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The theme of the energy requalification of historic buildings is addressed considering the Palaeontology Museum of Naples (Southern Italy). It is assessed whether, through non-invasive methods and without intervening on the building envelope, it is possible to obtain internal hygrothermal parameters suitable to allow both occupants’ thermal comfort and satisfactory conservation conditions for the archaeological finds. In addition, a relevant reduction of energy requirements and CO2 equivalent emissions is required. Dynamic energy simulations are conducted regarding both the current configuration and the various possible modifications concerning the air conditioning system; the model is calibrated by comparison with real energy consumption data. The electric and primary energy are compared for the various cases. Furthermore, the internal hygrothermal conditions for occupants’ thermal comfort and for conservation of the archaeological finds are analysed. Finally, the possibility of inserting a suitable and minimally invasive photovoltaic system is evaluated and an almost ‘Double Plus-Zero Energy Building’ is obtained.

Earth-to-air (EAHX) and/or air-to-air (AAHX) heat exchangers can be conveniently inserted in heating, ventilation, and air conditioning (HVAC) systems to obtain relevant energy saving. In this article, the subject is analyzed for an office building located in two Italian localities: Milan (Northern Italy, with cold winters and hot summers) and Palermo (Southern Italy, with mild winters and very hot summers). A dynamic building energy performance simulation software is used to simulate a designed office building. The HVAC system is based on fancoils and primary air, with or without EAHX and AAHX. The seasonal analysis shows better energy results for AAHX in winter and EAHX in summer, respectively. The yearly analysis shows that the EAHX is preferable in hot or mild climates. Successively, the EAHX and AAHX are combined: based on the previous seasonal results, the first one is activated in summer, while the second in winter. The combination of the two technologies is preferable for Milan (energy saving up to about 75%) compared to Palermo (saving up to about 60%). Finally, the analyses of the equivalent CO2 emissions and discounted payback are reported.

This paper investigates air-to-air (AAHX) and earth-to-air (EAHX) heat exchangers, to reduce the energy requirements of air conditioning systems for office buildings. The AAHX considered is of static type with a partition wall and allows recovering both sensible and latent heat. The EAHX technology exploits the capability of the ground as energy storage, through a system of earthed air ducts laid horizontally. In summer, the ground usually presents temperatures lower than outside ventilation air temperatures, while in winter it could have, in some hours/days, a temperature higher than the outside air. Three European cities are considered: Palermo (southern Italy), with mild winters and very hot summers; Milan (northern Italy), with cold winters and hot summers; Berlin (Germany), with very cold winters and quite hot summers. The analysis is performed by means of EnergyPlus, a dynamic building energy simulation software, with reference to the same, newly designed office building, with or without heat recovery systems. The air conditioning system is based on fan-coils and primary air, and the EAHX (or the AAHX) is inserted in the first part of the primary air-handling unit. The research shows that in winter the use of the AAHX reduces the energy requirement much more than the EAHX, while in summer the EAHX is preferable. Moreover, the annual analysis shows that the use of the EAHX is more convenient in hot climates. The case of coupled heat exchangers (AAHX + EAHX) is also investigated. The evaluated discounted payback is about 6–9 years for the EAHX (3–5 years if an incentive of 20% is considered) and 1–3 years for the AAHX (less than 1 year with the incentive).

In this research communication we report on the diversity of yeast and mould species in 69 samples of milk and different dairy products from three plants located in Umbria, central Italy. Isolates were characterised both macroscopically and microscopically and then identified by PCR and genome sequencing of the ITS region and the D1–D2 domain of the large-subunit rRNA gene for filamentous fungi and yeasts, respectively. Out of the 69 samples analysed, 51 (73.9%) tested positive for the presence of yeasts, whereas moulds were detected in 25 (36.2%) samples. A total of 9 yeast species belonging to 8 different genera and 13 mould species belonging to 6 different genera were isolated. The most common genera isolated were Debaryomyces and Kluyveromyces among the yeasts and Penicillium and Galactomyces among the moulds. Microbiota play a key role in the formation of flavour, aroma, texture and appearance of dairy products. This complex microbial ecosystem includes both cultured and external bacteria, yeasts and moulds. Some of them have an important role in the production of cheeses, whereas others are responsible for dairy product spoilage, resulting in significant food waste and economic losses. Some species can produce mycotoxins, representing a potential hazard for the consumer's safety. This study provides interesting information on the diversity of fungi species in dairy products from central Italy that can be of major importance to identify these products and to develop adequate strategies for fungal spoilage control and consumer safety.

