Cool, translucent natural envelope. Thermal-optics characteristics experimental assessment and thermal-energy and day lighting analysis

Innovative construction elements are increasingly studied to improve the energy performance of new and existing buildings, to satisfy global regulations and societal needs. In this view, optimizing buildings energy efficiency and sustainability are crucial aspects, given their high energy saving potential with respect to the other sectors characterizing human activities. Natural materials are often preferred to artificial materials, thanks to their more sustainable production and to the reduced content of harmful substances. In particular, light, thin marbles have been recently analyzed as building envelope elements. Their cooling potential demonstrated how such envelopes have the threefold advantages of reducing solar heat gains into the building, accumulating and releasing less heat, reducing the Urban Heat Island (UHI) effect and consequently mitigating global warming. However, an important feature that has not yet been analyzed in literature and that is considered in this research is light passage throughout the translucent envelope, permitting an additional energy saving due to the contribution to artificial lighting. In this work, this feature of the translucent envelope is considered, by experimentally measuring thin, white marble panels’ optic characteristics and implementing them in a thermal-energy dynamic simulation, to demonstrate the additional advantage of natural daylight to the overall building energy balance

Sustainable energy saving alternatives in small buildings

Day lighting significance in architectural designs is well established for enhancing visual comfort, energy-efficiency and low carbon buildings development. Practising the atrium element in the modern architectures has been increasingly popular in recent years because of the fact that the transitional space with good environmental elements can improve the quality of the buildings and reduce extra energy utilisation. The present study explores the advantages and effectiveness of the atrium on the energy performance of small buildings, a case study of ‘The Azuma Row House’. Based on local micro-climate data Autodesk Ecotect Analysis was performed to calculate the daylight factors and the energy demand of the building. A comparison was made with atrium and without atrium in the building to evaluate overall energy savings. The results show a higher annual heating energy demand with atrium 3443 kWh compared without atrium 2526 kWh. The annual cooling energy demand without atrium 2516 kWh is significantly greater than with atrium 912 kWh. The total energy requirements under no atrium case is about 5042 kWh which is considerably higher than the total annual energy demand with atrium 4355 kWh. The total amount of energy saved is about 15.7% per year by introducing the sunlight through the atrium. Along with the increasing issue of the energy crisis, environmental problem and the beautiful design of atrium, the development of atrium in modern architecture designing is feasible to have a good future

Daylight and Architectural Simulation of the Egebjerg School (Denmark): Sustainable Features of a New Type of Skylight

This article discusses the performance of a new skylight for standard classrooms at the Egebjerg School (Denmark), which was built ca. 1970. This building underwent important reforms under a European project to which the authors contributed. This research aimed to create a new skylight prototype that is useful for several schools in the vicinity, since there is a lack of educational facilities. The former skylights consisted of plastic pyramids that presented serious disadvantages in terms of sustainability matters. During the design process, the priority changed to studying the factors that correlate daylighting with energy and other environmental aspects in a holistic and evocative approach. Accordingly, the new skylight features promote the admittance and di usion of solar energy through adroit guidance systems. In order to simulate di erent scenarios, we employed our own simulation tool, Diana X. This research-oriented software works with the e ects of direct solar energy that are mostly avoided in conventional programs. By virtue of Lambert’s reciprocity theorem, our procedure, which was based on innovative equations of radiative transfer, converts the energy received by di usive surfaces into luminous exitance for all types of architectural elements. Upon completion of the skylights, we recorded onsite measurements, which roughly coincided with the simulation data. Thus, conditions throughout the year improved

Thermal performance of a naturally ventilated building using a combined algorithm of probabilistic occupant behaviour and deterministic heat and mass balance models

