Evaluación ambiental de un proyecto tradicional vs un edificio de consumo casi nulo, analizando cuando la energía de los materiales será más alto que el uso de energía durante la vida

Abstract

This master thesis seeks to propose an optimization of the technical building code and the way buildings are constructed. The main objective is to help reduce the energy use and the CO2 emissions from buildings during its whole lifecycle. This thesis will discuss possible models on how to optimize the design of Nearly Zero Energy Buildings (NZEB) using European and international standards. However, as opposed to the NZEB definition published by the EU, embodied energy and emissions from materials and products will also be taken into account. Emissions from a building can be divided in two categories. Emissions from the materials in the construction phase on one hand, and from operational energy use on the other hand. An important part of the emissions due to materials occur during the construction phase, whereas emissions related to operational energy occur little by little every year during operational years. But it is important to count emissions from materials during the operational years, which will occur when the building is maintained, repaired and refurbished. The frequency of replacing the various components is shown in the last chapter. It is also important to take into account end-of-life and waste handling of substituted products. Whether operational energy or embodied energy in materials contributes most to buildings emissions depends on the choice of materials and products, the choice and availability of energy supply and the energy performance of the building envelope. Local climate conditions and available local energy sources also play a very important part. A shift in focus from operational energy use to lifecycle energy use could help us make better design decisions for our buildings. If the aim is to reduce the overall greenhouse gas emissions and reduce the environmental impact over the lifecycle of a building, one could argue that it could be more efficient to use less and locally produced construction products, rather than having high weight and volume products being transported across the globe. By comparing LCA assessments and calculated energy need over the lifecycle we can optimize building design and hereby reduce the overall greenhouse gas emissions.