scholarly journals Energy and Luminous Performance Investigation of an OPV/ETFE Glazing Element for Building Integration

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1870
Author(s):  
Álex Moreno ◽  
Daniel Chemisana ◽  
Rodolphe Vaillon ◽  
Alberto Riverola ◽  
Alejandro Solans
Keyword(s):  
Energy Performance ◽  
Climatic Conditions ◽  
Organic Photovoltaic ◽  
Net Energy ◽  
Coverage Area ◽  
Wide Range ◽  
Balancing Energy ◽  
The One ◽  
Electrical Generation ◽  
Ethylene Tetrafluoroethylene

The combination of architectural membranes such as ethylene tetrafluoroethylene (ETFE) foils and organic photovoltaic (OPV) cells offers a wide range of possibilities for building integration applications. This is due to their flexibility, free-shape, variable color and semitransparency, light weight, cost-effectivity, and low environmental impact. In addition, electrical generation is provided. Four configurations of ETFE foils designed to be integrated onto a south façade glazing element were studied for two representative European locations with different climatic conditions: Barcelona and Paris. These configurations comprise a reference one based on a double ETFE foil with a 10 mm air gap in between, and the other three incorporate on the inner ETFE foil either OPV cells covering 50% or 100% of its surface or a shading pattern printed on it covering 50% of its surface. Results show that, in terms of energy, the configuration with higher OPV coverage area is the one achieving the lowest net energy consumption in both locations. However, when looking at the illumination comfort this option results in insufficient illumination levels. Therefore, a tradeoff strategy balancing energy performance and illumination comfort conditions is necessary. Based on that, the best solution found for both cities is the configuration integrating OPV cells covering 50% of the glazing area and for a window to wall ratio of 0.45.

scholarly journals Exergoeconomic and Enviroeconomic Analysis of Photovoltaic Modules of Different Solar Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Ankita Gaur ◽  
G. N. Tiwari
Keyword(s):  
Solar Cells ◽  
Cost Reduction ◽  
Loss Rate ◽  
Climatic Conditions ◽  
Environmental Cost ◽  
New Delhi ◽  
Net Energy ◽  
Pv Module ◽  
Pv Modules ◽  
The One

The exergoeconomic and enviroeconomic analysis of semitransparent and opaque photovoltaic (PV) modules based on different kinds of solar cells are presented. Annual electricity and net present values have also been computed for the composite climatic conditions of New Delhi, India. Irrespective of the solar cell type, the semitransparent PV modules have shown higher net energy loss rate (Len) and net exergy loss rate (Lex) compared to the opaque ones. Among all types of solar modules, the one based on c-Si, exhibited the minimum Len and Lex. Compared to the opaque ones, the semitransparent PV modules have shown higher CO2 reduction giving higher environmental cost reduction per annum and the highest environmental cost reduction per annum was found for a-Si PV module.

scholarly journals Parametric Study of Air Infiltration in Residential Buildings—The Effect of Local Conditions on Energy Demand

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 127
Author(s):  
Artur Miszczuk ◽  
Dariusz Heim
Keyword(s):  
Energy Demand ◽  
Computational Models ◽  
Residential Buildings ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Physical Parameters ◽  
Local Conditions ◽  
Change Rate ◽  
Air Change Rate ◽  
Wide Range

Airtightness is nowadays one of the physical parameters which determine overall building energy performance. In a wide range of states, the upper limit for air change rate at a Pa (na), air permeability rate at a Pa (qa), or specific leakage rate at a Pa (wa) is determined by the formal regulations. It should be highlighted that airtightness requirements are mainly the same around the world, disregarding any site and climatic conditions. The main goal of the presented work was to reveal the effect of individual location and surrounding infiltration rate and heat demand. The analyses were done using numerical techniques and computational models of the three buildings developed and calibrated based on the blower door test results. The compared buildings characterize by a similar geometry but differ in the air change rate at 50 Pa (n50). Analyses done for different locations and levels of sheltering by surrounding elements allow the determination of the real effect of local conditions. The obtained differences in energy demand between two locations from the same climatic zone were from 70% to 90%, depending on the airtightness of the buildings. Considering different sheltered conditions, the differences for the same location can be even 200%. The obtained results allowed for the formulation of the general conclusion that building location and level of exposure could be considered in future airtightness regulations.

