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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.
11

ENERGY AUDIT OF HIG STUDENT HOSTEL

Yao, Li January 2014 (has links)
Nowadays in the world, energy usage effectiveness has always been an issue which blocks people’s development. How to effectively use the energy is becoming more and more important. Energy audit can appraise the energy usage condition of a building, and come up with improvement advices through systematic calculation and analysis the existing problems and reasons for energy wastes, in order to bring the object of effective usage of energy into reality. HiG student hostel 23 is situated in Gävle, a coastal city in the east of Sweden. There are three floors in Hostel 23, the first and second floor have 18 single rooms, 4 double rooms and 2 communal kitchens and the third floor is storeroom. The aim of this thesis is to explore indoor climate and energy use for this student hostel and find out the reason of the low temperature inside the room, seeking some ways to improve the thermal comfort inside the building during winter conditions. First, collect date from every part in energy balance by measurement and interview with administrator, then calculate and analyze the data. At last, the whole energy balance can be estimated. Through analyzing the whole energy balance, the suggestion is to change the window type and design a new ventilation system operating plan. Through the optimization, energy loss is reduced, and about 10% of the energy is preserved. Besides this, the building infiltration loss is too high through this energy audit; it states there still exists some problems. If these problems can be solved, it will be helpful to keep a good thermal comfort inside the building.
12

An Energy Audit of Kindergarten Building in Vallbacksgården

Liu, Xiaojing, Zhang, Taoju January 2015 (has links)
Energy consumption rises continuously every year. Globally, buildings count for half of electricity consumption and 20%-40% of total energy consumption. Building energy sector consumed 40% of total energy use in Sweden. The vital of reduce energy consumption is to enhance building efficiency. This energy audit work investigates how energy consumes of kindergarten building in Vallbacksgården. Then give out cost effective suggestions to improve energy efficiency for object building. The result shows total amount of energy input of the building is equal to 241.9 MWh. While district heating takes the largest part of energy input that correspond to 188.9 MWh (78%), and cost around 123500 Kr annually. Furthermore, energy 38.0 MWh (16%) is contributed by solar radiation, which becomes second largest source of energy input. Finally, internal heat generation is the smallest contributor of energy input which counts 15.0 MWh (6%). For energy output, majority of heat loss is leaded by transmission losses. It cost 190.4 MWh per year that shares 79% of total energy output. Nature ventilation losses of object building shares 17% of total heat output which is 41.7 MWh. Mechanical ventilation and hot tap water have energy consumption with 7.8 MWh and 2.0 MWh respectively. They take rest 4% of total energy output. According to the finding, several reasonable suggestions will be given. Firstly, for the costless solution, decreasing indoor temperature 1℃ or 2 ℃ is able to reduce heating demand 9.0 MWh or 18.1 MWh annually. It will reduce CO2 emission 131859g- 266070 g, and save 5274 – 10642 SEK per year. Secondly, substitute district heating systems by ground source heat pump is an environmental solution. Using ground source heat pump has priority of environment, which lower CO2 emission 1909200 g/year and save 68262 SEK/year by analyze. Investment for this solution is 979000 SEK and the payback time takes 14.3 year. Replace old windows is a moderate solution of cost. Substitution by using energy glass can reduce 20.9 MWh heating demand and 307377 g CO2 every year. New energy glass windows can cut 13591 SEK for district heating every year. The renovate investment and payback time are more than 159732 SEK and 11.8 year respectively.
13

ENERGY AUDIT of GEFLE VAPEN

Sui, Chen January 2009 (has links)
<p>The energy audit is a very interesting and complex work. The building energy audit is defined as a process to evaluate where the energy used in the building structure and to identify the opportunities of reduce energy consumptions. In this paper, it is a first time detailed study of energy audit for me. In this research, the object is to find is it necessary to improve the ventilation systems. So the first step is to estimate how much energy consumed in the building and to find out the saving potential.The major mission in this thesis is that to make a basic energy audit which is include the heat losses from the building and the heat supply in the building. The major heat losses are transmission losses, ventilation losses, heat losses from hot tap water and infiltration losses. In this project the first three types of heat losses could be find out by some useful methods but the infiltration losses is hard to measure. On the other side, the heat supply are composed by district heating , free heating from people inside, free heating from electricity applications and sun irradiation.To make an accurate and complete energy audit is essential for finding out where the energy consumption could be reduced. And this is what I am going to do in this thesis work.</p>
14

Impact assessment of energy conservation strategies in swine barns through benchmarking and building simulation

