Research

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20 pages, 4400 KiB

Open AccessArticle

Optimal Synergy between Photovoltaic Panels and Hydrogen Fuel Cells for Green Power Supply of a Green Building—A Case Study

by Raluca-Andreea Felseghi, Ioan Așchilean, Nicoleta Cobîrzan, Andrei Mircea Bolboacă and Maria Simona Raboaca

Sustainability 2021, 13(11), 6304; https://doi.org/10.3390/su13116304 - 02 Jun 2021

Cited by 11 | Viewed by 5334

Abstract

Alternative energy resources have a significant function in the performance and decarbonization of power engendering schemes in the building application domain. Additionally, “green buildings” play a special role in reducing energy consumption and minimizing CO₂ emissions in the building sector. This research [...] Read more.

Alternative energy resources have a significant function in the performance and decarbonization of power engendering schemes in the building application domain. Additionally, “green buildings” play a special role in reducing energy consumption and minimizing CO₂ emissions in the building sector. This research article analyzes the performance of alternative primary energy sources (sun and hydrogen) integrated into a hybrid photovoltaic panel/fuel cell system, and their optimal synergy to provide green energy for a green building. The study addresses the future hydrogen-based economy, which involves the supply of hydrogen as the fuel needed to provide fuel cell energy through a power distribution infrastructure. The objective of this research is to use fuel cells in this field and to investigate their use as a green building energy supply through a hybrid electricity generation system, which also uses photovoltaic panels to convert solar energy. The fuel cell hydrogen is supplied through a distribution network in which hydrogen production is outsourced and independent of the power generation system. The case study creates virtual operating conditions for this type of hybrid energy system and simulates its operation over a one-year period. The goal is to demonstrate the role and utility of fuel cells in virtual conditions by analyzing energy and economic performance indicators, as well as carbon dioxide emissions. The case study analyzes the optimal synergy between photovoltaic panels and fuel cells for the power supply of a green building. In the simulation, an optimally configured hybrid system supplies 100% of the energy to the green building while generating carbon dioxide emissions equal to 11.72% of the average value calculated for a conventional energy system providing similar energy to a standard residential building. Photovoltaic panels account for 32% of the required annual electricity production, and the fuel cells generate 68% of the total annual energy output of the system. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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18 pages, 2160 KiB

Open AccessEditor’s ChoiceArticle

Exploring the Potential of a Gamified Approach to Reduce Energy Use and Carbon Emissions in the Household Sector

by Marta Gangolells, Miquel Casals, Marcel Macarulla and Núria Forcada

Sustainability 2021, 13(6), 3380; https://doi.org/10.3390/su13063380 - 18 Mar 2021

Cited by 7 | Viewed by 2340

Abstract

This paper analyzes the impact of an innovative approach based on gamification to promote reduced energy consumption in social housing. The game was developed and validated under the auspices of the EU-funded project EnerGAware-Energy Game for Awareness of energy efficiency in social housing [...] Read more.

This paper analyzes the impact of an innovative approach based on gamification to promote reduced energy consumption in social housing. The game was developed and validated under the auspices of the EU-funded project EnerGAware-Energy Game for Awareness of energy efficiency in social housing communities in an affordable housing pilot located in Plymouth (United Kingdom). The results showed that the future exploitation of the game holds important energy- and emissions-saving potential. Assuming that the game is distributed freely by European energy providers to their domestic end-users, the game was found to be able to save more than 48.9 secondary terawatt-hours per year (TWh_s) and 18.8 million tons of CO_2e annually, contributing up to around 8% to the target set for the European buildings sector to keep global warming under 2 °C. The results also showed that the game is highly feasible from the energy point of view, even when we consider the energy consumed upstream, due to its low cumulative energy demand and its potential for household energy reduction. The results of this research provide helpful information for private and public stakeholders, as they contribute to determining the sustainability of promoting energy saving through gaming. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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17 pages, 1906 KiB

Open AccessArticle

Architectural Sustainability and Efficiency of Enhanced Waterproof Coating from Utilization of Waterborne Poly (Siloxane-Imide-Urethane) Copolymers on Roof Surfaces

by Yao-Tang Hsu, Wen-Hsin Wang and Wei-Hsi Hung

Sustainability 2020, 12(11), 4411; https://doi.org/10.3390/su12114411 - 28 May 2020

Cited by 5 | Viewed by 2625

Abstract

According to Taiwan’s Ministry of the Interior, from 2017 to 2019, more than 12% of house-purchase disputes were due to water leakage caused by frequent tropical rains, which have long troubled engineers. The thermal stability resistance, water resistance, and ultraviolet resistance of existing [...] Read more.

