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Ground-coupled heat pumps are increasingly being utilized to heat and cool buildings. Although it is difficult to size and to predict their behavior and performance, their design can be optimized via simulations. EnergyPlus is a popular energy simulation program for modeling building heating and other energy flows and, since it is organized to consider borehole heat exchangers via the well-known g-functions approach, it can be used advantageously for that purpose. The Capacity Resistance Model is another recent numerical simulation tool devoted to ground and borehole heat exchangers. In this work, two methods to calculate the g-fucntions were analyzed, using as case-study a real office building, whose imbalance between the heat extracted and injected into the ground was found to be appreciable. The energy imbalance involves a ground temperature drift affecting the system efficiency. The results of the EnergyPlus g-functions and the Capacity Resistance Model model approaches were compared. The capacity of the two methodologies to accurately simulate this phenomenon were analysed also with reference to the available building's long-term monitoring data. The analysis showed the importance of using g-functions suitable to reflect the layout of the borehole field, in order to correctly evaluate the energy performance of the entire ground source heat pump system. [ABSTRACT FROM AUTHOR]

This study evaluates the indoor environmental conditions and children’s comfort levels in 8 classrooms in three Italian primary schools. It is a development of a pilot study previously carried out by the authors in other educational buildings. Spot and long-term measurements were made to evaluate microclimatic conditions (i.e. air temperature, relative humidity, CO2 concentration, and illuminance). A questionnaire, distributed three times, investigated the students’ perception of thermal and lighting comfort, their satisfaction with building-related factors, and their interactions with the environment. Predicted mean vote and predicted percentage dissatisfied indexes were calculated and an adaptive approach was also applied, but their results did not correspond to the students’ subjective evaluation of thermal comfort. An innovative multivariate ranking method was developed as a possible tool to assess building stocks in order to establish priorities for repair, maintenance, and refurbishment. The problem which the students complained about the most was the thermal comfort in the hot season and solar penetration. Moreover, the school with the worst microclimatic conditions was also judged the worst for building-related and psychological factors. [ABSTRACT FROM AUTHOR]

This article deals with the problem of classifying and ranking several multivariate populations of interests using the permutation and combination approach providing also an inferential validity of the procedure. The need to define an appropriate classification of populations, i.e., products, services, teaching courses, degree programs, and so on, is very common within many areas of applied research. Many times the populations of interest are multivariate in nature meaning that many aspects of that populations can be simultaneously observed on the same unit/subject. From a statistical point of view, when the response variable of interest is multivariate in nature, the problem may become quite difficult to cope with especially in case of ordered categorical responses, due to the large dimensionality of the parametric space. Nonparametric inference based on the NPC methodology however, allows us to overcome these limitations, without the need of referring to assume any specified random distribution. [ABSTRACT FROM PUBLISHER]

Ground coupled heat pumps are a notoriously efficient system for heating and cooling buildings. Sometimes the characteristics of the building and the user's needs are such that the amount of heat extracted from the ground during the winter season can be considerably different from the amount injected in summer. This situation can cause a progressive cooling or heating of the ground with a negative effect on the energy efficiency and correct operation of the system. In these cases, an accurate sizing has to be done. In systems already built, it could be necessary to intervene a posteriori to remedy an excessive ground thermal drift due to the energy unbalance. In this work, such a situation relating to a real office building in Italy is investigated and several solutions are examined, one of which has been then implemented. In particular, a hybrid heat pump using as heat sink both the ground and external air is compared with common solutions through computer simulations using a dedicated numerical model, which has also been compared with monitoring data. As a result, the hybrid heat pump shows better performance and limits the thermal drift of the ground temperature. [ABSTRACT FROM AUTHOR]