scholarly journals Experimental Assessment of a Multi-Variable Control Strategy of a Micro-Cogeneration Solar-ORC Plant for Domestic Application

2021 ◽  
Vol 312 ◽  
pp. 08006
Author(s):  
Diego Vittorini ◽  
Fabio Fatigati ◽  
Davide Di Battista ◽  
Marco Di Bartolomeo ◽  
Roberto Carapellucci
Keyword(s):  
High Temperature ◽  
Flat Plate ◽  
Thermal Power ◽  
Energy Performance ◽  
Hot Water ◽  
Small Scale ◽  
Domestic Hot Water ◽  
Wide Range ◽  
Electrical Generation ◽  
Operating Points

Suitability to off-design operation, applicability to combined thermal and electrical generation in a wide range of low temperatures and pressures and compliance with safety and environmental limitations qualify small-scale Organic Rankine Cycle plants as a viable option for combined heat and power generation in the residential sector. As the plants scale down, the electric and thermal output maximization has to account for issues, spanning from high pump power absorption, compared to the electric output of the plant, to intrinsically low plant permeability induced by the expander, to the intermittent availability of thermal power, affected by the heat demand for domestic hot water (DHW) production. The present paper accounts for a flat-plate solar thermal collector array, bottomed by an ORC unit featuring a sliding vane expander and pump and flat-plate heat exchangers. A high-temperature buffer vessel stores artificially heated water – electric heaters, simulating the solar collector - and feeds either the hot water line for domestic use or the ORC evaporator, depending on the instantaneous demand (i.e., domestic hot water or electric power), the temperature conditions inside the tank and the stored mass availability. A low-temperature receiver acts like the heat sink of the ORC unit and harvests the residual thermal power, downstream the expander: a dedicated control, modelled to properly modulate the mass addition/subtraction to this storage unit allows to restore the operating points of the cycle and to limit the incidence of off-design operation, via real-time adjustment of the cycle operating parameters. Indeed, the possibility of continuous ORC generation depends on (i) the nature of the demand and (ii) the amount of hot water withdrawn from the high-temperature buffer vessel. The time-to-temperature for the mass stored inside the buffer affects the amount of ORC unit activations and eventually the maximum attainable generation of electric energy. The plant energy performance is experimentally assessed, and various characteristic operating points are mapped, based on test runs carried out on a real-scale ORC pilot unit.

scholarly journals The Effects of Exterior Thermal Mass (eTM) on Energy Consumption in Residential Buildings

2019 ◽  
Vol 3 (1) ◽  
pp. 14
Author(s):  
Amir Ghoreishi
Keyword(s):  
Quantitative Research ◽  
Residential Buildings ◽  
Energy Performance ◽  
Climatic Conditions ◽  
Influential Factors ◽  
The Body ◽  
Thermal Mass ◽  
Body Of Knowledge ◽  
Wide Range ◽  
Integrated Performance

Exterior Thermal Mass (eTM) is known to improve building energy and thermal comfort performance. Despite its known benefits, studies to date have not thoroughly addressed the effects of eTM on building environmental performance by considering a wide range of influential factors and various climatic conditions. This paper addresses such a gap in the body of knowledge by conducting a comprehensive and detailed analysis of eTM impacts on residential buildings’ energy performance. Using quantitative research and simulation analyses, this study has found various trends of energy reductions and, in a few cases, energy increases depending upon the location of projects. In fact, the cooling energies are shown to increase of up to 4% for the scenario of 20 cm thickness wall in several locations. Aiming for better energy and design load scenarios, this research has also established the optimal eTM depth to help architects and engineers make informed design decisions with regard to building envelopes, which is particularly important for developing countries with similar climates studied in this paper, where the use of masonry materials is widely common. As for future steps, further exploration of cooling energy increase phenomenon, which was observed for several climates is recommended. Also, coupling eTM with code-required thermal insulation based upon specific climatic locations and evaluate their integrated performance can be considered.

