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‣ Critical factors to be considered when planning the implementation of environmental improvements and energy saving

Santos, Juliane Barbosa dos; Chiappetta Jabbour, Charbel Jose
Fonte: Univ Cape Town, Energy Res Centre Publicador: Univ Cape Town, Energy Res Centre
Tipo: Artigo de Revista Científica Formato: 22-29
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To identify the critical success factors in the adoption of energy efficiency actions in Brazilian hospitals and describe their behaviour are the objectives of this paper. In order to achieve these goals, a literature review was performed on green management and energy efficiency. This was the basis to define the questions of the interview script applied to two hospitals located in the state of Sao Paulo, Brazil. The interview script application was complemented by secondary data and direct observation. The results showed that: a) the studied hospitals are embracing environmental management actions more often and, whenever possible, energy efficiency actions are taken as well; and b) in the cases analysed top management support, commitment with the environment, green process design and employee empowerment were some of the most relevant critical success factors to the accomplishment of energy efficiency actions. These findings may be of interest to emerging countries, including BRICS (Brazil, Russia, India, China and South Africa).

‣ Interfuel substitution in the consumption of energy in the United States

Baughman, Martin Lynn; Joskow, Paul L.; Zerhoot, Frederick S.
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Relatório Formato: 4535561 bytes; application/pdf
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The effects of alternative public policies on the consumption and prices of various forms of energy in the United States depends critically on the nature of consumer demands for fuels and the supply characteristics of these fuels. Previous work on energy demand has tended to concentrate on the demand for a particular fuel as determined by standard economic variables such as the price of the fuel, income levels, sometimes the price of alternative fuels, and other demographic characteristics of the consuming population. In this work the consumer decision making process is viewed as being composed of two steps. First, the consumer decides that he wants a particular service and, secondly, seeks to find the fuel that will provide this service most cheaply. This view leads us to concentrate on substitution possibilities among fuels for particular services rather than own-price elasticities for a particular fuel. This paper presents results for the determinants of energy consumption in the residential and commercial sector in the United States. First, a discussion of the conceptual model used for fuel choice decisions is presented. Then, empirical results are given for appliance choices in the residential sector for four selected appliances and for the "fuel-split" of aggregate energy consumption among the three fuels used in the residential and commercial sector. The own-price and cross-price elasticities are estimated and discussed. Next...

‣ Solar energy dehumidification experiment on the Citicorp Center building : final report

Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 9053484 bytes; application/pdf
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The technical and economic feasibility of using solar energy to reduce conventional energy consumption of a large urban commercial building were studied in depth. Specifically, solar assisted dehumidification of ventillation air to reduce conventional air conditioning requirements for the Citicorp Center in New York City was investigated. A detailed computer simulation of yearly operation was made on an hourly basis using New York City temperature, humidity and solar data. Several system configurations were examined and were defined each operating in its most efficient fashion. It was found that maximum energy savings was achieved by optimizing the operation of the conventional system. Maximum energy savings could be achieved by the following, in order of decreasing impact: optimization of the operation of the conventional system, use of additional conventional equipment for energy savings, and use of the solar assisted system.; NSF/RA-760003 Prepared for National Science Foundation, RANN/Research Applied to National Needs under Grant no. PTP-75-05156

‣ Independent assessment of energy policy models : two case studies

Massachusetts Institute of Technology. Model Assessment Group.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 13822037 bytes; application/pdf
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Energy policy models are playing an increasingly important and visible role in supporting both private and public energy policy research and decision making. As importance has increased so too has the need for model review and assessment to assist in establishing model credibility for users and those affected by model-based policy research. Toward this end EPRI has sponsored the M.I.T. Energy Laboratory in a one-year project to assess two important energy system models, the Baughman-Joskow Regionalized Electricity Model and the Wharton Annual Energy Model, and to identify and analyze organizational and procedural issues in the model assessment process.; Prepared for the Electric Power Research Institute, Palo Alto, CA.

