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## ‣ Energy performance of a production system of eucalyptus; Desempenho energético de uma produção de eucalipto

ROMANELLI, Thiago L.; MILAN, Marcos
Fonte: Departamento de Engenharia Agrícola - UFCG Publicador: Departamento de Engenharia Agrícola - UFCG
Tipo: Artigo de Revista Científica
Português
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Maximizing yields is opposed to the goal of minimizing the use of inputs. In the context of system rationalization, the addition of non-economic parameters in the decision making and the magnitude of eucalyptus plantation in Sao Paulo State, Brazil led to this study. The objective was to establish the flows and to evaluate the performance of energy transformations on eucalyptus production. The evaluated system presented three alternatives of soil acidity management: lime, ash and sludge application. The applied indicators were energy return on investment, energy intensity and energy balance, which meant, respectively, the return over energy investment, the energy content of biomass and the energy obtained per area. For the basic scenario, lime, EROI was 58.5 MJ MJ-1, energy intensity was 124.7 MJ m-3, and the energy balance was 2120.7 GJ ha-1. The required energy was larger when ash (5.2%) and sludge (57.2%) were used. The main inputs were, in order, fuel, fertilizers, herbicide and lime. Harvesting was the main operation (56.7%), followed by subsoiling. Fuel in harvesting, fertilizers and lime summed 79.6% of the total energy. The sensitivity of the system showed that the material used to control soil acidity had more effect on the energy demand (up to +57.4%) than the suggested scenarios (-5.3% when the field efficiency was increased).; O contexto da racionalização dos sistemas de produção...

## ‣ Does Reform of Energy Sector Networks Improve Access for the Poor?

Powell, Stephen; Starks, Mary
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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Unless energy can be produced and delivered more cheaply, it will stay beyond the reach of many of the poor. For energy delivered through networks, the costs that matter are not only the unit energy costs, but the costs of extending the network--into an urban slum, for example, or to a rural town. Extending a network can be very expensive--a major barrier to access for poor households and small or isolated communitieds. A central goal of the reform of electricity and gas networks, now occurring in an increasing number of developed and developing countries, is to provide incentives to reduce the costs of producing energy and getting it to consumers. New technologies in electricity are drastically reducing costs. But transmission costs are still a major hurdle to expanding networks in isolated or lightly populated areas. As a result it is the urban poor who stand the greatest chance of benefiting from network reform. For the rural poor, alternative solutions, including mini-grid and off-grid services, may be required.

## ‣ Unlocking Commercial Financing for Clean Energy in East Asia

Wang, Xiaodong; Stern, Richard; Limaye, Dilip; Mostert, Wolfgang; Zhang, Yabei
Fonte: Washington, DC: World Bank Publicador: Washington, DC: World Bank
Português
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Overwhelming evidence indicates that climate change, caused in large part by human activities, is already adversely impacting all people, with the very real prospect of worse to come. Nevertheless, a global treaty to curb carbon emissions remains elusive. In East Asia, all middle-income countries have set national targets for energy efficiency and renewable energy, and some even have targets for carbon reduction. This report focuses on recent experiences in applying public financing instruments and tries to draw the lessons to date: when and how to use the instruments, which instrument to select, and how to design and implement them. The wide range of financial instruments designed to support and catalyze clean energy investment over the last decade is truly remarkable. Such instruments include credit lines and risk guarantees designed to increase both the capacity and confidence of commercial banks for clean energy lending; dedicated funds and concessional financing mechanisms to kick-start new technologies; mezzanine and equity financing targeted at start-ups; small and medium enterprises and energy service companies; and various consumer financing instruments designed to lower the upfront costs of clean energy equipment. This report systematically reviews the successes and failures of innovative interventions and distills the lessons of applying them. This report is organized in following four parts: part one gives overview; part two focuses on financing energy efficiency; part three focuses on financing renewable energy; and part four focuses on clean energy financing case studies.

