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 degrees 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 degrees 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. (C) 2016 Elsevier Ltd. All rights reserved.
Tablada, A; Zhao, X
Sunlight availability and potential food and energy self-sufficiency in tropical generic residential districts
Solar Energy