Assessment of the impact of HVAC system configuration and control zoning on thermal comfort and energy efficiency in flexible office spaces

2020 ◽  
Vol 212 ◽  
pp. 109785 ◽  
Author(s):  
Jasmin Anika Gärtner ◽  
Francesco Massa Gray ◽  
Thomas Auer
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Hvac System ◽  
System Configuration ◽  
And Control ◽  
The Impact

scholarly journals Investigate the impact of a low u-value framing condition and an insulated curb condition at cantileverd concrete balcony slabs in high-rise MURBS

2021 ◽  
Author(s):  
Chafik Murad
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Thermal Performance ◽  
Concrete Surface ◽  
Technical Performance ◽  
High Rise ◽  
Surface Temperatures ◽  
U Value ◽  
Thermal Bridging ◽  
The Impact

Cantilevered concrete balcony slabs are being investigated in high-rise (MURBs) to control thermal bridging in terms of energy efficiency and thermal comfort where the use of a proprietary thermal break was the prime application as a solution to improving energy efficiency. This MRP investigated the thermal performance of using a lower U-value framed glazing condition and an insulated curb condition and developed assemblies in scenarios that were simulated in THERM, and focused on the technical performance of thermal comfort benefit of insulated curb condition of 12.7 mm thick EPS. Concrete surface temperatures were significantly increased in values from 4.8 °C to 9.6 °C and from 6.2 °C to 10.0 °C above balcony slab and from 6.7 °C to 10.8 °C below slab when an insulated curb condition was used in conventional scenarios and in a lower U-value framed condition scenario with no proprietary thermal break added. U-values are reduced 10% to 18% for the upper surface of balcony slab and 4% reduction of the overall U-values when an insulated curb condition is incorporated.

scholarly journals Study of Losses and Energy Efficiency of Hydrostatic Drives with Hydraulic Cylinder

2018 ◽  
Vol 25 (4) ◽  
pp. 114-128 ◽  
Author(s):  
Grzegorz Skorek
Keyword(s):  
Energy Efficiency ◽  
Control Valve ◽  
Hydraulic Cylinder ◽  
Mathematical Tool ◽  
Hydraulic Systems ◽  
Motor Speed ◽  
Accurate Analysis ◽  
Hydrostatic Transmissions ◽  
And Control ◽  
The Impact

Abstract Energy efficiency of hydrostatic transmissions, and especially efficiencies of drives with motor speed controlled by throttle, as well as efficiency of hydraulic servomechanisms can in fact be higher than the efficiency values most frequently given by the respective literature in this field. With the progress achieved in recent years in the development of hydraulic systems it is becoming necessary to develop methods for precise energy efficiency calculation of such systems. It is difficult to imagine that more and more, better and better machines and control elements could be used without the possibility of a mathematical tool at our disposal to enable an accurate analysis and assessment of behavior of the system in which such machines and control elements have been applied. The paper discusses energy savings using mathematical model of losses in elements, the energy efficiency of the system. There are possibilities to reduce energy losses in proportional control systems (in the pump, in the throttle control unit, especially in the cylinder), and thus to improve the energy efficiency of the throttling manifold. The considerations allow for comparison of the loss power resulting from the applied hydraulic control structure of the hydraulic cylinder and the power consumed by the pump from the electric motor that drives it, the power necessary to provide pump-driven hydraulic cylinder. The article shows the impact on the output (useful) power consumed in the considered systems, and the impact on the power consumed of the loss power in the individual elements. The paper presents also formulas of loss power, formulas of energy efficiency connected with investigated hydrostatic drives, two schematic diagrams of hydraulic systems, their principle of operation and problems of studying losses in elements and energy efficiency characteristics of systems consisting of a feed assembly, control set and cylinder. It also includes a subject matter connected with an energy loss power of hydrostatic systems with hydraulic cylinder controlled by proportional directional control valve. Diagrams of loss power of two hydraulic systems worked at the same parameters of speed and load of a cylinder, which were different due to structure and ability of energy saving, were presented and compared.