## ‣ Nicaragua : Energy Sector Policy Note, Executive Summary

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Português
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The increase in oil prices has created a growing economic pressure in Nicaragua. The electric power industry, especially, has generated controversy, because electricity prices have not kept pace with the costs of production. The situation at the beginning of 2006 was clearly unsustainable, and the entry of a new government provided an opportunity to refresh the vision of the sector, and address the problems. The objective of this note is to provide a balanced approach, taking into account both the short-term and long-term prospects of the sector, together with the lessons learned in similar situations. The questions facing the sector relate to its financial situation, the legal framework, the patterns of use of energy in Nicaragua, access and coverage of electric power, and its fiscal impact. Possibly the most important recommendation is to attenuate the disagreements with the government and seek areas of cooperation to improve the conditions of service. This should involve a quantification of the financial losses...

## ‣ Scaling Up Renewable Geothermal Energy in Indonesia

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Português
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## ‣ The Department of Energy’s Home Energy Score: Can a home energy report influence consumers’ willingness to pay for more energy efficient homes?

Bremer, Kristen
Tipo: Masters' project
Publicado em 24/04/2013 Português
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The residential sector accounts for a substantial percentage of total energy use in the United States. Newer homes built under the ENERGY STAR label have increased awareness for home energy efficiency, but there is no standard metric for evaluating the energy use of older housing stock. To fill this gap the U.S. Department of Energy (DOE) created the Home Energy Score (HEScore) that scores existing homes on a 10-point scale based on energy performance. The score, along with a detailed home report, provides homeowners with a list of recommended improvements that – if implemented – will increase a home’s efficiency and HEScore. Through this program the DOE hopes to improve the overall efficiency of U.S. homes. This master’s project investigates behavioral and economic factors that influence homeowners’ willingness to pay (WTP) for energy-efficient home improvements, specifically as they relate to the DOE’s HEScore. An experiment using a contingent valuation study was designed to measure how situational factors and the decision environment influence a homeowner’s WTP for specific energy-efficient improvements. The experiment was delivered via an online survey to more than 1,600 current homeowners, home buyers and home sellers throughout the U.S. A response rate of 56 percent was achieved. Results of the study indicate that no single agent influences a homeowner’s choice in their WTP for energy-efficient improvements; rather it is a complex mix of socioeconomic...

## ‣ The Integration of nearthreshold and subthreshold CMOS logic for energy minimization

Hicks, John
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
Português
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With the rapid growth in the use of portable electronic devices, more emphasis has recently been placed on low-energy circuit design. Digital subthreshold complementary metal-oxide-semiconductor (CMOS) circuit design is one area of study that offers significant energy reduction by operating at a supply voltage substantially lower than the threshold voltage of the transistor. However, these energy savings come at a critical cost to performance, restricting its use to severely energy-constrained applications such as microsensor nodes. In an effort to mitigate this performance degradation in low-energy designs, nearthreshold circuit design has been proposed and implemented in digital circuits such as Intel's energy-efficient hardware accelerator. The application spectrum of nearthreshold and subthreshold design could be broadened by integrating these cells into high-performance designs. This research focuses on the integration of characterized nearthreshold and subthreshold standard cells into high-performance functional modules. Within these functional modules, energy minimization is achieved while satisfying performance constraints by replacing non-critical path logic with nearthreshold and subthreshold logic cells. Specifically...

## ‣ Energy use pattern in vegetable production under fadama in north central Nigeria

Ibrahim,H. Y.
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 Português
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The aim of this research was to examine the energy use pattern, energy use efficiency and energy productivity for vegetable production under Fadama or the seasonally flooded or floodable plains along major savanna rivers in north central Nigeria. To achieve these objectives, the data for the production of four major vegetables produced under Fadama (Onion, Tomato, Sweet and Hot Pepper) were collected from 192 Fadama farmers. The results show that Tomato production was the most energy intensive among the four vegetables investigated. For all the vegetables, the usage of non-renewable energy inputs such as petrol and urea fertilizer was quite substantial as such, the efficiency of energy use and energy productivity were very low. The energy use efficiency were, 0.20, 0.10, 0.10 and 0.06, while the energy productivity were 0.25, 0.12, 0.13 and 0.07 for Onion, Tomato, Sweet and Hot Pepper respectively. However, to enhance the energy use efficiency and energy productivity of the system, the usage of renewable energy inputs especially organic manure should be promoted. In addition, energy efficient water pumps should be introduced into the Fadama communities.

