Passive Climate Control Research Articles

The showcase of salt rocks from Cardona in the Barcelona Natural Sciences Museum: conservation and adaptation for passive climate control

The results of the conservation work carried out on an exhibition set-up dating from the early twentieth century are presented. The exhibition set-up consists of a wooden showcase containing about twenty evaporite rocks from the collection of the Museu de Ciències Naturals de Barcelona (Spain). The work involved the remedial conservation of the rock specimens and showcase, and the improvement of the original environmental control system using sustainability criteria. An interdisciplinary team worked on the different phases of the project, which included prior historical and environmental studies. The remedial conservation of all elements in the collection has improved its accessibility and the monitoring of the environmental conditions of the new installation has confirmed the efficiency of the proposed passive environmental control system.

Energy performance of green façades

Green façades consist of the application of vegetation on buildings' vertical enve-lope. The integration of vegetation into the building fabric improves not only the aesthetic appearance, but also the energy performance of the building itself. The introduction of green façades mainly aims at a passive thermal control of build-ings' for enhancing sustainability of the built environment. An experimental green façade was tested at the University of Bari, in a Mediterranean climate context. The experimental green façade was south-exposed and realized with evergreen plants, following the characteristics of the indirect typology. A portion of the south wall was left bare to be used as a control for comparison. The contribution of the green façade in terms of passive climate control was particularly relevant during summer. Vegetation affects the boundary climatic conditions and the surface temperature. A reduction in sensible air and surface temperature of up to 2.2°C and 6.7°C, respectively, was recorded. The wall behind vegetation received 95.6% less solar radiative energy than the bare wall. These results were a direct conse-quence of the two main cooling mechanisms that characterize the green façade, the evapotranspiration and the shading effect. These effects affected the heat transfer reducing the energy input through the covered wall. The reduction of the incoming heat through the covered wall was read as energy saving, since it inevita-bly affects the building energy demand for cooling. It was found that the green fa-çade allowed a mean daily energy saving of 1.1 MJ m-2 and that 90.9% of this was obtained at daytime. These findings contribute to increasing the knowledge of en-ergy functioning and of the real advantages provided by green façades.

Reducing extreme weather impacts in greenhouses: the effect of a new passive climate control system on nutritional quality of pepper fruits

Environmental conditions affect the quality of the fruits and their organoleptic properties. In low-tech greenhouses, these environmental conditions are frequently not optimal for crops. Therefore, the present study demonstrates the effects of the use of an integrated passive heating and cooling system in a greenhouse located in the Mediterranean area on the quality of pepper fruits. The results indicate that the passive system utilized (i) improved many parameters, such as average weight of fruits, °Brix, glucose and fructose content, and P and K content; (ii) increased the values of b* and hab *; and (iii) reduced total phenolic compounds, total amino acids content, and Fe and Zn content. However, the degree of the effect of the climatic factors on these parameters was also affected by harvest time. This novel study highlights the possibility of improving the nutritional quality of pepper fruits by modifying the environmental conditions through the use of passive heating and cooling systems at the same time as reducing the carbon footprint. © 2021 Society of Chemical Industry.

Research on the Microclimate of Protected Agriculture Structures Using Numerical Simulation Tools: A Technical and Bibliometric Analysis as a Contribution to the Sustainability of Under-Cover Cropping in Tropical and Subtropical Countries

The use of protected agriculture structures in tropical and subtropical countries is the main alternative for intensification of agricultural production selected by producers. In general, in these regions, passive and plastic-covered structures predominate, with natural ventilation as the only method of climate control. This phenomenon has been widely studied in different types of structures using computational fluid dynamics (CFD) simulation. Therefore, this review aimed to collect and analyze the publications generated in this field of knowledge between 2010 and 2020. The search for information included the main academic databases available on the web and the analysis was carried out using bibliometric techniques, from which it was possible to identify details inherent to the scientific production, such as countries of origin, main authors, journals, and citations. Likewise, a detailed breakdown of the relevant technical information of the three phases of numerical simulation, such as preprocessing, processing, and postprocessing, was carried out. A compilation of 118 papers published in 65 journals, written by 256 authors, originating from 24 countries was achieved, where it was evident that Mexico and Colombia were the countries with the highest scientific production in the last decade. These papers analyzed, together, a total of 17 different types of structures where polyethylene-covered greenhouses predominated, with steady state simulations, for daytime climate conditions and without the presence of crops. Within the current and future research trends, the predominance of studies analyzing passive climate control methods, new models of insect-proof mesh-house structures, and, finally, studies focused on the structural analysis of greenhouses was found.

