Paolo Conti

• Doctor of Philosophy
• Professor (Assistant) at University of Pisa

Energy communities (ECs) are a promising solution to integrate renewable local production with buildings’ systems and services. To exploit renewable energy sources, ECs should be carefully designed, identifying an appropriate mix of prosumers and consumers. In this research, the electrical energy loads of eight dwellings have been monitored for a y...

A persistent dilemma in building energy modeling consists of finding the proper trade-off between accurate results, data availability and limited modeling effort. In fact, quasi-steady state models require a limited number of inputs, however providing often rough results; dynamic tools are instead usually very accurate but involve a huge effort to...

The purpose of our study is to evaluate the surface temperature distribution on a radiant floor, particularly focusing on space cooling operations, to assess the presence of non-uniformities. In fact, knowing the temperature difference between the average superficial temperature and the coldest spot can be a useful indication for condensation preve...

Radiant floor heating systems have become a reference technology, but their use for cooling purposes has proven inconvenient in many applications due to their reduced cooling capacity and condensation issues. Nonetheless, potentialities and drawbacks of radiant floor cooling systems have been frequently addressed and simulated, given the large pote...

This paper presents the development of geothermal applications in Italy in the 2017-2020 period for both the power and the heating & cooling sectors. Enel Green Power is the only geo-electricity producer in Italy. At the end of 2020, the installed geo-capacity was 915.8 MWe, supported by 34 power plants and 37 generation units. In 2020, the gross e...

The paper deals with the sizing and the arrangement of thermal energy storages in heat pump systems for building service. Partial-load losses are an increasingly important phenomenon in high-efficiency buildings, even for inverter heat pumps, due to the low average thermal demand compared to the installed capacity. The paper discusses partial-load...

The paper provides results from a hardware-in-the-loop experimental campaign on the operation of an air-source heat pump (HP) for heating a reference dwelling in Pisa, Italy. The system performances suffer from typical oversizing of heat emission devices and high water-supply temperature, resulting in HP inefficiencies, frequent on-off cycles, and...

This paper proposes an analytical method for the dynamic thermal simulation of energy piles with a short time resolution (e.g., tens of minutes) as an alternative to numerical approaches, which require relevant computational resources. The discussion is tailored to the implementation of analytical models in dynamic energy simulation software for bu...

The paper provides a methodology for the optimal control of heating, ventilation, and air conditioning (HVAC) systems used in public buildings, with the purpose of obtaining high comfort and safety standards along with energy efficiency. The combination of the two concurrent objectives of minimizing energy use and guaranteeing high standards of occ...

Worldwide increasing awareness of energy sustainability issues has been the main driver in developing the concepts of (Nearly) Zero Energy Buildings, where the reduced energy consumptions are (nearly) fully covered by power locally generated by renewable sources. At the same time, recent advances in Internet of Things technologies are among the mai...

The paper analyzes the design of a typical solution for a smart energy system. It examines a particular plant, evaluating the integration of a Photovoltaic (PV) system and a Ground-Source Heat Pump (GSHP) for residential building service. The idea is to develop a system that maximizes self-consumption of the renewable energy generated by a small-si...

This paper aims at proposing fast and plain design tools to evaluate the best energy application for deep borehole heat exchangers, exploiting geothermal resources. Exergy efficiency has been chosen as a performance index. Five possible utilization solutions have been analyzed: district heating, adsorption cooling, ORC power production, a thermal c...

The geothermal sector has a strength point with respect to other renewable energy sources: the availability of a wide range of both thermal and power applications depending on the source temperature. Several researches have been focused on the possibility to produce geothermal energy without brine extraction, by means of a deep borehole heat exchan...

Estimating and optimizing the dynamic performance of a heat pump system coupled to a building is a paramount yet complex task, especially under intermittent conditions. This paper presents the “hardware-in-the-loop” experimental campaign of an air-source heat pump serving a typical dwelling in Pisa (Italy). The experimental apparatus uses real piec...

The performance of ground heat exchanger systems depends on the knowledge of the thermal parameters of the ground, such as thermal conductivity, capacity, and diffusivity. The knowledge of these parameters often requires quite accurate experimental analysis, known as a thermal response test (TRT). In this paper, after a general analysis of the vari...

