Performance Modeling of an Air-Based Photovoltaic/Thermal (PV/T) Collector

This paper studies a collector design that utilizes unglazed photovoltaic/thermal (PV/T) collectors preheating air for glazed air heating modules. The performance modeling of these collectors is examined both individually and in series. For each collector type, a dynamic, finite difference, first-law model has been created using literature correlations for friction. The models were compared to performance data, calibrating the models by scaling of friction terms for best fit. The calibrated models generally agree well with the experimental data; even during sudden changes to ambient conditions. The root mean square error between the unglazed PV/T model and experiment results for the useful thermal energy gain and the outlet air temperature are 7.12 W/m2 and 1.07°C, respectively. The annual source energy performance of the building-integrated PV/T (BIPV/T) array is then simulated for residential applications in seven climate zones of the United States of America. The performance of the BIPV/T array is characterized by the amount of net electrical energy and useful thermal energy produced. The useful thermal energy is defined as the amount of energy offset by the BIPV/T system for water heating and space conditioning. A BIPV/T system composed 87.5% of PV modules, and 12.5% of glazed air heating modules, offsets the same amount of source energy as a roof-mounted PV system of the same area. This array composition increases the thermal energy gain by 47% over a BIPV/T array composed solely of PV modules.

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Energy performance modeling of a stand-alone PV system using real meteorological data

2017 XXVI International Scientific Conference Electronics (ET) ◽

10.1109/et.2017.8124330 ◽

2017 ◽

Author(s):

Svetlozar Kirilov Zahariev ◽

Kaloyan Svetlozarov Kirilov ◽

Mariela Ivanova Alexandrova

Keyword(s):

Performance Modeling ◽

Meteorological Data ◽

Energy Performance ◽

Pv System

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Uncertainty Estimates of Photovoltaic Module Performance Measurements

Solar Energy ◽

10.1115/isec2003-44224 ◽

2003 ◽

Cited By ~ 1

Author(s):

Gobind H. Atmaram

Keyword(s):

The United States ◽

Laboratory Accreditation ◽

Photovoltaic Module ◽

Certification Program ◽

Performance Measurements ◽

Pv System ◽

Testing Laboratory ◽

Pv Module ◽

Uncertainty Estimates ◽

Pv Modules

Commercially available photovoltaic (PV) modules and systems often fall short of meeting the performance ratings specified by the module manufacturers or system designers [1]. This has resulted in reduced performance and low system availability, some system failures, and generally, a lack of confidence by systems users. Hence, a need for an independent accredited laboratory to conduct the testing and certification of PV modules and systems has been indicated by the PV industry, electric utilities, and other system users and owners. To meet this industry and user need, the Florida Solar Energy Center (FSEC) has started a PV testing and certification program. The FSEC PV testing laboratory and certification program have been accredited by the American Association for Laboratory Accreditation (A2LA) and approved by the PowerMark Corporation (PMC, www.powermark.org ), which is the certification body of the PV industry in the United States. The FSEC program currently covers three areas: (i) PV module power rating certification, (ii) Stand-Alone PV system performance evaluation and certification, and (iii) Grid-Connected PV system design review and approval. The PV module power rating certification is central to these three areas of the FSEC program, as illustrated in Figure 1. The details of the FSEC PV testing laboratory accreditation and certification program are described in a previous paper [2].

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Experimental Study on the Performance of a Phase Change Slurry-Based Heat Pipe Solar Photovoltaic/Thermal Cogeneration System

International Journal of Photoenergy ◽

10.1155/2019/9579357 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Hongbing Chen ◽

Yutong Gong ◽

Ping Wei ◽

Pingjun Nie ◽

Yaxuan Xiong ◽

...

Keyword(s):