This study explores the role of occupant behaviour in relation to natural ventilation and its effects on summer thermal performance of naturally ventillated buildings. We develop a behavioural algorithm (the Yun algorithm) representing probablistic occupant behaviour and implement this within a dynamic energy simulation tool. A core of this algorithm is the use of Markov chain and Monte Carlo methods in order to integrate probablistic window use models into dynamic energy simulation procedures. The comparison between predicted and monitored window use patterns shows good agreement. Performance of the Yn algorithm is demonstrated for active, medium and passive window users and a range of office constructions. Results indicate, for example, that in some cases, the temperature of an office occupied by the active window user in summer is up to 2.6ºC lower than that for the passive window user. A comparison is made with results from an alernative bahavioural algorithm developed by Humphreys [H.B. Rijal, P. Tuohy, M.A. Humphreys, J.F. Nicol, A. Samual, J. Clarke, Using results from field surveys to predict the effect of open windows on thermal comfort and energy use in buildings, Energy and Buildings 39(7)(2007) 823-836.]. In general, the two algorithms lead to similar predictions, but the results suggest that the Yun algorithm better reflects the observed time of day effects on window use (i.e. the increased probability of action on arrival)

Methodologies for self-organising systems:a SPEM approach

We define ’SPEM fragments’ of five methods for developing self-organising multi-agent systems. Self-organising traffic lights controllers provide an application scenario

Amalgamating sustainable design strategies into architectural curricula

In the era of climate change, rising sea levels, the hole in the ozone layer and current food crisis, sustainability is no longer a matter of choice; it is a must. While the term sustainability manages to embed itself in all aspects of contemporary life, sustainability in the built environment requires special attention. Designs created by architects and planners play a fundamental part in shaping the way we live, behave and interact with our surroundings. Smith (2001) argued that instilling sustainable design in curricula at schools of architecture is a significant method of encouraging sustainable architectural design in practice. This is particularly important in non-sustainable societies such as those of the Middle East. For these reasons, this study aims at exploring ‘sustainability strategies,’ as they may be described, adopted in different schools of architecture. The research surveys architectural curricula at different Royal Institute of British Architects (RIBA) exempted schools of Architecture, at part 1 and 2 levels. Meanwhile, it also observes the contradiction and difficulties of teaching sustainable architectural design in Egyptian and Middle Eastern societies, whose cultural fabric does not encourage environmental awareness. Finally, the study attempts to investigate, in an increased level of detail, how sustainable design education fits into the undergraduate and postgraduate curricula of the Architectural Engineering and Environmental Design Department (AEED) at the Arab Academy for Science, Technology and Maritime Transport (AASTMT) in Alexandria, Egypt. The paper concludes that the proper application of sustainable design strategies at early stages of architecture education has developed architects with sturdy understanding of their environment, climate and local identity, which can never happen if this is addressed in postgraduate studies or at later stages of the Architecture career

Exploring the Interplay between CAD and FreeFem++ as an Energy Decision-Making Tool for Architectural Design

The energy modelling software tools commonly used for architectural purposes do not allow a straightforward real-time implementation within the architectural design programs. In addition, the surrounding exterior spaces of the building, including the inner courtyards, hardly present a specific treatment distinguishing these spaces from the general external temperature in the thermal simulations. This is a clear disadvantage when it comes to streamlining the design process in relation to the whole-building energy optimization. In this context, the present study aims to demonstrate the advantages of the FreeFem++ open source program for performing simulations in architectural environments. These simulations include microclimate tests that describe the interactions between a building architecture and its local exterior. The great potential of this mathematical tool can be realized through its complete system integration within CAD (Computer-Aided Design) software such as SketchUp or AutoCAD. In order to establish the suitability of FreeFem++ for the performance of simulations, the most widely employed energy simulation tools able to consider a proposed architectural geometry in a specific environment are compared. On the basis of this analysis, it can be concluded that FreeFem++ is the only program displaying the best features for the thermal performance simulation of these specific outdoor spaces, excluding the currently unavailable easy interaction with architectural drawing programs. The main contribution of this research is, in fact, the enhancement of FreeFem++ usability by proposing a simple intuitive method for the creation of building geometries and their respective meshing (pre-processing). FreeFem++ is also considered a tool for data analysis (post-processing) able to help engineers and architects with building energy-efficiency-related tasks