Energy Justice in Apartment Buildings and the Spatial Scale of Energy Sustainable Design Regulations in Australia and the UK

Energy vulnerability is a growing concern in many OECD countries post-millennium. An increasing number of residents go without heating or cooling necessities to manage the financial strains of increasing energy costs, low wage growth, and rising housing costs. Housing design quality contributes significantly to a dwelling's energy use and the resident's potential energy vulnerability with good orientation enabling passive climate control or, alternatively, poor design resulting in a reliance on artificial heating, cooling, and lighting for livability. Housing design regulations are accepted as an important tool in planning for achieving energy sustainability and mitigating climate change. However, this article argues for greater recognition and knowledge regarding regulation's ability to protect against energy vulnerability at the residential scale, particularly in the growing number of apartments purchased for the rental market in Australia. By observing the energy sustainability of apartments deemed permissible by Australian and UK regulations, this research demonstrates the significance of building scale in regulations when applied to apartments buildings. An energy justice lens reveals a distinction between measurement at the whole building level and the individual apartment/resident scale in this building typology in particular.

Active Control of Greenhouse Climate Enhances Papaya Growth and Yield at an Affordable Cost

Papaya is a tropical fruit crop that in subtropical regions depends on protected cultivation to fulfill its climate requirements and remain productive. The aim of this work was to compare the profitability of different climate control strategies in greenhouses located in subtropical areas of southeast Spain. To do so, we compared papayas growing in a greenhouse equipped with active climate control (ACC), achieved by cooling and heating systems, versus plants growing in another greenhouse equipped with passive climate control (PCC), consisting of only natural ventilation through zenithal and lateral windows. The results showed that ACC favored papaya plant growth; flowering; fruit set; and, consequently, yields, producing more and heavier fruits at an affordable cost. Climate control strategies did not significantly improve fruit quality, specifically fruit skin color, acidity, and total soluble solids content. In conclusion, in the current context of prices, an active control of temperature and humidity inside the greenhouse could be a more profitable strategy in subtropical regions where open-air cultivation is not feasible.

Thermal barrier effect of green façades: Long-wave infrared radiative energy transfer modelling

Urban green infrastructures contribute to increase sustainability in cities. Among green infrastructures, vertical green systems applied on buildings envelope are promising solutions. Green façades, applied to building walls, allow a sustainable passive climate control in buildings. Energy modelling of green façade systems allows their effective design, simulation and application. Upstream of the modelling there is the mathematical description of the energy transfer that takes place in the system. Radiative heat exchanges in the long-wave infrared range is one of the mechanisms to be considered. This implies the knowledge of geometric configuration factors, surfaces radiometric properties and sky radiation models. This paper focuses on the infrared exchanges occurring on the external surfaces of a green façade, compared with those of a bare wall. A mathematical procedure was followed to define the configuration factor between ground and vertical surface. Nine different sky radiation models were applied to find out, through statistical indices, the best fitting one. The analytical study was supported by empirical data, gathered on an experimental green façade built at the University of Bari. Calculations of the infrared fluxes were made for a summer, an autumn and a winter period, both daytime and night-time. It resulted that the sky model of Walton provided the best agreement with the measured data. In winter, the covered wall showed a reduction of long-wave infrared radiative energy losses equal to 79% compared to the bare wall, so the green façade acted as a thermal barrier.

The influence of sun-protective devices on natural Light distribution in premises

The article observes the new approach to a lighting environment in premises of civil buildings in hot and sunny climatic conditions. Under such conditions, the use of sun-protective devices (SPD) of different types and geometrics becomes traditional way of passive climate control in interiors. However, the authors determined, that the most traditional types of external SPD (such as canopies or awnings) have a different effect on indoor lighting environment due to the conditions of external natural illumination under overcast sky vault or clear sky conditions. In the first case, the stationary SPD act as shadowing elements, which block the light flows from the CIE standard overcast sky. In the second case, which corresponds to a clear sky sunny conditions, such SPD block the solar radiation, decreasing overheating and reflect sun beams to an interior, increasing the value of daylight factor (DF) at least in the furthest from windows areas of a premise. The proposed solutions allow reducing electric power consumption in buildings.