According to Taiwan’s Ministry of the Interior, from 2017 to 2019, more than 12% of house-purchase disputes were due to water leakage caused by frequent tropical rains, which have long troubled engineers. The thermal stability resistance, water resistance, and ultraviolet resistance of existing polyurethane formulations have been limited by environmental aging. Thus, the lifespan of commercial PU-coated resins (typical PU) for the waterproofing of roof surfaces is merely two to three years. Accordingly, this study proposed the introduction of siloxane and imide groups to produce waterborne poly(urethane-siloxane-imide) (Si-imide-WPU) copolymers to improve the resistance of environmental aging in typical PU. The waterproof coating resin made of Si-imide-WPU copolymers was environmentally friendly, safe to use, and free of organic solvents. The results showed that the optimal Si-imide-WPU-2 sample in the study made improvements on the defects of polyurethane (PU) including its thermal properties, mechanical properties, environmental resistance, and lifespan which could be extended up to 5.4 years. Consequently, the studied Si-imide-WPU copolymers could reduce material waste while enhancing the sustainability and efficiency of the architecture. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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15 pages, 4126 KiB

Open AccessArticle

Evaluating the Properties of a Coating Material with Polycaprolactone-Degradable Fluorinated Silicon-Containing Waterborne Polyurethane

by Yao-Tang Hsu, Wen-Hsin Wang and Wei-Hsi Hung

Sustainability 2020, 12(9), 3745; https://doi.org/10.3390/su12093745 - 05 May 2020

Cited by 8 | Viewed by 2417

Abstract

This study successfully synthesized fluorinated silicon-containing waterborne polyurethanes (FSWPUs) by using polycaprolactone (PCL) diol, 2,2,3,3-Tetrafluoro-1,4-butanediol, and [3-(2-Aminoethylamino)propyl] trimethoxysilane (AEAPTES ). The FSWPU’s particle size was examined using dynamic light scattering. After the FSWPUs were processed into a dry film, their molecular weight and [...] Read more.

This study successfully synthesized fluorinated silicon-containing waterborne polyurethanes (FSWPUs) by using polycaprolactone (PCL) diol, 2,2,3,3-Tetrafluoro-1,4-butanediol, and [3-(2-Aminoethylamino)propyl] trimethoxysilane (AEAPTES ). The FSWPU’s particle size was examined using dynamic light scattering. After the FSWPUs were processed into a dry film, their molecular weight and basic properties were analyzed using gel permeation chromatography (GPC), Fourier-transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (EDS). Additionally, the thermal stability of the FSWPUs was inspected by thermogravimetric analysis and dynamic mechanical analysis. The tensile strength and elongation at the break of the FSWPUs before and after hydrolysis were also analyzed, using a tensile testing machine. Subsequently, FSWPU emulsions were cast between the tiles, and hydrophilicity, hydrophobicity, and surface tension were then measured on a contact-angle measurement instrument. The tensile testing machine was again employed to test the sheer strength of the FSWPUs between the tiles, and a tape test was conducted to analyze their adhesion to the tiles. The results revealed that AEAPTES functional groups can reinforce the thermal stability, tensile strength, and water resistance of FSWPUs. Moreover, the AEAPTES functional groups increased the adhesion of FSWPUs to the tiles and reduced the surface energy of the tiles. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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13 pages, 1795 KiB

Open AccessArticle

Examining the Relationships between Stationary Occupancy and Building Energy Loads in US Educational Buildings–Case Study

by Seungtaek Lee, Wai Oswald Chong and Jui-Sheng Chou

Sustainability 2020, 12(3), 893; https://doi.org/10.3390/su12030893 - 24 Jan 2020

Cited by 3 | Viewed by 2103

Abstract

Building energy systems are designed to handle both permanent and temporary occupants. Permanent occupants are considered the base energy load while temporary occupants are considered a temporary or additional load. Temporary occupancy is potentially the most difficult to design as the number of [...] Read more.

Building energy systems are designed to handle both permanent and temporary occupants. Permanent occupants are considered the base energy load while temporary occupants are considered a temporary or additional load. Temporary occupancy is potentially the most difficult to design as the number of temporary occupants varies more significantly than permanent occupants. This case study was designed to investigate the effect of occupancy on energy loads, i.e. the relationship between occupancy and building energy loads. This study estimated the building occupancy by using existing network infrastructure, such as Wi-Fi and wired Ethernet based on the assumption that the number of Wi-Fi connections and the wired Ethernet traffic were used as a proxy for total and stationary occupancy. The relationships were then examined using correlations and regression analyses. The results showed the following: 1. Stationary occupancy was successfully estimated using the network infrastructure; 2. There was a linear relationship between electricity use and total occupancy (and, thus, the use of network infrastructure); 3. Permanent occupants generated a higher impact on the electricity load than the temporary occupants; 4. There was a logarithmic relationship between electricity use and the Ethernet data traffic (a proxy of permanent occupants); and 5. The statistical and qualitative analyses indicated that there was no significant relationship between occupancy and thermal loads, such as cooling and heating loads. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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11 pages, 373 KiB

Open AccessArticle

High Involvement and Ethical Consumption: A Study of the Environmentally Certified Home Purchase Decision

by Lianne Foti and Avis Devine

Sustainability 2019, 11(19), 5353; https://doi.org/10.3390/su11195353 - 27 Sep 2019

Cited by 8 | Viewed by 3662

Abstract

Sustainable and energy efficient (SEE) attributes in the housing market have become a focus in Canada. Similarly, understanding the consumer’s decision-making process of this high-involvement ethical product has become a burgeoning area for researchers. This study describes the development of the subject, highlighting [...] Read more.

