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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.
1

Impact of ASHRAE standard 189.1-2009 on building energy efficiency and performance

Blush, Aaron January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / The purpose of this report is to provide an introduction to the new ASHRAE Standard 189.1-2009, Standard for the Design of High-Performance Green Buildings. The report will include an overview of the standard to detail what the purpose, scope and requirements for high-performance buildings will be. The entire standard will be overviewed, but the focus of this paper is in the areas of energy efficiency and building performance. Next, the report will examine further impacts that the standard will have on the building design and construction industry. Chapter 3 includes the impact on other standards, specification writing and coordination of the design and construction teams. A case study of an office building is performed to compare a baseline building meeting ASHRAE Standard 90.1 to a building meeting the minimum standards of ASHRAE Standard 189.1. The case study compares the total annual energy use of the two projects to determine an expected energy savings. Based on this information, recommendations about the new standard will be discussed. Universities and government entities should require ASHRAE Standard 189.1 for new construction projects, to show willingness to provide sustainability in buildings. Finally, conclusions about how the standard will change and impact industry will be addressed. These conclusions will include issues with adopting ASHRAE Standard 189.1 as code as well as discussion on the LEED rating system.
2

Risk Management in Sustainable Projects in the Construction Industry : Cases of Swedish Companies

Apine, Anete, Escobar Valdés, Francisco José January 2017 (has links)
Sustainable construction projects are expanding in the market and green codes andstandards are advancing giving the ground for development of technology and materialsapplied. With every new material and technology utilised in the field, also risks aregrowing. The importance of risk management in sustainable construction projects isthus increasing and more experience and expertise is needed. So, the purpose of thisthesis is to examine and gain deeper understanding of project related risks in sustainableconstruction projects in Swedish companies operating in built environment. It is crucialto gain knowledge of good practices within the industry to be able to propose furtherinvestigation of the subject that could improve the existing risk management andsustainable construction project goals.This thesis examines the existing theory of the risk management process and sustainableprojects by shedding light on the trends within the construction industry. The intentionof the thesis is to add value to the existing gap in the theory that suggests thatconstruction industry is exposed to more risks and uncertainty than perhaps otherindustries, and that introducing sustainability adds more uncertainties and risks. Thisphenomenon is claimed to be due to the lack of knowledge and experience in the areaand, thus, practitioners seek for new ways how to tackle the arising issues. This thesisattempts to display how Swedish companies who are working with green and highperformance buildings identify and deal with risks.Two Swedish companies operating in built environment were chosen in order toinvestigate different ways of dealing with risks and the trend of sustainability inconstruction. Those in charge of risk and sustainability within the companies wereinterviewed applying semi-structured interviews and additional information wasgathered through multiple sources, such as annual reports, web pages and otherdocuments. This thesis has exploratory and qualitative research design and appliesabductive approach for the purpose and the nature of phenomena.The findings showed the different tools how risk management is applied in thecompanies and how it is related to the risks faced in green building construction. Theresults showed the importance of tools applied tackling sustainable construction projectsthat companies have applied and added to their processes in order to manageuncertainties that could occur if these processes were not implemented. As regards thegeneralisability towards findings, there still could be added more companies and futureresearch could imply also maturity of the companies to make findings more precise.However, after consideration of the processes learnt from companies, the proposedmodel for achievement of successful sustainable construction projects can be followedand applied in other companies operating in this industry.
3

The DC Nanogrid House: Converting a Residential Building from AC to DC Power to Improve Energy Efficiency