The paper deals with the multi-objective optimization of the HVAC control in museums. Scientific literature, technical standards and museums stakeholders mainly focus on the single-objective of artefacts conservation. However, a major attention should be paid at visitors’ comfort and energy consumption, without compromizing artwork integrity. In th...

This paper presents an overview on the development of thermal applicationsof geothermal energy in Italy since the last WGC2015. The Italian situation is described till the end of 2017, being this the most recent year for which data are available at the writing date of this report. The total installed capacity amounts to 1424 MWt, with a correspondi...

Heat pumps represent a link between different energy vectors and their application in thermal and electrical grids can improve the overall operational flexibility of the system. In this work, the optimal integration of electrically driven heat pumps within a hybrid distributed energy system is investigated. A multi-objective stochastic optimization...

The COVID-19 pandemic is changing the way individuals, worldwide, feel about staying in public indoor spaces. A strict control of indoor air quality and of people’s presence in buildings will be the new normal, to ensure a healthy and safe environment. Higher ventilation rates with fresh air are expected to be a requirement, especially in education...

The paper presents a comprehensive energy and exergy analysis of a possible geothermal power plant located in the geothermal district of Campi Flegrei (Italy), made of a coaxial WellBore Heat eXchanger coupled to an Organic Rankine Cycle. We have accounted for all system components: the ground source, the WellBore Heat eXchanger, the Organic Rankin...

This work presents an optimization strategy and the cost-optimal design of an off-grid building served by an energy system involving solar technologies, thermal and electrochemical storages. Independently from the multi-objective method (e.g., utility function) and algorithm used (e.g., genetic algorithms), the optimization of this kind of systems...

This paper presents an overview on the development of geothermal energy applications in Italy for the year 2018 for both electricity generation and thermal uses. Geothermal power plants are located in Tuscany, in the two "historical" areas of Larderello-Travale and Mount Amiata. Thermal energy applications are widespread over the whole Italian terr...

This paper presents the application of the United Nations Framework Classification for Resources (UNFC) to an open-loop ground source heat pump (GSHP) in Italy. The UNFC is a universal classification system aimed at facilitating the comparison and the decision-making process for all the stakeholders involved in a specific energy project. The classi...

The present paper assesses the capability of a cost-optimal control strategy to activate demand response actions in a building equipped with an air-source heat pump coupled with a water thermal storage system. Commencing with a reference scenario where no demand response actions are considered, the electricity consumption pattern and the operationa...

This paper analyzes the use of hybrid photovoltaic/thermal (PVT) collectors in nearly zero-energy buildings (NZEBs). We present a design methodology based on the dynamic simulation of the whole energy system, which includes the building energy demand, a reversible heat pump as generator, the thermal storage, the power exchange with the grid, and bo...

Micro-district heating networks based on cogeneration plants and renewable energy technologies are considered efficient, viable and environmentally-friendly solutions to realizing smart multi-energy microgrids. Nonetheless, the energy production from renewable sources is intermittent and stochastic, and cogeneration units are characterized by fixed...

The heat transfer process in energy piles is strongly affected by the heat capacity of such foundation elements. This phenomenon is more pronounced for energy piles compared to borehole heat exchangers, because of the lower slenderness of the former compared to the latter, and involves axial thermal gradients. In literature, capacity effects of ene...

The present paper analyses the cost-optimal sizing and hourly control strategy of a hybrid heat pump system for heating application, composed by an electrically-driven air source heat pump and a gas boiler. These hybrid systems represent a promising solution for the energy retrofit of existing buildings and new installations, being able to increase...

In museums, hygrothermal conditions must be carefully controlled by HVAC system to avoid artwork degradation. Higher energy requirements are needed for the maintenance of the suitable thermal environment. Moreover, a comfortable thermal sensation is needed for a positive museum experience. In light of current policies on energy efficiency, we propo...

This paper proposes a dynamic analytical method to simulate the thermal performances of truncated cone helix ground heat exchangers (i.e., the so-called “energy baskets”). These ground-coupled devices are attractive solutions to reduce the initial cost of ground-coupled heat pump systems, as they require lower cost to be drilled and installed with...

The ongoing decarbonisation process of the current energy system, driven by the EU directives, requires that more renewable energy sources are integrated in the global energy mix, as well as policies promoting investments in new low-carbon technologies, energy efficiency and grid infrastructure. The technical integration of renewable energy sources...

