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Solar heating and cooling (SHC) systems can be relevant in the achievement of energy and climate European goals. The benefits of these technologies should be evaluated taking into account their life-cycle energy and environmental impacts, calculated by applying the Life Cycle Assessment (LCA). The development of a complete LCA can be difficult and time-consuming particularly for non-experts in LCA, discouraging them in developing the life-cycle assessments. To overcome this issue, the paper presents "ELISA - Environmental Lifecycle Impacts of Solar Air-conditioning systems", a user-friendly simplified tool for estimating the life-cycle energy and environmental benefits/impacts of solar technologies for heating and cooling in different geographic contexts and comparing them to conventional systems. The tool was applied to analyse three systems (thermal SHC, conventional and PV assisted system) in Greece and to identify the one characterized by the best life-cycle performances. The results revealed that the impacts of PV assisted system are about 60% lower than those of the others, highlighting the advantage of using renewable electricity for building air-conditioning in locations with high solar radiation availability. ELISA can be used by researchers, designers and decision-makers to introduce the life-cycle thinking in the early design phase of heating and cooling systems. • ELISA is a tool for developing a simplified LCA of solar heating and cooling technologies. • ELISA calculates the impacts of heating and cooling systems in a specific geographic context. • Three systems installed in Athens (Greece) are examined by combining ELISA with a simulation tool. • The PV assisted system is the best one in terms of life-cycle energy and environmental performance. [ABSTRACT FROM AUTHOR]

• An instrumented pilot borehole connected with a road thermal collector was realized. • Experimental data were used to calibrate a numerical and dynamic model of the plant. • First experimental results permitted to characterise the thermal properties of the unsaturated soil. • A comparison with a conventional geothermal plant demonstrates its feasibility and effectiveness. • 79% of the thermal energy produced by the collector can be recovered from the storage in the winter. The adoption of more efficient technologies that integrate renewable resources for heating buildings is a key action for increasing sustainability in the residential sector in the European Union. Borehole thermal energy storage and road thermal collector systems, which have mainly been integrated in colder countries to develop renewable systems, aimed at preventing the freezing of road surfaces in winter, could also be used in warmer countries to develop sustainable heating systems for buildings. In this experimental–numerical study, the possibility of integrating these two systems for the heating of buildings located in the Mediterranean region is investigated for the first time. To this end, a pilot plant was built at the facility test site of the University of Palermo, with the aim of demonstrating the possibility of storing solar energy in summer and recovering it in winter. A new method is proposed to characterize both the thermal conductivity and diffusivity of the different materials in the design phase of the plant. The results of simulations conducted with a validated numerical model show that the proposed system, characterized by an average annual collector efficiency of 10% and a seasonal storage efficiency of 80%, can reduce the length of borehole heat exchangers by about three times compared with a conventional geothermal heat pump plant. [ABSTRACT FROM AUTHOR]

The public buildings sector represents one of the most intensive items of EU energy consumption; the application of retrofit solutions in existing buildings is a crucial way to reduce its impact. To facilitate the knowledge of the energy performance of existing non-residential buildings and the choice of the more adequate actions, Public Administrations (PA) should have the availability of proper tools. Within the Italian project “POI 2007-13”, a database and a decision support tool, for easy use, even to a non-technical user, have been developed. A large set of data, obtained from the energy audits of 151 existing public buildings located in four regions of South Italy have been analysed, elaborated, and organised in a database. This was used to identify the best architectures of two ANNs and to train them. The first ANN provides the actual energy performance of any building; the second ANN assesses key economic indicators. A decision support tool, based on the use of these ANNs is conceived for a fast prediction of the energy performance of buildings and for a first selection of energy retrofit actions that can be applied. [ABSTRACT FROM AUTHOR]

