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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.
51

ENERGY AUDIT OF A BUILDING : Skogmursskolan in Gävle

Zheng, Yilong, Wang, Shuang January 2009 (has links)
The building was selected for a detailed study of heating consumption that is located in the city of Gävle and the top fifth energy consumption in this city in 2006. Classrooms, workshops, offices and a restaurant with kitchen compose the building of two floors.The aim of this thesis is to design the best approach to reduce consumption and achieve a high efficiency of energy utilization in these companies. The project is going to optimize the system.Series of measurements are taken to achieve the heat losses. The heat losses are calculated through the building in the first step. Afterwards, with the result of ventilation, heating and electrical usage an energy balance is made to calculate the efficiency of the installation through the building envelop.It is to study the indoor climate within a building, as well as energy consumption for the entire building. In addition, it is also used to measure the temperature of ventilation systems and check the schedule of air supply.Analyze the result of the value that is measured. Improve some part of this building that reduces the heating consumption.At last give some suggestion like construction a new roof reduce the heat loss and change some door that is not correct in the building.
52

none

Sheu, Song-maw 10 July 2007 (has links)
none
53

Predictions of monthly energy consumption and annual patterns of energy usage for convenience stores by using multiple and nonlinear regression models

Muendej, Krisanee 15 November 2004 (has links)
Thirty convenience stores in College Station, Texas, have been selected as the samples for an energy consumption prediction. The predicted models assist facility energy managers for making decisions of energy demand/supply plans. The models are applied to historical data for two years: 2001 and 2002. The approaches are (1) to analyze nonlinear regression models for long term forecasting of annual patterns compared with outdoor temperature, and (2) to analyze multiple regression models for the building type regardless of outdoor temperature. In the first approach, twenty four buildings are categorized as base load group and no base group. Average temperature, cooling efficiencies, and cooling knot temperature are estimated by nonlinear regression models: segment and parabola models. The adjusted r-square results in good performance up to ninety percent accuracy. In the second approach, the other selected six buildings are categorized as no trend group. This group does not respond to outdoor temperature. As the result, multiple a regression model is formed by combination of variables from the nonlinear models and physical building variables of cooling efficiency, cooling temperature, light bulbs, area, outdoor temperature, and orientation of fronts. This model explains up to sixty percent of all convenience stores' data. In conclusion, the accuracy of prediction models is measured by the adjusted r-square results. Among these three models, the multiple regression model shows the highest adjusted r-square (0.597) over the parabola (0.5419) and segment models (0.4806). When the three models come to the application, the multiple regression model is best fit for no trend data type. However, when it is used to predict the energy consumption with the buildings that relate to outdoor temperature, segment and parabola model provide a better prediction result.
54

Sustainability assessment of future energy strategies for Milton Keynes.

Titheridge, Helena. January 2004 (has links)
Thesis (Ph. D.)--Open University. BLDSC no. DXN088257.
55

Effects of incorporating renewable energy sources into the electricity grid

Sakib, Nazmus 08 June 2015 (has links)
With the increasing demand for energy throughout the world, the environment around us is getting severely affected. The conventional energy sources (coal, oil and gas) are unfortunately the biggest polluters of the environment. The aforementioned energy sources emit greenhouse gases like carbon dioxide and methane, which are responsible for global warming and ozone layer depletion. The only feasible answer to this problem is to reduce the use of the conventional energy sources and focus more on other energy sources. The renewable energy sources (solar, wind and hydro) have been present in nature, but the technology to harvest these energies have always been relatively expensive until recently. The biggest advantage of using renewable energy sources is the fact that these energy sources will never run out and they also do not pollute the environment as their more conventional counterparts. With more research being conducted into better ways of storing the power trapped from the renewable energy sources and the relative difficulty of obtaining the ever-depleting conventional energy sources, the future for renewable energy sources definitely looks better than at any time in the past
56

Investigation of an emulsion/dispersion solar thermal energy storage system

Cease, Michael Edwin January 1980 (has links)
No description available.
57

An Adaptive Control Algorithm For Maximum Power Point Tracking for Wind Energy Conversion Systems

Hui, Joanne 16 December 2008 (has links)
Wind energy systems are being closely studied because of its benefits as an environmentally friendly and renewable source of energy. Because of its unpredictable availability, power management concepts are essential to extract as much power as possible from the wind when it becomes available. The purpose of this thesis is to presents a new adaptive control algorithm for maximum power point tracking (MPPT) in wind energy systems. The proposed control algorithm allows the generator to track the optimal operation points of the wind turbine system under fluctuating wind conditions and the tracking process speeds up over time. This algorithm does not require the knowledge of intangible turbine mechanical characteristics such as its power coefficient curve, power characteristic or torque characteristic. The algorithm uses its memory feature to adapt to any given wind turbine and to infer the optimum rotor speeds for wind speeds that have not occurred before. The proposed algorithm uses a modified version of Hill Climb Search (HCS) and intelligent memory to implement its power management scheme. This algorithm is most suitable for smaller grid or battery connected wind energy systems. PSIM simulation studies have been done to confirm the effectiveness of the proposed algorithm. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2008-12-15 20:47:44.884
58

General design of a solar power system using the principle of energy availability

Lee, Chien Kuo 12 1900 (has links)
No description available.
59

Analysis of state major facility siting processes with recommendations for Montana /

Hart, Kevin Jay, January 1980 (has links)
Thesis (masters)--Montana State University. / Includes bibliographical references.
60

Mathēmatika protypa energeiakōn zētēseōn kai epharmoges

Samouēlidēs, Emmanouēl-Iēsous. January 1979 (has links)
Thesis--Ethnikon Metsovion Polytechneion, 1979. / Summaries in Greek and English. Includes bibliographical references (p. 303-310).

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