This paper presents a methodology and instrumentation system for the indirect measurement of the thermal diffusivity of a soil at a given depth from measuring its temperature at that depth. The development has been carried out considering its application to the design and sizing of very low enthalpy geothermal energy (VLEGE) systems, but it can has many other applications, for example in construction, agriculture or biology. The methodology is simple and inexpensive because it can take advantage of the prescriptive geotechnical drilling prior to the construction of a house or building, to take at the same time temperature measurements that will allow get the actual temperature and ground thermal diffusivity to the depth of interest. The methodology and developed system have been tested and used in the design of a VLEGE facility for a chalet with basement at the outskirts of Huelva (a city in the southwest of Spain). Experimental results validate the proposed approach.

Increasing problems regarding pollution and climate change have long been demonstrated by scientific evidence. An important portion of carbon emissions are produced by the building sector. These emissions are directly related not only to the building’s energy consumption, but also other building attributes affecting the construction and operation of existing buildings: materials selection, waste management, transportation, water consumption, and others. To help reduce these emissions, several green building rating system (GBRSs) have appeared during the last years. This has made it difficult for stakeholders to identify which GBRSs could be more suitable to a specific project. The heterogeneity of the GRBS scenario requires the creation of a transparent and robust indicator framework that can be used in any country within the European Union (EU), which is a common EU framework of core sustainability indicators for office and residential buildings Level(s) with the goal to provide a solid structure for building sustainability certification across all countries of the EU. This paper provides a comprehensive review of the most common GBRSs within the EU: Building Research Establishment Assessment Method (BREEAM), Deutsche Gesellschaft für Nachhaltiges Bauen (DGNB), Haute Qualité Environnementale (HQE), and Leadership in Energy & Environmental Design (LEED), and a bottom up comparison of the influence in the final score produced by the indicators stated by Level(s). The indicators studied show a different influence of Level(s) indicators on every GBRS, where LEED and BREEAM were most affected while HQE and DGNB were less so. This paper demonstrates the heterogeneity of current GRBSs in the EU scenario and the difference between sustainability assessments, where DGNB seems to be more aligned to the current EU framework. Finally, the paper concludes with the need to work to achieve alignment between the GBRS and Level(s).

Knowledge of buildings′ energy efficiency has advanced thanks to research carried out in recent years. Many of the discoveries in this field have recently been incorporated into mandatory construction regulations for each country. However, not many of the architects and engineers involved in the construction industry clearly know how to achieve those goals in their designs. This document is based on the extensive experience in architectural design, the integration of renewable energies, the energy simulation of buildings and data acquisition, and analysis of the research team involved. It is presented in a practical and holistic approach and focused in subtropical climates. A structured methodology for the proper decision-making process during all the different stages of a minimum energy building (MEB) is likewise presented. The proposed methodology depicted aims at providing architects and engineers with a systematic and orderly step-by-step procedure and incorporates the instrumentation/control and data analysis as essential elements that support the validation of the expected results from the design, the construction, and the operation phase of the building. The paper develops a case study that illustrates the proposed methodology. This new methodology for MEB in subtropical climates constitutes an innovation in this field.

Today, most countries in the world have mandatory regulations, more or less strict, regarding energy efficiency in buildings. However, a large percentage of the buildings already built were constructed under lax or non-existing regulations in this regard. Therefore, many countries are facing the energy refurbishment of their existing buildings to reduce their carbon footprint. Depending on ambient weather conditions where a building settles, its operation with respect to the achievement of maximum energy efficiency should usually be different. This happens in subtropical climates when, during the year and depending on the season, the building needs to conserve heat, evacuate it or even make an exchange with the outside to take advantage of favorable environmental conditions. This paper presents a complete methodology for conducting building energy efficiency refurbishments in subtropical climates in order to convert them into minimum energy buildings. The proposed methodology is illustrated by a case study in a dwelling that includes all the stages, from the analysis of the existing dwelling to the refurbishment works, showing the final results and the subsequent dwelling operation.

The construction sector is a great contributor to global warming both in new and existing buildings. Minimum energy buildings (MEBs) demand as little energy as possible, with an optimized architectural design, which includes passive solutions. In addition, these buildings consume as low energy as possible introducing efficient facilities. Finally, they produce renewable energy on-site to become zero energy buildings (ZEBs) or even plus zero energy buildings (+ZEB). In this paper, a deep analysis of the energy use and renewable energy production of a social dwelling was carried out based on data measurements. Unfortunately, in residential buildings, most renewable energy production occurs at a different time than energy demand. Furthermore, energy storage batteries for these facilities are expensive and require significant maintenance. The present research proposes a strategy, which involves rescheduling energy demand by changing the habits of the occupants in terms of domestic hot water (DHW) consumption, cooking, and washing. Rescheduling these three electric circuits increases the usability of the renewable energy produced on-site, reducing the misused energy from 52.84% to 25.14%, as well as decreasing electricity costs by 58.46%.