The paper aims at exploring the performances of a compact Desiccant Evaporative Cooling system called “Freescoo” (Free Solar Cooling) in comparison to standard conventional technologies. The Freescoo – that aims at applications in the residential sector and in small office buildings and includes a photovoltaic–thermal system – is analyzed, its monitored performance discussed and reported: under cooling conditions an Energy Efficiency Ratio of 12.8 is calculated, that reaches 50.7 if also photovoltaic generation is considered. To assess the performance of the proposed system a Life Cycle Assessment study was performed to investigate the system covering all its life, from the production, going through its use and its disposal. Results are compared to those obtainable by standard conventional systems with comparable heating and cooling power outputs to further explore the performances of the system. The electricity consumption of the investigated solar cooling system proves to be equal to only the 5% of the equivalent conventional system having the same thermal output during a year. The production phase of the Freescoo shows a predominant role among the other life cycle steps, reaching a 95% share on the total for some indicators, such as human toxicity. If the life cycle phase of a conventional system is compared with the whole life cycle of the Freescoo system, the former would report many indicators values higher by 200% in comparison to the latter. If use of water is considered, although the Freescoo system would require 2590 l of fresh water during a year in comparison to none consumed by a conventional system, the higher water footprint of conventional systems would result in water uses higher by three times if compared to the Freescoo. [ABSTRACT FROM AUTHOR]

Life Cycle Assessment (LCA) is an effective methodology to assess the energy and environmental impacts of energy systems during their life cycle, including manufacturing, operation and end-of-life. The aim of the paper is the application of a simplified LCA tool, developed in the framework of the International Energy Agency Solar Heating and Cooling Task 48, for comparing different typologies of solar assisted heating and cooling systems. In detail, solar thermal heating and cooling systems located in Palermo (southern Italy) and in Zurich (Switzerland) were compared with conventional systems assisted by grid connected and stand-alone photovoltaic plants. A validation of the tool was also carried out by comparing the obtained results with those of in-depth LCA studies. The results showed that the best system configuration in Palermo is the conventional system assisted by a grid-connected photovoltaic plant. Its impact on global energy requirement is about 83.7% and 74.5% of the corresponding impact of the solar thermal heating and cooling and the conventional system assisted by a stand-alone photovoltaic system, respectively. Different considerations can be made for Zurich, where the solar heating and cooling system performs better than the others; it is characterized by a global energy requirement that is 85.3% and 81.2% of the grid-connected and stand-alone photovoltaic assisted conventional systems, respectively. A similar trend is traceable for the global warming potential indicator. The validation of the LCA tool proved it to be reliable since deviations with a detailed LCA of the same system are contained below a 5% difference in all the comparable systems. [ABSTRACT FROM AUTHOR]

Research on building-integrated solar thermal collectors is attracting increasingly more interest. Many efforts have been focused at the design level for obtaining specific building-orientated products, but there is a significant lack of standardised methods for evaluating how the efficiency of solar collectors changes when a wall is an integral part of the solar component itself. Generally speaking, experimental tests on integrated components are not easy to realise and are, in any case, expensive in terms of time and money. Physical and numerical methods can be utilised, but at the moment, there is no common approach. The present work addresses a method for the calculation of a building-integrated component performance curve by means of a finite element method model. The main idea is to exploit data measured for a simpler and non-integrated component, which are readily available, for validating and calibrating a more complex model in which the system is coupled with a building element. Simulation assumptions and outputs are designed to comply with the main standards utilised for defining solar collector performance curves. The proposed method proves that it may be a good way to assess the performance curves of building-integrated solar thermal collectors and that it is suitable for reducing test costs. The authors have also highlighted the measures that must be taken for the sample collector to better fit the BIST performance model. [ABSTRACT FROM AUTHOR]

Desiccant rotors are commonly used in large scale solar cooling open cycle applications. As is well known, adsorption heat sensibly reduces the dehumidification capacity of the desiccant material and results in lower system performance. The aim of this work is to describe an innovative solution that permits simultaneous mass and heat transfer. In particular, two components working with silica gel fixed beds were studied and compared. The first component is a simple packed bed containing silica gel grains. The second component is a fin and tube heat exchanger commonly used in several air conditioning applications wherein the spaces between the fins are filled with silica gel grains. In this case, the adsorption material is cooled through a recooling loop. For both solutions, results are presented in terms of dehumidification performances versus operation time, storage of adsorption capacity and energy required for the regeneration of the desiccant. [ABSTRACT FROM AUTHOR]

