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The paper presents the design state of a smart car park shelter for electric vehicle in the campus of the University of Palermo. The car park is supplied by the main grid and by a 40 kW photovoltaic system and is equipped with a Li-ion battery storage system with capacity 42 kWh. The hybrid plant is designed in order to operate both in connection with the main grid and in stand-alone mode, supplying, in this case, all car park's loads and providing one recharge to an electric vehicle. Moreover, the energy storage system and, eventually, the battery of one or more cars with V2G technologies, can be managed for providing ancillary services to the grid. In the paper, the design of the system and the choice of all components is presented. Finally, the environmental impact of the diffusion of such installations on the energy system is discussed.

In this paper, a comprehensive review is performed on hybrid systems using electrical Heat Pumps for Heating, Ventilation & Air Conditioning systems and Domestic Hot Water production using case studies from 2016 to 2022. This work particularly focuses on studies that investigated systems with electrical Heat Pumps assisted by a gas boiler. Some studies that considered the exploitation of renewable energy sources, but not as a whole sub-stitute for fossil sources, have also been included. In particular, the analysis investigated the layouts of the systems by considering the type and the size of the components, the control methods applied (by distinguishing rule-based control methods and predictive control methods), and the main performance indices used to calculate energy, exergy, environmental and economic performance. Most of the analysed studies demonstrated that the hybrid systems could be very advantageous if the switch or the integration of the two generators is well managed. Nevertheless, the energy and economic performances are very different for each system studied. They are highly influenced by the control strategies implemented and by the objective functions adopted. Furthermore, climate can influence performance while affecting the Coefficient Of Performance of the heat pump and the availability of energy sources. Regarding economic issues, the systems' performances vary according to specific Country tariff structures. The review reported a promising research activity also pursued by manufacturers of components and equipment. Nevertheless, the paper highlights new possible research and development directions.

Nel 1943 Mario Sironi dipingeva “Il Gasometro”, riprendendo in toni apocalittici il tema del paesaggio urbano. Sono poi passati quasi quaranta anni dall’aprile 1977, mese in cui uscì il numero monografico 135 di “Edilizia Popolare”, con i primi progetti per la riconversione della Bovisa nel quadro di rinnovate relazioni metropolitane; una attenta cronologia metterebbe in luce il ruolo cruciale che quest’area ha giocato nel dibattito sulle forme insediative di Milano e nella più specifica vicenda dell’articolazione territoriale del Politecnico; una lunga storia, dunque, con profondi connotati simbolici e ideologici, che ha visto sedimentare ampio dibattito e vasto patrimonio di conoscenze - oltre a evidenti contraddizioni - dai quali non si può prescindere, ma che vanno tuttavia attualizzati secondo un nuovo punto di vista. Nel progetto per il nuovo insediamento della Bovisa prende corpo il confronto tra due scale, due misure del progetto di architettura. La prima, quella dell’ “idea di città” riferita al principio ordinatore della direttrice nord-ovest; infatti, come già altrove rimarcato, Milano è da sempre città di dimensioni contenute ma di rapporti territoriali estesi, storicamente radicata a un sistema di itinerari e direttrici di lunga e breve distanza, che si riflette nella compresenza delle diverse scale, appunto, con progetti e realizzazioni che evocano i grandi spazi congeniali a questo carattere di portualità. Ma soprattutto, ben al di là delle questioni stilistiche e delle pur notevoli sperimentazioni progettuali che Milano ha proposto, si sottolinea il valore ideologico e dimostrativo di una interpretazione coerente della forma urbis, intesa come espressione originale di civiltà, il cui studio ha valore di principio nell’accezione autenticamente cattaneiana del termine. Così proprio nella dimensione urbana del progetto, si vuole rintracciare anche quel senso di possibilità, quella suscettibilità alle trasformazioni future che nella sola prospettiva locale possono sembrare inattendibili. La seconda misura si ritrova nelle relazioni minute della prossimità, o del “quartiere” nella terminologia del Movimento moderno, fortemente radicata nella municipalità suburbana prima, nel “rione”, poi nella zona del decentramento amministrativo, che per Bovisa continuano a giocare un ruolo di principale importanza. Il progetto seleziona due giaciture che si impongono come generatrici: quella dei campi, occupati poi dalle fabbriche e dalle geometrie dei raccordi ferroviari, che permane entro l’area della “goccia”; quella dell’asse di via Bovisasca, cui si appoggia la maglia regolare del quartiere nel quale, piazzale Bausàn, capolinea delle linee tranviarie, prende carattere di luogo centrale. Il rigore di questa geometria stabilisce l’impianto dell’academical village, riprendendo la definizione e il tipo inaugurati da Thomas Jefferson, impostato sul vuoto del grande spazio rettangolare, con i lati maggiori bordati dagli edifici allineati e aperto sul quarto lato.