scholarly journals Improving the energy efficiency of an office building by applying a thermal comfort model

2021 ◽  
Vol 2069 (1) ◽  
pp. 012172
Author(s):  
G Kiki ◽  
P André ◽  
A Houngan ◽  
C Kouchadé
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Electrical Energy ◽  
Office Building ◽  
Tropical Regions ◽  
Comfort Index ◽  
The Hours ◽  
Air Conditioning Systems ◽  
Thermal Comfort Model ◽  
The Impact

Abstract The building represents one of the main actors of global warming of the planet because of the significant amounts of energy consumed. In Benin, 44,38% of electrical energy is consumed by office and service buildings. This is explained by the excessive use of air conditioning systems due to the lack of a thermal comfort index specific to the region. This work therefore focuses on assessing the impact of the choice of a thermal comfort model on the energy efficiency of buildings. For this purpose, an office building was chosen in the south of Benin and comfort surveys were conducted among the occupants. The model selected for this purpose is the adaptive model developed by López-Pérez and al. for air-conditioned buildings in humid tropical regions. Subsequently, a monitoring campaign of meteorological, hygrothermal and energetic data of the building was carried out during six months. The results obtained show that the average temperature of the offices (Tf ≈ 24°C) during the hours of occupancy is relatively lower than the comfort temperature determined with the model (Tc = 26.2°C). Moreover, the different simulations carried out under TRNSYS by substituting the office temperatures by the comfort temperature show a reduction of about 20% of the building’s energy consumption. This shows the importance of the comfort model of López-Pérez and al. in improving the energy efficiency of the building.

scholarly journals Effect of Different HVAC Control Strategies on Thermal Comfort and Adaptive Behavior in High-Rise Apartments

2021 ◽  
Vol 13 (21) ◽  
pp. 11767
Author(s):  
Jihye Ryu ◽  
Jungsoo Kim
Keyword(s):  
Thermal Comfort ◽  
Adaptive Behavior ◽  
Control Strategies ◽  
Control Measures ◽  
Hvac System ◽  
Comfort Zone ◽  
Residential Sector ◽  
High Rise ◽  
Hvac Control ◽  
The Impact

In the residential sector, householders play an active role in regulating the indoor climate via diverse control measures such as the operation of air-conditioners or windows. The main research question asked in this paper is whether control decisions made by householders are rational and effective in terms of achieving comfort and energy efficiency. Based on a field study in South Korea, this paper explores how a HVAC control strategy for high-rise apartment buildings can affect occupant comfort and adaptive behavior. Two different control strategies: (1) occupant control (OC), where occupants were allowed to freely operate the HVAC system and (2) comfort-zone control (CC), where the operation of the HVAC system was determined by the researcher, based on a pre-defined comfort zone, were applied to, and tested within the participating households in summer. The impact of the two control strategies on indoor thermal environments, thermal comfort, and occupant adaptive behavior were analyzed. We find that the CC strategy is more energy/comfort efficient than OC because: (1) comfort was be achieved at a higher indoor temperature, and (2) unnecessary control behaviors leading to cooling load increase can be minimized, which have major implications for energy consumption reduction in the residential sector.

scholarly journals An assessment of the impact of selected construction materials on the life cycle energy performance and thermal comfort in buildings

2021 ◽  
Author(s):  
◽  
Rajesh Haripersad
Keyword(s):  
South Africa ◽  
Energy Efficiency ◽  
Life Cycle ◽  
Thermal Comfort ◽  
Thermal Performance ◽  
Energy Efficient ◽  
Construction Materials ◽  
Embodied Energy ◽  
Energy Usage ◽  
The Impact