Phase Change ◽

Heat Pipe ◽

Thermal Energy ◽

Unit Area ◽

Energy Performance ◽

Hot Water ◽

Electrical Performance ◽

Working Fluid ◽

Solar Pv ◽

T System

By employing phase change slurry (PCS) as working fluid for the heat pipe solar PV/T system, the study is designed to investigate the electrical and thermal energy performance of the system. Meanwhile, through examining the performance difference between water-based and PCS-based heat pipe solar PV/T systems, 30% alkyl hydrocarbon PCS is proved to be a suitable working fluid for optimized energy performance based on the combined consideration of the thermophysical and rheological properties. Both static and dynamic stability tests show that 30% alkyl hydrocarbon PCS has a good stability for low-temperature thermal energy storage. A testing rig is constructed consisting of two identical heat pipe solar PV/T cogeneration systems A and B, in which water and 30% alkyl hydrocarbon PCS are, respectively, employed as working fluids; the energy performance of those two PV/T systems are investigated and compared with each other under the same testing condition. The results indicate that the application of PCS to the heat pipe PV/T system leads to a significant improvement in thermal performance and a modest growth in electrical performance. The daily heat gains and overall average efficiency of system B are 4.2 MJ/m2 (per unit area of PV/T panel) and 59.3%, respectively, 27.3% and 9.3% higher than those of system A. Per unit area of the heat pipe PV/T panel could produce 55.2 L domestic hot water of about 45°C on a sunny day.

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Energy Performance Investigation of Bi-Directional Convergence Energy Prosumers for an Energy Sharing Community

Energies ◽

10.3390/en14175544 ◽

2021 ◽

Vol 14 (17) ◽

pp. 5544

Author(s):

Min-Hwi Kim ◽

Dong-Won Lee ◽

Deuk-Won Kim ◽

Young-Sub An ◽

Jae-Ho Yun

Keyword(s):

Heat Pump ◽

Thermal Energy ◽

Energy Performance ◽

Economic Benefits ◽

Pv System ◽

Pump System ◽

Heat Pump System ◽

Pv Systems ◽

Energy Prosumers ◽

Energy Sharing

Due to the wide-spread use of photovoltaic (PV) systems, interest regarding economic benefit and energy-sharing from surplus electricity has been raised. In this study, decentralized thermal and electric convergence energy prosumers for an energy-sharing community are proposed. For the convergence energy system, a simultaneous heating and cooling heat pump (SHCHP) system integrated with a thermal network is proposed, and the energy performance and operating energy savings of the proposed system were investigated. A smart village located in the Busan Eco Delta Smart City was selected as a case study for the simulation analysis. Experimental data of the heat pump system were used to analyze the SHCHP. The analysis results showed that the proposed system could provide over 53% and 86% of the load cover and supply cover factors, respectively. The proposed system can earn economic benefits, such as energy trading from the surplus electricity of PV systems and thermal energy produced by an SHCHP, more than 30.5 times those of conventional air-source heat pump systems. These benefits mainly originate that a conventional system can trade the surplus electricity from a PV system but the proposed system can trade produced thermal energy from SHCHPs and the surplus electricity from PV systems.

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An Experimental Investigation on Energy Performance of The Hybrid Photovoltaic Thermal System

E3S Web of Conferences ◽

10.1051/e3sconf/202019708003 ◽

2020 ◽

Vol 197 ◽

pp. 08003

Author(s):

Shahrokh Barati ◽

Livio de Santoli ◽

Gianluigi Lo Basso ◽

Antonio Galizia ◽

Giulia Spiridigliozzi

Keyword(s):

Hybrid System ◽

Thermal Energy ◽

Fossil Fuels ◽

Ghg Emissions ◽

Energy System ◽

Energy Performance ◽

Integrated System ◽

Hybrid Energy ◽

Photovoltaic Thermal System ◽

T System

Climate change is a worldwide recognized problem, and its mitigation identified as one of the most significant challenges. The way to achieve this purpose is to reduce greenhouse gases (GHG) emissions through the energy system using renewables. The change from an energy system based on fossil fuels to renewable sources-based one is necessary on which the world community agrees. A photovoltaic thermal (PV/T) panel is a system that can produce both electricity and thermal energy simultaneously in one integrated system. This paper deals with hybrid energy systems, specifically a hybrid system to produce power and thermal energy from solar sources consisting of photovoltaic thermal modules. The hybrid system consists of 7 hybrid photovoltaic panels installed on the roof of the laboratory. This paper presents a study for experimental data obtained from a measurement campaign of the thermal and electrical behavior of a PV/T system in single and series models.

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Occupant behaviour and thermal comfort in buildings: Monitoring the end user

E3S Web of Conferences ◽

10.1051/e3sconf/201911104056 ◽

2019 ◽

Vol 111 ◽

pp. 04056

Author(s):

Loes Visser ◽

Boris Kingma ◽

Eric Willems ◽

Wendy Broers ◽

Marcel Loomans ◽

...

