Influence of the urban context on solar protection of the vertical envelope and the cooling energy demand of buildings in Cuba

• Published in: Journal of Building Engineering 2023-10, Vol.76, p.107224, Article 107224
• Main Authors: De la Paz Pérez, Guillermo Antonio, Couret, Dania González, Rodríguez-Algeciras, José Abel, De la Paz Vento, Guillermo
• Format: Article
• Language: English
• Subjects: Building energy demand; EnergyPlus program; Solar protection; Urban built context; Vertical building envelope; Warm-humid climate
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2023.107224

Due to global climate change, new approaches are needed to address energy efficiency in buildings and long-term decarbonization. Solar protection of the vertical envelope of buildings is crucial to achieve this goal by reducing the cooling energy demand. However, the Cuban standard for energy efficiency in buildings (NC220-1, 2009) does not establish solar protection requirements based on the orientation of the exterior walls. The study modelled a generic modular space into a building within Energy Plus. The building was located in three geometric urban scenarios (compact, semi-compact and open) with East, Southeast, South, Southwest, and West orientations. In addition, the exposed vertical envelopes of the space were also studied for the North, Northeast and Northwest orientations in the compact context, as it has the greatest influence on sun protection. The study demonstrated that taking into account the influence of the urban built context and the orientation of the building envelope can reduce the cost of solar protection and cooling demand of buildings. The cost-benefit analysis revealed that the payback period of the sun protection elements can be less than 20 months in 7 of the 8 vertical envelope orientations studied. Furthermore, it does not exceed 15 months in the five least favourable orientations (East, Southeast, South, Southwest, and West). The recommendations provided are pioneers in the field of building energy efficiency in Cuba and should be integrated with architectural and urban guidelines in the short term to achieve an effective impact on the economy and for human well-being. •The Cuban standard for energy efficiency does not establish solar protection requirements.•Urban context and window orientation reduce solar protection cost and cooling demand.•The cooling energy demand can be reduced by 56 kWh/y/m2.•The cost of sun protection can be reduced between 24% and 75%.•The return-on-investment period for solar protection elements is less than 20 months.