Architecture Commons^™

Ann Based Load Identification And Forecasting System For The Built Environment, Hosen Hasna

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

"Phantom Loads" cause energy waste in homes and the built environment as a whole. Consumers spend more than $3 billion a year on "Phantom Load" in the United States alone. The goal of this work is to conserve energy by increasing consumer awareness on their energy usage and appropriate tools which in turn will be reducing and /or eliminating phantom loads and mismanagement of the load in the built environment. A further goal is to improve upon existing power distribution systems in the built environment with limited hardware additions to increase energy conservation. This work investigates remote identification of load …

Technologies Enabling Sustainability In The Built Environment, Mahmoud Alahmad, Muhammad Zulfiqar, Hosen Hasna Hh, Timothy Wisnieski, Nasser Aljuhaishi, Hamid Sharif

Durham School of Architectural Engineering and Construction: Faculty Publications

Energy conservation is among society’s greatest challenges, and the built environment has a concentrated impact on our natural environment, economy, and health. Fundamental understandings of how energy is consumed, monitored, and controlled are key prerequisites for an energy conservation process. This paper evaluates the effectiveness of real-time energy monitors (RTM) to influence behavior change in residential consumers. A methodology for remote identification of load types along the electrical circuitry where they (load) are being consumed is also presented. The load type and status (on, off, standby) are determined both remotely and in a non-intrusive manner using Non-Intrusive Load Monitoring Methods. …

Implementation Of Integrated Commissioning, Retrofits, And Control Optimization Process In A Small Commercial Building, Xiangnan Shi

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

A large amount of the primary energy consumed in the US is derived from the built environment followed by energy consumed in the transportation and industrial sectors. Consequently, improving the energy efficiency of buildings is an important part of ensuring a more sustainable world for future generations. Of the various techniques employed to improve the energy efficiency of buildings, commissioning and retrofits continue to be the most widely applied solutions. Control optimization, mainly imbedded with continuous commissioning so far, is not applied as widely. Even though there are currently a few applications that integrate all three techniques, no comparison has …

Optimized Control Strategies For A Typical Water Loop Heat Pump System, Xu Lian

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

Water Loop Heat Pump (WLHP) System has been widely utilized in the Heating, Ventilating and Air Conditioning (HVAC) industry for several decades. There is no doubt about the energy saving potential of this type of system from the design and construction perspective. However, there are still many unsolved problems, such as high loop pump energy consumption, low heat pump efficiency and high electricity cost due to improper operation, although the system design intension was to save energy. Thus, how to control the WSHP to realize its energy-efficient value is an innovative but practical topic on which this thesis will focus. …

A Virtual Supply Airflow Rate Meter In Rooftop Air Conditioning Units, Daihong Yu

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

Virtual sensing technology aims to estimate difficult to measure, expensive, or new quantities by using multifarious mathematical models along with non-invasive and low-cost measurements. Such embedded intelligence is a key to improving the performance of building systems in terms of functionality, safety, energy efficiency, environmental impacts, and costs. Considering the progress that has been achieved over many various fields (e.g., process controls, automobiles, avionics, autonomous robots, telemedicine) within the last two decades, numerous intelligent features have been incorporated and enabled that would otherwise not be possible or economical.

To identify the potential opportunities and research/development needs of virtual sensing technology …

Investigations Of The Relationships Between Unoccupied Classroom Acoustical Conditions And Elementary Student Achievement, Lauren M. Ronsse

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

Current building standards recommend specific unoccupied background noise levels and reverberation times for classroom spaces. While clear communication in elementary school classrooms may be critical for successful learning environments, the existing research does not show a consistent connection between the classroom acoustics parameters specified in building standards and student achievement. This research seeks to determine what acoustical conditions should be attained in elementary school classrooms to optimize student achievement.