Existing street lighting systems, in most of South Italy cities, are often inefficient due to the obsolescence of lamps and luminaires and of ineffective light control systems unable to implement efficient on-off and dimming strategies. Energy efficiency improvement, in street lighting systems, is often one of the key actions to be adopted by Public Administration in their Sustainable Energy Action Plan in the framework of the “Covenant of Majors” activities. As a task of FACTOR 20 project, a set of planning options has been analysed and proposed. Particularly, street lighting efficiency projects have been studied for representative case studies. A detailed survey of the public lighting systems, in Comiso, allowed represent current performance figures such us installed power, luminance and illuminance levels in roads categories, electricity consumption, switching and dimming schedules. A project of system upgrade has been elaborated. To do this, many lighting simulations, energy and economic assessments in three scenarios have been performed. The obtained results show that high improvements of the lighting quality are foreseeable together with large energy and economic saving. An economic sensitivity analysis, has shown how the performance can change. The proposed methodology can be applied in many similar South Italy cities. [ABSTRACT FROM AUTHOR]

• The first review of electrical heat pumps assisted by natural gas is performed. • Many different layouts and control strategies were found. • In most of the analyzed case studies, a rule-based control strategy is assumed. • Researchers presented very heterogeneous key performance indicators. • Exhaustive environmental analyses are very rarely presented. 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 substitute 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. [ABSTRACT FROM AUTHOR]

Highlights: [•] LCA application to solar assisted H/C systems (with solar thermal or PV panels). [•] Assessment of primary energy consumption and greenhouse gases emission. [•] Final results very sensitive to climatic conditions and national electricity mix. [•] PV grid-connected plant performed better than the other systems. [•] Solar thermal systems performed best among the configurations comprising storages. [Copyright &y& Elsevier]

Abstract: When a building undergoes a retrofit project, the goal of assessing energy and environmental performances of retrofit actions is a complex matter. Building and its environment are complex systems in which all sub-systems are strongly interdependent and influence the overall efficiency performance. In the following paper, starting from a literature review of building life-cycle studies, the authors highlight that there is a strong interplay among all the phases of a building life-cycle, as each one can affect one or more of the others. In detail, starting from the results of a “cradle to grave” life cycle study of an existing Mediterranean single-family house, a set of retrofit actions voted to reduce the energy consumption during the operation is analysed. The proposed actions are addressed to improve the thermal performance of the building envelope and the energy efficiency of technical equipment. Performance assessment of these actions has been carried out not only considering the related effects on energy saving for building operation, but also taking into account other phases of the life cycles. In fact, these measures will cause an increase in the building embodied energy, which is the energy embedded in building materials, utilised in transportation and construction processes, in maintenance and demolition. Thus, a balance between the energy saving during operation and the avoided environmental benefits due to the other phases has been done. In particular, the embodied energy and the environmental impacts related to production, transportation and installation phases of the required material/components for retrofit implementation are assessed. In other terms, LCA allows to estimate the reduction of the operation energy and the increase of the embodied energy within the building life-cycle, and to understand whether the achieved energy benefits could be supported in a life cycle perspective or were overcome by the environmental burdens of the actions. [Copyright &y& Elsevier]

Abstract: Since July 2008, a Solar Desiccant Evaporative Cooling (DEC) system has been operating as a test plant at the solar laboratory of the Dipartimento di Energia (ex DREAM) of the University of Palermo. The system is composed of an air handling unit (AHU) designed for ventilation of the laboratory coupled with a radiant ceiling that provides most of the required sensible cooling/heating energy. Flat plate collectors deliver part of the regeneration heat of the desiccant wheel during the summertime and are used for space heating during the wintertime. The system was designed for high humidity loads because of the typical climate conditions at the site and the need to support a radiant ceiling for sensible cooling. A hybrid configuration was chosen that uses two auxiliary cooling coils fed by a conventional compression chiller. One coil is used for pre-dehumidification. The other coil controls the air temperature if the desired supply temperature cannot be reached through indirect evaporative cooling alone. A specific feature of the system is the use of the heat rejected by the chiller to preheat regeneration airflow. The plant was monitored continuously after installation and start up phases were completed. This paper presents instantaneous, daily and monthly energy performance indicators for five summer months and three winter months. Monthly results are also presented and elaborated upon according to a monitoring procedure developed in the framework of the International Energy Agency (IEA) Task 38 “Solar Air Conditioning and Refrigeration” of the Solar Heating and Cooling Programme. Seasonal performance indicators such as electric and thermal COP and primary energy savings for cooling and heating operation are presented. It was found that about half of the total cooling energy delivered by the AHU was covered by the DEC process. Primary energy savings in summer, in comparison to a conventional AHU, came up to nearly 50%. The recovery of the heat rejected by the refrigerator was found as a good solution, permitting to reduce solar collector area in the design phase. Finally, main issues arisen from plant monitoring and possible solutions to enhance its energy performances are discussed. [Copyright &y& Elsevier]