Navia, Eleonor 19 November 2008
Energy input is vital in every swine operation as it directly affects production performance and overall profitability. With the increasing trend in energy prices and feed costs, the swine industry needed to find ways to improve energy use efficiency in their operations in order to reduce overall cost of production. The goals of this study were to gather benchmark information on current energy usage in swine barns through survey and energy audit, and evaluate different energy-saving measures through building simulation.<p> The results of the survey showed that the average electricity and gas cost was $6.50/head for farrow-to-finish barns, $1.70/head for grow-finish barns, $0.59/head for nursery and $1.95/head for farrow-wean barns. Significant difference (P<0.05) in energy usage within the same type of operation was observed, implying significant opportunities to improve energy use practices in some barns to reduce overall energy costs.<p> The results of the barn monitoring showed that the average daily electricity consumption during summer for farrowing, nursery, grow-finish and gestation room was 3.79 kWh/head (16 sows); 0.12 kWh/head (226 pigs); 0.14 kWh/head (551 pigs) and 0.33 kWh/head (349 sows); respectively. During winter, the average daily electricity consumption for farrowing, nursery, grow-finish and gestation room was 3.92 kWh/head (15 sows); 0.14 kWh/head (227 pigs); 0.09 kWh/head (521 pigs) and 0.22 kWh/head (322 sows); respectively. Highly negative correlation (range from -0.6 to -0.9) was observed between the fan energy consumption and gas concentration of H2S, NH3 and CO2 during summer. This implied that reducing ventilation rate was not a sound option to reduce energy consumption.<p> A simulation model was developed using the principle of heat transfer and thermodynamics to evaluate various energy-conservation measures through building simulation. Applying energy conservation strategies to lighting, creep heating, recirculation fans, exhaust fans, feed motor and heat recovery, an average annual savings of 25,957 kWh (43 kWh/sow); 47,391 kWh (79 kWh/sow); 9,872 kWh (16 kWh/sow); 118,890 kWh (198 kWh/sow); 1,846 kWh (3 kWh/sow); and 74,952 m3 (125 m3/sow) can be achieved, respectively. The outcome of this research project will help pork producers in managing the use of energy in their operations more efficiently, thereby reducing overall energy costs. Additionally, the reduction of energy use across the industry would contribute to the reduction in greenhouse gas emissions associated with energy generation.
15

ENERGY AUDIT of GEFLE VAPEN

Sui, Chen January 2009 (has links)
The energy audit is a very interesting and complex work. The building energy audit is defined as a process to evaluate where the energy used in the building structure and to identify the opportunities of reduce energy consumptions. In this paper, it is a first time detailed study of energy audit for me. In this research, the object is to find is it necessary to improve the ventilation systems. So the first step is to estimate how much energy consumed in the building and to find out the saving potential.The major mission in this thesis is that to make a basic energy audit which is include the heat losses from the building and the heat supply in the building. The major heat losses are transmission losses, ventilation losses, heat losses from hot tap water and infiltration losses. In this project the first three types of heat losses could be find out by some useful methods but the infiltration losses is hard to measure. On the other side, the heat supply are composed by district heating , free heating from people inside, free heating from electricity applications and sun irradiation.To make an accurate and complete energy audit is essential for finding out where the energy consumption could be reduced. And this is what I am going to do in this thesis work.
16

Impact assessment of energy conservation strategies in swine barns through benchmarking and building simulation

Navia, Eleonor 19 November 2008 (has links)
Energy input is vital in every swine operation as it directly affects production performance and overall profitability. With the increasing trend in energy prices and feed costs, the swine industry needed to find ways to improve energy use efficiency in their operations in order to reduce overall cost of production. The goals of this study were to gather benchmark information on current energy usage in swine barns through survey and energy audit, and evaluate different energy-saving measures through building simulation.<p> The results of the survey showed that the average electricity and gas cost was $6.50/head for farrow-to-finish barns, $1.70/head for grow-finish barns, $0.59/head for nursery and $1.95/head for farrow-wean barns. Significant difference (P<0.05) in energy usage within the same type of operation was observed, implying significant opportunities to improve energy use practices in some barns to reduce overall energy costs.<p> The results of the barn monitoring showed that the average daily electricity consumption during summer for farrowing, nursery, grow-finish and gestation room was 3.79 kWh/head (16 sows); 0.12 kWh/head (226 pigs); 0.14 kWh/head (551 pigs) and 0.33 kWh/head (349 sows); respectively. During winter, the average daily electricity consumption for farrowing, nursery, grow-finish and gestation room was 3.92 kWh/head (15 sows); 0.14 kWh/head (227 pigs); 0.09 kWh/head (521 pigs) and 0.22 kWh/head (322 sows); respectively. Highly negative correlation (range from -0.6 to -0.9) was observed between the fan energy consumption and gas concentration of H2S, NH3 and CO2 during summer. This implied that reducing ventilation rate was not a sound option to reduce energy consumption.<p> A simulation model was developed using the principle of heat transfer and thermodynamics to evaluate various energy-conservation measures through building simulation. Applying energy conservation strategies to lighting, creep heating, recirculation fans, exhaust fans, feed motor and heat recovery, an average annual savings of 25,957 kWh (43 kWh/sow); 47,391 kWh (79 kWh/sow); 9,872 kWh (16 kWh/sow); 118,890 kWh (198 kWh/sow); 1,846 kWh (3 kWh/sow); and 74,952 m3 (125 m3/sow) can be achieved, respectively. The outcome of this research project will help pork producers in managing the use of energy in their operations more efficiently, thereby reducing overall energy costs. Additionally, the reduction of energy use across the industry would contribute to the reduction in greenhouse gas emissions associated with energy generation.
17

