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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

Development of an integrated building load and ground source heat pump model to assess heat pump and ground loop design and performance in a commercial office building

Blair, Jacob Dale 07 October 2014 (has links)
Ground source heat pumps (GSHPs) offer an efficient method for cooling and heating buildings, reducing energy usage and operating cost. In hot, arid regions such as Texas and the southwest United States, building load imbalance towards cooling causes design and performance challenges to GSHP systems in residential and commercial building applications. An integrated building load and GSHP model is developed in this thesis to test approaches to reduce GSHP cost, to properly size ground heat exchanger (GHEX) installations and to offer methods to improve GSHP performance in commercial buildings. The integrated model is comprised of a three-story office building, heat pumps, air handling system and a GHEX. These component models were integrated in the Matlab® Simulink® modeling environment, which allows for easy model modification and expansion. The building-load model was developed in HAMBASE, which simulates the thermal and hygric response of each zone in the building to external weather and internal loads. The building-load model was validated using the ASHRAE 140-2007 Standard Method of Test and with results from EnergyPlus. The heat pump model was developed as a performance map, based on data commonly provided by heat pump manufacturers. This approach allows for easy expansion of the number and type of heat pump models supported. The GHEX model was developed at Oklahoma State University and is based on Eskilson’s g-function model of vertical borehole operation. The GHEX model accurately represents the interaction between boreholes and the ground temperature response over short and long time-intervals. The GHEX model uses GLHEPRO files for parameter inputs. Long time-interval simulations of the integrated model are provided to assess the sensitivity of the GSHP system to various model parameters. These studies show that: small changes in the total GHEX length reduce system cost with minimal impact on performance; increased borehole spacing improves system performance with no additional cost; supplemental heat rejection reduces installation costs and improves system performance; industry-recommended design cutoff temperatures properly size the GHEX system; and, while cooling is the greatest contributor to operating cost in the southwest and southcentral United States, heating is the limiting design case for GHEX sizing. / text
12

A technical and economic feasibility study for the integration of GSHP technology in the Christchurch rebuild

Bustard, Samuel Kent January 2014 (has links)
Mr Wayne Tobeck, Director of Southrim Group (SRG), sponsored this 2013 MEM Project titled; A Technical and Economic Feasibility Study for the Integration of GSHP Technology in the Christchurch Rebuild. Following the recent Christchurch earthquakes, a significant amount of land has become too unstable to support traditional building foundations. This creates an opportunity to implement new and unique foundation designs previously unconsidered due to high costs compared to traditional methods. One such design proposes that an Injection Micro-Piling technique could be used. This can also be coupled with HVAC technology to create a Ground Source Heat Pump (GSHP) arrangement in both new buildings and as retrofits for building requiring foundation repair. The purpose of this study was to complete a feasibility study on the merits of SRG pursuing this proposed product. A significant market for such a product was found to exist, while the product was also found to be technically and legally feasible. However, the proposed product was found to not be economically feasible with respect to Air Source Heat Pumps due to the significantly higher capital and installation costs required. Further analysis suggests GSHPs may become more economically attractive in operating temperatures lower than -9oC, though the existence of markets with this climate in NZ has not been studied. It is therefore suggested that SRG do not proceed with plans to develop a GSHP coupled foundation solution for the Christchurch rebuild.
13

Potential of Geothermal Energy in India

Sharma, Prajesh January 2019 (has links)
In this research paper, review of world geothermal energy production and their capacity is shown. Here, a research is conducted to know the potential and possibility of geothermal energy in India. All the geothermal province with their geographical locations are shown and a brief calculation is conducted in order to show the potential of the particular province. As India is having the low temperature geothermal fields, binary geothermal plants are used for this analysis and results are calculated by using R134a as a working fluid at different temperatures. The results are sufficient to prove the potential of geothermal energy in India.  Importance of Ground Source Heat Pump (GSHP) and power savings by its contribution over traditional heating and cooling methods is shown statistically. 9 different states of India are divided by their climatic condition, severe winter and moderate winter to calculate the heat demand in those states. Also, for the cold demands these states are considered to be same as per the climatic situation in summer. Then, comparison is done between GSHP and the traditional heating and cooling systems. The result shows the drastic power saving by using GSHP for space heating as well as cooling, over electric heater and air conditioner respectively.
14

