scholarly journals Smart Wifi Thermostat-Enabled Thermal Comfort Control in Residences

2020 ◽  
Vol 12 (5) ◽  
pp. 1919 ◽  
Author(s):  
Robert Lou ◽  
Kevin P. Hallinan ◽  
Kefan Huang ◽  
Timothy Reissman
Keyword(s):  
Thermal Comfort ◽  
Energy Savings ◽  
Consumption Data ◽  
Building Geometry ◽  
Temperature And Humidity ◽  
The Mean ◽  
Low Efficiency ◽  
Radiant Temperature ◽  
Nonlinear Autoregressive

The present research leverages prior works to automatically estimate wall and ceiling R-values using a combination of a smart WiFi thermostat, building geometry, and historical energy consumption data to improve the calculation of the mean radiant temperature (MRT), which is integral to the determination of thermal comfort in buildings. To assess the potential of this approach for realizing energy savings in any residence, machine learning predictive models of indoor temperature and humidity, based upon a nonlinear autoregressive exogenous model (NARX), were developed. The developed models were used to calculate the temperature and humidity set-points needed to achieve minimum thermal comfort at all times. The initial results showed cooling energy savings in excess of 83% and 95%, respectively, for high- and low-efficiency residences. The significance of this research is that thermal comfort control can be employed to realize significant heating, ventilation, and air conditioning (HVAC) savings using readily available data and systems.

scholarly journals Field Study Of A Radiant Heating System For Sleep Thermal Comfort And Potential Energy Saving

2021 ◽  
Author(s):  
Christopher L. K. Wang
Keyword(s):  
Potential Energy ◽  
Thermal Comfort ◽  
Energy Saving ◽  
Energy Savings ◽  
Thermal Environment ◽  
Residential Buildings ◽  
Thermal Conditions ◽  
Heating System ◽  
The Body ◽  
Radiant Temperature

As sleep is unconscious, the traditional definition of thermal comfort with conscious judgment does not apply. In this thesis sleep thermal comfort is defined as the thermal condition which enables sleep to most efficiently rejuvenate the body and mind. A comfort model was developed to stimulate the respective thermal environment required to achieve the desired body thermal conditions and a new infrared sphere method was developed to measure mean radiant temperature. Existing heating conditions according to building code conditions during sleeping hours was calculated to likely overheat a sleeping person and allowed energy saving potential by reducing nighttime heating set points. Experimenting with existing radiantly and forced air heated residential buildings, it was confirmed that thermal environment was too hot for comfortable sleep and that the infrared sphere method shows promise. With the site data, potential energy savings were calculated and around 10% of energy consumption reduction may be achieved during peak heating.

scholarly journals Artificial Intelligence Assisted Heating Ventilation and Air Conditioning Control and the Unmet Demand for Sensors: Part 2. Prior Information Notice (PIN) Sensor Design and Simulation Results

Sensors ◽  
2019 ◽  
Vol 19 (15) ◽  
pp. 3440 ◽  
Author(s):  
Chin-Chi Cheng ◽  
Dasheng Lee
Keyword(s):  
Artificial Intelligence ◽  
Energy Consumption ◽  
Air Conditioning ◽  
Prior Information ◽  
Energy Savings ◽  
Theoretical Derivation ◽  
Consumption Data ◽  
Temperature And Humidity ◽  
Hvac Control ◽  
Comparative Results

The study continues the theoretical derivation from Part 1, and the experiment is carried out at a bus station equipped with six water-cooled chillers. Between 2012 and 2017, historical data collected from temperature and humidity sensors, as well as the energy consumption data, were used to build artificial intelligence (AI) assisted heating ventilation and air conditioning (HVAC) control models. The AI control system, in conjunction with a specifically designed prior information notice (PIN) sensor, was used to improve the prediction accuracy. This data collected between 2012 and 2016 was used for AI training and PIN sensor testing. During the hottest week of 2017 in Taiwan, the PIN sensor was used to conduct temperature and humidity data predictions. A model-based predictive control was developed to obtain air conditioning energy consumption data. The comparative results between the predictive and actual data showed that the temperature and humidity prediction accuracies were between 95.5 and 96.6%, respectively. Additionally, energy savings amounting to 39.8% were achieved compared to the theoretical estimates of 44.6%, a difference of less than 5%. These results show that the experimental model supports the theoretical estimations. In the future, a PIN sensor will be installed in a chiller to further verify the energy savings of the AI assisted HVAC control.