Nel progetto per il nuovo insediamento della Bovisa prende corpo il confronto tra due scale, due misure del progetto di architettura. La prime, quella "dell'idea di città" riferita al principio ordinatore della direttrice nord-ovest; infatti, come altrove rimarcato, Milano è da sempre città di dimensioni contenute ma di rapporti territoriali estesi, storicamente radicata a un sistema di itinerari e direttrici di lunga e breve distanza, che si riflette nella compresenza delle diverse scale, appunto, con progetti e realizzazioni che evocano i grandi spazi congeniali a questo carattere di portualità.

The paper shows a comparative analysis of the performances of two typologies of solar assisted cooling systems for building applications. In particular, Life Cycle Assessment (LCA) methodology is applied to assess the energy and environmental impacts of solar-assisted, heat-driven chillers and conventional compression chillers driven by grid-connected and stand-alone photovoltaic configurations. LCA is applied in compliance with the international standards of ISO 14040. System boundaries are defined following a “cradle to grave” approach, taking into account all the life-cycle phases including the raw materials supply, the production of the components of the plant, the operation and maintenance, and the end-of-life. The operation step of the assessed systems is simulated with TRNSYS models. Two reference buildings are modeled for two different sites, Palermo (Italy) and Rio de Janeiro (Brazil), according to local practices and regulations. The building models are normalized to have the same peak cooling demand (12 kW). The results show that the assessed energy and environmental performances of the grid-connected systems are usually better than the others for both climates, while the manufacturing process of storages in the stand-alone configurations does not allow these solutions to be competitive yet. Furthermore, the impact of the high average national electricity conversion efficiency in Brazil on the results is analyzed and discussed.

Ensuring optimum interior lighting is a topic of great importance, as this influences not only the well-being of users but also the optimal performance of visual tasks. Lighting can be natural, but if not sufficient, it can be compensated with artificial lighting. This study highlights a methodology for designing a new lighting system that takes into account both technical and economic aspects. The method was applied to an existing school located in southern Italy, in which the electricity consumption is related to the current lighting system. The school is chosen as being representative of the construction type and layout of many local schools. In addition, the coexistence of several visual tasks with different design requisites (e.g., illuminance levels) makes the school a very complex environment. The school lighting is modelled in Google SketchUp and imported into Daysim to simulate the yearly and hourly daylight indoor contribution. Dialux Evo has been used to simulate and design artificial lighting. The results show a reduction of energy consumption of 33% with the simple replacement of fluorescent luminaires with LEDs, while the LED lamp dimming and modulation for rows of luminaires leads to a 95% reduction in energy consumption compared with the current state.

Results from the DAYKE-Italy project are presented. An investigation on daylighting in eight classrooms in five Italian universities was carried out through a combined approach: an ad-hoc survey administered to students to investigate how they perceive daylight in classroom, and numerical simulations (DIVA + ALFA) to calculate a set of objective metrics (daylight, circadian, and energy-related). A sample of 542 questionnaires was collected through two sessions and the subjective judgments were correlated to objective metrics. Results from descriptive and statistical analyses showed: (i) the correlation was significant for all daylight metrics: among them, average daylight factor and annual light exposure performed higher correlations compared to daylight autonomy, spatial daylight autonomy and useful daylight illuminance; (ii) rooms with a scarce or an optimal daylight provision (according to standards) were rated with comparable subjective score; (iii) the equivalent melanopic lux showed a higher correlation than daylight metrics based on the horizontal workplane; (iv) energy saving up to 50% can be achieved in the presence of high daylight provision and through daylight responsive controls; however, a relamping of fluorescent systems with LED system is recommended to optimize the consumption; furthermore, estimated saving correlated significantly with objective metrics.

Daylighting is a strategic topic to achieve sustainable buildings, so it is more and more imperative that it is implemented in architecture curricula to prepare a new generation of daylighting-oriented practitioners. In this frame, the DAYKE project (Daylight Knowledge in Europe) was set up to explore the level of knowledge about daylighting among European professionals and students. DAYKE-Europe was replicated as DAYKE-Italy to study the knowledge of daylight standards, metrics and software among Italian architecture students, and to compare it to that observed within DAYKE-Europe. A sample of 542 questionnaires were collected in five universities. Primary outcomes were: (i) a general low level of knowledge on daylighting was observed; the most cited metrics were the average daylight factor and the geometrical window-to-floor ratio, while climate-based daylight metrics were rarely mentioned; (ii) master science M.Sc. students reported more knowledge on daylight metrics and regulations than bachelor B.Sc. students, while the implementation of daylight metrics and strategies in projects was mainly deficient among B.Sc. students; (iii) compared to European students (DAYKE-Europe), Italian students showed a higher knowledge of daylight metrics and software (especially as for M.Sc. students), while the opposite was observed for standards, regulations and protocols. Based on the results, a reconsideration of daylight education in architecture curricula is recommended.

