INDUSTRY.

JORGENSEN, EDWARD JOHN. January 1987 (has links)
This study is an application of production-cost duality theory. Duality theory is reviewed for the competitive and rate-of-return regulated firm. The cost function is developed for the nuclear electric power generating industry of the United States using capital, fuel and labor factor inputs. A comparison is made between the Generalized Box-Cox (GBC) and Fourier Flexible (FF) functional forms. The GBC functional form nests the Generalized Leontief, Generalized Square Root Quadratic and Translog functional forms, and is based upon a second-order Taylor-series expansion. The FF form follows from a Fourier-series expansion in sine and cosine terms using the Sobolev norm as the goodness of fit measure. The Sobolev norm takes into account first and second derivatives. The cost function and two factor shares are estimated as a system of equations using maximum likehood techniques, with Additive Standard Normal and Logistic Normal error distributions. In summary, none of the special cases of the GBC function form are accepted. Homotheticity of the underlying production technology can be rejected for both the GBC and FF forms, leaving only the unrestricted versions supported by the data. Residual analysis indicates a slight improvement in skewness and kurtosis for univariate and multivariate cases when the Logistic Normal distribution is used.
6

Análise dos dispêndios energéticos e econômicos da implantação de eucalipto

Gatin, Edse Amanda Bertalha [UNESP] 09 December 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-09Bitstream added on 2014-06-13T19:52:27Z : No. of bitstreams: 1 gatin_eab_me_botfca.pdf: 941614 bytes, checksum: 312ace0586210286c6b2c4e307c70cba (MD5) / O presente trabalho teve por objetivo analisar e comparar os dispêndios energéticos e econômicos da implantação de eucalipto, região de Botucatu, no município de Itatinga, estado de São Paulo. Comparando-se os gastos energéticos com o econômico, pode haver divergência, segundo seu tipo, fonte e forma, pois a análise energética capta as relações estruturais da produção, e a econômica, situações conjunturais de mercado. Utilizaram-se dados de fontes primárias e secundárias. A construção do itinerário técnico e informações da implantação de eucalipto foram obtidos em pesquisas realizadas em campo, diretamente com os técnicos e responsáveis pela operação. De fontes secundárias foram coletados dados referentes aos salários dos diaristas e tratoristas e os valores de maquinários e implementos agrícolas. A implantação de eucalipto é um conjunto de operações com investimentos em máquinas, consumo de combustível e de lubrificante, insumos e mão-deobra, representando dispêndios energéticos e econômicos. Nesta análise a entrada energética foi classificada e quantificada conforme o seu tipo, energias diretas e energias indiretas, sendo a direta dividida em energia biológica e fóssil e a indireta em energia industrial. A análise econômica foi realizada separando as energias segundo seu tipo, fonte e forma, igualmente a análise energética. Pela análise energética o sistema quantificou um dispêndio de 21.831,76 MJ . ha-1, sendo que os fertilizantes químicos foram os que tiveram maior participação (56,05%). Pela análise econômica os dispêndios da implantação de eucalipto foram de R$ 3.884,18 . ha-1, os fertilizantes participaram deste dispêndio com cerca de 36,48%. Comparando a análise energética com a econômica, verificou-se que a energia direta fóssil tem uma participação na vertente energética de 18,97% e na vertente econômica... / This report aims to analyze and compare economic and energy costs from eucalyptus implementation, Botucatu region, Itatinga town, São Paulo state in Brazil. Comparing the economic costs with the energy costs, there can be differences about type, source and format because the energy analysis gets production structure relation, and the economic checking is related to market movements. It was used in this, data from second and first kind of sources. The building of the technical itinerary and eucalyptus implementation information were obtained from researches made in the field, directly with technicians and people responsible for the operation. From second sources, it was collected data refer to salary of daily and tractor drivers and the also values from agricultural machinery and machinery in general. The implementation of the eucalyptus is a group of operations with investments in machines, fuels use and lubricants, inputs and labor, which brings economic and energy costs. In this analysis the energy was classified and quantified by its own type, direct and indirect energy; so that the direct energy was divided in fossil and biological and the indirect to industrial energy. The economical analysis was done in the same way as the energy. By the economic analysis the system quantified a cost of 21.831,76 MJ. ha-1, in a way that the chemical fertilizers had the biggest role (56,05%). By the economic analysis the cost of the eucalyptus implementation was R$ 3.884,10 . ha-1, the fertilizes were about 36,48%. Comparing those analysis, it was checked that direct energy from fossil has a great role in energetic aspect of 18,97% and in the economic aspect of 5,24%. In a long term this system may have implications in the energetic sustainable view because it depends on non-renewable sources as well as a high cost when using these energies where its value is determined by the market
7

