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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.
261

Energy Audit and Accounting for Riksbyggen Fastighetsservice, Gävle

Liu, Yuanyuan, Shen, Yang January 2009 (has links)
<p>Riksbyggen Fastighetsservice is a company whose businesses cope with building construction and related services. The local office of Riksbyggen Fastighetsservice in Gävle has been studied in this project. The local office locates in Näringen 20:4, which was constructed in 1989.</p><p> </p><p>The aim of this project is to make a diagnosis of the current situation; find out the most applicable way of optimizing the operation of the facility in order to reduce the energy consumption, to study costs and possible savings and provide assistance with future energy management.   </p><p> </p><p>Firstly, a study of Energy Balance was conducted. The transmission losses was 57761 KWh; mechanical ventilation losses 3855 KWh; hot tap water heat losses 9579 KWh; natural transmission and infiltration 6897 KWh. On the other hand, heat gain from internal heat was 12707 KWh; solar radiation 8521 KWh; and supply heat 56806 KWh.</p><p> </p><p>Secondly, the energy costs have been checked out. 29655 KWh of electricity was consumed in 2008. 5948 KWh was used by 20 fuses electricity and 23707 KWh was for 25 fuses. Lighting, electrical equipment and machine composed the electricity consumption. Lighting consumes 13278 KWh; equipment consumes 6452 KWh; and machine consumes 9925 KWh. Lighting electricity was composed by office lighting and workshop lighting with 4798 KWh and 8480 KWh respectively.</p><p> </p><p>Electricity cost is very complicated and flexible in Sweden according to effect and consumption. The total cost of electricity consists of electricity commerce fee and electricity transmission net. Electricity commerce fee includes annual fixed fee, electricity fee, energy certificate and tax. Electricity transmission fee includes annual fixed transmission fee, grid fee and tax. Tax plays vital important role which results in huge total cost. The local office spent 43356 kr on electricity in 2008. 4798 kr was spent on office lighting, and 8480 kr was spent on workshop lighting.</p><p> </p><p>On the other hand district heating fee is composed by annual fixed fee, effect fee, energy fee and tax. The local office spent 37142 kr on 56.806 MWh of district heating in 2008. Thus, the local office purchased 86461 KWh of energies and spent 80498 kr in total in 2008.</p><p> </p><p>Thirdly, to assist its energy traces and management, three tables were designed. One table is for annual energy consumption and cost in each month with all information of sub-terms on costs. One table is for annual electricity consumption for each electrical equipment and cost in accordance. Another table is for district heating consumption and cost. </p><p> </p><p>At last, energy saving possibilities was explored. One way is applying improvements or maintenance of the office construction. The result of Energy Balance shows that transmission losses were 57761 KWh which occupies 74% of the total losses, and it is the biggest bite. As the office was constructed in 1989, if improvements and maintenance can be applied to the insulation of floor, roof and walls, or change the windows, the heat losses can be reduced.</p><p> </p><p>However, the other solution might be much more applicable and financial sound. Just go to Clas Ohlson to buy LED 1 W and 3 W lamps to replace the current bulbs. Spending 3009 kr to buy 51 LED incandescent bulbs of 1W effect, and 3576 kr on 24 LED fluorescent of 3W effect, will save 12057 kr every year. The lighting electricity consumption will be reduced from 13278 KWh / year to 264 KWh / year. Instead of spending 16017 kr on lighting, 98% will be reduced, and only 318 kr will be paid. Moreover, the payback is really nice, only 0.42 year. Action! The sooner the better! 20% of energy cost will be saved!</p>
262

