Analyses of Social Housing of the County of Cascais Towards Decarbonization ^†

The construction industry consumes 40% of global energy and is a major target for new environmental sustainability policies. Its high energy use, production processes, and dependence on electrical and thermal energy make it a significant contributor to decarbonization. Social or municipal housing serves to address the need for (re)locating underprivileged families and is often constructed with a primary focus on cost control, compromising the quality of the materials used in the construction and sometimes the comfort and durability of the dwelling. Consequently, these buildings rapidly become dependent on energy for heating or cooling the dwelling, which can increase the energy consumption associated with the resident’s well-being, leading to greater energy dependence and a potential increase in greenhouse gas emissions.

As social housing constitutes public housing, it presents greater opportunities for intervention and implementation measures that align with new policies focused on reducing non-renewable energy consumption and decarbonization.

This research focuses on analyzing the energy consumption of social housing buildings based on their actual annual electricity bills over the past four years, with a case study of the “Fim do Mundo” social dwelling, developed in the 1990 in Cascais, Portugal. With an average energy consumption of 2550 kWh per year per housing unit, and a total of approximately 1158 municipal social housings, the estimated greenhouse gas emissions of social housing in the county of Cascais is approximately 384.137 kg CO₂e per year.

The study explores various approaches aimed at a systematic and multidisciplinary evaluation of implemented passive design strategies and the integration of renewable energy solutions. It identifies the combination of a residential solar panel (400 W) and a wind turbine (1 kW) per housing unit as the most effective strategy, given the existing climate conditions and the energy demands.

The results highlight the importance of incorporating passive design measures in architectural planning. Implementing renewable energy solutions, such as solar panels and wind turbines, proves to be an effective strategy for making social housing buildings energy self-sufficient without the production of greenhouse gases.