Energy Optimisation of a Building: a Case Study of Ekebyvallen, Uppsala : Profitable investments in a world with rising energy prices

Enarsson, Pär, Hedenmo, Otto, Sillevis Smitt, Dirk-Jan January 2013 (has links)
Energy prices are on the rise, and with it the interest in saving energy. In the housing sector this means that methods for energy optimising buildings, retrofitting, are increasingly important. There are many studies concerning the retrofitting of buildings built before 2000, but less concerning buildings of more recent date. In cooperation with the housing company Uppsalahem, this report explores minor retrofitting solutions for the apartment buildings in Ekebyvallen/Uppsala which were built 2007. The aim was foremost to find solutions for Ekebyvallen but also to assess the possibilities of applying them to a wider range of buildings. A simulation of the energy balance in one of the buildings in Ekebyvallen was performed with the software VIP energy. The simulation together with a field study show weak spots of the energy usage in the buildings and based on these four retrofitting solutions were proposed. The methods; 1) reducing the airflow in the ventilation units, 2) adjusting the heating in common areas, 3) reducing air leakage out of buildings and 4) adjusting the settings of lighting sensors and timers. All are effectively free from investments and also applicable on buildings with similar issues. Thus, these are effective methods of saving energy and consequently, saving money in recently built buildings. The methods are tailored for Ekebyvallen but are with benefit considered for apartment buildings of both recent date and those built before 2000.
8

Energy use in buildings and design requirements : the energy costs and financial costs of building materials, structures and space heating, the detailed patterns of use of heating systems in dwellings, and their interactions : their implications for design

Sansam, Robert Verdon January 1981 (has links)
The primary energy costs of building materials and structures are discussed and comparisons are made between typical dwelling types. The economics of alternative wall, roof and floor constructions, providing various levels of insulationy are examined. Costs are assessed for a number of periods from 1970 to early 1980 for heating by gas and night rate electricity. The effect of price changes-on the economic attractiveness of insulation is investigated and the likely effects of future price rises are considered. It is concluded that, in certain circumstances, higher levels of insulation than those normally used in the UK have been economically attractive for the last few years and may possibly become more so. A survey of over fifty local authority houses with central heating, carried out by the author in Spring 1978, is described. Three types of houses of similar size were involved, having gas-fired 'wet' systems, and ducted warm air heating from electric storage and gas-fired units respectively. The survey was designed to determine certain aspects of occupant behaviour relevant to fuel consumption. Using regression techniques, relationships are obtained which explain more than two thirds of the variance of mean useful energy input rate between the houses of a given type in cold weather in terms of hours of use of central heating window opening habits, and for warm air heating, the closing of outlet registers. It was also revealed that for the house types with gas-fired heating the number of hours of use of the central heating was strongly influenced by household size and occupancy patterns. The implications for building design of the effects of occupant behaviour and of financial and energy costs are discussed.
9

Aproveitamento de fontes alternativas para redução do consumo de energia elétrica e reflexos nos seus custos / Utilization of alternative sources for reducing power consumption and its consequences in costs

Dutra, Adriane 17 September 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Residential consumption accounts for around one third of total energy consumed in Brazil. The electric shower is the main component of this consumption, along with air conditioning. Hence, much research has been conducted in order to reduce the consumption of this sector and the use of alternative energy sources. Among these include mainly solar and geothermal. This thesis aims to establish the bases for assessing the structure of household consumption in order to develop a methodology to reduce power consumption. A prototype was developed in the CEEMA experimental area (UFSM), with the assembly of two prototypes: a solar collector associated with the two types of heating, electric and gas, the other, a geothermal prototype system for surface environments conditioning and pre-heating water. A retrospective on the main alternative to replace the traditional electric shower and air conditioner was conducted as well as ways to reduce heating losses. Practical data were automatically collected to demonstrate the energy efficiency of the studied environment which can be residential, seeking to reduce power consumption and thermal energy and the reflections in the final cost of electric power. The use of thermal sources seen in this thesis was used to demonstrate viable and tangible results in reducing energy consumption and electric power. These results were extrapolated to the region south of the country indicating the possibility of reducing the use of primary energy and, consequently, the conservation of the environment. / O consumo residencial representa em torno de um terço do total de energia consumida no Brasil. O chuveiro elétrico é o principal componente deste consumo, juntamente com o ar condicionado. Assim, muitas pesquisas têm sido realizadas, visando à diminuição do consumo deste setor e o aproveitamento de fontes de energia alternativas. Dentre as quais se destacam a energia solar e geotérmica. Esta dissertação tem como objetivo estabelecer as bases da avaliação da estrutura de consumo residencial visando à obtenção de uma metodologia para reduzir o consumo de energia elétrica. Foi desenvolvido um protótipo habitável de residência no Campus Experimental do CEEMA (UFSM), com a montagem de dois protótipos: um com coletor solar associado a dois tipos de aquecimento, elétrico e a gás, outro, um protótipo de sistema geotérmico superficial para condicionamento de ambientes e pré-aquecimento de água. Foi feita uma retrospectiva nas principais alternativas para a substituição do chuveiro elétrico tradicional e do condicionador de ar bem como das formas de redução de perdas para aquecimento. Dados práticos foram coletados automaticamente para demonstrar a eficientização energética do ambiente estudado que pode ser residencial , buscando a redução do consumo de potência e energia térmica e os reflexos nos custos finais com energia elétrica. O aproveitamento das fontes térmicas vistas nessa dissertação foi utilizado para demonstrar as alternativas viáveis e resultados concretos na redução do consumo e potência elétrica. Estes resultados foram extrapolados para a região Sul do país indicando a possibilidade de diminuição da utilização primária de energia e, por conseqüência, a conservação do meio ambiente.
10

