Sustainability

Research

Jump to: Other

15 pages, 2641 KiB

Open AccessArticle

Performance of an Adsorptive Heat-Moisture Regenerator Based on Silica Gel–Sodium Sulphate

by Elena Belyanovskaya, Miroslav Rimár, Roman D. Lytovchenko, Miroslav Variny, Kostyantyn M. Sukhyy, Oleksandr O. Yeromin, Mikhailo P. Sykhyy, Elena M. Prokopenko, Irina V. Sukha, Mikhailo V. Gubinskyi and Ján Kizek

Sustainability 2020, 12(14), 5611; https://doi.org/10.3390/su12145611 - 13 Jul 2020

Cited by 7 | Viewed by 2346

Abstract

The performance of an adsorptive heat-moisture regenerator based on a silica gel–sodium sulphate composite adsorbent was studied. The correlation between the adsorbent composition and structural characteristics of the laboratory-scale device was investigated. An algorithm for the calculation of the efficiency factors of the [...] Read more.

The performance of an adsorptive heat-moisture regenerator based on a silica gel–sodium sulphate composite adsorbent was studied. The correlation between the adsorbent composition and structural characteristics of the laboratory-scale device was investigated. An algorithm for the calculation of the efficiency factors of the adsorptive regenerator was further developed. The suggested algorithm calculates the operational parameters, including the temperatures, humidities and volumetric flows of internal and external air, and estimates the regenerator’s performance via temperature and moisture efficiency factors, total adsorption and time needed to achieve maximum adsorption, air pressure loss and fan power input. The validity of the calculation results obtained using the proposed algorithm was confirmed experimentally. Temperature efficiency factor, air pressure loss and fan power consumption are crucial parameters for the estimation of the optimal operating regime of an adsorptive heat-moisture regenerator. The correlation between meteorological conditions and efficiency factors was assessed and applied in a simulation of residential house-scale air conditioning unit operation. Maximal values of temperature efficiency factor were found at internal and external air temperatures of 15 to 20 °C and −5 to 0 °C, respectively. Moisture efficiency factors were observed to reach their maximum at the absolute humidities of external and internal air of 4.0 to 5.0 g/m³ and 2.75 to 3.0 g/m³, respectively. The fan power consumption of the adsorptive heat-moisture regenerator was found to be comparable to or even lower than that of commercial air conditioning units used in comparably voluminous interiors. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

17 pages, 6955 KiB

Open AccessArticle

Estimation of Direct and Indirect Household CO₂ Emissions in 49 Japanese Cities with Consideration of Regional Conditions

by Yujiro Hirano, Tomohiko Ihara, Masayuki Hara and Keita Honjo

Sustainability 2020, 12(11), 4678; https://doi.org/10.3390/su12114678 - 8 Jun 2020

Cited by 12 | Viewed by 4097

Abstract

We conducted a detailed estimation of direct and indirect CO₂ emissions related to multi-person households in 49 Japanese cities. Direct energy consumption was decomposed into energy use in order to consider the relationship with regional conditions. The results showed that CO₂ [...] Read more.

We conducted a detailed estimation of direct and indirect CO₂ emissions related to multi-person households in 49 Japanese cities. Direct energy consumption was decomposed into energy use in order to consider the relationship with regional conditions. The results showed that CO₂ emissions from direct energy consumption were almost as large as indirect CO₂ emissions induced by consuming products and services, suggesting that lifestyle improvements are important for both energy savings and reducing CO₂ emissions relating to product and service consumption. In addition, CO₂ emissions from direct energy consumption varied widely between cities, making them susceptible to regional conditions. We also calculated CO₂ emissions from direct energy consumption and examined the regional conditions for individual forms of energy use. CO₂ emissions were higher in cold regions and lower in larger cities. In Japan, large cities are often located in relatively warm areas, so we conducted an analysis to distinguish the effects of climatic conditions from those of urbanization. This analysis allowed us to clarify the effects of regional conditions on factors such as heating/cooling and the ratio of detached houses to apartments. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

23 pages, 4290 KiB

Open AccessArticle

Temporal and Spatial Variability of Carbon Emission Intensity of Urban Residential Buildings: Testing the Effect of Economics and Geographic Location in China

by Qingwei Shi, Jingxin Gao, Xia Wang, Hong Ren, Weiguang Cai and Haifeng Wei

Sustainability 2020, 12(7), 2695; https://doi.org/10.3390/su12072695 - 30 Mar 2020

Cited by 17 | Viewed by 3075

Abstract

The role of urban residential buildings (URBs) in the carbon reduction goal of China is becoming increasingly important because of the rising energy consumption and carbon emission of such buildings in the region. Considering the increasing spatial interaction of the carbon emission of [...] Read more.