Jonathan Ore (10730034) 05 May 2021 (has links)
<p></p><p>The modern U.S. power grid is susceptible to a variety of vulnerabilities, ranging from aging infrastructure, increasing demand, and unprecedented interactions (e.g., distributed energy resources (DERs) generating energy back to the grid, etc.). In addition, the rapid growth of new technologies such as the Internet of Things (IoT) affords promising new capabilities, but also accompanies a simultaneous risk of cybersecurity deficiencies. Coupled with an electrical network referred to as one of the most complex systems of all time, and an overall D+ rating from the American Society of Civil Engineers (ASCE), these caveats necessitate revaluation of the electrical grid for future sustainability. Several solutions have been proposed, which can operate in varying levels of coordination. A microgrid topology provides a means of enhancing the power grid, but does not fundamentally solve a critical issue surrounding energy consumption at the endpoint of use. This results from the necessary conversion of Alternating Current (AC) power to Direct Current (DC) power in the vast majority of devices and appliances, which leads to a loss in usable energy. This situation is further exacerbated when considering energy production from renewable resources, which naturally output DC power. To transport this energy to the point of application, an initial conversion from DC to AC is necessary (resulting in loss), followed by another conversion back to DC from AC (resulting in loss).</p> <p> </p> <p>Tackling these losses requires a much finer level of resolution, namely that at the component level. If the network one level below the microgrid, i.e. the nanogrid, operated completely on DC power, these losses could be significantly reduced or nearly eliminated altogether. This network can be composed of appliances and equipment within a single building, coupled with an energy storage device and localized DERs to produce power when feasible. In addition, a grid-tie to the outside AC network can be utilized when necessary to power devices, or satisfy storage needs. </p> <p> </p> <p>This research demonstrates the novel implementation of a DC nanogrid within a residential setting known as <i>The DC Nanogrid House</i>, encompassing a complete household conversion from AC to DC power. The DC House functions as a veritable living laboratory, housing three graduate students living and working normally in the home. Within the house, a nanogrid design is developed in partnership with renewable energy generation, and controlled through an Energy Management System (EMS). The EMS developed in this project manages energy distribution throughout the house and the bi-directional inverter tied to the outside power grid. Alongside the nanogrid, household appliances possessing a significant yearly energy consumption are retrofitted to accept DC inputs. These modified appliances are tested in a laboratory setting under baseline conditions, and compared against AC equivalent original equipment manufacturer (OEM) models for power and performance analysis. Finally, the retrofitted devices are then installed in the DC Nanogrid House and operated under normal living conditions for continued evaluation.</p> <p> </p> <p>To complement the DC nanogrid, a comprehensive sensing network of IoT devices are deployed to provide room-by-room fidelity of building metrics, including proximity, air quality, temperature and humidity, illuminance, and many others. The IoT system employs Power over Ethernet (PoE) technology operating directly on DC voltages, enabling simultaneous communication and energy supply within the nanogrid. Using the aggregation of data collected from this network, machine learning models are constructed to identify additional energy saving opportunities, enhance overall building comfort, and support the safety of all occupants.</p><br><p></p>
4

Prioritizing Residential High-Performance Resilient Building Technologies for Immediate and Future Climate Induced Natural Disaster Risks

Ladipo, Oluwateniola Eniola 14 June 2016 (has links)
Climate change is exacerbating natural disasters, and extreme weather events increase with intensity and frequency. This requires an in-depth evaluation of locations across the various U.S. climates where natural hazards, vulnerabilities, and potentially damaging impacts will vary. At the local building level within the built environment, private residences are crucial shelter systems to protect against natural disasters, and are a central component in the greater effort of creating comprehensive disaster resilient environments. In light of recent disasters such as Superstorm Sandy, there is an increased awareness that residential buildings and communities need to become more resilient for the changing climates they are located in, or will face devastating consequences. There is a great potential for specific high-performance building technologies to play a vital role in achieving disaster resilience on a local scale. The application of these technologies can not only provide immediate protection and reduced risk for buildings and its occupants, but can additionally alleviate disaster recovery stressors to critical infrastructure and livelihoods by absorbing, adapting, and rapidly recovering from extreme weather events, all while simultaneously promoting sustainable building development. However, few have evaluated the link between residential high-performance building technologies and natural disaster resilience in regards to identifying and prioritizing viable technologies to assist decision-makers with effective implementation. This research developed a framework for a process that prioritizes residential building technologies that encompass both high-performance and resilience qualities that can be implemented for a variety of housing contexts to mitigate risks associated with climate induced natural hazards. Decision-makers can utilize this process to evaluate a residential building for natural disaster risks, and communicate strategies to improve building performance and resilience in response to such risks. / Ph. D.
5