In museums, artworks preservation is hampered by several factors, in particular temperature and relative humidity as inappropriate values of these parameters can cause biological, mechanical, and chemical degradation. Thus, HVAC systems must be able to maintain specific suitable indoor microclimate also in critical conditions, such as variation of...

This paper deals with the problem of an infinite cylindrical heat source embedded into a saturated porous medium and subject to a cross-axial Darcian flow. Only forced convection is considered. We derived the transient dimensionless solution through a combined analytical – numerical method consisting of four steps: (a) a preliminary dimensional ana...

This work reviews and compares suitable models for the thermal analysis of forced convection over a heat source in a porous medium. The set of available models refers to an infinite medium in which a fluid moves over different three heat source geometries: i.e. the moving infinite line source, the moving finite line source, and the moving infinite...

This article provides plain and handy expressions to decide the most suitable analytical model for the thermal analysis of the ground source in vertical ground-coupled heat pump applications. We perform a comprehensive dimensionless analysis of the reciprocal deviation among the classical infinite, finite, linear and cylindrical heat source models...

This document provides the specifications for the application of the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009) incorporating Specifications for its application to geothermal resources. The intended use of this document is in conjunction with UNFC-2009 and the Specifications for the...

This article deals with analytical heat transfer modeling of double-U borehole heat exchangers. We propose five original, plain and comprehensive expressions to evaluate both heat flux at BHE surface and return temperature with respect to any geometrical characteristic, flow arrangement within U-ducts (series or parallel), and operative condition (...

In this paper, the second of two parts, we apply the cost-optimal design method illustrated in Part 1 [1] to a case study. We select a farm hostel located in Enna, Italy, as the local climate and the required energy services are suitable for the development of a solar-assisted nearly zero-energy building. The system is connected to the electric gri...

This paper deals with the cost-optimal sizing of solar technologies for thermal and electrical needs of residential or tertiary nearly Zero-Energy buildings. The proposed design procedure is based on lifetime simulation of building loads and energy systems; therefore, according to proper cost-optimality considerations, it is possible to find the be...

SEAS is an energy auditing software that can simulate residential, office, school, and hospital buildings, providing energy requirements for heating, domestic hot water production, ventilation, lighting, and other electrical uses.

Radiant heating coupled to a heat pump is a particularly energy-efficient system, recommended in new constructions. However, the potential energy savings associated with this high thermal inertia system can only be achieved with appropriate control laws, to be tested in a full building–plant simulation environment. The developed transient code conc...

This paper is mainly aimed at stressing some fundamental features of the GSHP design and is based on a broad research we are performing at the University of Pisa. In particular, we focus the discussion on an environmentally sustainable approach, based on performance optimization during the entire operational life. The proposed methodology aims at i...

Energy piles are heat capacity systems that have been increasingly exploited to provide both supplies of energy and structural support to civil structures. The energy and geotechnical behaviours of such foundations, which are governed by their response to thermo-mechanical loads, is currently not fully understood, especially considering the differe...

This work proposes an innovative approach to the ground source evaluation for heat pump systems. The initial characterization of the soil (e.g. thermo-physical properties, temperature…) is integrated with classical considerations about HVAC design. In particular, we propose to analyze the viability of a ground source project through the evaluation...

The present work aims at identifying the relative influence of GSHP subsystems (viz. ground source, earth heat exchangers, heat pump unit, pumping devices) on the overall efficiency and the limits to which technological improvements should be pushed (because, beyond these limits, only minor benefits may be achieved). To this end, an analysis of the...

Questo e-book ha lo scopo di rendere immediatamente disponibile, in modo schematico, l’insieme di novità introdotte con gli ultimi cambiamenti apportati alle norme sulla Certificazione Energetica. Ci si riferisce alle norme UNI/TS 11300, parti 1 e 2, pubblicate inizialmente nel 2008 e per le quali sono appena uscite (2 ottobre 2014) versioni aggior...

After heating and cooling, thermal balneology was in 2010 the second most important sector of direct uses in Italy, with 149 thermal localities using hot water for balneotherapy, with no combination with other direct uses. This is why, in 2009 and 2010, UGI conducted regional studies on their water and energy balance to investigate the possible opt...

The paper reports the data related to geothermal direct uses in Italy