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
<p>2008-05-26</p><p>Bedrock heat as an energy source</p><p>The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.</p>
15

Bergvärme som energikälla

Back, Natalii January 2008 (has links)
2008-05-26 Bedrock heat as an energy source The sun has warmed up the bedrock and this heat can be used for warming up houses. Approximately 100 – 200 meters down in the bedrock the temperature of the heat is stable. This is a source of energy that can be used by installing a heat pump system. The ground source heat pumps are low maintenance and can last for many years. There is also a pollution risk for the groundwater and therefore the wells in the area. Before the ground source heat pump can be installed the municipality need to give permission, according to the environmental code. To install the system without permission is a crime against the environmental code. A requirement when applying for permission to install the heat pump system is to get the neighbours to agree with the place for the bore hole. The neighbour can appeal against the environmental and health authorities’ decision to give permission to install the ground source heat pump system. However there needs to be more research done regarding the environmental effects that may occur in the future, if the ground source heatpump system continues to increase as rapidly as today.
16

Simulation of Photovoltaic Panel Production as Complement to Ground Source Heat Pump System

Badri, Seyed Ali Mohammad January 2013 (has links)
This master thesis presents a new technological combination of two environmentally friendly sources of energy in order to provide DHW, and space heating. Solar energy is used for space heating, and DHW production using PV modules which supply direct current directly to electrical heating elements inside a water storage tank. On the other hand a GSHP system as another source of renewable energy provides heat in the water storage tank of the system in order to provide DHW and space heating. These two sources of renewable energy have been combined in this case-study in order to obtain a more efficient system, which will reduce the amount of electricity consumed by the GSHP system.The key aim of this study is to make simulations, and calculations of the amount ofelectrical energy that can be expected to be produced by a certain amount of PV modules that are already assembled on a house in Vantaa, southern Finland. This energy is then intended to be used as a complement to produce hot water in the heating system of the house beside the original GSHP system. Thus the amount of electrical energy purchased from the grid should be reduced and the compressor in the GSHP would need fewer starts which would reduce the heating cost of the GSHP system for space heating and providing hot water.The produced energy by the PV arrays in three different circuits will be charged directly to three electrical heating elements in the water storage tank of the existing system to satisfy the demand of the heating elements. The excess energy can be used to heat the water in the water storage tank to some extent which leads to a reduction of electricity consumption by the different components of the GSHP system.To increase the efficiency of the existing hybrid system, optimization of different PV configurations have been accomplished, and the results are compared. Optimization of the arrays in southern and western walls shows a DC power increase of 298 kWh/year compared with the existing PV configurations. Comparing the results from the optimization of the arrays on the western roof if the intention is to feed AC power to the components of the GSHP system shows a yearly AC power production of 1,646 kWh.This is with the consideration of no overproduction by the PV modules during the summer months. This means the optimized PV systems will be able to cover a larger part of summer demand compared with the existing system.
17

Development of an integrated building load-ground source heat pump model as a test bed to assess short- and long-term heat pump and ground loop performance