Energikartläggning av förskolan Smultronstället

Ahlund, Viktor January 2015 (has links)
Detta är ett examenarbete på grundnivå, 15 högskolepoäng. Examensarbetet är en energikartläggning med rekommenderade energieffektiviseringsåtgärder. Energikartläggningen är baserad på ett verkligt objekt vilket är en förskola i norra Gävle. Denna skola förvaltas av Gavlefastigheter.I Sverige går cirka 40 % av energianvändningen till bostäder och service. Därför finns det stora mängder energi att spara inom denna sektor. Ett bra sätt att utreda på vart energin går i en byggnad är att göra en energikartläggning.Energikartläggningen är utförd utifrån ritningar, verkliga mätningar, schablonvärden, antaganden och litteratur.Skolan har en beräknad energianvändning på 1239 MWh per år, detta är uppdelat på ventilation, transmissionsförluster och tappvarmvatten. Efter 3 beräknade effektiviseringsåtgärder blir energibesparingen sammanlagt 612 MWh detta är 49,4 %. De åtgärder som är beräknade är tilläggsisolering, byte av ventilation och byte av fönster. Att enbart byta till FTX-ventilation sparar 522 MWh detta är en besparing på 42,1 % av den totala energianvändningen och den rekommenderade åtgärden. / This report is an energy audit with recommended energy efficient solutions recommended made on a preschool in north Gävle. This preschool is administrated by Gavlefastigheter. In Sweden almost 40 % of Sweden’s energy supply goes to the housing and service sector. This means there is a lot of potential to save energy in this field. A good way to start saving energy in a building is to do an energy audit.This energy audit is made from blueprints of the building, real measurements, standard values, assumptions, and literature.The school has a calculated energy use of 1239 MWh per year; this is divided on ventilation, transmission losses and hot tap water. A calculation with energy efficient solutions makes a total of 612 MWh or 49, 4 % in saved energy. The energy efficient savings calculated are new windows, additional insulation and changed ventilation. To only change the ventilation made for an energy saving of 522 MWh which is 42, 1 % from the total energy use in the building. To change the ventilation to an FTX-system is the recommended change to be made.
18

Energy Audit and Renovation Proposal for a joint Ventilation System of Five Commercial Premises

Li, Yufang January 2014 (has links)
Energy saving is a highly concerned topic in the developing countries. To achieve a desirable living and working condition for inhabitants while consuming minimum amount of energy, more and more efforts, new technologies are developed and invested in the different industries by countries. It has been discussed that energy use in the building sectors is intensive and has the largest share in the total energy supply. Therefore, a growing number of companies and institutions are either required or voluntary to take energy efficiency measures once a year or more to identify current energy use, as well as the opportunities for energy efficiency improvement. One of the energy efficiency measures is energy audit. This report is aiming at pinpointing the current energy consumption for a joint ventilation system used by five premises in downtown Gävle, Sweden. The building company is planning a renovation for the ventilation system, including a cut down of energy supply while improving thermal comfort by providing adequate ventilation. The main object area is a restaurant, which consumes most energy supply. During the measurements, three sets of equipment (TSI VelociCalc plus, SWEMA FLOW 230 and TSI-AccuBALANCE) were used to collect air flow and temperature data. The results indicate that the current energy use for the joint ventilation system during a year is around 50438 kWh, using recommended ventilation rates; while it can be reduced to 34737 kWh. For the restaurant, the required ventilation rate is 1204 l/s to provide fresh air constantly if it is over 150 people and give ventilation according the standard: 7 l/s p 0.35 l/s m2. The current ventilation rate is only 312 l/s, thus clearly failing to comply with the standard. One viable method for providing enough ventilation rate and at the same time without wasting energy is to install CO2 detector, which regulates the ventilation rate according to the level of CO2 concentration. The studied shops have instead very high ventilation rates in the current system; though this provides good air quality, the energy is wasted unnecessarily.
19