An Adaptive Intelligent Integrated Lighting Control Approach for High-Performance Office Buildings

January 2015 (has links)
abstract: An acute and crucial societal problem is the energy consumed in existing commercial buildings. There are 1.5 million commercial buildings in the U.S. with only about 3% being built each year. Hence, existing buildings need to be properly operated and maintained for several decades. Application of integrated centralized control systems in buildings could lead to more than 50% energy savings. This research work demonstrates an innovative adaptive integrated lighting control approach which could achieve significant energy savings and increase indoor comfort in high performance office buildings. In the first phase of the study, a predictive algorithm was developed and validated through experiments in an actual test room. The objective was to regulate daylight on a specified work plane by controlling the blind slat angles. Furthermore, a sensor-based integrated adaptive lighting controller was designed in Simulink which included an innovative sensor optimization approach based on genetic algorithm to minimize the number of sensors and efficiently place them in the office. The controller was designed based on simple integral controllers. The objective of developed control algorithm was to improve the illuminance situation in the office through controlling the daylight and electrical lighting. To evaluate the performance of the system, the controller was applied on experimental office model in Lee et al.’s research study in 1998. The result of the developed control approach indicate a significantly improvement in lighting situation and 1-23% and 50-78% monthly electrical energy savings in the office model, compared to two static strategies when the blinds were left open and closed during the whole year respectively. / Dissertation/Thesis / Doctoral Dissertation Architecture 2015
6

Analysis Methods for Post Occupancy Evaluation of Energy-Use in High Performance Buildings Using Short-Term Monitoring

January 2011 (has links)
abstract: The green building movement has been an effective catalyst in reducing energy demands of buildings and a large number of `green' certified buildings have been in operation for several years. Whether these buildings are actually performing as intended, and if not, identifying specific causes for this discrepancy falls into the general realm of post-occupancy evaluation (POE). POE involves evaluating building performance in terms of energy-use, indoor environmental quality, acoustics and water-use; the first aspect i.e. energy-use is addressed in this thesis. Normally, a full year or more of energy-use and weather data is required to determine the actual post-occupancy energy-use of buildings. In many cases, either measured building performance data is not available or the time and cost implications may not make it feasible to invest in monitoring the building for a whole year. Knowledge about the minimum amount of measured data needed to accurately capture the behavior of the building over the entire year can be immensely beneficial. This research identifies simple modeling techniques to determine best time of the year to begin in-situ monitoring of building energy-use, and the least amount of data required for generating acceptable long-term predictions. Four analysis procedures are studied. The short-term monitoring for long-term prediction (SMLP) approach and dry-bulb temperature analysis (DBTA) approach allow determining the best time and duration of the year for in-situ monitoring to be performed based only on the ambient temperature data of the location. Multivariate change-point (MCP) modeling uses simulated/monitored data to determine best monitoring period of the year. This is also used to validate the SMLP and DBTA approaches. The hybrid inverse modeling method-1 predicts energy-use by combining a short dataset of monitored internal loads with a year of utility-bills, and hybrid inverse method-2 predicts long term building performance using utility-bills only. The results obtained show that often less than three to four months of monitored data is adequate for estimating the annual building energy use, provided that the monitoring is initiated at the right time, and the seasonal as well as daily variations are adequately captured by the short dataset. The predictive accuracy of the short data-sets is found to be strongly influenced by the closeness of the dataset's mean temperature to the annual average temperature. The analysis methods studied would be very useful for energy professionals involved in POE. / Dissertation/Thesis / M.S. Architecture 2011
7

Design of high performance buildings : Vulnerability of buildings to climate change from an energy perspective