Gaspredes, Jonathan Louis 08 February 2012 (has links)
Ground source heat pumps (GSHP) have the ability to significantly reduce the energy required to heat and cool buildings. Historically, deployment of GSHP's in the cooling-dominated Texas and Southwest region has been significantly less than in other regions of the United States. The long term technical and economic viability of GSHPs in arid regions such as Texas has been questioned due to failures of ground loop heat pump systems by early adopters. A proposed solution is to include a supplemental heat rejection (SHR) device to help offset the unbalanced ground loads. An integrated building load-ground source heat pump model is developed in this thesis and is designed to be a test bed for potential SHR devices. The model consists of discrete component models that can be mixed and matched to represent various types of buildings and ground source heat pumps. One of the unique features of the integrated model is the use of the Simulink/Matlab environment. This environment allows the user to develop component models that take advantage of the built-in functionality of Matlab and Simulink. Another unique feature is the full coupling of the building load, heat pump, and ground loop at every time step. The building load, heat pump, and ground loop models were chosen to allow for short time step simulations, which allows for a range of dynamic response times to be modeled and for different heat pump/SHR control methods to be explored. The integrated model can be used on any computer that has the Matlab and Simulink software. The building load model used, called HAMBASE, can model both residential and commercial buildings. HAMBASE was validated using the ASHRAE 140-2007 standard. The heat pump model uses readily available data provided by GSHP manufacturers to accurately model operation across a wide range of input conditions. The vertical borehole ground loop model, developed at Oklahoma State University, is based on Eskillson's g-function model, but included a one-dimensional numerical model to calculate the short term thermal response of the borehole and ground. The ground loop model utilizes GLHEPRO, a ground loop sizing and simulation tool, to create the required parameter files. Using the integrated building load-ground source heat pump model, a model of a single family house with a ground source heat pump was developed. The house model was validated by the results from eQuest and GELHPRO. A series of sensitivity studies were completed to determine dominant factors affecting the use of GSHPs in Texas and the Southwest regions of the United States. The results show that the life of a vertical borehole can be significantly extended/cut short if the ground parameters are properly/not properly designed prior to ground loop sizing. / text
18

Computer modelling and simulation of geothermal heat pump and ground-coupled liquid desiccant air conditioning systems in sub-tropical regions

Lee, Chun-kwong. January 2008 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 177-192) Also available in print.
19

Simulation of an energy efficient single-family house in the area of Smedjebacken to meet Miljöbyggnad’s Gold House energy category requirements

Daroudi, Parham January 2018 (has links)
Since the building construction area is accounted for high share of energy usage (36 %) in Europe, there is high demand to pay attention to this area accurately. Sweden which is one of the pioneer countries in terms of building energy efficiency plans to reduce this value to 50 % by 2050. To reduce this value there is a need to define a mandatory guideline for builders by the government. So national board of housing, building and planning (Boverket) were given responsibility to define these regulations for builders and house owners. Parallel with that Swedish green building council developed a certification considering the buildin g’s energy demand, indoor air climate and environmental impact of building called Miljöbyggnad. While all the existing and new buildings following Boverket’s regulations meet this certification’s lowest limitations, some ambitious builders tend to fulfil its highest level of limitations called Gold level. This study aimed to design a house in the area of Smedjebacken to meet Miljö byggnad’s gold house’s energy category requirements. To meet the mentioned requirements several parametric studies regarding insulation thickness, windows assembly, heating and ventilation system are done via simulation software called TRNSYS. The result of testing several models show that although windows assembly does not affect this building ’s energy demand very much, other parameters such as insulation ’s thickness and type of heating system have a key role. In addition, a parametric study regarding the impact of thermal mass on the building energy demand is performed. The result shows that the effect of removed massive wood is compensated by replaced additional mineral wool insulation. In conclusion it is concluded that a single family house located in a cold climate like Smedjebacken using district heating cannot meet Miljöbyggnad’s gold level criteria without help of heat recovery ventilation. Furthermore, building with ground source heat pump as its heating system can meet Miljöbyggnad’s principals easier than those having district heating. In this case building with 200 mm insulation thickness even with exhaust air ventilation meets certification principals easily.
20

L'adoption de géothermique à des échelles multiples en Amérique du Nord / The adoption of ground source heat pumps at multiple scales in North America