Sustainable and energy efficient (SEE) attributes in the housing market have become a focus in Canada. Similarly, understanding the consumer’s decision-making process of this high-involvement ethical product has become a burgeoning area for researchers. This study describes the development of the subject, highlighting the nature of the ethical decision-making process and how it relates to this known intention–behaviour gap. An observation, followed by two studies consisting of in-depth interviews with real estate agents and sales representatives (n = 15) and home purchasers/consumers (n = 15), were conducted. Transcriptions were analysed qualitatively with NVivo Pro 12 software (NVivo Pro 12, QSR International Pty Ltd, Melbourne, Australia). Inductive thematic analysis revealed two main driving themes: information and trust in seller/realtor. Attribute investment return uncertainty was identified as a theme that affects the strength of the relationship between purchase intention and behaviour, whereas the trust in seller/realtor speaks to how and why this effect occurs. The findings present relationships among the driving factors that were identified by realtors and consumers in the SEE housing market, as well as barriers (investment return uncertainty) that prevent consumers from purchasing high-involvement ethical products. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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12 pages, 4496 KiB

Open AccessArticle

Optimal Control Strategy for Variable Air Volume Air-Conditioning Systems Using Genetic Algorithms

by Nam-Chul Seong, Jee-Heon Kim and Wonchang Choi

Sustainability 2019, 11(18), 5122; https://doi.org/10.3390/su11185122 - 19 Sep 2019

Cited by 13 | Viewed by 3819

Abstract

This study is aimed at developing a real-time optimal control strategy for variable air volume (VAV) air-conditioning in a heating, ventilation, and air-conditioning (HVAC) system using genetic algorithms and a simulated large-scale office building. The two selected control variables are the settings for [...] Read more.

This study is aimed at developing a real-time optimal control strategy for variable air volume (VAV) air-conditioning in a heating, ventilation, and air-conditioning (HVAC) system using genetic algorithms and a simulated large-scale office building. The two selected control variables are the settings for the supply air temperature and the duct static pressure to provide optimal control for the VAV air-conditioning system. Genetic algorithms were employed to calculate the optimal control settings for each control variable. The proposed optimal control conditions were evaluated according to the total energy consumption of the HVAC system based on its component parts (fan, chiller, and cold-water pump). The results confirm that the supply air temperature and duct static pressure change according to the cooling load of the simulated building. Using the proposed optimal control variables, the total energy consumption of the building was reduced up to 5.72% compared to under ‘normal’ settings and conditions. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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Review

Jump to: Research

21 pages, 1663 KiB

Open AccessReview

Indoor Air Quality Monitoring Systems for Enhanced Living Environments: A Review toward Sustainable Smart Cities

by Gonçalo Marques, Jagriti Saini, Maitreyee Dutta, Pradeep Kumar Singh and Wei-Chiang Hong

Sustainability 2020, 12(10), 4024; https://doi.org/10.3390/su12104024 - 14 May 2020

Cited by 48 | Viewed by 7643

Abstract

Smart cities follow different strategies to face public health challenges associated with socio-economic objectives. Buildings play a crucial role in smart cities and are closely related to people’s health. Moreover, they are equally essential to meet sustainable objectives. People spend most of their [...] Read more.

Smart cities follow different strategies to face public health challenges associated with socio-economic objectives. Buildings play a crucial role in smart cities and are closely related to people’s health. Moreover, they are equally essential to meet sustainable objectives. People spend most of their time indoors. Therefore, indoor air quality has a critical impact on health and well-being. With the increasing population of elders, ambient-assisted living systems are required to promote occupational health and well-being. Furthermore, living environments must incorporate monitoring systems to detect unfavorable indoor quality scenarios in useful time. This paper reviews the current state of the art on indoor air quality monitoring systems based on Internet of Things and wireless sensor networks in the last five years (2014–2019). This document focuses on the architecture, microcontrollers, connectivity, and sensors used by these systems. The main contribution is to synthesize the existing body of knowledge and identify common threads and gaps that open up new significant and challenging future research directions. The results show that 57% of the indoor air quality monitoring systems are based on Arduino, 53% of the systems use Internet of Things, and WSN architectures represent 33%. The CO₂ and PM monitoring sensors are the most monitored parameters in the analyzed literature, corresponding to 67% and 29%, respectively. Full article

(This article belongs to the Special Issue Next Energy Efficiency Solutions for Sustainable Buildings)

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