‣ Independent assessment of energy policy models : two case studies

Massachusetts Institute of Technology. Model Assessment Group.
Fonte: MIT Energy Laboratory Publicador: MIT Energy Laboratory
Tipo: Relatório Formato: 13822037 bytes; application/pdf
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Energy policy models are playing an increasingly important and visible role in supporting both private and public energy policy research and decision making. As importance has increased so too has the need for model review and assessment to assist in establishing model credibility for users and those affected by model-based policy research. Toward this end EPRI has sponsored the M.I.T. Energy Laboratory in a one-year project to assess two important energy system models, the Baughman-Joskow Regionalized Electricity Model and the Wharton Annual Energy Model, and to identify and analyze organizational and procedural issues in the model assessment process.; Prepared for the Electric Power Research Institute, Palo Alto, CA.

‣ Solar project cost report for Irvine Elementary School, Irvine, California; Irvine Elementary School, Irvine, California

Mueller Associates (Baltimore, Md.); United States -- Dept. of Energy. -- Office for Conservation and Solar Applications; United States -- Dept. of Energy. -- Office of the Assistant Secretary for Conservation and Solar Applications; PRC Energy Analysis C
Fonte: Dept. of Energy, Office of Assistant Secretary for Conservation and Solar Applications; National Technical Information Service; Dept. of Energy, Office of Assistant Secretary for Conservation and Solar Applications ( Washington ); National Technical Information Service Publicador: Dept. of Energy, Office of Assistant Secretary for Conservation and Solar Applications; National Technical Information Service; Dept. of Energy, Office of Assistant Secretary for Conservation and Solar Applications ( Washington ); National Technical Information Service
Tipo: Artigo de Revista Científica Formato: 28 p. in various pagings : ; 28 cm.
Publicado em //1979 Português
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Apr. 11, 1979.; National solar data program.; National solar heating and cooling demonstration program.; MONTHLY CATALOG NUMBER: gp 80007819; (Statement of Responsibility) prepared for Department of Energy, Office of Assistant Secretary for Conservation and Solar Applications, National solar heating and cooling demonstration program, under contract number EG-77-C-01-2522 ; prepared by Mueller Associates, Inc., under subcontract to PRC Energy Analysis Company.

‣ Solar project description for Reedy Creek Utilities, Co., Inc. office building; Reedy Creek Utilities Co., Inc. office building

PRC Energy Analysis Company; United States -- Department of Energy. -- Office of Conservation and Solar Applications; International Business Machines Corporation -- Federal Systems Division; Mueller Associates; Ehrenkrantz Group
Fonte: Dept. of Energy, Office of Conservation and Solar Applications; [For sale by the National Technical Information Service]; Dept. of Energy, Office of Conservation and Solar Applications ( [Washington] ); [For sale by the National Technical Information Service] ( [Springfield, Va.] ) Publicador: Dept. of Energy, Office of Conservation and Solar Applications; [For sale by the National Technical Information Service]; Dept. of Energy, Office of Conservation and Solar Applications ( [Washington] ); [For sale by the National Technical Information Service] ( [Springfield, Va.] )
Tipo: Artigo de Revista Científica Formato: iv, 44 pages : illustrations ; 28 cm.
Publicado em //[1980] Português
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National solar heating and cooling demonstration program.; National solar data program.; July 11, 1978.; (Statement of Responsibility) prepared for the Department of Energy, Office of Assistant Secretary for Conservation and Solar Applications, under contract number EG-77-C-01-2522, by PRC Energy Analysis Company, in cooperation with IBM Corporation, Federal Systems Division, Mueller Associates, Incorporated, the Ehrenkrantz Group.

‣ Solar project description for Hogate's Restaurant; Hogate's Restaurant

PRC Energy Analysis Company; United States -- Dept. of Energy. -- Office of Conservation and Solar Applications; International Business Machines Corporation -- Federal Systems Division; Ehrenkrantz Group; Mueller Associates; Mueller Associates (Baltimore,
Fonte: Dept. of Energy; National Technical Information Service; Dept. of Energy ( Washington ); National Technical Information Service Publicador: Dept. of Energy; National Technical Information Service; Dept. of Energy ( Washington ); National Technical Information Service
Tipo: Artigo de Revista Científica Formato: iv, 35 p. : ill. ; 28 cm.
Publicado em //1979 Português
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May 9, 1978.; National solar data program.; National solar heating and cooling demonstration program.; MONTHLY CATALOG NUMBER: gp 80010092; (Statement of Responsibility) prepared for the Department of Energy, Office of Assistant Secretary for Conservation and Solar Applications, under contract number EG-77-C-01-2522, by PRC Energy Analysis Company, in cooperation with IBM Corporation, Federal Systems Division, Mueller Associates, Incoporated, The Ehrenkrantz Group.

