scholarly journals Research on Best Solution for Improving Indoor Air Quality and Reducing Energy Consumption in a High-Risk Radon Dwelling from Romania

2021 ◽  
Vol 18 (23) ◽  
pp. 12482
Author(s):  
Ion-Costinel Mareș ◽  
Tiberiu Catalina ◽  
Marian-Andrei Istrate ◽  
Alexandra Cucoș ◽  
Tiberius Dicu ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Heat Recovery ◽  
Natural Ventilation ◽  
High Efficiency ◽  
Ventilation System ◽  
Radon Level

The purpose of this article is the assessment of energy efficiency and indoor air quality for a single-family house located in Cluj-Napoca County, Romania. The studied house is meant to be an energy-efficient building with thermal insulation, low U-value windows, and a high efficiency boiler. Increasing the energy efficiency of the house leads to lower indoor air quality, due to lack of natural ventilation. As the experimental campaign regarding indoor air quality revealed, there is a need to find a balance between energy consumption and the quality of the indoor air. To achieve superior indoor air quality, the proposed mitigation systems (decentralized mechanical ventilation with heat recovery combined with a minimally invasive active sub-slab depressurization) have been installed to reduce the high radon level in the dwelling, achieving an energy reduction loss of up to 86%, compared to the traditional natural ventilation of the house. The sub-slab depressurization system was installed in the room with the highest radon level, while the local ventilation system with heat recovery has been installed in the exterior walls of the house. The results have shown significant improvement in the level of radon decreasing the average concentration from 425 to 70 Bq/m 3, respectively the carbon dioxide average of the measurements being around 760 ppm. The thermal comfort improves significantly also, by stabilizing the indoor temperature at 21 °C, without any important fluctuations. The installation of this system has led to higher indoor air quality, with low energy costs and significant energy savings compared to conventional ventilation (by opening windows).

scholarly journals Indoor air quality improvement in natural ventilation using a fuzzy logic controller

2020 ◽  
pp. 1-19
Author(s):  
Cezary Kulis ◽  
Jarosław Müller
Keyword(s):  
Fuzzy Logic ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Optical Sensors ◽  
Natural Ventilation ◽  
Fuzzy Logic Controller ◽  
Ventilation System ◽  
Raspberry Pi ◽  
Physical Parameters

The aim of the research was to design and validate the prototype of a device developed to improve the quality of indoor air by supporting the natural ventilation in building. A CO2 sensor and thermo-hygrometer were used to measure the physical parameters of the indoor air. The developed device is based on the Raspberry Pi single-board-computer (SBC) and optical sensors. The prototype casing was made using 3D printing technology. The software was written using the Python 2.7 programming language. The key algorithm of control uses fuzzy logic. The effectiveness of the developed device has been confirmed. The use of the device enabled improvement of the indoor air quality. The presented device may be a solution to improve the indoor air quality by supporting the ventilation system.

scholarly journals The Determination of Indoor Air Quality and Thermal Comfort with Different Space and Ventilation in the Teracce and Bungalow Houses

2021 ◽  
Vol 16 (3) ◽  
pp. 774-793
Author(s):  
Nur Baitul Izati Rasli ◽  
Nor Azam Ramli ◽  
Mohd Rodzi Ismail
Keyword(s):  
Air Quality ◽  
Thermal Comfort ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Physical Parameters ◽  
Air Contaminants ◽  
Code Of Practice ◽  
Air Movement

