Establishing an Optimal Range of Density for Sustainable Urban For: A Proposal Based on the Reconstruction Process after the 2010 Earthquake in Chile

Abstract

In 2010 Chile suffered a devastating earthquake that requires the rebuilding of more than 100,000 houses including entire neighborhoods. This provides a unique opportunity to plan and build sustainable and resilient cities. The earthquake, it has also made evident the necessity of neighborhoods to prepare for the increasing frequency of natural disasters and adverse consequences of climate change. A recurring theme of discussion for the planning of sustainable cities lies in the level of density for the urban form. So far, making cities more compact has been understood as the best option due to their reduction in energy consumption mainly for transport and residential sectors. However, these sustainable proposals continue to depend largely on fossil fuels. Besides, they give fewer opportunities to produce energy on-site. Now, as oil runs out and the increasing population leads to more global energy consumption, sustainability in terms of urban communities should be understood as the ability to be energy self-sufficient and resilient against the adverse insecurity energy future. This research focuses on finding the best range of density for sustainable urban form from the point of view of self-sufficient and resilient neighborhoods. To achieve this energy self sufficiency and resilience, four parameters have been selected, they are: energy efficiency measures to reduce energy consumption, the use of solar energy (PV and Solar Water Heater) to provide the basic housing's energy needs, electric cars as a method of transport and food production at home. The study has been based on four real neighborhoods in the Chilean city of Talca, with similar economic, social and construction features but different in terms of densities measured by of household per hectare. Determining which case study, with its corresponding density, achieves a balance between its annual energy consumption and on-site energy generation potential, will serve as a base to establish the best range of sustainable density. Although the results obtained reflect a snapshot for the specific situation in Talca, the methodology could be used for any other case under similar conditions, if all data were accessible.