‣ Quantitative analysis of the stability of Japan's energy system

Oyama, Tatsuo
Fonte: MIT Energy Lab Publicador: MIT Energy Lab
Tipo: Trabalho em Andamento Formato: 2192890 bytes; application/pdf
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In order to measure Japan's energy system's stability under an uncertain future availability of energy resources, we built a mathematical programming / economic equilibrium model based upon linear programming techniques. Future uncertainty is expressed as random variables with a given probability distribution, and the economic equilibrium point is obtained by iterative convergent computation. Numerical experiments show an optimal energy supply-demand structure with equilibrium prices of primary energy resources at the future target year, then we obtain supply stability and instability probabilities of our energy system. From shadow price analysis of an optimal solution our energy policy is quantitatively evaluated.

‣ A techno-economic study of energy efficiency technologies for supermarkets in South Africa

Pather-Elias,Simisha; Davis,Stephen; Cohen,Brett
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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The food retail sector is energy intensive, consuming large amounts of electricity for refrigeration, air-conditioning and cooking. Retailers are aiming to reduce their electricity consumption in supermarkets and thus their carbon footprint using energy efficiency technologies. This paper reports on a techno-economic analysis of energy efficient technologies to recommend to the food retail sector for use in supermarkets. The targets and needs of food retail companies were surveyed and thereafter, the retailers were divided into three categories. Category 1 retailer had the highest targets for electricity and carbon reduction and was willing to take on more risk. Category 2 retailer had intermediate targets and would only use developed technologies, while category 3 retailer would only invest in developed technologies if they were proven to show significant long term saving with short pay back periods. The analysis showed that closed refrigerators had the highest electricity/carbon savings and the highest profit (NPV), followed by heat reclamation from refrigeration. Both these technologies were recommended for category 1 retailers. A combination of heat reclamation, energy efficient lights, fridge curtains, electronic controls for refrigerators and POS power management systems were recommended for category 3 retailers. A combination of the two recommendations was identified for category 2 retailers. Behavioural changes of all staff were identified as important for energy efficiency technologies to work at optimum levels.

‣ Experimental analysis of a solar absorption system with interior energy storage

Pastakkaya,Bilsay; Yamankaradeniz,Nurettin; Kaynakli,Omer; Coskun,Salih; Yamanakaradeniz,Recep
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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This study examines experimentally the cooling application of a solar absorption system with interior energy storage that uses two different auxiliary systems. The experiments were performed at Uludag University, Bursa, Turkey on the 3rd and 4th of August 2010 that had the approximately same average outdoor temperature, 31°C. A solar hot water was delivered via a 40 m2 array of flat plate solar collectors that drove a lithium chloride (LiCl) absorption heat pump with a cooling power peak of 20 kW. A solar-powered air conditioning system was designed for heating and cooling in a test room that had a total floor space of 30 m2. Chilled water produced in the evaporator was supplied to the fan coil units, and the heat of condensation and absorption was rejected by means of a wet cooling tower. An electric heater and an air source heat pump were used as auxiliary systems for the absorption cooling application for two different cases when the solar energy was insufficient. Temperature variations were recorded for the absorption machine components, the test room, and the outdoors. The cooling energy, thermal energy, and daily average coefficient of performance (COP) of the absorption system were calculated for two days. Solar absorption cooling was considered for two different auxiliary systems and is presented in this manuscript. The results showed that the daily average COP of the absorption system was 0.283 for Case 1 and 0.282 for Case 2. For both cases...