THE USAGE OF GROUND-COUPLED HEAT EXCHANGERS IN SUBTROPICAL CLIMATES

This study aims to identify the feasibility of using a ground-coupled heat exchanger system for air conditioning in subtropical regions. Geothermal systems are used effectively in cold climates, but little explored in hot and humid climate regions, although they show potential for passive air-conditioning environments. The tubes were installed in Southern Brazil, in Foz do Iguaçu, Paraná, which has temperatures of 0ºC in the winter and 40ºC in the summer. The methodology for the research was organized as follows: bibliographic research and geological characterization of the site, system sizing, installation of 22 meters of a 300mm PVC tube, 4 meters depth, and subsequently measurement and data collection on temperatures with use HOBO U10-001 Data Logger. The research was held from March to October 2016. The results showed that at external temperatures of 30ºC, the system was able to cool on average 6ºC, reaching peaks of 7ºC in the temperature of air exit to the environment. At temperatures below 6ºC, the system was able to heat on average 10ºC, with peaks of up to 11ºC. Based on the results, it is concluded that a buried pipe system is a viable alternative for passive climate control in subtropical climates

Developing a method to improve the energy efficiency of modern buildings by using traditional passive concepts of resource efficiency and climate adaptation

Around the world, humans have adapted building forms over the course of centuries to fit external, locally specific parameters such as climate, topography and available building materials. Thus, these structures are generally erected using locally available resources and adapted to fit the regional climate. These concepts were critical in the time before industrialization when neither the building materials, nor the energy and technology necessary for mechanical climate control systems, were available. Even though numerous studies on the concepts of traditional passive climate control exist, the applicability of these concepts in modern buildings is generally not explored. This study addressed this gap in the research by developing a method as a tool to improve the energy efficiency of modern buildings by integrating traditional passive concepts into the planning process. The paper describes an exemplary investigation of traditional residential buildings in the Upper Town of Thessaloniki, which has been the basis for developing the tool. The results of this case study showed that adding traditional concepts to the current legal requirements would improve indoor comfort and thus building energy performance. The tool could also be used for educational purposes to make students of the built environment aware of the great diversity of energy efficient heating, cooling and ventilation methods present in tradi tional buildings. This presents them with the opportunity to practice applying such alternative building designs and make comparisons with the alternatives.

Apartment Prototype with Enhanced Natural Ventilation System for Vietnam

With boundary-less efforts being made to increase the sustainability of human existence, the architecture field has also been making great efforts concerning this global trend. On the other hand, the urban conditions of developing cities require high-density housing solutions to house their rapidly increasing populations. In the case of apartments, the latter takes priority over the former, thus resulting in high-energy consumption for climate control and therefore high utility bills. This conflict is most pronounced in hot and humid tropical climate areas such as Southeast Asia, where passive climate control is virtually impossible to achieve in high-density housing types. In this paper, the authors make an attempt to develop an apartment prototype for Vietnam that 1) reflects the spatial organization of the Vietnamese ″Tube House,″ 2) allows natural ventilation that is absent in the Tube Houses, while 3) maintaining a high level of density. In doing so, the authors applied environmental strategies used in Vietnamese vernacular architecture and tested the performance of the prototype through air current analysis. As a result, the first two goals were achieved, while the third goal was achievable only to a certain extent.