In this dissertation, acoustical studies in two midwestern United States public school systems are described. Unoccupied background noise level (BNL) and reverberation time (RT) measurements were gathered in a range of …

Adaptive Photovoltaic Configurations For Decreasing The Electrical Mismatching Losses, Mohamed Amer Chaaban

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

Electrical mismatching losses in photovoltaic systems are of great interest to system designers. In this thesis, an adaptive photovoltaic (PV) system is proposed based on novel flexible switch matrixes that form different possible topologies. This system maximizes the generated power in real-time for utility interactive systems in a modified inverter configuration. The proposed system uses fewer components and achieves maximum efficiency during shading and module mismatches by reconfiguring the PV modules based on real-time solar insolation, current operational conditions, and maximum efficiency criterion. Simulation tools are used to demonstrate that the proposed topologies provide improvement in efficiency over existing traditional …

Real-Time Power Monitoring, Home Automation And Sustainability, Wisam Nader

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

As the supply and demand of electrical energy is challenged within the context of environmental awareness and national security, the need to evaluate and advance each side is growing in importance. The electrical distribution system plays a critical role in the built environment as it is an enabling product, an intangible necessity used to power our systems. In order to manage our energy and prevent the consequences caused by energy wastage we need to develop tools for the built environment to become elastic with its consumption to respond to the national smart grid. To advance the research in this field, …

Impacts Of Static Pressure Reset On Vav System Air Leakage, Fan Power And Thermal Energy- Part 1: Theoretical Model And Simulation, Mingsheng Liu, Jingjuan Feng, Zhan Wang, Lixia Wu, Keke Zheng, Xiufeng Pang

Durham School of Architectural Engineering and Construction: Faculty Publications

As for a variable air volume (VAV) System, the air duct static pressure is a typical control variable maintained by modulating supply fan speed. The static pressure equals to the summation of the duct pressure loss downstream of the sensor to the terminal box and box inlet static pressure. Typically, the air duct static pressure is set as a constant set point based on the system design information and sensor location. However, under partial load conditions, the terminal dampers have to be closed more since the required airflow which directly leads to much less pressure loss. This the static pressure …

Application Of Wireless Sensor Network (Wsn) Technologies In Optimal Static Pressure Reset In Variable Air Volume (Vav) System, Keke Zheng, Haorong Li, Huojun Yang

Durham School of Architectural Engineering and Construction: Faculty Publications

Optimization of the static pressure reset is always critical in the pursuit of maximum savings of fan power and thermal energy consumption in a VAV system. This paper theoretically investigated three static pressure reset methods, i.e. VAV terminal unit damper position based, outside air temperature based and air flow based, and proposed an optimal static pressure reset method. Subsequently, hourly simulations of a building in Omaha, Nebraska, USA, was implemented and validated that the VAV system with the optimal reset method could consume the least fan energy without sacrificing thermal comfort. Furthermore, in consideration of typical advantages or wireless technologies …

Economizer Control Using Mixed Air Enthalpy, Jingjuan Feng, Mingsheng Liu, Xiufeng Pang

Durham School of Architectural Engineering and Construction: Faculty Publications

Enthalpy economizer can theoretically save more energy than temperature based economizer. However, the requirement of outdoor air humidity measurement in the traditional enthalpy economizer control made it impossible. A novel control sequence using mixed air enthalpy is developed in the paper. Both theoretical and experimental investigation shows that humidity measurement in mixed air duct is very reliable, and the proposed method can achieve true enthalpy economizer saving. A case implementation shows 15.7% more energy saving than temperature based economizer in Omaha, NE.

A Virtual Supply Airflow Rate Meter In Rooftop Air Conditioning Units, Daihong Yu

Durham School of Architectural Engineering and Construction: Dissertations, Thesis, and Student Research

Virtual sensing technology aims to estimate difficult to measure, expensive, or new quantities by using multifarious mathematical models along with non-invasive and low-cost measurements. Such embedded intelligence is a key to improving the performance of building systems in terms of functionality, safety, energy efficiency, environmental impacts, and costs. Considering the progress that has been achieved over many various fields (e.g., process controls, automobiles, avionics, autonomous robots, telemedicine) within the last two decades, numerous intelligent features have been incorporated and enabled that would otherwise not be possible or economical.