‣ The impacts of energy prices and technological innovation on the fossil fuel-related electricity-growth nexus: An assessment of four net energy exporting countries

Fei,Qin; Rasiah,Rajah; Leow,JiaShen
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2014 Português
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This study uses annual data from 1974 to 2011 to examine the long-run and short-run relationships between fossil fuel powered electricity consumption, economic growth, energy prices and technological innovation for four net energy exporting countries. Canada, Ecuador, Norway and South Africa are chosen as the main research background in order to investigate how the development degree and economic dependence on energy exports affect the electricity-growth nexus. Based on the results drawing from the ARDL approach and the Granger causality test, economic growth positively influences the variation in fossil fuel powered electricity consumption in both the short-run and long-run for all four countries. The reverse causality from electricity consumption to economic growth is only evident in Ecuador and Norway. The degree of dependence on energy exports is a contributory factor of explaining the causality puzzle of the electricity-growth nexus. Given the fact that technological innovation does not benefit fossil fuel powered electricity generation, this paper suggests these net energy exporting countries to replace fossil fuel with more sustainable and effective sources in the electricity generation process.

‣ A systems approach to urban water services in the context of integrated energy and water planning: A City of Cape Town case study

Ahjum,Fadiel; Stewart,Theodor J
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2014 Português
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The City of Cape Town derives the bulk of its present water supply from surface water resources and is the central water service authority for metropolitan consumers. The City is also a provider of bulk water to neighbouring municipalities. An exploration of the energy consumption for water and sanitation services for the City of Cape Town was conducted with an emphasis on water supply augmentation options for the near future (2011-2030). A systems analysis of municipal urban water services was undertaken to examine the energy requirements of supply alternatives and the efficacy of the alternatives in respect of supply availability and reliability. This was achieved using scenario based analysis incorporating a simple additive value function, to obtain a basic performance score, to rank alternatives and facilitate a quantitative comparison. Utilising the Water Evaluation and Planning hydrological modelling tool, a model for urban water services was developed for the City and used to conduct scenario analyses for a representative portfolio of previously identified options. Within the scope of the research objectives, the scenario analyses examines the direct energy consumption for the provision of water services for the City as influenced by external factors such as population growth...

‣ Challenges for local community development in private sector-led renewable energy projects in South Africa: An evolving approach

Wlokas,Holle Linnea; Boyd,Anya; Andolfi,Marco
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 Português
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The Renewable Energy Independent Power Producer Procurement Programme in South Africa is intended to support the uptake of renewable energy, help address the current energy supply crisis and mitigate greenhouse gas emissions. Notably, it also requires project developers to engage with socio-economic development at the local level. The distributed nature of renewable energy generation may induce a more geographically dispersed pattern of development, and renewable energy sites can be highly suited to rural locations with otherwise poor potential to attract local inward investment. Socio-economic development and enterprise development are two of seven economic development elements in the programme. In order to prepare a bid submission, project developers have to assess local socio-economic needs around their project site and develop strategies on how to address these. This paper investigates the challenges for local community development. The research is based on case studies and presents findings from the perspective of a research team working alongside project developers. Early findings indicate that there are potential community benefits from commercial wind projects, providing an appropriate community engagement process that is aligned with the project cycle determined by the tender process and engineering requirements. The Passive Community Needs Assessment approach is introduced as a possible solution.

‣ Determinants of energy poverty in South Africa

Ismail,Zaakirah; Khembo,Patrick
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 Português
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This paper provides empirical evidence on the determinants of energy poverty in South African households using the National Income Dynamics Survey (NIDS, 2012), while controlling for individual, household and demographic characteristics. This is formulated within a logistic regression framework, while defining energy poverty using the expenditure approach consistent with the definition by the Department of Energy (DoE) of South Africa. The model reveals that household expenditure patterns, race, education level, household and dwelling size, location of the household and access to electricity are important factors in explaining the state of energy in South African households. This paper also discusses limitations in defining energy poverty using the expenditure approach. Finally, some recommendations are made for regulators and policy makers.