This study observed the influence of different ventilation, indoor and outdoor activities (i.e., cooking, praying, sweeping, gathering, and exhaust from motorcycle) between a bungalow house (i.e., stack and cross ventilation applications) and a terrace house (i.e., one-sided ventilation application). We appraised the indoor air quality (IAQ) and thermal comfort. We monitored the indoor air contaminants (i.e., TVOC, CO, CH2O, PM10, O3, and CO2) and specific physical parameters (i.e., T, RH, and AS) for four days in the morning (i.e., 6.00 a.m. – 9.00 a.m.), morning-evening (i.e., 11.00 a.m. – 2.00 p.m.), and evening-night (i.e., 5.00 p.m. – 8.00 p.m.) sessions. The results found that cooking activities are the major activities that contributed to the increase of the TVOC, CO, PM10, O3, and CO2 concentrations in the bungalow and terrace houses. However, IAQ exceeded the Industry Code of Practice on IAQ (ICOP) limit in the terrace house. The bungalow house applies stack and cross ventilation, double area, and a long pathway of indoor air contaminants movements. Besides that, the results indicated that cooking activities worsen the ventilation system because CO2 exceeded the ICOP limit on Day 2 at 74.1 % (evening-night session) and Day 3 at 13.2 % (morning session), 11% (morning-evening session), and 50.1 % (evening-night session). Moreover, the combination of mechanical (i.e., opened all fans) and natural ventilation (i.e., opened all doors, windows, and fans) is the best application in the house without a cooking ventilator with lower indoor air movement. Furthermore, the temperatures exceeding the ICOP limit of 23-26 °C for both bungalow and terrace houses could be lower indoor air movement, which is less than the ICOP limit of 0.15-0.5 m/s and high outdoor air temperature. Therefore, it is prudent to have an efficient ventilation system for acceptable indoor air quality and thermal comfort in the family house.

scholarly journals Energy Efficiency – Indoor Air Quality Dilemma in Educational Buildings

2020 ◽  
Author(s):  
◽  
Līva Asere
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Air Quality ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Gas Emissions ◽  
Educational Buildings ◽  
Ventilation Systems

The largest energy consumer in Europe is the building sector, which uses about 40 % of total energy consumption and generates around 36 % of total CO2 emissions in the EU [1], [2]. Rising trends in energy consumption can be observed globally due to the demand of citizens for increased comfort, wider use of electrical equipment as well as other reasons. As energy consumption increases, climate change is promoted. In a number of areas energy could be used more efficiently, minimizing its consumption and, thus, resulting in a reduction of greenhouse gas emissions. To achieve carbon neutrality in 2050 in Europe Union, ambitious targets have been set, such as improving energy efficiency by 41 %, using 100 % of renewable energy sources and reducing greenhouse gas emissions of 80 % to 100 % [1], [3], [4]. Energy efficient buildings help to reduce heat consumption. State and local authorities need to set an example by improving the energy efficiency of their own buildings in order to encourage changes in other buildings as well. Moreover, the introduction of energy efficiency measures in buildings owned by the public sector contributes to the objectives of national climate policy. However, increasing energy efficiency has resulted in buildings becoming more airtight and natural ventilation systems need to be replaced by mechanical ventilation. However, this, in turn, leads to additional energy consumption costs. To avoid cost increases, building managers do not operate or operate unsatisfactory ventilation systems creating unfavourable indoor air quality. This creates a dilemma of energy efficiency and indoor air quality, which reduces performance of building occupants. This dilemma reduces pupils’ performance in educational buildings, reducing their chances of obtaining a good education and in the future working with higher added value which in turn reduces the country’s gross domestic product. The objective of the Thesis is to perform an assessment on energy efficiency – indoor air quality dilemma in educational buildings, its impact analyses on national prosperity, and to propose a solution to the prevention of the dilemma. The Thesis is based on six thematic joint scientific publications. The thesis consists of an introduction and three chapters. Four hypotheses have been formulated in the work that are further studied by various research methods, including system dynamic modelling, measurements in real sites and cost-benefit analysis. The thesis begins with an introduction continuing with a literature review of the topics. Chapter 2 presents the study methods. Chapter 3 examines the results obtained during the study and at the end of the Thesis, the findings are summarised according to the hypotheses.

scholarly journals A Graphical Tool to Estimate the Air Change Efficiency in Rooms with Heat Recovery Systems

2020 ◽  
Vol 12 (3) ◽  
pp. 1031
Author(s):  
Alberto Meiss ◽  
Miguel Ángel Padilla-Marcos ◽  
Irene Poza-Casado ◽  
Antonio Álvaro-Tordesillas
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Heat Recovery ◽  
High Efficiency ◽  
Reference Value ◽  
Reliable Estimate ◽  
Air Supply ◽  
Graphical Tool ◽  
Perfect Mixing