Impact of roof shading on building energy performance in warm & humid climatic places of India

2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Energy Performance ◽  
General Assumption ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Passive Cooling ◽  
Base Case ◽  
U Value ◽  
The Impact

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.

Investigation of the natural ventilation of wind catchers with different geometries in arid region houses

2020 ◽  
Vol 14 (3) ◽  
pp. 7109-7124
Author(s):  
Nasreddine Sakhri ◽  
Younes Menni ◽  
Houari Ameur ◽  
Ali J. Chamkha ◽  
Noureddine Kaid ◽  
...  
Keyword(s):  
Arid Region ◽  
Natural Ventilation ◽  
Reduction Rate ◽  
Internal Flow ◽  
Climatic Conditions ◽  
Maximum Pressure ◽  
Ventilation Technique ◽  
Window Position ◽  
The One ◽  
Flow Velocities

The wind catcher or wind tower is a natural ventilation technique that has been employed in the Middle East region and still until nowadays. The present paper aims to study the effect of the one-sided position of a wind catcher device against the ventilated space or building geometry and its natural ventilation performance. Four models based on the traditional design of a one-sided wind catcher are studied and compared. The study is achieved under the climatic conditions of the South-west of Algeria (arid region). The obtained results showed that the front and Takhtabush’s models were able to create the maximum pressure difference (ΔP) between the windward and leeward of the tower-house system. Internal airflow velocities increased with the increase of wind speed in all studied models. For example, at Vwind = 2 m/s, the internal flow velocities were 1.7, 1.8, 1.3, and 2.5 m/s for model 1, 2, 3, and 4, respectively. However, at Vwind = 6 m/s, the internal flow velocities were 5.6, 5.5, 2.5, and 7 m/s for model 1, 2, 3, and 4, respectively. The higher internal airflow velocities are given by Takhtabush, traditional, front and middle tower models, respectively, with a reduction rate between the tower outlet and occupied space by 72, 42, 36, and 33% for the middle tower, Takhtabush, traditional tower, and the front model tower, respectively. This reduction is due to the due to internal flow resistance. The third part of the study investigates the effect of window (exist opening) position on the opposite wall. The upper, middle and lower window positions are studied and compared. The air stagnation or recirculation zone inside the ventilated space reduced from 55% with the lower window to 46% for the middle window and reached 35% for the upper window position. The Front and Takhtabush models for the one-sided wind catcher with an upper window position are highly recommended for the wind-driven natural ventilation in residential houses that are located in arid regions.

General Trend of Negative Transference Number in Li Salt/Ionic Liquid Mixtures

2019 ◽  
Author(s):  
Nicola Molinari ◽  
Jonathan P. Mailoa ◽  
Boris Kozinsky
Keyword(s):  
Ionic Liquid ◽  
Transference Number ◽  
Liquid Mixtures ◽  
Single Linkage ◽  
Self Diffusion ◽  
Wide Range ◽  
Single Linkage Cluster ◽  
Concentrated Solution ◽  
The One ◽  
Dynamics Simulations

We show that strong cation-anion interactions in a wide range of lithium-salt/ionic liquid mixtures result in a negative lithium transference number, using molecular dynamics simulations and rigorous concentrated solution theory. This behavior fundamentally deviates from the one obtained using self-diffusion coefficient analysis and agrees well with experimental electrophoretic NMR measurements, which accounts for ion correlations. We extend these findings to several ionic liquid compositions. We investigate the degree of spatial ionic coordination employing single-linkage cluster analysis, unveiling asymmetrical anion-cation clusters. Additionally, we formulate a way to compute the effective lithium charge that corresponds to and agrees well with electrophoretic measurements and show that lithium effectively carries a negative charge in a remarkably wide range of chemistries and concentrations. The generality of our observation has significant implications for the energy storage community, emphasizing the need to reconsider the potential of these systems as next generation battery electrolytes.<br>

scholarly journals Modes of Interaction in Naturally Occurring Medical Encounters With General Practitioners: The “One in a Million” Study

2021 ◽  
pp. 104973232199379
Author(s):  
Olaug S. Lian ◽  
Sarah Nettleton ◽  
Åge Wifstad ◽  
Christopher Dowrick
Keyword(s):  
General Practitioners ◽  
Narrative Analysis ◽  
Mode Competition ◽  
General Applicability ◽  
Naturally Occurring ◽  
Wide Range ◽  
The One ◽  
Narrative Mode ◽  
Modes Of Interaction