A passive strategy to reduce the energy consumption of existing buildings is to improve the thermal insulation of the opaque building envelope and insert windows with low thermal transmittance U. But what is the best compromise between cost of intervention and reduction of primary energy? The aim of this paper is to answer this question using the innovative cost-optimal methodology and a dynamic energy simulation software. The case study refers to an existing school in central Italy. Eight passive strategies are analysed, combining different insulation thicknesses and types of windows. Furthermore, a comparison between cost-optimal methodology and discounted payback analysis is reported. Finally, a sensitivity analysis on parameters influencing the cost-optimal method is conducted. The lowest primary energy is obtained considering an insulation thickness of 12 cm and windows with U of 1.10 W/m2 K, while the best case using the cost-optimal methodology refers to a low increase in insulation thickness.

A new concept of building is represented by Zero Energy Buildings (ZEBs). This paper evaluates the possibility to obtain a NZEB (for office building) by using only “on-site” renewable energy, solely on the roof. A dynamic energy simulation code, EnergyPlus, is used. Two different Italian climatic zones (Palermo and Naples) and two typologies of building are considered: square or rectangular basis. For the building with square basis, the energy self-sufficiency is kept up to a higher number of the building levels (8 for Naples, 10 for Palermo) compared to the case of rectangular basis (7 levels for Naples, 9 for Palermo).

Nowadays the study of Net Zero Energy Buildings (NZEBs) is fundamental, because they are the main strategy to reduce the building energy demand and CO2-equivalent emissions. This paper analyses a case study concerning a multipurpose building located in Palermo (Southern Italy), and evaluates the benefits related to the use of an earth-to-air heat exchanger in a NZEB, in terms of energy saving and reduction of CO2-equivalent emissions, for a Mediterranean climate. The chosen building envelope is thermally performing. The HVAC system consists in fan-coil units connected to an air-to-water heat pump, and mechanical ventilation. The energy demand is reduced by an earth-to-air heat exchanger that pre-heats the ventilation outside air in winter and cools it in summer. The optimization of the heat exchange with the ground is a key-element to reduce the primary energy requirements and CO2-equivalent emissions, especially during summer. Moreover, this paper assesses the possibility to obtain a NZEB using only on-site renewable energy (on the roof of the building), with and without the earth-to-air heat exchanger. The energy analysis is carried out by means of a dynamic building simulation engine, namely EnergyPlus. In addition, a thermal performance and an environmental analysis are performed.

In school buildings, the relationship between energy requirements and occupant thermal-hygrometric comfort plays an important role because these buildings are great energy consumers also as the current rules impose large rates of ventilation outside air for classrooms. The goal of this paper is the thermal and energetic comparison of various air-conditioning systems that are appropriate for school buildings. Among the different suitable HVAC systems for schools, the following types are considered: All-Air system (with constant air volume and heat recovery) and zone heating coils; radiant heating floor panels and primary air; fan-coils and primary air. The analyses are performed on a designed new school building, by means of a dynamic building energy simulation software (Design Builder), based on Energy Plus engine. The simulations are conducted to obtain the trends of various internal environmental parameters for both winter and summer, i.e.Temperature, relative humidity and PMV (Predicted Mean Value) index in one classroom. In cooling and heating conditions, the HVAC systems are active, while in the intermediate seasons only mechanical ventilation is working. This study evaluates the performances of different HVAC systems from an energy, thermal comfort and economic point of view. The analyses are conducted for Rome, characterized by Mediterranean climate.

