Analysis of a double source heat pump system in a historical building

This work presents the case study of the retrofitting of a historical building of the University of Padua, equipped with a hybrid heat pump system, which uses as heat source/sink the ground and ambient air. The building is located in Padua (Italy) and it is a historical complex of the late 1800, previously used as a geriatric hospital, in which a retrofit process is occurring in order to build the new humanistic campus of the Padua University reaching the highest energy efficiency. The refurbishment is in progress and regards both the building envelope and the plant-system. The building is equipped with two types of heat pumps: the first one is coupled to the ground with borehole heat exchangers and the second is a common air-to-water heat pump. The entire building plant system has been investigated through integrated computer simulations making use of EnergyPlus Software. A new control strategy in order to manage the two types of the heat pumps has been developed in order to increase the energy efficiency. The results outline the potential of the computer simulations in order to control the hybrid heat pump system. In fact, a suitable switch temperature was found in order to move from ground to air source/sink for the heat pumps. In addition, this strategy allows the control of the thermal drift of the ground temperature throughout the years

Double source heat pump: A case study

The design of a Ground Source Heat Pump (GSHP) system is critical because design choices affect the system's energy performance and operating conditions. If the thermal load profile on the ground side is unbalanced the ground temperature will change throughout the time and, consequently, also the energy efficiency of the heat pump. This phenomenon is known as "ground thermal drift". A possible solution to avoid this inconvenience is the adoption of a hybrid system.In this work a double source heat pump is investigated, i.e. the heat pump can use air or ground as heat source or heat sink. The case study is an office building located in the city of Padova (Italy). The building load profile is cooling dominant and a thermal drift can be observed in the monitoring records. A new water-to-water heat pump coupled to the boreholes and also to an air-cooled condenser was recently installed in order to tackle the thermal drift of the ground.Detailed computer simulations of the system were carried out via EnergyPlus software to investigate the energy performance of the system and the control strategy for switching between the heat sources (air or ground). The study shows the advantages of the double source heat pump

Trace elements: critical insights from 15 years of monitoring in the Venice Lagoon catchment basin (Italy)

The study focused on selected trace elements (As, Cd, Cr, Hg, Ni, Pb) monitored in surface waters of the Venice Lagoon catchment basin (North East Italy) over the period 2000-2015. The monitoring was undertaken to verify the achievement of the quality objectives set by the European and national legislations. The available results have been analyzed to evaluate the chemical status of water bodies. The limit of quantification (LOQ) of the applied analytic techniques appears critical for the adequate water monitoring; for some parameters, the percentage of not visible values due to non-satisfactory LOQ was higher in the beginning of the period; the subsequent improvement of LOQ allowed assessing the respect of environmental quality standards (EQSs). The study analyzes time trends in single stations and the differences between detected concentrations in the considered stations. Moreover, maximum concentrations and water flows have been considered to understand the potential correlation. Cumulated frequency curves for the most critical parameters have been built to identify situation of potential overtaking of the EQSs in force. The most polluted sampling stations of the drainage basin for the six trace elements were found in Cuori and Fiumazzo rivers. Although LOQs changed over time, the recorded trends show a quality improvement and a good compliance with respect to EQSs set by European legislation, while considering EQSs set by local special legislation, the objectives are not yet satisfied. Arsenic is ubiquitous; thus, it can be supposed to be originated as a background environmental concentration, while nickel appears of industrial origin according to its point and local presence

Climate Change 2007: Impacts, Adaptation and Vulnerability.

Impatti, adattamento e vulnerabilità Le cause e le responsabilità dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilità” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici

Climate Change 2007: Causes, impacts, mitigation.

L’obiettivo di questo articolo è presentare, per quanto possibile in modo organico, semplice e obiettivo il tema del riscaldamento globale. Per la stesura dell’articolo ci si è basati fedelmente sul documento redatto, votato e pubblicato quest’anno dal comitato intergovernativo sui cambiamenti climatici (Intergovernmental Panel on Climate Change, IPCC). Esso rappresenta la sintesi, delle varie ricer- che svolte sul tema, che gode del consenso mondiale più ampio. Ci si è basati su tale documento poiché si desidera fornire ai professionisti dei dati condivisi dai più a livello mondiale, per poterli utilizzare nel loro lavoro e nelle loro argomentazioni. Si desidera inoltre stimolare, in modo costruttivo, l’interesse verso un problema che va a influenzare la nostra vita e quella delle generazioni future

Climate Change 2007: The Physical Science Basis.

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante

Climate Change 2007: Causes, impacts, mitigation.

L’obiettivo di questo articolo è presentare, per quanto possibile in modo organico, semplice e obiettivo il tema del riscaldamento globale. Per la stesura dell’articolo ci si è basati fedelmente sul documento redatto, votato e pubblicato quest’anno dal comitato intergovernativo sui cambiamenti climatici (Intergovernmental Panel on Climate Change, IPCC). Esso rappresenta la sintesi, delle varie ricer- che svolte sul tema, che gode del consenso mondiale più ampio. Ci si è basati su tale documento poiché si desidera fornire ai professionisti dei dati condivisi dai più a livello mondiale, per poterli utilizzare nel loro lavoro e nelle loro argomentazioni. Si desidera inoltre stimolare, in modo costruttivo, l’interesse verso un problema che va a influenzare la nostra vita e quella delle generazioni future