Keyword(s):

Thermal Comfort ◽

Energy Performance ◽

The Body ◽

Activity Level ◽

Biophysical Model ◽

Zone Model ◽

Occupant Behaviour ◽

Ambient Conditions ◽

Skin Temperatures ◽

Thermoregulatory Behaviour

Studies indicate that the energy performance gap between real and calculated energy use can be explained for 80% by occupant behaviour. This human factor may be composed of routine and thermoregulatory behaviour. When occupants do not feel comfortable due to high or low operative temperatures and resulting high or low skin temperatures, they are likely to exhibit thermoregulatory behaviour. The aim of this study is to monitor and understand this thermoregulatory behaviour of the occupant. This is a detailed study of two females living in a rowhouse in the city of Heerlen (Netherlands). During a monitoring period of three weeks over a time span of three months the following parameters were monitored: activity level, clothing, micro climate, skin temperatures and thermal comfort and sensation. Their micro climate was measured at five positions on the body to assess exposed near body conditions and skin temperature. Every two hours they filled in a questionnaire regarding their thermal comfort and sensation level (7-point scale), clothing, activities and thermoregulatory behaviour. The most comfortable (optimal) temperature was calculated for each person by adopting a biophysical model, a thermoneutral zone model. This study shows unique indivual comfort patterns in relation to ambient conditions. An example is given how this information can be used to calculate the buildings energy comsumption.

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A Study of Optimal Specifications for Light Shelves with Photovoltaic Modules to Improve Indoor Comfort and Save Building Energy

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052574 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2574

Author(s):

Heangwoo Lee ◽

Xiaolong Zhao ◽

Janghoo Seo

Keyword(s):

Energy Savings ◽

Building Energy ◽

Energy Performance ◽

Building Energy Efficiency ◽

Efficiency Change ◽

Photovoltaic Modules ◽

Heating And Cooling ◽

Pv Module ◽

Pv Modules ◽

Indoor Comfort

Recent studies on light shelves found that building energy efficiency could be maximized by applying photovoltaic (PV) modules to light shelf reflectors. Although PV modules generate a substantial amount of heat and change the consumption of indoor heating and cooling energy, performance evaluations carried out thus far have not considered these factors. This study validated the effectiveness of PV module light shelves and determined optimal specifications while considering heating and cooling energy savings. A full-scale testbed was built to evaluate performance according to light shelf variables. The uniformity ratio was found to improve according to the light shelf angle value and decreased as the PV module installation area increased. It was determined that PV modules should be considered in the design of light shelves as their daylighting and concentration efficiency change according to their angles. PV modules installed on light shelves were also found to change the indoor cooling and heating environment; the degree of such change increased as the area of the PV module increased. Lastly, light shelf specifications for reducing building energy, including heating and cooling energy, were not found to apply to PV modules since PV modules on light shelf reflectors increase building energy consumption.

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Performance and style in the work of Olgyay and Olgyay

Architectural Research Quarterly ◽

10.1017/s1359135514000475 ◽

2014 ◽

Vol 18 (2) ◽

pp. 167-176 ◽

Cited By ~ 3

Author(s):

David Leatherbarrow ◽

Richard Wesley

Keyword(s):

Graphical Representation ◽

Building Design ◽

The United States ◽

Energy Performance ◽

Control Device ◽

Simulation Software ◽

Open Architecture ◽

Form Generation ◽

The Difference ◽

Building Energy Analysis

The sun control device has to be on the outside of the building, an element of the facade, an element of architecture. And because this device is so important a part of our open architecture, it may develop into as characteristic a form as the Doric column.Victor Olgyay (1910–1970), a Hungarian architect who came to the United States in 1947 with his twin brother and collaborator, Aladár (1910–1963), is best known today as the author of Design with Climate: Bioclimatic Approach to Architectural Regionalism (1963), an important book often referenced in the environmental building design field [1]. As leaders in research in bioclimatic architecture from the early 1950s to the late 1960s, the Olgyay brothers could be considered the ‘fathers’ of contemporary environmental building design. Their research and publications laid the foundation for much of the building simulation software in use today. Other than the difference between working on graph paper and using computer-generated graphics, there is little difference between Autodesk's Ecotect Analysis (simulation and building energy analysis software) and the Olgyays' techniques for the analysis of environmental factors and graphical representation of climate. The manner in which the Olgyays established connections between building design and the science of climate laid the foundation for the development of environmental simulation, one of contemporary architecture's leading methods of form generation. Victor Olgyay's teaching, however, represents another kind of thinking, a broader concern for architecture, beyond energy performance. ‘The primary task of architecture,’ Olgyay announced to his students, ‘is to act in man's favour; to interpose itself between man and his natural surroundings in order to remove the environmental load from his shoulders.

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