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In the version of this article initially published, the first name of Flora Ascione was listed as “Floriana”; the error has been corrected in the HTML and PDF versions of the article.

In this paper a building-plant system consisting in a housing module with 3D printed walls and a wooden roof is simulated with the dynamic simulation software TRNSYS 18 in coupling with an electric heat pump mainly driven by the electricity of a photovoltaic plant. Energy flows characterizing the system are dynamically assessed and on an annual basis it is evaluated if the condition of nearly Zero Energy Building (nZEB) is reached. Two further indexes - called Building Level of Energy Autonomy (BLEA) and Building Level of Energy Exported (BLEE) - are also calculated to estimate the energy autonomy and the level of energy exported in the proposed configurations. A parametric analysis considering two peak powers for the photovoltaic system (6.12 kWp and 12.24 kWp) and different sizes for the battery (from 2.16 kWh to 25.92 kWh) are investigated. Results highlights that with both photovoltaic (PV) plant layouts a positive yearly energy balance is obtained. The energy dependence decreases progressively till a certain electric storage capacity (15.12 kWh and 17.28 kWh). Over these values the BLEA stabilizes around 94% and 97% with the smallest and largest dimension of the solar field, respectively. In these conditions 44% and 68% of the produced electricity is fed into the distribution grid.

Preserving the historical and artistic heritage is a topic of central interest, especially in countries that have particularly old heritage such as Italy. This study concerns the monitoring of environmental conditions of an ancient church in the center of Naples, a beautiful example of Italian Gothics, which, besides the absolute value of the architecture, even preserves works of art of special significance. The measurement campaign, performed during two typical winter weeks, was necessary to calibrate a dynamic energy model of the church. Then, a radiant floor was designed, to provide a space heating service for the Choir, used for conferences and events, so that the improvement of microclimatic conditions, in winter, can contribute to preserving artifacts (e.g., too cold conditions can induce cracks of wooden materials) and improve occupants' thermal comfort, without compromising the historical/artistic value of the church. The monitoring revealed that the indoor microclimatic conditions do not satisfy the ideal ranges for the conservation of the artistic heritage, and that the indoor environment is uncomfortable for the occupants. The positive effects of the new heating systems were also evaluated, by means of simulations performed starting from the calibrated energy model.

To achieve the goal of decarbonization by 2050, the existing buildings, both private and public, should be renovated. Concerning public buildings, the annual renovation rate of 3% envisaged by Directive 2012/27/EU should be increased to meet the objectives set at the European level in terms of energy efficiency. The stringent targets have been confirmed by the “fit for 55” package. In this paper, a university building in Naples (South Italy, typical Mediterranean Climate) is investigated. It is brought to the standard of nearly zero energy building through different energy efficiency measures. Based on the lifespan of the individual retrofit measure, a reasonable payback period is set. Then the incentive needed to get it is evaluated. What emerges is that greater incentives are required, even up to 80%, for interventions that have a longer lifespan, i.e., the thermal insulation of the building envelope. A form of incentive equal to 40% of the investment, on the other hand, would make it possible to pay off all the interventions in about 10 years, insulation of external vertical walls and roof, replacement of transparent building envelope and installed systems, installation of a photovoltaic system. This solution would make the building a nZEB allowing a reduction of the total primary energy consumption of about 41% and a reduction of CO2 emissions of 46%.

La ricerca indaga il tema dell’abitare nelle aree interne, attraverso un’esperienza progettuale sviluppata nell’ambito del PINQuA, programma bandito dal Ministero delle Infrastrutture e dei Trasporti nel 2020. L’esperienza si basa sull’ipotesi che nelle aree marginalizzate, caratterizzate da decremento demografico, elevato indice di vecchiaia, assenza di servizi di base ed allo stesso tempo da elevato potenziale di innovazione, sia possibile invertire il trend demografico proprio a partire dal recupero edilizio, con l’offerta di alloggi su misura, con elevati standard di qualità e di servizi. Attraverso un approccio sistemico e place-based, la ricerca sperimenta su casi pilota temi legati alle nuove domande d’uso, all’innovazione digitale e green, al welfare di prossimità, alla coesione sociale, mediante un processo multiattoriale e multilivello.

In the version of this article initially published, equation (1) in the Methods section, now reading (Formula presented.), was missing a delta symbol following “R”. The symbol has now been restored in the HTML and PDF versions of the article.

The space conditioning of buildings is liable for more than 10 % of World final energy uses and related CO2-eq emissions. Such share must be drastically reduced to pursue sustainability by optimizing both energy design and devices control. In this frame, space cooling is assuming an increasing weight owing to climate change. Accordingly, this study applies a simulation- and optimization-based framework for the model predictive control (MPC) of space cooling systems. The case study is a nearly zero energy building located in Benevento – Southern Italy, Mediterranean climate – featuring an efficient air-source multi-split system for cooling. The framework is envisioned to provide optimal values of setpoint temperatures on a day-ahead planning horizon to minimize energy cost and thermal discomfort, based on weather forecasts. Accordingly, a Pareto multi-objective approach is applied considering different discomfort indicators to compare the Fanger theory with the adaptive one of ASHRAE 55. The optimization problem is solved by running a genetic algorithm – variant of NSGA II – under MATLAB® environment. The objective functions are assessed via the coupling between MATLAB® and EnergyPlus, using a validated building energy model. The multi-criteria decision-making is performed by setting a limit to discomfort to pick an optimal Pareto solution. The framework is tested addressing a typical day of the cooling season and using monitored weather data to simulate weather forecasts. Different optimal solutions are provided to fit different comfort categories. Compared to a reference control at fixed setpoint – 26 °C – the proposed solutions with similar comfort performance ensure cost savings around 28 %. Besides the proposed hypothetical implementation, the framework can be integrated in automation systems for real-time MPC. The novel contributions of this study lie in the methodology to combine MPC with different thermal comfort models as well as in the results, which provide deeps insights about the application of MPC for the space cooling of nearly zero energy buildings in a balanced climate.

The paper is focused on the evaluation of how the climate changes can influence the performance of buildings designed to be nearly zero energy (nZEB) and on the evaluation of the resilience in term of energy balance. A real case study is used; it is named BNZEB, a single-storey dwelling built in Benevento (South Italy, Mediterranean climate). With five-years monitored meteorological data, both a short-term and medium-term analysis is developed; the first one consists in the evaluation of the energy behavior compared to the first operating year. Then, the energy performance is evaluated considering the medium-term climate projections generated using the CCWorldWeatherGen tool. This analysis, with reference to the case study, suggests to designers and researchers that, in a typical Mediterranean climate, the reduction of the heating demand could compensate the increment in the cooling request. In the worst climatic scenario, the net primary energy could change from 25.4 kWh/m2 year (first year of life, 2017) to 19.5 kWh/m2 year (projection to 2050) with a rate of self-consumption of 85% (80% for 2017). However, a critical point is the operating period of the cooling system. Indeed, an indoor overheating problem could occur during the spring with operative temperature higher than 30 °C; this indicates that in future, the occupants will require higher number of operating hours with most frequent switch off. This could change the results of the energy balance, reducing, for instance, the imbalance between production and consumption that currently occurs in the intermediate periods.

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