In this article, we qualitatively explore the manner and style in which medical encounters between patients and general practitioners (GPs) are mutually conducted, as exhibited in situ in 10 consultations sourced from the One in a Million: Primary Care Consultations Archive in England. Our main objectives are to identify interactional modes, to develop a classification of these modes, and to uncover how modes emerge and shift both within and between consultations. Deploying an interactional perspective and a thematic and narrative analysis of consultation transcripts, we identified five distinctive interactional modes: question and answer (Q&A) mode, lecture mode, probabilistic mode, competition mode, and narrative mode. Most modes are GP-led. Mode shifts within consultations generally map on to the chronology of the medical encounter. Patient-led narrative modes are initiated by patients themselves, which demonstrates agency. Our classification of modes derives from complete naturally occurring consultations, covering a wide range of symptoms, and may have general applicability.

scholarly journals Entangling Lattice-Trapped Bosons with a Free Impurity: Impact on Stationary and Dynamical Properties

Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 290
Author(s):  
Maxim Pyzh ◽  
Kevin Keiler ◽  
Simeon I. Mistakidis ◽  
Peter Schmelcher
Keyword(s):  
Structural Changes ◽  
Many Body ◽  
Wide Range ◽  
Entropy Measures ◽  
Particle Level ◽  
The Many ◽  
The One ◽  
Tunneling Dynamics ◽  
The Individual ◽  
Trapped Bosons

We address the interplay of few lattice trapped bosons interacting with an impurity atom in a box potential. For the ground state, a classification is performed based on the fidelity allowing to quantify the susceptibility of the composite system to structural changes due to the intercomponent coupling. We analyze the overall response at the many-body level and contrast it to the single-particle level. By inspecting different entropy measures we capture the degree of entanglement and intraspecies correlations for a wide range of intra- and intercomponent interactions and lattice depths. We also spatially resolve the imprint of the entanglement on the one- and two-body density distributions showcasing that it accelerates the phase separation process or acts against spatial localization for repulsive and attractive intercomponent interactions, respectively. The many-body effects on the tunneling dynamics of the individual components, resulting from their counterflow, are also discussed. The tunneling period of the impurity is very sensitive to the value of the impurity-medium coupling due to its effective dressing by the few-body medium. Our work provides implications for engineering localized structures in correlated impurity settings using species selective optical potentials.

scholarly journals Bio-Inspired Modality Fusion for Active Speaker Detection

2021 ◽  
Vol 11 (8) ◽  
pp. 3397
Author(s):  
Gustavo Assunção ◽  
Nuno Gonçalves ◽  
Paulo Menezes
Keyword(s):  
Superior Colliculus ◽  
Visual Information ◽  
Human Beings ◽  
Validation Process ◽  
Detection Approach ◽  
Wide Range ◽  
Speaker Detection ◽  
The One ◽  
The Brain ◽  
Fusion Ability

Human beings have developed fantastic abilities to integrate information from various sensory sources exploring their inherent complementarity. Perceptual capabilities are therefore heightened, enabling, for instance, the well-known "cocktail party" and McGurk effects, i.e., speech disambiguation from a panoply of sound signals. This fusion ability is also key in refining the perception of sound source location, as in distinguishing whose voice is being heard in a group conversation. Furthermore, neuroscience has successfully identified the superior colliculus region in the brain as the one responsible for this modality fusion, with a handful of biological models having been proposed to approach its underlying neurophysiological process. Deriving inspiration from one of these models, this paper presents a methodology for effectively fusing correlated auditory and visual information for active speaker detection. Such an ability can have a wide range of applications, from teleconferencing systems to social robotics. The detection approach initially routes auditory and visual information through two specialized neural network structures. The resulting embeddings are fused via a novel layer based on the superior colliculus, whose topological structure emulates spatial neuron cross-mapping of unimodal perceptual fields. The validation process employed two publicly available datasets, with achieved results confirming and greatly surpassing initial expectations.

Sign in / Sign up

Export Citation Format

Share Document