Indoor air quality in buildings must be guaranteed for the health and comfort of the occupants. In order to assess the ventilation strategy of a considered room, the parameter of the air change efficiency ( ε a ) can be used. The objective of this work is to provide designers with a graphical tool for a reliable estimate of the value of ε a of a room. The temperature gradient between the outdoor air supply and the indoor air is so low that the ventilation flow can be assumed as isothermal when high-efficiency heat recovery systems are used. By means of charts, the optimal location of the openings for a better ε a can be determined during the design process, in order to subsequently apply them. It is concluded that it is very important to consider the ε a in the case of openings located in facing walls given that its range varies between 40% and 65%. In contrast, its use can be obviated in the case of openings located in non-facing walls, as the value of ε a obtained is close to 50%; this means a perfect mixing air flow pattern, which is the reference value for the estimation of the indoor air quality (IAQ) in the different national regulations.

scholarly journals Towards a Real-Time Predictive Management Approach of Indoor Air Quality in Energy-Efficient Buildings

Energies ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 3246
Author(s):  
Anass Berouine ◽  
Radouane Ouladsine ◽  
Mohamed Bakhouya ◽  
Mohamed Essaaidi
Keyword(s):  
Energy Consumption ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Predictive Control ◽  
Indoor Air ◽  
Moving Average ◽  
Ventilation System ◽  
Management Approach ◽  
Energy Efficient Buildings ◽  
Air Conditioning Systems

Ventilation, heating and air conditioning systems are the main energy consumers in building sector. Improving the energy consumption of these systems, while satisfying the occupants’ comfort, is the major concern of control and automation designers and researchers. Model predictive control (MPC) methods have been widely studied in order to reduce the energy usage while enhancing the occupants’ comfort. In this paper, a generalized predictive control (GPC) algorithm based on controlled auto-regressive integrated moving average is investigated for standalone ventilation systems’ control. A building’s ventilation system is first modeled together with the GPC and MPC controllers. Simulations have been conducted for validation purposes and are structured into two main parts. In the first part, we compare the MPC with two traditional controllers, while the second part is dedicated to the comparison of the MPC against the GPC controller. Simulation results show the effectiveness of the GPC in reducing the energy consumption by about 4.34% while providing significant indoor air quality improvement.

scholarly journals Indoor air quality in natural-ventilated bedrooms in renovated Norwegian houses

2021 ◽  
Vol 246 ◽  
pp. 01001
Author(s):  
Vegard Heide ◽  
Silje Skyttern ◽  
Laurent Georges
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Indoor Environment ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Opening Angle ◽  
Single Family ◽  
Night Time ◽  
Window Opening

The objective of this work is to investigate the indoor environment in bedrooms ventilated by window opening during night-time. How window opening behaviour affects indoor air quality (IAQ), and how window opening behaviour and IAQ is influenced by external factors, are important questions. The context is renovation of detached wooden houses in Norway. To motivate building owners to renovate their ventilation system, it is important to know the typical indoor environment in bedrooms of existing buildings with natural ventilation. Ten bedrooms in six case houses were investigated by measuring temperature, relative humidity, CO2, particulate matter, formaldehyde and TVOC. The window opening angle was also logged with an accelerometer. The measurements were conducted over 2 to 3 weeks, during March and April. The dwellings were renovated single-family and terraced houses from 1950 – 80, in Trondheim. All the bedrooms had natural ventilation, and the occupants stated they used to open bedroom windows at night. Participants answered a questionnaire about motivations and habits regarding window opening. The most common reason given for not opening was low outdoor temperatures. The window opening behaviour was both predictable and continuous. Windows were open every night in most of the bedrooms, and most of the windows were opened to the same position every night. High CO2 levels during night were found in two bedrooms. In the other bedrooms, the CO2 concentration was satisfying during night-time, although higher concentrations were found in some bedrooms during daytime. Finally, indoor temperature measurements confirmed that many occupants prefer a low bedroom temperature.

scholarly journals IAQ Improvement by Smart Ventilation Combined with Geothermal Renewable Energy at nZEB

2021 ◽  
Vol 9 (1) ◽  
pp. 7
Author(s):  
Javier M. Rey-Hernández ◽  
Ana Tejero-González ◽  
Eloy Velasco-Gómez ◽  
Julio F. San José-Alonso ◽  
Francisco J. Rey-Martínez ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Carbon Emissions ◽  
Geothermal Energy ◽  
Ventilation System ◽  
Energy Systems ◽  
Building Sector ◽  
Zero Carbon