scholarly journals The most problematic variable in the course of human-biometeorological comfort assessment — the mean radiant temperature

2011 ◽  
Vol 3 (1) ◽  
Author(s):  
Noémi Kántor ◽  
János Unger
Keyword(s):  
Thermal Comfort ◽  
Short Wave ◽  
Urban Environments ◽  
Outdoor Thermal Comfort ◽  
Radiation Environment ◽  
Wave Radiation ◽  
Mean Radiant Temperature ◽  
Radiation Fluxes ◽  
The Mean ◽  
Radiant Temperature

AbstractThis paper gives a review on the topic of the mean radiant temperature Tmrt, the most important parameter influencing outdoor thermal comfort during sunny conditions. Tmrt summarizes all short wave and long wave radiation fluxes reaching the human body, which can be very complex (variable in spatial and also in temporal manner) in urban settings. Thermal comfort researchers and urban planners need easy and sound methodological approaches to assess Tmrt. After the basics of the Tmrt calculation some of the methods suitable for obtaining Tmrt also in urban environments will be presented.. Two of the discussed methods are based on instruments which measure the radiation fluxes integral (globe thermometer, pyranometer-pyrgeometer combination), and three of the methods are based on modelling the radiation environment with PC software (RayMan, ENVI-met and SOLWEIG).

scholarly journals Thermal comfort of patients in hospital ward areas

1977 ◽  
Vol 78 (1) ◽  
pp. 17-26 ◽  
Author(s):  
R. M. Smith ◽  
A. Rae
Keyword(s):  
Steady State ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Hospital Ward ◽  
Patient Comfort ◽  
Mean Radiant Temperature ◽  
Air Velocity ◽  
Assessment Techniques ◽  
The Mean ◽  
Radiant Temperature

SUMMARYThe patient is identified as being of prime importance for comfort standards in hospital ward areas, other ward users being expected to adjust their dress to suit the conditions necessary for patient comfort. A study to identify the optimum steady state conditions for patient comfort is then described.Although this study raises some doubts as to the applicability of the standard thermal comfort assessment techniques to ward areas, it is felt that its results give a good indication of the steady-state conditions preferred by the patients. These were an air temperature of between 21.5° and 22° C and a relative humidity of between 30% and 70%, where the air velocity was less than 0.1 m/s and the mean radiant temperature was close to air temperature.

scholarly journals DETERMINAÇÃO DO ITU – ÍNDICE DE TEMPERATURA E UMIDADE DA REGIÃO DE ARAGUAÍNA-TO PARA AVALIAÇÃO DO CONFORTO TÉRMICO DE BOVINOS LEITEIROS / DETERMINATION OF ITU - TEMPERATURE AND HUMIDITY INDEX OF THE REGION OF ARAGUAÍNA-TO FOR THE EVALUATION OF THE THERMAL COMFORT OF MILK CATTLE

2020 ◽  
Vol 6 (9) ◽  
pp. 69254-69258
Author(s):  
Clauber Rosanova ◽  
Geovanne Ferreira Rebouças ◽  
Mírian das Mercês Pereira da Silva ◽  
Douglas Messias Lamounier Camargos Rezende ◽  
Alysson Soares da Rocha ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Temperature And Humidity ◽  
Humidity Index

scholarly journals Analysis of Thermal Comfort in an Intelligent Building

2017 ◽  
Vol 13 (1) ◽  
pp. 72-76 ◽  
Author(s):  
Grzegorz Majewski ◽  
Marek Telejko ◽  
Łukasz J. Orman
Keyword(s):  
Thermal Comfort ◽  
Carbon Dioxide Concentration ◽  
Mean Radiant Temperature ◽  
Air Flow Rate ◽  
Point Scale ◽  
Intelligent Building ◽  
University Of Technology ◽  
Measurement Results ◽  
The Mean ◽  
Radiant Temperature