Jensen, Thor 11 December 2015 (has links)
En Amérique du Nord, le chauffage de l'espace, l'eau chaude, et l'utilisation de la climatisation énergie secondaire plus que toute autre activité au sein de bâtiments, émettant ainsi la majorité des gaz périmètres 1 et 2 serre (GES). La pompe à chaleur géothermique (PCG) utilise un tiers de l'énergie des technologies traditionnelles de fournir un espace de services d'eau chaude et de climatisation. Bien géothermique est une technologie bien établie, les économies d'énergie et les émissions de GES ne sont pas traduits dans leur adoption généralisée. Les mesures de politique publique et les incitations financières adoptées pour promouvoir PCG ont échoué à conduire à une large adoption ou de réduire les coûts. Cette thèse examine l'adoption de pompes à chaleur géothermiques en réponse aux politiques de soutien parmi les adopteurs résidentiels, institutionnels, et la ville-échelle. Données au niveau détaillé du site et des panneaux permettent expériences naturelles sur la réponse des adoptants résidentiels au Canada et aux États-Unis à l'évolution des incitations. À des échelles supérieures, les procédures réglementaires relatives à l'offre de services de l'énergie thermique (TES) a fourni une étude de cas pour l'analyse des modèles d'utilité pour financer géothermique pour les clients commerciaux et institutionnels. Au Canada et aux États-Unis, les incitations financières ont échoué à soutenir l'adoption de la pompe à chaleur géothermique à travers ou après la période de la subvention pour les ménages résidentiels. Pas plus que les incitations conduisent à une diminution des prix dans le temps. Problèmes de resquillage au Canada et une incapacité à faire des incursions dans les zones desservies par le gaz naturel ont brin technologie géothermique. En outre, le coût en capital de pompes à chaleur géothermiques en résulte un coût de cycle de vie plus élevé que la plupart des solutions de rechange. Les avantages de l'économie à l'échelle d'incitations financières pour les pompes à chaleur géothermiques sont limitées au Canada, où la plupart des pompes à chaleur sont importés. TES fournissent innovations convaincantes pour combler les obstacles à des échelles supérieures. TES surmonter équilibrer les contraintes de bilan sur la dette commune aux organisations du secteur public par le financement de biens d'équipement et de rénovation que les paiements de services publics. TES peut surmonter les contraintes de capitaux rencontrés par les développeurs en finançant des équipements à l'intérieur du bâtiment en réduisant les coûts de construction. Cependant, notre étude des marchés publics de cas révèle TES être une approche coûteuse dans le long terme. Les perspectives de cette recherche sont traduits dans les meilleures pratiques et des conseils stratégiques pour améliorer la passation des marchés, accroître la sensibilisation, et aligner les incitations pour une plus grande efficacité. / In North America, space heating, hot water, and air conditioning use more secondary energy thanany other activity within buildings, thus emitting the majority of scope 1 and scope 2 GreenhouseGases (GHG). The Ground Source Heat Pump (GSHP) uses one-third the energy of traditionaltechnologies to provide space conditioning and hot water services.While GSHP is a well-established technology, the energy savings and lower GHG emissionshave not translated into their widespread adoption. Public policy measures and financialincentives adopted to promote GSHP have failed to lead to broad adoption or lower costs. Thisthesis examines the adoption of GSHP in response to supportive policies among residential,institutional, and city-scale adopters.Detailed site-level and panel data permit natural experiments on the response of residentialadopters in Canada and the US to changing incentives. At higher scales, regulatory proceedingsconcerning the offering of Thermal Energy Services (TES) has provided a case study for analysisof utility models to finance GSHP for commercial and institutional clients.In Canada and the US, financial incentives failed to sustain the adoption of GSHP throughout orafter the period of subsidy among residential households. Neither did incentives lead to adecrease in price over time. Free-ridership problems in Canada and an inability to make inroadsto areas served by natural gas have stranded GSHP technology. Further, the capital cost ofGSHP results in a higher lifecycle cost than most alternatives. The economy-wide benefits offinancial incentives for GSHP are limited in Canada, where most heat pumps are imported.iiiTES provide compelling innovations to bridge barriers at higher scales. TES overcome balancesheet constraints on debt common to public sector organizations by financing capital equipmentand renovations as utility payments. TES can overcome capital constraints faced by developersby financing equipment inside the building lowering construction costs. However, our casestudy of public procurement reveals TES to be a costly approach in the long run. The insightsfrom this research are translated into best practices and policy advice to improve contracting,increase awareness, and align incentives for greater efficiency.

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