- Dr Tablada began his architectural education at ISPJAE in his native Cuba, where he attained a Bachelor in Architectu... moreDr Tablada began his architectural education at ISPJAE in his native Cuba, where he attained a Bachelor in Architecture. He continued his studies at the Katholieke Universiteit Leuven in Belgium where he graduated with Magna Cum Laude as a Master of Architecture in Human Settlements and also completed his Engineering Doctorate in 2006. Dr Tablada also holds a Master of Architecture and Conservation from the National Center for Conservation, Restoration and Museology (CENCREM) in Havana. He played a key role for over 16 years in the Historian Office of Havana as a planner and researcher where he focused on the restoration of buildings as well as on research related to natural ventilation and thermal comfort in courtyard buildings. He joined the National University of Singapore in 2011 where together with a group of colleagues founded the NUS-CDL Tropical Technologies Lab. At present he is leading a research project on the integration of solar energy and farming systems in productive facades.edit
A transition to a solar-based carbon neutral economy is crucial to reduce the overall ecological footprint and greenhouse gas (GHG) emissions while providing new housing for the growing urban population worldwide. One of the key measures... more
A transition to a solar-based carbon neutral economy is crucial to reduce the overall ecological footprint and greenhouse gas (GHG) emissions while providing new housing for the growing urban population worldwide. One of the key measures to achieve such reductions as a way to mitigate and adapt to climate change is to increase food and energy self-sufficiency in residential areas. The objective of this study is to explore the potential self-sufficiency in terms of food and energy in generic residential districts in Singapore and Southeast Asia. Computational tools are employed to obtain quantifiable indicators based on sunlight availability. A series of building typologies and urban forms was created as abstractions from actual residential developments in Singapore (1.3°N). In total, 57 cases were assessed in terms of sunlight availability and the impact of three density and geometry parameters: plot ratio, site coverage and building height were considered. Results from selected cases were compared to Hanoi's conditions (21°N). The results show that the indicators having the higher impact on the food and energy self-sufficiency are plot ratio and building height. The cases with the lowest plot ratio (PR < 1.9) achieved food self-sufficiency when a hybrid higher-yield farming method was applied. Regarding energy harvesting, the cases with the lowest building height (<42 m) achieve energy self-sufficiency due to the maximum exposed area with PV per number of residents. In low-latitude regions, solar access is more evenly distributed among all facade orientations than in higher latitudes, therefore providing all facade orientations with food and energy harvesting potential. Food and energy self-sufficiency in equatorial regions is more heavily influenced by the available farming and PV area in relation to the total population than by the reduction of sunlight availability due to building typology and morphology.
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Singapore has committed to reduce greenhouse gases emissions as part of the Paris Agreement. Increasing energy and food self-sufficiency through integration of solar and vertical farming systems into buildings' envelope could play a... more
Singapore has committed to reduce greenhouse gases emissions as part of the Paris Agreement. Increasing energy and food self-sufficiency through integration of solar and vertical farming systems into buildings' envelope could play a significant role in achieving Singapore's targeted reductions. This paper focuses on the design optimization of the façade systems that are to be installed at the Tropical Technologies Laboratory at the National University of Singapore. In particular, the paper presents the results related to five performance indicators which include solar energy and farming potential as well as the impact of the façade design on the indoor daylight conditions, shading and thermal performance. The multi-criteria decision analysis (MCDA) method VIKOR was adopted in the evaluation of the created design alternatives. The results from the computational simulations on radiation, daylight, and thermal conditions were used as inputs. Final optimal façade design is selected for four types of facades according to BIPV and farming systems arrangements for north and south orientations.
Research Interests:
A transition to a solar-based carbon neutral economy is crucial to reduce the overall ecological footprint and greenhouse gas (GHG) emissions while providing dwellings for the growing urban population worldwide. One of the key measures to... more
A transition to a solar-based carbon neutral economy is crucial to reduce the overall ecological footprint and greenhouse gas (GHG) emissions while providing dwellings for the growing urban population worldwide. One of the key measures to achieve such reductions as a way to mitigate and adapt to climate change is to increase food and energy self-sufficiency in residential areas. The objective of this study is to explore the potential self-sufficiency in terms of food and energy in generic residential districts in Singapore and Southeast Asia. Computational tools are employed to obtain quantifiable indicators based on sunlight availability. A series of building typologies and urban forms was created as abstractions from actual residential developments in Singapore (1.3°N). In total, 57 cases were assessed in terms of sunlight availability and the impact of three density and geometry parameters: plot ratio, site coverage and building height were considered. Results from selected cases were compared to Hanoi's conditions (21°N). The results show that the indicators having the higher impact on the food and energy self-sufficiency are plot ratio and building height. The cases with the lowest plot ratio (PR <1.9) achieved food self-sufficiency when a hybrid higher-yield farming method was applied. Regarding energy harvesting, the cases with the lowest building height (< 42 m) achieve energy self-sufficiency due to the maximum exposed area with PV per number of residents. In low-latitude regions, solar access is more evenly distributed among all facade orientations than in higher latitudes, therefore providing all facade orientations with food and energy harvesting potential. Food and energy self-sufficiency in equatorial regions is more heavily influenced by the available farming and PV area in relation to the total population than by the reduction of sunlight availability due to building typology and morphology.