At present, the office buildings built in Italy before the first energy regulations of the '70s show a growing energy consumption for heating and cooling. The electrical energy demand for summer cooling is increasing, too. Among the possible strategies, thermal insulation of the building envelope is a common solution to reduce energy needs. However, in buildings with high internal thermal loads and/or located in climates characterized by warm summers and mild winters, an excessive insulation thickness, although in compliance with legal requirements, may be counterproductive. In this paper, by using a dynamic energy simulation software (Design Builder), a case study is analyzed concerning the energetic and economic impacts of thermal insulation applied on the external side of an existing office building. The chosen Mediterranean localities are Palermo, Rome, Milan and Cairo. Increasing internal thermal loads (10, 20, 30 W/m2) are considered. The results show that hyper-insulation of buildings is not convenient in the considered climates. In two localities (Palermo and Rome), the optimal insulation thickness is lower than that needed to meet the regulations on energy saving in buildings. Finally, PMV (Predicted Mean Vote) index for some disadvantaged rooms is shown to consider also the thermal comfort requirements.

Attualmente gli edifici adibiti ad ufficio costruiti in Italia prima dell’entrata in vigore delle prime leggi sul contenimento del consumo energetico degli edifici (L. 373/76) sono caratterizzati da un crescente consumo di energia per il riscaldamento in inverno e per il raffreddamento estivo dei locali. È soprattutto in crescita significativa la domanda di energia elettrica per il raffreddamento. Tra le possibili strategie per ridurre le richieste energetiche degli edifici, l’isolamento termico dell’involucro edilizio è una soluzione frequente. Tuttavia, in edifici con elevati carichi termici interni e/o situati in climi con estati calde ed inverni miti, un eccessivo spessore di isolante può risultare energeticamente penalizzante, sebbene in linea con gli attuali limiti di legge. In questo articolo è analizzato un caso di studio, sviluppato con un software di simulazione energetica dinamica (Design Builder), che riguarda l’impatto energetico ed economico dell’isolante termico applicato sul lato esterno di un edificio esistente adibito ad uffici. Le località scelte in ambito mediterraneo sono Palermo, Roma, Milano e Il Cairo e come carichi termici interni sono considerati 10, 20 e 30 W/m2. I risultati mostrano che uno spessore eccessivo di isolamento termico degli edifici non è conveniente nei climi più caldi. Inoltre, per due località (Palermo e Roma), lo spessore ottimale di isolante è minore di quello necessario a soddisfare i requisiti legislativi attuali sul contenimento dei consumi energetici negli edifici. Infine, è stato valutato anche l’indice PMV (“Predicted Mean Vote”, cioè voto medio previsto) in alcuni ambienti svantaggiati, per tener conto anche del comfort termico degli occupanti.

In historical centres, the buildings are characterized by pitched roofs, sometimes not insulated, with low thermal inertia and coated in brick tiles with low solar reflection factor. So, the attics show high energy costs for heating and cooling. This paper analyses the energy saving obtainable by applying innovative surface finishes on interior and exterior surfaces of opaque envelope components of existing buildings. This simple and inexpensive retrofit action determines energy cost reductions for heating and cooling, but also benefits regarding indoor thermal comfort and useful life of buildings, because condensation problems and thermal shock are reduced; moreover, it preserves the architectural and chromatic characteristics of the building envelope. The analysis is performed by means of a building energy simulation code, considering typical HVAC systems for various Italian and European cities. A technical-economic and environmental investigation is also performed. Thermal energy needs of buildings for summer cooling can be reduced up to 60% by applying “cool paints” on the external surface of walls and roof, while internal low infrared emissivity coatings can reduce winter thermal requirements up to 12.5%. Significant primary energy savings for heating and cooling and reductions of greenhouse gas emissions (up to 60%) can be obtained, as well as a payback value of few years in most cases.