To identify the potential opportunities and research/development needs of virtual sensing technology …

Lv-11-C031: Measured Levels Of Hospital Noise Before, During, And After Renovation Of A Hospital Wing, And A Survey Of Resulting Patient Perception, Cassandra H. Wiese, Lily M. Wang

Durham School of Architectural Engineering and Construction: Faculty Publications

Acoustic conditions in hospitals can negatively influence a patient’s physical and psychological health. This paperreports on noise levels measured before, during, and after renovation of a hospital wing in an Omaha, Nebraska, facility thatregularly receives unsatisfactory noise scores on patient satisfaction surveys. Sound pressure levels were logged every 10seconds over four-day periods in three different locations: at the nurses' station, in the hallway, and in a nearby patient’sroom. The resulting data have been analyzed in terms of A-weighted equivalent sound levels (LAeq) as well as variousexceedance levels (Ln). Results indicate that sound levels did not change much due to the …

The “Bim’S 4d+” Dimension: Real Time Energy Monitoring, Mahmoud Alahmad, Wisam Nader, Adam Brumbaugh, Yong Cho, Song Ci, Hamid Sharif, Jonathan Shi, Jill Neal

Durham School of Architectural Engineering and Construction: Faculty Publications

With the current trend towards Building Information Model (BIM), facility managers have a new tool for raising efficiency. This paper discusses the integration of the BIM software with a real-time monitoring (RTM) system, as a 4D+ dimension in BIM, to track the electrical usage at every location in a building. This ability could be invaluable in identifying what unnecessary loads are connected to a device and could be disconnected. This would result in elimination of needless loads and phantom loads during non-business hours, causing significant reduction in energy consumption. A prototype of the RTM was built and the results are …

An Adaptive Photovoltaic-Inverter Topology, Mahmoud Alahmad, Mohamed Amer Chaaban, Siu Kit Lau

Durham School of Architectural Engineering and Construction: Faculty Publications

A new inverter topology for Adaptive photovoltaic (PV) system is proposed. An improvement in the power generation of the system during different operating conditions is achieved. The proposed configuration provides flexible connection between the PV modules and the inverters to meet current conditions of PV array. Preliminary simulation results are provided for an adaptive PV array. Efficiency comparison between traditional PV system configurations is discussed. Potential improvement using the proposed adaptive configuration is sited.

Non-Intrusive Electrical Load Monitoring And Profiling Methods For Applications In Energy Management Systems, Mahmoud Alahmad, Hosen Hasna Hh, Evans Sordiashie

Durham School of Architectural Engineering and Construction: Faculty Publications

"Phantom Loads" cause energy waste in homes and the built environment as a whole. Consumers spend more than $3 billion a year on "Phantom Load" in the United States alone. The goal of this paper is to conserve energy by increasing consumer awareness on their energy usage and reducing and /or eliminating phantom loads in the built environment. A further goal is to improve upon existing power distribution systems in the built environment with limited hardware additions to increase energy conservation. This paper investigates remote identification of load types and the locations along the electrical circuitry where they (load) are …

A Novel Photovoltaic/Battery Structure For Solar Electrical Vehicles [Pvbs For Sev], Mahmoud Alahmad, Mohamed Amer Chaaban, Lana Chaar

Durham School of Architectural Engineering and Construction: Faculty Publications