The role of urban residential buildings (URBs) in the carbon reduction goal of China is becoming increasingly important because of the rising energy consumption and carbon emission of such buildings in the region. Considering the increasing spatial interaction of the carbon emission of URBs (URBCE) in the region, this study investigates the influence of climate and economic factors on the URBCE in North and South China. First, the URBCE is calculated by using a decomposition energy balance table based on the carbon emission coefficient of electric and thermal power, thereby improving the estimation of the basic data of URBCE. Second, the influence of economic and climatic factors on the URBCE intensity in 30 provinces of China is explored by using a spatial econometric model. Results show that the URBCE intensity in China had a spatial autocorrelation from 2000 to 2016. Climatic and economic factors have great differences in the degree and direction of influencing the URBCE intensity in the country. Formulating emission reduction policies for climate or economic zones is more scientific and effective than developing national policies. Among these factors, urbanization rate, climate, and GDP per capita have a significant positive impact on the URBCE intensity in the region, whereas other factors have varying degrees of negative impact. In addition, climate, consumption level, and building area have significant spatial spillover effects on URBCE intensity, whereas other factors do not pass the significance test. Relevant conclusions should be given special attention by policymakers. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

22 pages, 3388 KiB

Open AccessArticle

Energy Savings on an Industrial Building in Different Climate Zones: Envelope Analysis and PV System Implementation

by Carlos A. Espino-Reyes, Naghelli Ortega-Avila and Norma A. Rodriguez-Muñoz

Sustainability 2020, 12(4), 1391; https://doi.org/10.3390/su12041391 - 13 Feb 2020

Cited by 6 | Viewed by 2545

Abstract

The energy market in Mexico is facing changes due to the incorporation of clean energy certificates (CEL) on the Electric Industry Law (LIE, Ley de la Industria Electrica). One of the aims is to increase the percentage of clean energy use in the [...] Read more.

The energy market in Mexico is facing changes due to the incorporation of clean energy certificates (CEL) on the Electric Industry Law (LIE, Ley de la Industria Electrica). One of the aims is to increase the percentage of clean energy use in the national energy matrix. Consequently, the integration of energy efficiency strategies prior to the incorporation of renewables has become essential at different levels. Industrial buildings have significant heat gains and losses through the envelope, mainly due to their vast surface and simple construction systems. This work analyses the typical envelopes of industrial buildings in Mexico and the effect of industrial rooftop photovoltaic (PV) systems over the annual energy consumption. It was found that for temperate climates, the best option would be to insulate the roof. For cities with warm climates, the best approach is to implement a cool roof on a non-insulated layer or to simply insulate the roof. Additionally, the industrial buildings with metallic roofs situated in warmer climates would benefit the most from the implementation of rooftop PV systems. After all, the results point out that the decrease in the required CELs would not influence the savings. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

16 pages, 1992 KiB

Open AccessArticle

Application of Building Performance Simulation to Design Energy-Efficient Homes: Case Study from Saudi Arabia

by Wahhaj Ahmed, Muhammad Asif and Farajallah Alrashed

Sustainability 2019, 11(21), 6048; https://doi.org/10.3390/su11216048 - 31 Oct 2019

Cited by 31 | Viewed by 6100

Abstract

The per capita energy usage in Saudi Arabia is almost three times higher than the global average. A major contributor is the residential sector which consumes almost 50% of the total national energy consumption every year. Environmental and economic pressures along with the [...] Read more.

The per capita energy usage in Saudi Arabia is almost three times higher than the global average. A major contributor is the residential sector which consumes almost 50% of the total national energy consumption every year. Environmental and economic pressures along with the Saudi Vision 2030 reform program advocate for an improvement in energy consumption patterns. For a sustainable residential sector, energy-efficient solutions should be adopted in the design process preferably based on building performance simulation (BPS). This study investigates the existing status and future prospects of BPS in the construction industry of Saudi Arabia. A survey has been carried out with building industry professionals to investigate the existing practices in terms of use of BPS. Energy and environmental savings achievable through application of BPS have been estimated by modelling a typical residential villa as a case study. The results indicate that presently BPS is not being adequately applied by the building industry and a number of barriers exist which need to be addressed. The case study simulation indicates that electricity consumption of a villa based on a BPS-based design process is 51.3% less than the existing typical residential villa. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

30 pages, 4079 KiB

Open AccessArticle

Photovoltaic Expansion-Limit through a Net Energy Metering Scheme for Selected Malaysian Public Hospitals

by Mohd Effendi Amran, Mohd Nabil Muhtazaruddin, Firdaus Muhammad-Sukki, Nurul Aini Bani, Tauran Zaidi Ahmad Zaidi, Khairul Azmy Kamaluddin and Jorge Alfredo Ardila-Rey

Sustainability 2019, 11(18), 5131; https://doi.org/10.3390/su11185131 - 19 Sep 2019

Cited by 7 | Viewed by 4034

Abstract

This paper presents an optimization approach in determining the expansion-limit of Renewable Distributed Generation (DG) capacity through a Net Energy Metering (NEM) scheme specifically for selected Malaysian public hospitals. In this study, the total line loss reduction was analyzed and set as the [...] Read more.