The building sector has the responsibility of being a generator of high carbon emissions, due to inefficient energy consumption in the last decades. For the European Union (EU) and the building sector, this pollution has generated a great impact and concern, establishing objectives in sustainability and energy efficiency in the short term. The EU, committed to energy sustainability, has established several guidelines, aiming at reducing carbon emissions. For this reason, European directives have been published to increase energy efficiency and sustainability in buildings, with EPBD 2018/844/EU being the most up-to-date regulation. This directive mainly focuses on reducing carbon emissions and increasing the efficiency of energy systems in buildings, but it also refers to the importance of establishing indoor air quality indices and smart management of ventilation systems. Before this directive was published, many of the implemented ventilation strategies did not consider the indoor air quality (IAQ) in their scope of established comfort parameters. Therefore, this study analyses the performance of the ventilation system, controlled smartly to cover the demand and the established IAQ rates via CO2 ppm, through renewable geothermal energy systems. This study has been carried out at the LUCIA building, a near Zero Energy Building (nZEB), which belongs to the University of Valladolid, Spain. This building stands out for being one of the most sustainable buildings in the world, according to LEED certification, ranking as the most sustainable building in the northern hemisphere. This building to study is equipped with cutting-edge energy systems, with zero carbon emissions. Several parameters have been analysed (air speed, enthalpy, air flow, temperature, humidity, kWh, climate data, etc.) enabling an energy optimisation of the combined systems. All the monitoring data obtained by the smart management have been analysed, providing favourable outcomes, due to the establishment of IAQ levels, according to the EPBD 2018/844/EU. After this study, the smart management of ventilation combined with removable geothermal energy can be exported as a strategy to reach the established IAQ levels through zero carbon systems.

The effect of vent inlet aspect ratio and its location on ventilation efficiency

2019 ◽  
Vol 29 (2) ◽  
pp. 180-195 ◽  
Author(s):  
Tingsen Chen ◽  
Zhuangbo Feng ◽  
Shi-Jie Cao
Keyword(s):  
Energy Consumption ◽  
Air Quality ◽  
Aspect Ratio ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Ventilation System ◽  
Design Standards ◽  
Total Energy Consumption ◽  
Aspect Ratios ◽  
Ventilation Efficiency

The total energy consumption of buildings in China has been increasing year by year, ventilation energy consumption accounts for more than 20% of the total building energy consumption. The optimisation of ventilation system design aiming at energy conservation is of great significance while keeping healthy indoor air quality. However, the current codes and standards are still lacking specification requirements for vents design, e.g. inlet size ratio or position, which can greatly impact on indoor airflow and ventilation efficiency. In this work, we investigated the aspect ratios of vent inlets and their locations on indoor air quality. Both experimental and numerical simulation methods were adopted. Ventilation efficiency is represented with the local average peak concentration 〈C ̅*〉A,max. Results showed that when vent inlet is in symmetric conditions (i.e. located in the middle of the sidewall) and the aspect ratio between the length and width of the vent inlet equals to 4, ventilation removal efficiency showed the best performance. These findings are of great importance to the engineering applicability and able to provide reference for future design standards.

scholarly journals Indoor air quality in a preschool

2014 ◽  
Vol 13 (4) ◽  
pp. 007-013
Author(s):  
Dorota Koruba ◽  
Ewa Zender Świercz ◽  
Jerzy Piotrowski ◽  
Łukasz Orman ◽  
Marek Telejko
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Poor Quality ◽  
The Poor ◽  
Air Stream ◽  
Standard Solution

The article demonstrates the results of research on the indoor air quality (IAQ) in one of chosen preschools. In such facilities, the standard solution is a system of natural ventilation. Only a small percentage of such buildings is equipped with a mechanical ventilation system with adjustable parameters of the microclimate. The article presents the results of indoor air quality in the local preschool located in Kielce. In the present facility natural ventilation system was used. Preliminary studies confirmed the poor quality of indoor air in a subjected building. During the study, two improvements aimed at improving air quality were proposed. The first improvement was to increase the supply air stream. The second one concerned the installation of equipment for the treatment of indoor air. The results indicate that under certain guidelines it is possible to improve indoor air quality. As an indicator of indoor air quality, concentration of carbon dioxide was adopted. In addition, microbiological tests were performed indoors.

Sign in / Sign up

Export Citation Format

Share Document