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.
263

Energy Audit and Accounting for Riksbyggen Fastighetsservice, Gävle

Liu, Yuanyuan, Shen, Yang January 2009 (has links)
Riksbyggen Fastighetsservice is a company whose businesses cope with building construction and related services. The local office of Riksbyggen Fastighetsservice in Gävle has been studied in this project. The local office locates in Näringen 20:4, which was constructed in 1989.   The aim of this project is to make a diagnosis of the current situation; find out the most applicable way of optimizing the operation of the facility in order to reduce the energy consumption, to study costs and possible savings and provide assistance with future energy management.      Firstly, a study of Energy Balance was conducted. The transmission losses was 57761 KWh; mechanical ventilation losses 3855 KWh; hot tap water heat losses 9579 KWh; natural transmission and infiltration 6897 KWh. On the other hand, heat gain from internal heat was 12707 KWh; solar radiation 8521 KWh; and supply heat 56806 KWh.   Secondly, the energy costs have been checked out. 29655 KWh of electricity was consumed in 2008. 5948 KWh was used by 20 fuses electricity and 23707 KWh was for 25 fuses. Lighting, electrical equipment and machine composed the electricity consumption. Lighting consumes 13278 KWh; equipment consumes 6452 KWh; and machine consumes 9925 KWh. Lighting electricity was composed by office lighting and workshop lighting with 4798 KWh and 8480 KWh respectively.   Electricity cost is very complicated and flexible in Sweden according to effect and consumption. The total cost of electricity consists of electricity commerce fee and electricity transmission net. Electricity commerce fee includes annual fixed fee, electricity fee, energy certificate and tax. Electricity transmission fee includes annual fixed transmission fee, grid fee and tax. Tax plays vital important role which results in huge total cost. The local office spent 43356 kr on electricity in 2008. 4798 kr was spent on office lighting, and 8480 kr was spent on workshop lighting.   On the other hand district heating fee is composed by annual fixed fee, effect fee, energy fee and tax. The local office spent 37142 kr on 56.806 MWh of district heating in 2008. Thus, the local office purchased 86461 KWh of energies and spent 80498 kr in total in 2008.   Thirdly, to assist its energy traces and management, three tables were designed. One table is for annual energy consumption and cost in each month with all information of sub-terms on costs. One table is for annual electricity consumption for each electrical equipment and cost in accordance. Another table is for district heating consumption and cost.    At last, energy saving possibilities was explored. One way is applying improvements or maintenance of the office construction. The result of Energy Balance shows that transmission losses were 57761 KWh which occupies 74% of the total losses, and it is the biggest bite. As the office was constructed in 1989, if improvements and maintenance can be applied to the insulation of floor, roof and walls, or change the windows, the heat losses can be reduced.   However, the other solution might be much more applicable and financial sound. Just go to Clas Ohlson to buy LED 1 W and 3 W lamps to replace the current bulbs. Spending 3009 kr to buy 51 LED incandescent bulbs of 1W effect, and 3576 kr on 24 LED fluorescent of 3W effect, will save 12057 kr every year. The lighting electricity consumption will be reduced from 13278 KWh / year to 264 KWh / year. Instead of spending 16017 kr on lighting, 98% will be reduced, and only 318 kr will be paid. Moreover, the payback is really nice, only 0.42 year. Action! The sooner the better! 20% of energy cost will be saved!
264

Federal and state renewable energy policy : lessons from the late 1970's and early 1980's /

Friedman, Howard Lawrence. January 1993 (has links)
Thesis (M.U.A.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 109-126). Also available via the Internet.
265

Renewable energy generation in developing countries : influence factors and enablers

Banda, Sylvia January 2021 (has links)
Thesis (M. Com. (Accounting)) -- University of Limpopo, 2021 / Since 2008, South Africa has been experiencing significant bottlenecks in its energy supply. The transition to renewable energy is no longer just an option but a necessity. In demonstrating the commitment to the Kyoto Protocol, which requires a reduction in greenhouse gases and is a response to the electricity crisis, various mechanisms have been applied to stimulate renewable energy production. This study examines the effect of the influencing factors and enablers on renewable energy generation in selected developing countries. To this end, the study investigated if the amount invested in renewable energy, economic, governance, environmental and social factors have an impact on renewable energy output produced in the selected emerging economies. Secondary data which comprised of the renewable energy output, investment and proxy data for the other factors being tested was used in the investigation. A quantitative research design was used, and panel data for the periods 2000-2016 was analysed. Results of the study revealed that the renewable energy generation is impacted diversely by the elements tested. A positive causal link was found between the dollar amount invested and the production of renewable energy. Additionally, the study found that governance, economic, environmental, and social factors can influence renewable energy output favourably or unfavourably. Results of the study suggest that policymakers should consider the effect of these variables when formulating policies to accelerate the transition to a sustainable energy supply system. Furthermore, the results provide possible solutions for budgetary constraints which have limited the transformation of the energy industries in the selected developing countries. Potential to investigate this study further on a country by country basis as data becomes available exists. Additionally, mixed methods may be applied to explore a qualitative element in the study. Keywords: Renewable Energy, Non-renewable energy, Green energy
266

The Non-Energy Benefits of Industrial Energy Efficiency : Investments and Measures