This paper presents an optimization approach in determining the expansion-limit of Renewable Distributed Generation (DG) capacity through a Net Energy Metering (NEM) scheme specifically for selected Malaysian public hospitals. In this study, the total line loss reduction was analyzed and set as the main objective function in the optimization process where an acceptance region for DG extensiveness was proposed via the lower total line loss outcome value. Solar photovoltaic (PV)-type DG unit (PV-DG) was identified as the type of DG used in this paper. Artificial Bee Colony (ABC) algorithm was chosen to alleviate such PV-DG optimization. The distribution network uses a bus and line data setup from the three selected Malaysian public hospitals prior to three different levels, i.e., National, State, and District level hospitals. MATLAB simulation result showed the PV-DG expansion capacity towards bigger scale and location bounded by the U-trajectory shape theory which resulted in a contradiction between NEM current maximum capacity requirement and actual PV-DG expansion-limit. These limitations were also found to be different among three different level hospitals, and the expansion-limit was tailored by their own distribution network parameters. Thus, this paper provides technical justification and gives the best option to the renewable energy (RE) developer for more effective PV-DG integration through the utilization of a NEM scheme. The importance of the study is portrayed in-depth towards achieving a more sensible and accurate way of estimating the outcome. This will encourage developers, building owners, and users in participating towards achieving potential benefits both in monetary and power system reliability improvement, specifically for Malaysian public hospital applications. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Figure 1

16 pages, 2781 KiB

Open AccessArticle

A Comparison of Energy Efficiency Certification in Housing: A Study of the Chilean and Spanish Cases

by Francisco Sanhueza-Durán, José M. Gómez-Soberón, Claudia Valderrama-Ulloa and Felipe Ossio

Sustainability 2019, 11(17), 4771; https://doi.org/10.3390/su11174771 - 2 Sep 2019

Cited by 3 | Viewed by 2853

Abstract

Faced with implementing policies that seek to improve the energy efficiency of housing and reduce the impact of CO₂ emissions, several countries are introducing (unilaterally or by international agreement) energy certification systems that allow the effects of these policies to be evaluated. [...] Read more.

Faced with implementing policies that seek to improve the energy efficiency of housing and reduce the impact of CO₂ emissions, several countries are introducing (unilaterally or by international agreement) energy certification systems that allow the effects of these policies to be evaluated. This study aims to compare the energy efficiency certification systems in Spain and Chile, identifying convergent and divergent parameters, enabling the existing gaps to be identified and improvements noted for both systems. To do so, 20 sample dwellings in Santiago de Chile were evaluated, along with the local calculating tools in both countries. The analysis considered the aspects of regulation, its reach, the characterization of the models and the necessary indicators. The comparison identified, among others, differences such as obligatory implementation of the system, a study of the existing buildings in the focus area, the prevailing indicators for evaluating the effects of the buildings, the low incidence of mixed energy systems in the Chilean system and the possibility of proposing and evaluating improvements in the Spanish system. As a result, higher energy requirements and greater CO₂ emissions were identified in the Chilean system, reaching differences of 42 kWh/m²/year in consumption and 14 kgCO₂/ m²/year in emissions with regard to the Spanish qualification. The results of this comparison have facilitated the identification of improvements that will increase the evaluation standards of the Chilean system. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

► Show Figures

Graphical abstract

Other

Jump to: Research

3 pages, 157 KiB

Open AccessCommentary

Role of Energy Conservation and Management in the 4D Sustainable Energy Transition

by Muhammad Asif

Sustainability 2020, 12(23), 10006; https://doi.org/10.3390/su122310006 - 30 Nov 2020

Cited by 24 | Viewed by 2603

Abstract

In the twenty first century, the world is witnessing an unprecedented energy transition. This sustainability-driven transition, also termed the sustainable energy transition or low carbon transition, has four major dimensions: decarbonisation, decreased use, decentralisation, and digitalisation. Decarbonisation and decreased use of energy are [...] Read more.

In the twenty first century, the world is witnessing an unprecedented energy transition. This sustainability-driven transition, also termed the sustainable energy transition or low carbon transition, has four major dimensions: decarbonisation, decreased use, decentralisation, and digitalisation. Decarbonisation and decreased use of energy are already well established dimensions of the sustainable energy transition. Decreased use of energy through energy conservation and management (ECM) offers wide ranging benefits across all energy consuming sectors, i.e., buildings, industry, and transportation. The building sector, accounting for almost 40% of the world’s total energy consumption, is particularly conducive to ECM. Estimates suggest that with the reliable and commercially available solutions, energy demand in both new and existing buildings can be reduced by 30 to 80%. Full article

(This article belongs to the Special Issue Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices)

Journal Menu

Journal Browser

Energy Conservation and Management in Buildings: Technologies, Policies and Best Practices

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (8 papers)

Research

Other

Further Information

Guidelines

MDPI Initiatives

Follow MDPI