## ‣ Efficient use of energy in the ventilation and cooling of mines

Du Plessis,J. J. L.; Marx,W. M.; Nell,C.
Fonte: Journal of the Southern African Institute of Mining and Metallurgy Publicador: Journal of the Southern African Institute of Mining and Metallurgy
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 Português
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Escalating energy and electricity costs have become one of the largest drivers of expenditure in mining operations. Over the last eight years, energy costs have tripled when expressed as a percentage of total expenses in South African mines. In an effort to manage and reduce electricity costs, energy management strategies can be developed, inefficient operating units replaced, and the operation of energy-consuming components of ventilation systems optimized. Power consumption on mines is controlled mainly by three strategies, namely load clipping, by which energy use is reduced for certain parts of the day; load shifting, by which energy use is shifted to other parts of the day; and energy efficiency, by which energy use is reduced permanently. In this paper several projects that were implemented using the first two strategies of load clipping and load shifting are investigated. The actual and potential savings that can be achieved by implementing such energy-saving interventions are presented. To reduce the operating costs of ventilating and cooling underground mines permanently, system optimization studies must be completed. Methods that can be used to reduce energy usage by optimizing cooling and ventilation systems are described...

## ‣ Effects of L-carnitine in layer diets containing different fat sources and energy levels on hen performance and egg quality

Corduk,M.; Sarica,S.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2008 Português
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The study was conducted to determine the effects of feeding diets containing two levels of metabolisable energy (normal or low) and three sources of fat (palm-, sunflower- or fish-oil) with or without L-carnitine (0 or 500 mg/kg diet) on the performance and egg quality parameters of Brown egg-type laying hens. The hens receiving the low energy diet had significantly higher body weights and feed intakes (FI) than the birds on the normal energy diet, but their feed conversion ratio (FCR) was poorer. L-carnitine in the diet containing sunflower oil (SO) increased FI significantly, resulting in a poorer FCR. However, the FI and FCR were higher when the fish oil (FO) was added to diets without L-carnitine compared to the other diets. The palm oil (PO) supplemented diet without L-carnitine significantly decreased the specific gravity of the eggs. L-carnitine inclusion into the diet containing PO significantly increased the Haugh unit and albumen index of the eggs, while the inclusion of FO in the low energy diet increased the Haugh unit and albumen index significantly. However, when PO was included these parameters decreased significantly. The addition of L-carnitine to the normal energy diet reduced the pH of the egg yolk, while it increased egg yolk pH when added to the low energy diet. The inclusion of FO in the low energy diet resulted in a significant increase in yolk pH. Albumen pH was significantly decreased by dietary L-carnitine supplementation...

## ‣ New markets for renewable industries: Developing countries - Turkey, its potential and policies

Kaya,Durmus; Kilic,Fatma Canka
Fonte: Journal of Energy in Southern Africa Publicador: Journal of Energy in Southern Africa
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2015 Português
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For today's world, energy is a huge requirement for economic, industrial and social life. The necessity of energy is increasing quite rapidly to keep pace with the technological and economical advancements and this brings about many energy problems like, dependence on energy importation, environmental pollution, global warming, increasing cost of energy expenses and inefficiency in energy use etc. Countries are working very hard to solve these problems. To supply the energy needs and protect our planet's future safety, it is very important to generate clean energies. In this context, governments give huge amounts of incentives for renewable energy generations and support related investments in many countries. In this study, the importance of renewable energy usage, recent incentives, renewable energy policies in Turkey and some developed countries are investigated and compared. It is also aimed to examine the real situation of renewables in Turkey by giving the latest numbers and make a contribution of future developments for these clean energies in Turkey. In this regard, some barriers and recommendations are also submitted.