Solar Energy Volume 139, 1 December 2016, Pages 757-769
https://doi.org/10.1016/j.solener.2016.10.041
Solar Energy Volume 139, 1 December 2016, Pages 757-769
https://doi.org/10.1016/j.solener.2016.10.041
Research Interests:
Research Interests:
This paper describes how the wealth of information stored in a Test Reference Year can be visualised making use of a set of macros in Excel. The aim is to make users aware of the fact that the same daily, monthly, and yearly average... more
This paper describes how the wealth of information stored in a Test Reference Year can be visualised making use of a set of macros in Excel. The aim is to make users aware of the fact that the same daily, monthly, and yearly average values can hide a wide variety of realities. Visualised aspects are temperature, relative humidity and the combination of both, wind direction and speed, a comfort indicator for tropical climates based on the three previous parameters, solar irradiation on a horizontal plane and on sloped planes with different orientations. Solar radiation is analysed as well in an open environment as with standardised or specific vertical obstructions. For the analysis of irradiation EnergyPlus is used. Havana (Cuba) is used as an illustration.
In this contribution a previously developed indicator, based on the "Test Reference Year", for the yearly discomfort experienced in tropical climates, is further elaborated. The effect of different "wind speed modification... more
In this contribution a previously developed indicator, based on the "Test Reference Year", for the yearly discomfort experienced in tropical climates, is further elaborated. The effect of different "wind speed modification profiles" on this dis-comfort indicator is analysed. "Wind speed modification profiles" are defined as a factor for each direction (in steps of 10° as in the TRY) that expresses the reduction or the amplification of the wind speed from that direction. In a last step synthetic overview charts are generated visualising how the total yearly discomfort by overheating is changing if the orientation of the "wind speed modification profile" changes. This approach allows to evaluate how effective passive means for cooling by ventilation can be in a given context and what is the most appropriate direction for openings. Havana (Cuba) is used as example.
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The implementation of shading devices is one of the passive strategies to improve indoor thermal conditions during summer. They can obstruct direct solar radiation while permitting wind flow inside the building. Therefore, its use implies... more
The implementation of shading devices is one of the passive strategies to improve indoor thermal conditions during summer. They can obstruct direct solar radiation while permitting wind flow inside the building. Therefore, its use implies two passive interventions for indoor thermal comfort: solar protection and natural ventilation. This study focuses on the implementation of exterior louver systems and the simulation, evaluation and improvement of indoor thermal comfort in an existing modern residential building in Palermo, Sicily. The implementation of the louver systems, the natural ventilation strategies and the evaluation and quantification of the (dis)comfort is performed by coupling Computational Fluid Dynamics (CFD) and Building Energy Simulation (BES) calculations. Values of indoor air speed and pressure coefficients are obtained from CFD calculations and further used as input in BES calculations and comfort analysis. The results show, for this particular case, that overhea...
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Research Interests:
ABSTRACT In this paper a ray-tracing method is developed to describe the global solar transmittance of louver shading devices. The method is integrated in the dynamic building energy simulation program TRNSYS to assess the cooling demand... more
ABSTRACT In this paper a ray-tracing method is developed to describe the global solar transmittance of louver shading devices. The method is integrated in the dynamic building energy simulation program TRNSYS to assess the cooling demand and required peak cooling power in a south oriented office room. The proposed integrated approach allows calculating the solar transmittance for each time step. As the method is quite complex and requires an important computational effort, this research contrasts the results against the performance of simplified modeling and implementation approaches to assess the performance of louver shading devices. The use of view factor models not accounting for reflections in the shading device underestimates the cooling demand and the peak cooling power. It is shown that representing the shading device as a fixed reduction factor, independent of orientation and shading typology is an unacceptable simplification. However, the use of a simplified implementation of shading factors based on ray-tracing calculations is possible within acceptable margins of error. Best results are achieved by implementing solar radiation weighted monthly averages allowing to estimate the cooling demand and peak cooling power within 3%.