South Africa is a developing country with various construction projects that are being undertaken both by government and the private sector. The requirements for the construction of energy-efficient buildings as well as the selection methods for providing construction materials have hence become important. Energy efficiency improvements needs to be implemented in the construction of these buildings in order to decrease energy usage and costs and provide more comfortable conditions for its occupants. Previous studies revealed that most of the focus for improving energy efficiency in buildings has been on their operational emissions. It is estimated that about 30% of all energy consumed throughout the lifetime of a building is utilized as embodied energy (this percentage varies based on factors such as age of building, climate and materials). In the past this percentage was much lower, but with increased emphasis placed on reducing operational emissions (such as energy efficiency improvements in heating and cooling systems), the embodied energy contribution has become more significant. Hence, it is important to employ a life-cycle carbon framework in analysing the carbon emissions in buildings. The study aims to augment energy efficiency initiatives by showcasing energy reduction strategies for buildings. The study assessed the thermal performance of selected construction materials by analysing different buildings using energy modelling program, EnergyPlus and TRNSYS. The parametric study was set in the central plateau region of South Africa and was performed to determine appropriate energy efficiency improvements that can be implemented for maximum savings. A life cycle cost analysis was performed on the selected improvements. The models created are representative of the actual buildings when simulated data is compared to recorded data from these buildings. Results showed a significant variation in energy and construction costs with varying construction materials over the buildings’ life cycle. Findings suggest that there is a significant reduction in energy usage when simple efficiency measures are implemented. The study recommends the use of different energy efficient building materials and the implementation of passive interventions in the constructing of buildings; the thermal performance of a building be optimized to ensure thermal comfort and the developed model be adopted for use in the engineering and construction industry for the reduction of energy consumption.

scholarly journals Energy Efficiency Metrics of University Data Centers

2018 ◽  
Vol 1 (2) ◽  
pp. 64
Author(s):  
Lenonel Hernandez ◽  
Genett Jimenez ◽  
Piedad Marchena
Keyword(s):  
Energy Efficiency ◽  
Cloud Computing ◽  
Internet Of Things ◽  
Large Volume ◽  
Data Center ◽  
Data Centers ◽  
Monitoring And Control ◽  
And Control ◽  
The Impact ◽  
Computing Infrastructure

The data centers are fundamental pieces in the network and computing infrastructure, and evidently today more than ever they are relevant. Since they support the processing, analysis, assurance of the data generated in the network and by the applications in the cloud, which every day increases its volume thanks to technologies such as Internet of Things, Virtualization, and cloud computing, among others. Precisely the management of this large volume of information makes the data centers consume a lot of energy, generating great concern to owners and administrators. Green Data Centers offer a solution to this problem, reducing the impact produced by the data centers in the environment, through the monitoring and control of these. The metrics are the tools that allow us to measure in our case the energy efficiency of the data center and evaluate if it is friendly to the environment. These metrics will be applied to the data centers of the ITSA University Institution, Barranquilla and Soledad campus, and the analysis of these will be carried out. In previous research, the most common metric (PUE) was analyzed to measure the efficiency of the data centers, to verify if the University's data center is friendly to the environment. It is planned to extend this study by carrying out an analysis of several metrics to conclude which is the most efficient and which allows defining the guidelines to update or convert the data center in a friendly environment. 

scholarly journals Study the Pattern of Land Occupied in Residential Components Based on the Theory of Heat Due to Human Thermal Comfort in Kerman-Iran

2015 ◽  
Vol 10 (Special-Issue1) ◽  
pp. 56-64
Author(s):  
Iman Iranmanesh ◽  
Ima Etminan ◽  
Minoo Iranmanesh
Keyword(s):  
Thermal Comfort ◽  
Indoor Environment ◽  
Land Occupation ◽  
Thermal Index ◽  
Fossil Energy ◽  
Open Environment ◽  
Human Thermal Comfort ◽  
And Control ◽  
The Impact ◽  
East West