The present work relies on the topic of energy storage for Heat and Electricity applied to Heat Pump Water Heaters coupled with photovoltaic plants for Domestic Hot Water production. The main idea is to evaluate the possibility to exploit the water tank as heat storage for the produced photovoltaic energy and, where appropriate combined with electrical storage. For this reason, two heat pumps with different volume size have been chosen and smart control strategies have been applied while monitoring the water temperature in the tank. Calculations account on tapping profile inferred from monitored data of a representative end-user in a Mediterranean small island. Results show how the combination of smart control strategies and battery systems is the most suitable solution in order to fulfil the domestic hot water energy demand by renewable sources while maintaining comfort requirements.

The achievement of United Nations Sustainable Development Goals, related to energy and resource use, is a critical issue for small and insulated communities. In many minor islands, solar energy is not correctly exploited, and electrical heaters are connected to weak grids with very a high share of generation by fossil fuels. As a consequence, there is the necessity to assess the potential and the suitability of diffusion of alternative systems to avoid dependency on the electrical grid and reduce carbon emissions. This paper aims to evaluate the technical and economic performances of some alternative systems exploiting renewable energy for domestic hot water production. Four different systems were simulated and studied: a heat pump connected to the grid, a heat pump coupled with a photovoltaic plant, a heat pump combined with a solar thermal collector, and a solar thermal plant. Moreover, heat and electricity storages were studied for reducing impacts on the distribution network. The work presents data gathered for a study on energy-retrofit strategies on Lampedusa Island (Italy, 35&deg, 30&prime, 56&Prime, north (N), 568 degree-days). Finally, to select the most cost-effective plant, an economic analysis of the chosen systems was carried out. This analysis shows that the best net present values are associated with the heat pump (HP) coupled with a stand-alone PV system and a small battery and solar thermal-assisted HP. The shortest payback time was calculated for the solar thermal system.

The application of “shiftable” or “modulable” load (i.e. washing machine, dishwasher, etc.) in a Smart Grid, can provide energy saving or modify the power flows in the grid, allowing a reduction of the electrical power peak. This paper explores the possibility to modulate the indoor artificial lighting to support this reduction. The study examines the impact of two different measures of power shaving. On the one hand, the change of Correlated Colour Temperature of the light source, and, on the other hand, the dimming of its luminous flux. The possibility to merge the above-mentioned technical solutions is also analyzed. Based on these strategies, several daily schedules of lighting management are defined, and the corresponding energy saving during some critical time slots are assessed. Results show that in all cases, it is possible to achieve a significant reduction of the absorbed power and a consequent increment of energy savings (up to 59%) also in specific time ranges. Furthermore, considering the application of a Daylight-linked control system, it was observed that power regulation associated with the exploitation of the daylight represents itself a way to dynamically reduce the electric loads on the grid.

Sustainability of energy supply strategies in small islands has been emerging as a severe issue, due to the large margins for improvement and rationalization of the most frequently adopted solutions. In most of the European islands, large amounts of heat are wasted by the operation of engine-based power plants; conversely, heat is produced by boilers (supplied by liquid fuels) or by electric equipment for a number of different uses, like domestic hot water production or space heating in winter. In this paper a techno-economic analysis is proposed to assess the feasibility of CHP-retrofit of the existing power plants and the possible utilization of the recovered heat to supply, via a district heating and/or cooling network, the energy requests of civil energy users (both in the tertiary and in the residential sector). The analysis is accurately performed for six islands located in Italy and characterised by different context conditions from a demographic, geographic and climatic viewpoint, so as to get a comprehensive understanding of the factors that favour/obstruct the economic feasibility of the examined technical solution. As expected, due to the low “linear heat density” usually observed in small islands and to the complex orographic profiles, the investment usually resulted “far from being attractive”; only in the case where public incentive or support mechanism is adopted, the possible integration of the existing power plants with heat recovery devices and a district heating network resulted in moderately attractive, especially in the largest examined islands due to their highest heat loads.

In communities with a high tourist influx and warm climate, such as Mediterranean small islands, the energy demands for space cooling and domestic hot water are expected to significantly increase during summer. Considering the current energy context, for succeeding energy transition and reducing the dependency on not endogenous fossil fuels, it is paramount to increase the deployment of renewable sources of energy, especially wind and solar which, however, are aleatory and unpredictable. Hence, to reduce the high costs for energy supply in these contexts, the analysis of the variation of energy consumption is fundamental. Moreover, mapping the spatial distribution of energy profiles can be useful to have an overview at a large scale of the considered building stock. Within this frame, a Geographic-Information-System-based procedure was implemented to estimate the residential buildings energy demand profiles, focusing on the seasonal variation. The adopted method can provide a valid supporting tool for decision makers that have to implement smart energy strategies in contexts with a high variation of the energy demand and evident electricity summer peaks. The method for mapping the energy demand profiles, implemented on the small island of Pantelleria, can be applied to other similar contexts, also supporting energy policies in the implementation of renewable energy communities.