Climate Responsive Traditional Architecture of Chettinadu Housing in Tamilnadu, India- A Qualitative and Quantitative Analysis During Summer

Buildings represent the major energy consuming sector in India. Sustainable and climate responsive architecture offers possible solutions to this high energy demand. Vernacular buildings, in contrast to modern 20th century buildings, are more climate receptive to the environment and are based on principles evolved over many generations. The traditional architecture of housing in Chettinadu, Tamil Nadu, India is known for its use of natural and passive methods for a comfortable indoor environment. However, it has not been proved by a detailed and quantitative evaluation method so far. A summer field study was thus conducted to investigate the indoor environmental conditions in such housing. The objective of the investigation was to understand the solar passive features in Chettinadu housing by qualitative and quantitative analysis of thermal comfort parameters. This was undertaken by continuously monitoring the indoor and outdoor conditions using a custom made instrument called the “Architectural Evaluation System”. The results showed that the natural and passive climate control system of this traditional housing style provides a comfortable indoor environment irrespective of the outdoor climatic conditions.

Reducing energy peak consumption with passive climate control methods

In recent years, European electrical consumption in buildings is experiencing a marked increase, rising to values above design conditions. Consequently, power cuts occur in different periods, such as during the early morning hours in winter and the last hours of occupation in summer. To solve this problem, passive methods could help to reduce energy peaks. Specifically, internal wall coverings were applied to define the moisture-buffering capacity of permeable coverings in indoor air. These permeable coverings improved the indoor partial vapour pressure and, as a result, the ambience acceptability and local thermal comfort, despite the use of an air barrier and less permeable coverings, when compared with other authors. The daily periods in which internal coverings work are clearly defined, and give us an understanding of the peak energy consumption at different times. In particular, peak reductions of 20% and 4% in the energy consumption for indoor air conditioning, respectively during the summer and winter seasons, were obtained with permeable coverings. Permeable coverings have been demonstrated to be an effective solution as a passive control method for indoor air conditions, especially in the summer season and, consequently, are an energy saving technique.

Hourly indoor thermal comfort and air quality acceptance with passive climate control methods

Nowadays, the effect of permeable coverings on conditioning of indoor air in real buildings, has become of special interest in the process of achieving a sustainable built environment. In these studies, the first hour of occupation is usually selected, because it is then that the strong effect of coverings is felt, due to the low ventilation rate that prevails during the unoccupied period. In this context, an hourly study enables us to understand the behaviour during working periods and the effect of coverings on indoor thermal comfort conditions, air quality acceptance and peaks of energy consumption. Results showed that permeable coverings reduce energy consumption and peak loads and this effect is controlled by air renewal. Consequently, during the summer season, indoor thermal comfort and acceptance of indoor air conditions were found to be better with permeable coverings. In winter, in offices with impermeable coverings inadequate operative conditions of heating, ventilation, and air-conditioning (HVAC) induced a slight improvement on indoor air conditions, during the period of occupation. Further studies are required to assess the real effect of building materials and their use, and substitution of the current HVAC systems with this type of passive method. In particular, a suitable method to determine the adequacy of coverings and their active thickness needs to be developed.

Energy saving with passive climate control methods in Spanish office buildings

This work comprises case studies of passive indoor climate control techniques, applied to a number of office buildings in Spain. The main objective of the work was to evaluate the effects of using indoor permeable coverings on energy savings, for the same indoor thermal comfort conditions. Previous studies have shown that permeable coverings will lead to optimal indoor comfort conditions, which depend on maximum and minimum monthly mean outdoor temperature and relative humidity values. This work shows that, both in summer and winter, indoor energy consumption decreases with the permeability of coverings. An energy saving potential of 3 kWh/m 2 per year may be achieved, which leads to the possibility of replacing mechanical HVAC by passive methods in mild climates, such as in Spain and Portugal.

Improving PAQ and comfort conditions in Spanish office buildings with passive climate control