Gobert, Robin January 2022 (has links)
The challenge of climate change is twofold: to mitigate (prevent) the causes of climate change and to prepare (adapt) to the inevitable effects and consequences. Building and construction are key sectors for decarbonisation (mitigation). The increase in intensity, frequency and duration of heat waves threatens indoor comfort and constitutes a health and comfort risk (adaptation).Therefore, regulations are being changed to take into account related emissions and extreme episodes through new indicators. However, up to now, past climate observations are still used in the calculation of these indicators. This raises the question of how to integrate future climate predictions into regulations. This work aims at characterising the vulnerability of buildings to climate change and aimsat taking into account future climate predictions in building design. It establishes a method for constructing standard weather data based on climate projections and for identifying vulnerable building typologies that are at risk. This project stands out for the use of a large number of building and meteorological data. 77 residential buildings from the Centre Scientifique et Technique du Bâtiment (CSTB) database and 78 years (1981-2058) of weather data for 9 climate models (RCP8.5 scenario) are crossed for Dynamic Thermal Simulations (DTS) on COMETh. The study first highlights the relevance of using reference and extreme years, representative of the climate data, to reduce the number of simulations. The reference year makes it possible to observe the average needs over a period. The extreme year estimates the range of values around this mean.The report then raises the issue of cooling systems as one of the major challenges for energy needs. Under the effect of climate change, heating requirements are decreasing and largely compensate the increase of cooling needs. But few buildings in France are already equipped with cooling systems and the creation of a need exceeding a threshold leads to the purchase of new units. This raises a problem of social equity in access to thermal comfort. Moreover, the environmentalimpact of these systems is more related to refrigerants necessary for the manufacturethan to energy consumption.The research finally proposes a method to classify passive or active buildings (in the sense of cooling needs), that are adapted or not adapted to future extreme weather conditions. This involves applying a clustering algorithm (k-means) to group similar buildings together in terms of energy requirements for different climate models. This method already makes it possible to identify the buildings at risk and to prioritise the measures to be taken (energy renovation). This classification also opens up the possibility of extending this work to newer, larger and more diversified samples. Similar encouraging results were obtained from 2470 offices. They could helpidentify technical and architectural characteristics and assist in the design of efficient passive buildings.
8

DEVELOPMENT, DESIGN, AND CONSTRUCTION OF A HUMAN-BUILDING INTERACTIONS LABORATORY

Sourabh Deepak Yadav (12224741) 20 April 2022 (has links)
<div>The evolution of existing building construction is envisioned as modular construction. Instead of on-site construction, buildings can be assembled on-site using prefabricated modular elements. These modular elements could integrate intelligent building technologies to enable autonomous, occupant responsive, scalable, cost-effective, and sustainable features. On-site assembly of modular construction elements would offer better quality control, decrease material waste and resources, with more predictable schedules. These building elements would allow more cost-effective integration of new intelligent sensors, adaptive interfaces, renewable energy and energy recovery technologies, comfort delivery, and resiliency technologies, making high-performance buildings more affordable. To explore and evaluate these modular and intelligent comfort delivery concepts and advanced approaches for interaction with occupants, a new Human-Building Interactions Laboratory (HBIL) has been designed and is under development. The facility has a modular construction layout with thermally active panels, and the interior surface temperature of each panel can be individually controlled using a hydronic system. Such configuration allows us to emulate different climate zones and building type conditions and perform studies such as the effect of different kinds of active building surfaces on thermal comfort, localized comfort delivery, and occupant comfort control. Moreover, each panel is reconfigurable to investigate different interior surface treatments for thermal, visual, and acoustic comfort conditions. <br></div><div>In this MS thesis work, the overall design approach of the facility is presented. Development, experimental investigation of thermal performance, and aligned design modifications of a prototype thermo-active wall panel are explained in detail. Detailed development of a 1-D transient numerical model for the prototype wall panel and its tuning and validation are also presented. Furthermore, the design and installation plan of the hydronic system for the HBIL facility are also presented with an initial commissioning plan.</div>

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