Due to the reduction of fossil energy sources, taking a step towards reducing energy consumption, leads to saving resources and protecting the environment will be limited. In this way, taking advantage of the potential energy of the environment is the most logical way to achieve thermal comfort. On the other hand, as that human activities take place in both open and enclosed environment, the impact of climate on human physiology is different in this two environments. So, directly in the various elements of the free space affect to the man directly. Further, the climate of open environment has a major impact on the climate of indoor environment. The residential area next to the outdoor units, needs to provide comfort at a demand for more. Further, In the hot and dry air of Kerman, more consideration is needed. therefore try to assess the impact on indoor outdoor view of the position of occupied land and from the standpoint of conventional thermal index (Mahoney, Oleg, Giovannini) on patterns in Kerman was the dominant pattern of issue. By Using the harvest field, in Kerman, 4 leitmotif of land occupation for housing units are discovered. Along with, the thermal index for Kerman localization and the results on the shape of the occupation of the land test and control also its suggested to consider two-way stretch & east-west courtyard, vegetation and create shading on the ground as a model for the occupation of land.

HEAC and THYCS Projects

2006 ◽  
Author(s):  
Stefano Mola ◽  
Stefania Martini ◽  
Maria Laura Parodi ◽  
Giulio Lo Presti ◽  
Carloandrea Malvicino
Keyword(s):  
Thermal Comfort ◽  
Fuel Consumption ◽  
Air Conditioning ◽  
Environmental Concern ◽  
Research Activity ◽  
Air Conditioning System ◽  
Rapid Action ◽  
Hot Weather ◽  
And Control ◽  
The Impact

Due to its more and more widespread diffusion, Air Conditioning (A/C) systems in automobiles will face two main challenges in the near future: to improve the evaluation and control of perceived thermal comfort, and to reduce the fuel consumption increase due to its use (up to 70% in urban operation under hot weather [1]). In view of future regulations and heightening environmental concern, rapid action is needed to reduce such negative A/C impact. Moreover, the A/C system has also an important role in safety, since it has to assure the driver’s visibility by avoiding fogging formation on the windshield in any condition of use. This function has to be assured in the most reliable and automatic way, minimising the interaction of the driver with the A/C system itself. The two research projects described in the present paper have the following goals: • To improve the perceived thermal comfort evaluation. • To lower the impact of air conditioning system on fuel consumption. • To detect incipient fogging conditions in a reliable and predictive way. The research activity has been performed with the following constraints: • To minimize the number of sensors. • To reduce the cost of the air conditioning system.

scholarly journals Investigate the impact of a low u-value framing condition and an insulated curb condition at cantileverd concrete balcony slabs in high-rise MURBS

2021 ◽  
Author(s):  
Chafik Murad
Keyword(s):  
Energy Efficiency ◽  
Thermal Comfort ◽  
Thermal Performance ◽  
Concrete Surface ◽  
Technical Performance ◽  
High Rise ◽  
Surface Temperatures ◽  
U Value ◽  
Thermal Bridging ◽  
The Impact

Cantilevered concrete balcony slabs are being investigated in high-rise (MURBs) to control thermal bridging in terms of energy efficiency and thermal comfort where the use of a proprietary thermal break was the prime application as a solution to improving energy efficiency. This MRP investigated the thermal performance of using a lower U-value framed glazing condition and an insulated curb condition and developed assemblies in scenarios that were simulated in THERM, and focused on the technical performance of thermal comfort benefit of insulated curb condition of 12.7 mm thick EPS. Concrete surface temperatures were significantly increased in values from 4.8 °C to 9.6 °C and from 6.2 °C to 10.0 °C above balcony slab and from 6.7 °C to 10.8 °C below slab when an insulated curb condition was used in conventional scenarios and in a lower U-value framed condition scenario with no proprietary thermal break added. U-values are reduced 10% to 18% for the upper surface of balcony slab and 4% reduction of the overall U-values when an insulated curb condition is incorporated.

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