Some researchers have demonstrated that passive moisture transfer between indoor air and hygroscopic structures has the potential to moderate variations of indoor air relative humidity and , thus, to improve comfort and PAQ [Simonson CJ, Salonvaara M, Ojalen T. The effect of structures on indoor humidity-possibility to improve comfort and perceived air quality. Indoor Air 2002; 12: 243–51; Simonson CJ, Salonvaara M, Ojalen T. Improving indoor climate and comfort with wooden structures. Espoo 2001. Technical Research Centre of Finland, VTT Publications 431.200p+app 91p]. The main objective of this study is to show the internal wall coating effect on indoor air conditions and, as a consequence of this, in comfort conditions and PAQ. In a previous paper [Orosa JA, Baaliña A. Passive climate control in Spanish office buildings for long periods of time. Building and Environment 2008], we analysed the influence of permeable and impermeable materials on indoor air conditions , during the unoccupied period , in 25 office buildings in different seasons. Results obtained lead us to conclude that real coverings such as permeable, semi-permeable and impermeable types, present different behavioural patterns in indoor air conditions. Furthermore, we concluded that an absorbent structure will moderate relative humidity indoors. In this paper, we study this indoor relative humidity effect on local thermal discomfort, due to decreased respiratory cooling, and indoor ambience acceptability for the early hours of morning applying PD and Acc models [Toftum J, Jorgensen AS, Fanger PO. Upper limits for indoor air humidity to avoid uncomfortably humid skin. Energy and buildings 1998; 28: 1–13; Toftum J, Jorgensen AS, Fanger PO. Upper limits of air humidity for preventing warm respiratory discomfort. Energy and Buildings 1998; 28: 15–23] such as that proposed by Simonson et al. [The effect of structures on indoor humidity-possibility to improve comfort and perceived air quality. Indoor Air 2002; 12: 243–251]. Results showed that hygroscopic structures have the potential to improve local thermal comfort and especially PAQ in the first hours of occupation and that relative influence of humidity on acceptability was higher than on thermal sensation. These conclusions would, with a more intelligent design, give energy saving and improve comfort and PAQ.

Passive climate control in Spanish office buildings for long periods of time

Recent studies have shown that the effect of the internal wall coating on an indoor thermal environment can be seen for short periods of time [Hameury S. Moisture buffering capacity of heavy timber structures directly exposed to an indoor climate: a numerical study. Building and Environment 2005;40(10):1400–12]. However, for long periods of time this effect is hidden by the air renovation and vapour release. These passive methods are gaining popularity because they are energy conscious and environmentally friendly. However, there is little published data on mass transfer between building envelopes and indoor air [Simonson CJ, Salonvaara MH. Mass transfer between indoor air and a porous building envelope: part I—field measurements. In: Proceedings of healthy buildings, vol. 3, 2000; Simonson CJ, Tuomo O. Moisture performance of buildings envelopes with no plastic vapour retarders in cold climates. In: Proceedings of healthy buildings, vol. 3, 2000]. The main objective of this study is to show the internal wall coating effect on indoor air conditions by means of the indoor air parameters. These measurements were taken in 25 office buildings during different seasons. Our results will allow us to understand the internal coating effect for long and short periods of time and, therefore, the thermal comfort and indoor air quality conditions.

A study of the effectiveness of passive climate control in naturally ventilated residential buildings in Singapore

Singapore has the hot and humid climate throughout the year. Many passive climate control methods are adopted in the naturally ventilated residential buildings to help achieve thermal comfort and reduce the energy consumption of air-conditioning. A field measurement and computational energy simulations were conducted to examine the effectiveness of commonly used passive climate control methods for these buildings. The effect of building orientation, façade construction, special roof system and window shading device on indoor thermal environment and cooling load was studied. The surface temperature of external wall and indoor thermal environment was measured to analyze the façade thermal performance. The cooling load was simulated to evaluate the effectiveness of various passive climate methods. Using the special roof system as thermal buffer is the most efficient method to reduce the room cooling load.

Paintings: the (show) case for passive climate control

Climatic conditions kept as uniform and as constant as possible: these are the prerequisites demanded by restorers and museum technicians when works of art are to be handed out on loan, transported or permanently exhibited. If a work of art is to be placed in an exhibition hall with dubious, unstable or merely unpredictable climatic conditions, a climate-controlled showcase is needed for the more sensitive exhibits. Usually the airconditioning of such showcases is limited to maintaining a certain relative air humidity. The methods for reaching this objective are manifold, and have already been published in detail elsewhere,1 so that we can refrain from listing them again here. A basic distinction has, however, to be drawn between active and passive climate control.

CLIMATE CONTROL IN LIBRARIES AND ARCHIVES

Article that clearly explaines conventional environmental systems used in libraries and museums. More importantly, passive climate control methods including building-within-a-building design, landscaping, protective enclosures for books, and temperature and RH buffering capacity are adressed in in detail.