Análise dos dispêndios energéticos e econômicos da implantação de eucalipto /

Gatin, Edse Amanda Bertalha, 1974- January 2010 (has links)
Resumo: O presente trabalho teve por objetivo analisar e comparar os dispêndios energéticos e econômicos da implantação de eucalipto, região de Botucatu, no município de Itatinga, estado de São Paulo. Comparando-se os gastos energéticos com o econômico, pode haver divergência, segundo seu tipo, fonte e forma, pois a análise energética capta as relações estruturais da produção, e a econômica, situações conjunturais de mercado. Utilizaram-se dados de fontes primárias e secundárias. A construção do itinerário técnico e informações da implantação de eucalipto foram obtidos em pesquisas realizadas em campo, diretamente com os técnicos e responsáveis pela operação. De fontes secundárias foram coletados dados referentes aos salários dos diaristas e tratoristas e os valores de maquinários e implementos agrícolas. A implantação de eucalipto é um conjunto de operações com investimentos em máquinas, consumo de combustível e de lubrificante, insumos e mão-deobra, representando dispêndios energéticos e econômicos. Nesta análise a entrada energética foi classificada e quantificada conforme o seu tipo, energias diretas e energias indiretas, sendo a direta dividida em energia biológica e fóssil e a indireta em energia industrial. A análise econômica foi realizada separando as energias segundo seu tipo, fonte e forma, igualmente a análise energética. Pela análise energética o sistema quantificou um dispêndio de 21.831,76 MJ . ha-1, sendo que os fertilizantes químicos foram os que tiveram maior participação (56,05%). Pela análise econômica os dispêndios da implantação de eucalipto foram de R$ 3.884,18 . ha-1, os fertilizantes participaram deste dispêndio com cerca de 36,48%. Comparando a análise energética com a econômica, verificou-se que a energia direta fóssil tem uma participação na vertente energética de 18,97% e na vertente econômica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This report aims to analyze and compare economic and energy costs from eucalyptus implementation, Botucatu region, Itatinga town, São Paulo state in Brazil. Comparing the economic costs with the energy costs, there can be differences about type, source and format because the energy analysis gets production structure relation, and the economic checking is related to market movements. It was used in this, data from second and first kind of sources. The building of the technical itinerary and eucalyptus implementation information were obtained from researches made in the field, directly with technicians and people responsible for the operation. From second sources, it was collected data refer to salary of daily and tractor drivers and the also values from agricultural machinery and machinery in general. The implementation of the eucalyptus is a group of operations with investments in machines, fuels use and lubricants, inputs and labor, which brings economic and energy costs. In this analysis the energy was classified and quantified by its own type, direct and indirect energy; so that the direct energy was divided in fossil and biological and the indirect to industrial energy. The economical analysis was done in the same way as the energy. By the economic analysis the system quantified a cost of 21.831,76 MJ. ha-1, in a way that the chemical fertilizers had the biggest role (56,05%). By the economic analysis the cost of the eucalyptus implementation was R$ 3.884,10 . ha-1, the fertilizes were about 36,48%. Comparing those analysis, it was checked that direct energy from fossil has a great role in energetic aspect of 18,97% and in the economic aspect of 5,24%. In a long term this system may have implications in the energetic sustainable view because it depends on non-renewable sources as well as a high cost when using these energies where its value is determined by the market / Orientador: Osmar de Carvalho Bueno / Coorientador: Maura Seiki Tsutsui Esperancini / Banca: Luiz Cesar Ribas / Banca: Luis Carlos Ferreira de Almeida / Mestre

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