Energy audit in Fridhemsskolan : A preschool in Gävle municipality

Balogun, Kazeem Ayinde January 2018 (has links)
This thesis is about the energy audit in Fridhemsskolan which is an educational facility. Fridhemsskolan is a preschool for children in Gävle municipality for children up to the age of six years and comprise of nine buildings in total. The project begins with an energy survey on the school facilities which ranges from checking the ventilation system, lightning system, number of occupants, equipment’s types and so on. The next step was to use a simulation program software called indoor climate and energy (IDA ICE) to create the base model for the building and input the data collected during the energy survey directly into the software and simulate it for a period of one year. After creating the base model, the total electricity use of the building was around 89 MWh/year while the district heating was 157 MWh/year.The energy conservation opportunities in Fridhemsskolan for the building was divide into two categories and these are referred to as non-retrofitting (no or minimal cost) and retrofitting (with cost) recommendations. The non-retrofitting involves reducing the indoor temperature and with this approach; the district heating consumption was reduced to 147.6 MWh/year which amount to 9.34 MWh/year in savings for the district heating while the electricity consumption was reduced to 86.4 MWh/year which amount to 2.6 MWh/year in savings for the electricity.Retrofitting (with cost) recommendations involves looking at the base model and see where some improvements can be carried out. In this research, the roof of the building has more energy losses and retrofitting with cost analysis was performed on that part of the building envelope.After retrofit, the district heating consumption was reduced to 142 MWh/year which is about 15 MWh/year in saving for the district heating while the electricity consumption was reduced to 26 MWh/year which also amount to 63 MWh/year saving in electricity consumption. The reason for this sharp decrease in the electrical consumption was because, the electrical radiators in the base model of the building was replaced with ideal heaters that uses district heating as the energy carrier and 170 mm of mineral wool was also added to the roof.Finally the research further looks at the thermal comfort and the indoor air quality of the occupants in the building by analysing the data on both thermal comfort and the indoor air quality to see if the value obtained are within the acceptable range. In most cases the value is within the acceptable range like in the case of carbon dioxide (CO₂) concentration in theiiioccupied zone, the value obtained after reducing the indoor temperature was less than 1000 parts-per-million (ppm) and that shows that the carbon dioxide (CO₂) concentration is within an acceptable level in the room. The thermal comfort of the occupants in the occupied zone was within the acceptable limit. However, lowering indoor temperature increases the PPD for both buildings. The percentage of the total occupant hours with thermal dissatisfaction increases to 13% from 14 % for Hus 9 and from 13% to 15% for Hus (4-8).
20

Energy audit of an industrial facility,Hagby waste management plant

Kunytsia, Maksym January 2016 (has links)
In order to answer modern challenges, which come from increasing needs in energy forprivate persons and industries as well as in order to decrease negative environmentalimpacts, caused by the processes of energy generation, it is important to constantly searchfor untapped energy efficiency potential. Moreover, nowadays, energy efficiency hasbecome one of the prerequisites of successful market competitiveness for any type ofindustry on local and global levels.An energy audit is an instrument, which can be used for understanding how the energy isused and identify possible energy-saving opportunities. It can be applied to a facility as awhole, as well as individually to equipment, system(s) or process(es). Moreover, energysaving measures can be both cross-cutting and sector-specific.The purpose of this project was to conduct a detailed energy audit of the Hagby wasterecycling plant and to identify beneficial energy saving opportunities from economic,environmental and social perspectives.In the frames of a preliminary energy audit 10 focus areas for further analysis wereidentified. For every area a baseline assessment of the current energy performance wasconducted, possible energy management opportunities were identified and evaluated aswell as results of each analysis were summarized. According to the results of the study, with the implementation of the suggestions, whichrequire no, low or medium investments it is possible to save 3,2% of the energy per year,which corresponds to 76 846 kWh. Energy consumption can further be decreased byimplementing measures, which need high initial financial investment. In that case totalsavings will be 468 846 kWh or 19,4% of total annual energy consumption. Additionalenergy might be saved just by introducing energy housekeeping measures. Finally,implementation of all the proposed EMO can bring 14,46 tons of 2 CO savings annually.Additional benefits of implementing the energy saving opportunities come from decreasingenvironmental impacts, improving working conditions of the plant employees and higherenergy security at the plant.The results of the energy audit can be a solid base for establishing an energy managementprogram at the plant, which will include performance targets, required resources and aclear procedure of realization of improvements. However, since some of the calculations inthe current study are based on various assumptions, after the company forms the energymanagement program, it is necessary to invite experts from industry in order to giveaccurate calculations for each of the focus areas.

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