Life cycle assessment and energy performance evaluation of a certified sustainable building in a university campus: a case study in Mexico

The construction sector is one of the major bases of economic activity worldwide and drives especially urban development. However, this activity implies diverse environmental impacts throughout its life cycle in terms of pollution, water consumption, eutrophication, energy demand, and resource depletion. Sustainable construction has emerged as an alternative to mitigate the impacts generated by this sector. The sustainable perspective includes from the early stages of planning and design to the demolition of the building. At present, Mexico confronts the challenge of accelerating the adoption of sustainable construction at the national and local scale. This challenge can be supported by evaluating the environmental impacts, establishing concrete goals and implementation of sustainable construction, and developing public policies for planning and incentivizing. To address this challenge, this research project presents a Life Cycle Assessment (LCA) intending, in order to examine the role of building materials, construction, operation, and waste management practices in Mexico. The LCA conducted in this study, evaluated the environmental impacts associated with these processes, with a specific focus on analyzing the energy performance of a Leadership in Energy and Environmental Design (LEED) certified building under different climate change scenarios. The methodology carried out in this project consisted of: (i) conducting a literature review of LCA in buildings; (ii) selecting a LEED-certified building as a case study; (iii) collecting data about materials, structure characteristics, energy and water consumption, construction processes, decommissioning, and waste management; (iv) energy performance evaluation employing a modeling tool to simulate the building and its energy consumption under Future climate; and (v) carrying out LCA based on a cradle-to-grave approach; vi) LCA sensitivity analysis of possible future consumptions due an increase global temperature. The methodology was applied to a case study of the Library building of Tecnologico de Monterrey Mexico City Campus. Among the main findings, highlighted the identification of the building use stage as the stage that generates the most environmental impacts, contributing about 61% due to the energy mix of electricity from the national grid. Additionally, the building materials from the production stage contributed with 32% of the impacts. The study revealed that by increasing the supply of energy from renewable sources to 100%, emissions can be reduced by 50%. While the utilization of building materials that declares environmental impacts during the production can reduce emissions by 16.4%. At the same time, the sensitivity analysis demonstrated that the increase in global temperature leads to an increase in building energy demand, which ultimately increases the environmental impact. The assessment of the environmental impacts of buildings, considering future climate conditions in crucial to contribute to the sustainable development of the country in the long term.