AbstractAnalysis of thermal comfort in the ENERGIS Building, an intelligent building in the campus of the Kielce University of Technology, Poland is the focus of this paper. For this purpose, air temperature, air relative humidity, air flow rate and carbon dioxide concentration were measured and the mean radiant temperature was determined. Thermal sensations of the students occupying the rooms of the building were evaluated with the use of a questionnaire. The students used a seven-point scale of thermal comfort. The microclimate measurement results were used to determine the Predicted Mean Vote and the Predicted Percentage Dissatisfied indices.

scholarly journals APPROACH TO REFURBISHMENT OF TIMBER PRESCHOOL BUILDINGS WITH A VIEW ON ENERGY AND ECONOMIC EFFICIENCY

2019 ◽  
Vol 25 (1) ◽  
pp. 27-40 ◽  
Author(s):  
Nataša Šuman ◽  
Maja Žigart ◽  
Miroslav Premrov ◽  
Vesna Žegarac Leskovar
Keyword(s):  
Economic Efficiency ◽  
Energy Savings ◽  
Main Idea ◽  
Energy Demands ◽  
Functional Quality ◽  
Low Efficiency ◽  
Almost All ◽  
The City

The refurbishment of educational buildings usually involves a variety of measures aiming at reducing energy demands and improving building functionality to achieve higher living comfort. This paper aims to develop an approach for determination of comprehensive refurbishment strategy upon existing preschool buildings in Slovenia from the aspects of energy and economic efficiency. The main idea of the approach is to separate and individually analyse the investments into those related to energy efficiency improvements and those related to improvements of building functional quality through the step-by-step evaluation of individual measures. The proposed approach was applied on the case study of the existing timber preschool building in the city of Maribor. Generally, the highest energy savings are detected only in the case of combination of multiple renovation measures. Moreover, the economic indicators show low efficiency for almost all measures if they are treated separately. Additionally, the analysis reveals that certain measures are totally inefficient in terms of energy, yet they are highly beneficial from the viewpoint of building functional quality, which indicates the importance of the multi-perspective assessment of renovation process. The conclusions of this study can be implemented to similar building types and construction ages in similar climatic and economic environments.

The importance of the calculation of angle factors to determine the mean radiant temperature in temperate climate zone: A university office building case

2021 ◽  
pp. 1420326X2110463
Author(s):  
Mehmet Furkan Özbey ◽  
Cihan Turhan
Keyword(s):  
Thermal Comfort ◽  
Measurement Methods ◽  
Office Building ◽  
Temperate Climate ◽  
Mean Radiant Temperature ◽  
Calculation Methods ◽  
Climate Zone ◽  
The Mean ◽  
Radiant Temperature ◽  
Temperate Climate Zone

Thermal comfort depends on four environmental (air velocity, relative humidity, air temperature, mean radiant temperature) and two personal (clothing insulation and metabolic rate) parameters. Among all parameters, the mean radiant temperature (tr) is the most problematic variable in thermal comfort studies due to its complexity. Measurement methods, calculation methods and assumptions are mostly used to obtain the tr. Researchers mainly prefer to obtain the tr via measurement methods or assumptions due to their easiness compared to the calculation methods. Besides, some researchers use constant values of angle factors in calculation methods. However, using constant values is not proper for every indoor environment, and it causes wrong estimations in the tr and thus the thermal comfort. This paper gives the importance of calculation of angle factors, with an example of a university office building in temperate climate zone, according to the ISO 7726. The angle factors of the room were calculated for a seated occupant from the centre of gravity in three different locations and compared with the constant angle factors. The results indicate that a significant difference (MAPE of 1.02) was found in the tr values, which were obtained by calculation of constant values of angle factors.

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