‣ Energy improvement in induction furnace using foaming slag with variation of carbon injection

Kipepe,Theodore Mwata; Pan,Xiaowei
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2015 Português
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Energy efficiency is nowadays one of the biggest concerns worldwide. It has become one of the critical matters to any country and industry particularly in South Africa. Because of the complexities and challenges found in industries and especially in foundry, many strategies have been established to measure and regulate more efficiently the energy. Many studies have been conducted in steelmaking process and electrical arc furnace using foaming slag to reduce energy consumption. As such, in this case study, the experiment will be conducted in a small foundry metal casting laboratory using an Induction Furnace (IF), which will reduce energy usage by using the foaming slag and as well pointing out the importance and the impact of carbon rate change on the foaming creation. After experiments all results show that the melting time can be reduced from 42min to 35 min, which is 20% time saving, the electrical energy consumption also has been reduced from 13.93kWh to 10kWh which is 39.3% saving. On the other hand, the foaming slag optimum height was reached at 1 cm. Therefore, a simple modelling has been designed and calculations have been made on heat transfer at the surface opening of the Induction Furnace and temperature loss has been reduced from 878°C to 870°C...

‣ A system methodology for an energy planning model and renewable energy technologies for agriculture in Nigeria

Njoku,P C
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2008 Português
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This paper analyses the system methodology of an energy planning model and renewable energy technology for agricultural operations in Nigeria. The study applies an energy building scenarios approach and with a computer software FORTRAN regression method. Agricultural productivity and value added depend very much on certain factors such as the area of the land under cultivation, extent of multiple cropping, the choice of crop, use of high yielding varieties, use of organic and inorganic fertilizers, the coverage of surface and ground water irrigation schemes, and the extent of mechanization for land preparation.

‣ The potential impact of small-scale flywheel energy storage technology on Uganda's energy sector

Okou,Richard; Sebitosi,Adoniya Ben; Khan,Azeem; Pillay,Pragasen
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2009 Português
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The energy crisis in Uganda has caused a sharp decline in the growth of the industry sector from 10.8% to 4.5% between 2004/5 and 2005/6. This crisis has escalated the power disruptions, which have had adverse effects on various sectors. While business owners have resorted to importation of fossil fuel generators that have increased the cost of production, others have resorted to battery energy storage systems to cater for short outages, which are limited in life span, depth of discharge, among others. These interventions have, thus, further increased the cost of goods and services. In addition, the rural populations using solar home systems incur high battery maintenance and replacement costs. In this paper an electromechanical flywheel battery is proposed as a better alternative in mitigating energy storage problems. It is found that by replacing the battery storage systems with the electromechanical flywheel battery, a saving of up to 35% on cost of energy can be made in the solar home systems and for the industry sector, the power disruptions could be reduced.

‣ Energy savings opportunities at the University of Nigeria, Nsukka

Unachukwu,Godwin Ogechi
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 Português
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This paper examines the potential for energy savings in Nigerian higher institutions with particular reference to the University of Nigeria, Nsukka. Electricity consumption and cost profiles for a period of 10 years indicate a steady rise attributable to marginal improvement in staff living standards, increasing students' enrolment, infrastructural development, preponderant use of inefficient electrical appliances and increasing business activities within the community. Investigations show that about 51% of the total electricity consumption occurs in staff housing units, 16% in students' hostels and the balance in academic and public buildings on the campus. An internal energy policy, awareness creation and establishment of an energy management unit in the University system are some of the measures that can guarantee good savings. This paper estimates electricity savings potentials of 10-20% in Nigerian higher institutions through well articulated and vigorously pursued energy efficiency programmes in the system.

‣ South African renewable energy investment barriers: An investor perspective

de Jongh,Derick; Ghoorah,Dhirendra; Makina,Anesu
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/2014 Português
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As recently as the year 2010, renewable energy contributed less than 1% of all the energy sources in South Africa. Possible reasons include the lack of private sector investment in Renewable Energy technologies. By way of a structured interview methodology, this paper explores the reasons why private investors are reluctant to invest in renewables. The responses point to political, economic, social and technological barriers limiting private investment in renewable energy. Other barriers that were identified include poverty, low levels of education, limited technological readiness and access to the electricity grid. Some of these barriers are specific to the South African context. The paper concludes that a closer relationship between government and the private sector is required to stimulate innovation in the renewable energy sector.