Nehler, Therese January 2016 (has links)
Improved industrial energy efficiency is viewed as an important means in the reduction of CO2 emissions and climate change mitigation. Various energy efficiency measures for improving energy efficiency exists, but even evaluated as cost-effective, there seems to be a difference between the energy efficiency measures that theoretically could be undertaken and which measures that actually are realised. On the other hand, industrial energy efficiency measures might yield extra effects, denoted as non-energy benefits, beyond the actual energy savings or energy cost savings. Based on interviews and a questionnaire, results showed that the Swedish industrial firms studied had observed various non-energy benefits. However, few of the non-energy benefits observed were translated into monetary values and included in investment calculations. Results indicated that this non-inclusion could be explained by lack on information on how to measure and monetise the benefits, but even if not translated into monetary values, some of the non-energy benefits were sometimes used qualitatively in investment decisions. The utilisation of the benefits seemed to depend on the type and the level of quantifiability among the perceived benefits. This thesis has also explored energy efficiency measures and non-energy benefits for a specific industrial energy-using process – compressed air. A literature review on energy efficiency in relation to compressed air systems revealed a large variation in which measures that could be undertaken to improve energy efficiency. However, few publications applied a comprehensive perspective including the entire compressed air system. Few non-energy benefits of specific energy efficiency measures for compressed air systems were identified, but the study provided insights into how non-energy benefits should be studied. This thesis suggests that energy efficiency and non-energy benefits in compressed air systems should be studied on specific measure level to enable the observation of their effects. However, the studies also addressed the importance of having a systems perspective; the whole system should be regarded to understand the effects of energy efficiency measures and related non-energy benefits.
267

Energy Analysis of the Closed Greenhouse Concept : Towards a Sustainable Energy Pathway

Vadiee, Amir January 2011 (has links)
The closed greenhouse is an innovative concept in sustainable energy management. The closed greenhouse can be considered as a large commercial solar building. In principle, it is designed to maximize the utilization of solar energy through seasonal storage. In a fully closed greenhouse, there are not any ventilation windows. Therefore, the excess sensible and latent heat must be removed, and can be stored using seasonal and/or daily thermal storage technology. The available stored excess heat can be utilized later in order to satisfy the heating demand in the greenhouse, and also in neighbouring buildings. A model for energy analysis of a greenhouse has been developed using the commercial software TRNSYS. With this model, the performance of various design scenarios has been examined. The closed greenhouse is compared with a conventional greenhouse using a case study to guide the energy analysis. In the semi-closed greenhouse, a large part of the available excess heat will be stored through thermal energy storage system (TES). However, a ventilation system can still be integrated in order to use fresh air as a rapid response indoor climate control system. The partly closed greenhouse consists of a fully closed section and a conventional section. The fully closed section will supply the heating and cooling demand of the conventional section as well as its own demand. The results show that there is a large difference in heating demand between the ideal closed and conventional greenhouse configurations. Also, it can be concluded that the greenhouse glazing type (single or double glass) and, in the case of the semi-closed and partly closed greenhouse, the controlled ventilation ratio are important for the thermal energy performance of the system.  A thermo-economic analysis has been done in order to investigate the cost feasibility of various closed greenhouse configurations. From this analysis, it was found that the load chosen for the design of the seasonal storage has the main impact on the payback period. In the case of the base load being chosen as the design load, the payback period for the ideal closed greenhouse might be reduced by 50% as compared to using peak load. Thus, future studies should explore innovative combinations of short term and seasonal storage. Finally, several energy management scenarios have been discussed in order to find alternatives for improving the energy performance of the closed greenhouses. However, no specific optimal solution has so far been defined. / <p>QC 20111115</p>
268

A HYBRID RECONFIGURABLE SOLAR AND WIND ENERGY SYSTEM

Gadkari, Sagar A. 04 November 2008 (has links)
No description available.
269

China’s Wind Energy Development and Prediction

Wallin, Micah R. 03 September 2010 (has links)
No description available.
270

Marine Current Energy Conversion

Lundin, Staffan January 2016 (has links)
Marine currents, i.e. water currents in oceans and rivers, constitute a large renewable energy resource. This thesis presents research done on the subject of marine current energy conversion in a broad sense. A review of the tidal energy resource in Norway is presented, with the conclusion that tidal currents ought to be an interesting option for Norway in terms of renewable energy. The design of marine current energy conversion devices is studied. It is argued that turbine and generator cannot be seen as separate entities but must be designed and optimised as a unit for a given conversion site. The influence of support structure for the turbine blades on the efficiency of the turbine is studied, leading to the conclusion that it may be better to optimise a turbine for a lower flow speed than the maximum speed at the site. The construction and development of a marine current energy experimental station in the River Dalälven at Söderfors is reported. Measurements of the turbine's power coefficient indicate that it is possible to build efficient turbines for low flow speeds. Experiments at the site are used for investigations into different load control methods and for validation of a numerical model of the energy conversion system and the model's ability to predict system behaviour in response to step changes in operational tip speed ratio. A method for wake measurements is evaluated and found to be useful within certain limits. Simple models for turbine runaway behaviour are derived, of which one is shown by comparison with experimental results to predict the behaviour well.

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