In this paper, we propose a new flexible Photovoltaic/Battery charging Structure for Solar Electrical Vehicles (PVBS), where the interconnection of the system is dynamically changing based on current shading conditions across PV modules to provide intelligent system, as well as to provide flexibility, performance, and efficiency enhancement for the SEV. PVBS is expected to 1) provide a battery charging efficiency improvement over existing employed topologies; 2) provide new means to match the computing load with the PV system performance metrics shading and mismatches; 3) and provide elastic reconfigurable system expected to spur research advancements and innovations to make future SEV …

Optimization Of Energy Storage Systems In Hev's, Mahmoud Alahmad, Mohamed Amer Chaaban

Durham School of Architectural Engineering and Construction: Faculty Publications

This paper introduces a novel battery model inspired by molecular structures mainly for applications in HEV’s. This novel 3-D adaptive battery topology shows potential for improvement in input and output performance as well as the charging/ discharging efficiency of batteries. The proposed topology provides flexible connections between battery cells to achieve different configurations of battery. A new switching matrix has been developed to achieve the required configurations. Preliminary simulations provide promising results for an adaptive 3-D battery configuration. Comparison between traditional battery configurations and the adaptive 3-D configuration is considered. A significant improvement in power curves is achieved by the …

Green And Sustainable Technologies For The Built Enviornment, Mahmoud Alahmad, Muhammad Zulfiqar, Hosen Hasna Hh, Hamid Sharif, Evans Sordiashie, Nasser Aljuhaishi

Durham School of Architectural Engineering and Construction: Faculty Publications

Energy conservation is among society’s greatest challenges, and the built environment has a concentrated impact on our natural environment, economy, and health. Fundamental understandings of how energy is consumed, monitored, and controlled are key prerequisites for an energy conservation process. This paper evaluates the effectiveness of real-time energy monitors (RTM) to influence behavior change in residential consumers. A methodology for remote identification of load types and the locations along the electrical circuitry where they (load) are being consumed is also presented. The load type and status (on, off, standby) are determined both remotely and in a non-intrusive manner using Non-Intrusive …

Combinatorics & Power Consumption, Mahmoud Alahmad, Wisam Nader

Durham School of Architectural Engineering and Construction: Faculty Publications

in this paper the power consumption possible combinations for a number of loads and a single power source are discussed. The proposed mathematical model depends basically on combinatorics to estimate how many ways are possible to operate different loads powered by a single power source. This paper takes into consideration the different conditions and limitations to operate n number of loads limited by their minimum and maximum values of power consumption. Four different cases of operations are discussed and modeled. A flowchart and a step-by-step method to do the calculations for a general case is also illustrated at the end …

Addressable And Energy Management System For The Built Environment (I), Mahmoud Alahmad, Hosen Hasna Hh, Evans Sordiashie

Durham School of Architectural Engineering and Construction: Faculty Publications

The increasing awareness for a cleaner earth has created more interests in the electric vehicle (EV) technology. Electric vehicles (EVs) will not only cause a reduction in our current greenhouse gas emissions, but also stop or reverse the trend at which our natural resources are being depleted. However, the introduction of the EVs into our societies will still require energy usage in the form of electricity. Integration of charging infrastructures will eventually be required in the built environment for these vehicles. This will add to the current energy consumption in the built environment which will mean more emission of CO2, …

Industry-Experienced Graduate Student Program: Innovative Collaboration In Architectural Engineering At The University Of Nebraska–Lincoln, Clarence E. Waters, Steve Alvine, Michelle L. Eble-Hankins

Durham School of Architectural Engineering and Construction: Faculty Publications

In 2001, the Architectural Engineering Department at the University of Nebraska–Lincoln, along with industry partners, established an industry-experienced graduate student program. The program was developed to bring experienced design professionals to collaborate with the industry while pursuing a Ph.D. in architectural engineering. This program is designed to be mutually beneficial to industry partners, -graduate students, the University of Nebraska–Lincoln Architectural Engineering Department, and the building industry at large. The first doctoral candidate in the program graduated, and significant collaborative work was completed for the industry partner. All parties to this initial offering are pleased with the outcome and believe the …