This paper investigates the best strategies to reduce the energy requirements of air conditioning systems for office buildings by using two different types of technology: Air-to-Air (AAHX) and/or Earth-to-Air (EAHX) heat exchangers. The AAHX considered is a static type of heat recovery with partition wall, which allows recovering both sensible and latent heat by means of convection and conduction mechanisms via partition wall. Referring to EAHX, this technology exploits the capability of the ground as energy storage, through a system of earthed air ducts laid horizontally. In summer, the ground usually presents temperatures lower than outside ventilation air temperatures, while in winter it could have, in some hours/days, a temperature higher than the outside air. In the examined case, the air conditioning system is based on fan-coils and primary air, and the EAHX (or the AAHX) is installed upstream of the primary air-handling unit. The performance of the two examined technologies are analysed for three European cities with different climates: Palermo (Southern Italy), with mild winters and very hot summers; Milan (Northern Italy), with cold winters and hot summers; Berlin (Germany), with very cold winters and quite hot summers. The analysis is performed by means of EnergyPlus, a dynamic building energy simulation software, with reference to the same designed new office building with or without heat recovery systems. The research shows that, for all the analysed climates, in winter the use of the AAHX reduces the energy requirement much more than the EAHX, while in summer the EAHX is preferable. Moreover, the annual analysis shows that the use of the EAHX is more convenient in hot climates. The case of coupled heat exchangers (AAHX+EAHX) is also investigated. A further analysis is performed on the benefits that the two analysed technologies allow in different seasons.

Energy consumption for heating and cooling of Italian office buildings is growing. In particular, there is an increase in the demand for electricity for cooling in the summer. Thermal insulation on the external side of the buildings is a very usual strategy to reduce energy demand for air-conditioning systems. However, a too high thickness of insulating material, even if complying with current legislative requirements, can be disadvantageous in buildings characterized by great internal thermal loads and/or located in climatic contexts with mild winters and hot summers. In this paper, the energetic and economic influence of external thermal insulation is evaluated by using energy simulations under dynamic conditions (DesignBuilder software) for a case study. The analysis is performed for various cities (Palermo, Milan and Cairo) and for different values (10, 20, 30 W/m2) of internal thermal loads. According to the recent and innovative “cost-optimal” methodology, optimal insulation thicknesses are derived, and the results demonstrate the need to avoid excessive insulation of buildings to obtain the highest energy saving. Finally, an integration of the “cost-optimal” methodology is proposed considering also the topic of thermal comfort; this modification allows to obtain other optimal solutions compared to the basic calculation procedure.

A great portion of the global energy consumption depends on existing buildings. So, energy saving and related CO 2 emission reduction are important measures. This paper analyses the incidence of innovative surface finishes on the cooling and heating energy demand of existing buildings. These easy and cheap measures preserve the little living spaces, limited height and the architectural/chromatic characteristics. The analysis is conducted for various European cities, by using a dynamic energy simulation software. The primary energy required by the HVAC systems on seasonal and annual basis is evaluated and relevant energy saving (up to 21% on annual basis) is obtained. Finally, a technical-economic analysis is performed and interesting payback values are obtained (2.5-11 years in the best cases; 2–10 years, when a tax deduction of 35% is considered).

In recent years, different types of solar shading devices have been proposed, depending on building orientation, location, window characteristics, etc. They can contribute to improve or worsen building thermal and lighting performances both from an energy and comfort point of view. The present paper reports a critical analysis of some studies that investigate shading devices’ effects on building thermal and/or lighting performances. This article points out the difficulty in comparing the different results given the lack of uniformity between the studies, since they analysed buildings with different characteristics, locations and using various indices. Therefore a protocol to carry out this type of studies should be developed in order to allow the comparison of the different research investigations performed all over the world. Moreover, this paper shows that thermal comfort, economic and environmental aspects related to the use of shading devices were rarely analysed.

Final report of the BUILD UP Skills project I-TOWN IEE/13/BWI/721/S12.680178