Theses and Dissertations from UMD
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New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a give thesis/dissertation in DRUM
More information is available at Theses and Dissertations at University of Maryland Libraries.
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Item DETERMINING MEASUREMENT REQUIREMENTS FOR WHOLE BUILDING ENERGY MODEL CALIBRATION(2020) Dahlhausen, Matthew Galen; Srebric, Jelena; Mechanical Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Energy retrofits of existing buildings reduce grid requirements for new generation and reduce greenhouse gas emissions. However, it is difficult to estimate energy savings, both at the individual building and entire building stock level, because building energy models are poorly calibrated to actual building performance. This uncertainty has made it difficult to prioritize research and development and incentive programs for building technologies at the utility, state, and federal level. This research seeks to make it easier to generate building energy models for existing buildings, and to calibrate buildings at the stock level, to create accurate commercial building load forecasts. Once calibrated, these building models can be used as seeds to other building energy model calibration approaches and to help utility, state, and federal actors to identify promising energy saving technologies in commercial buildings. This research details the economics of a building energy retrofit at a singular building; contributes significantly to the development of ComStock, a model of the commercial building stock in the U.S.; identifies important parameters for calibrating ComStock; and calibrates ComStock for an example utility region of Fort Collins, CO against individual commercial building interval data. A study of retrofit costs finds that measure cost and model uncertainty are the most significant sources of variation in retrofit financial performance, followed financing cost. A wide range of greenhouse gas pricing scenarios show they have little impact on the financial performance of whole building retrofits. A sensitivity analysis of ComStock model inputs across an exhaustive range of models identifies 19 parameters that explain 80 of energy use and 25 parameters that explain 90% of energy use. Building floor area alone explains 41% of energy use. Finally, a comparison of ComStock to Fort Collins, CO interval meter data shows a 6.92% normalized mean bias error and a 16.55% coefficient of variation of root mean square error based on normalized annual energy per floor area. Improvements in meter classification and ComStock model variability will further improve model fit and provide an accurate means of modeling the commercial building stock.Item Transition pathways of China and implications for climate change mitigation: evolution of the buildings sector(2017) Yu, Sha; Hultman, Nathan E; Public Policy; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)China, as the world’s largest energy consumer and greenhouse gas emitter, also has the largest construction market. Energy use in Chinese buildings (including traditional biomass) constitutes 28% of China’s total final energy consumption and 16% of global building final energy consumption in 2012. Driven by economic growth, urbanization, and lifestyle changes, energy consumption in Chinese buildings is expected to continue to grow. Buildings will therefore be an important element of efforts by the Chinese government to plan infrastructure, constrain energy growth, or meet a range of related sustainability goals. This dissertation examines the evolution of the Chinese buildings sector and focuses on three issues. First, in order to make robust projections, we investigate the historical growth of the buildings sector in China, Japan, and the United States. The growth paths of Japan and the United States provide useful historical analogs for China’s future growth. We find that the change in energy use intensity was driven by short-term events, such as introduction of new policies, and showed greater variability compared to other drivers, whereas growth in per capita floorspace and household characteristics showed consistent long-term trends and was less responsive to short-term events. Second, we examine the growth in floorspace by province and building type. We use Gompertz model to estimate future floorspace growth, as it captures dynamics between floorspace and income and the saturated demand. This study shows variation across provinces in floorspace growth and a wider range of floorspace at the aggregate level than literature. It also has strong policy implications, as housing policies, in addition to building energy policies, are critical to curbing the growth in China’s building energy use. Third, using the Global Change Assessment Model-China (GCAM-China), we assess China’s future building energy demand under different transition pathways while accounting for provincial heterogeneity. We find that distinct development paths can lead to different levels of building energy consumption in China (25-42 EJ in 2050), and most growth would happen in the next two decades. Strong, provincial-specific near-term policy actions are needed in order to avoid locking in the inefficient infrastructure.