Mejoras y modificaciones bioclimáticas destinadas al aumento de la eficiencia de una vivienda

Abstract

A big part of the energy consumption is done in the residential sector, and lowering plays a big role on reducing the impact of climate change. This is why, apart from reducing the new buildings consumptions using the latest technologies, it’s also important to improve the efficiency of the older ones. Also, centralised electric generation, on power plants, is outdated and needs to be renewed. This can be possible through renewable energies, using a distributed generation on the consumption points. In this project, the improvement of a building built on year 2000, located in the Pyrenees, was studied. First of all, the current situation had to be analysed so we would know which improvements had to be done. This way, we studied its yearly consumption in electricity and heat. The measures that were studied were the improvement of the thermal envelope and the installation of photovoltaic panels and solar thermal collectors. Its implementation was studied separately to know which measures were viable and which weren’t. The photovoltaic installations would suppose a total saving in energy of 5033 kWh each year, also producing 2144 kWh of surplus energy that would be injected into the grid. It would also be the most profitable of the 3 measures studied, with an initial investment of 11.070 €, producing 1914 € yearly, and with a short time return of 5 years and 10 months, due to the current high prices of the electricity. The improvement on the thermal envelope would suppose a yearly saving of 6.674 kWh in heating. The initial investment would be 26.000 €, but the government would cover a really high percentage of that, thanks to the program PREE 5000. This way, the initial investment would be returned in 8 years and 8 months, thanks to the economical savings in heating. The solar thermal collector installation would be the less impactful one. We designed it to only cover the demand for domestic hot water (DHW), since its generation wasn’t enough to cover the heating demand. First of all, we considered an installation of 70 collectors (designed to cover an average month, April in this case), but the surplus in hot water generated during summer made us realise it was oversized. This way, we studied the installation of half the collectors, 35, which would generate savings for 199 m3 of domestic hot water, which, considering current prices, we valued this as a yearly saving of 498 €. With an installation cost of 21.350 €, the return in time would be of 17 years and 2 months, even with the government covering 60% of it, also due to the PREE 5000 program. As a conclusion, the photovoltaic panels installation is profitable, even more nowadays due to the rising of electricity prices, while the improvement on the thermal envelope is profitable due to the government economic aid. The installation of solar thermal collectors is not recommended, since it has a really low profit compared to the expensive initial investment.