Abstract: The development of renewable energy technologies is a critical tool for reducing climate change and the reliance on fossil fuels. However, renewable energy technologies cannot be considered totally clean because they require energy consumption and have environmental impacts that cannot be neglected during their life cycle. In this paper, the life cycle assessment methodology was applied to assess resource use and other environmental burdens related to the entire life-cycle steps of a solar cooling plant. The investigated system works with an absorption chiller assisted by a solar plant. Two back-up configurations (hot back-up and cold back-up) were examined in two localities: Palermo (southern Italy) and Zurich (Switzerland). The benefits in terms of primary energy savings and greenhouse gases emission reduction were demonstrated by comparing the use of this innovative plant in substitution of a conventional one. Energy and CO2eq emission payback times and the energy return ratio of the system were calculated. For all the analysed configurations they ranged from 4 to 6years. A sensitivity analysis related to the calculation of the energy payback time was carried out to assess the influence of various system performance parameters on the payback index. The analysis stressed the following: [–] LCA of renewable energy technologies has to include a detailed analysis of the use phase to assess the benefits that arise from the energy produced by the system during its useful life and to obtain reliable and high-quality LCA results. [–] The use phase is responsible of about 70–90% of the energetic and environmental impacts of the plant life cycle. [–] The innovative plant has a lower environmental impact than the conventional plant. [–] The advantages of renewable energy technologies strongly depend on the climate of the installation site. [Copyright &y& Elsevier]

Abstract: This work concerns an innovative solar assisted desiccant and evaporative cooling (DEC) system for building air conditioning. In this system, air-to-air packaged wet heat exchangers are used to maximize the exploitation of the evaporative cooling potential associated with the exhaust air stream. The thermodynamic cycle is first theoretically described, and then an example of a real application is shown. The system presented is an experimental DEC system originally installed at the beginning of 2008 at the Solar Laboratory of the University of Palermo and recently modified and updated. These modifications have been implemented with the aim to foster some problems related to the conventional indirect evaporative process and to increase the overall performance of the process. Different energy performance figures, such as thermal and electrical COP, are presented and discussed. The obtained results are very positive, showing that DEC systems can benefit from the use of wet heat exchangers to efficiently cool the air stream after the adsorption process in the desiccant wheel without any change in moisture content. [Copyright &y& Elsevier]

Abstract: The paper presents the results of an energy and environmental assessment of a set of retrofit actions implemented in the framework of the EU Project “BRITA in PuBs” (Bringing Retrofit Innovation to Application in Public Buildings – no: TREN/04/FP6EN/S07.31038/503135). Outcomes arise from a life cycle approach focused on the following issues: (i) construction materials and components used during retrofits; (ii) main components of conventional and renewable energy systems; (iii) impacts related to the building construction, for the different elements and the whole building. The results are presented according to the data format of the Environmental Product Declaration. Synthetic indices, as energy and GWP payback times, and energy return ratio, are defined to better describe the energy and environmental performances of the actions. The project highlights the role of the life cycle approach for selecting the most effective options during the design and implementation of retrofit actions. [Copyright &y& Elsevier]

Though many studies concern the agro-food sector in the EU and Italy, and its environmental impacts, literature is quite lacking in works regarding LCA application on citrus products. This paper represents one of the first studies on the environmental impacts of citrus products in order to suggest feasible strategies and actions to improve their environmental performance. In particular, it is part of a research aimed to estimate environmental burdens associated with the production of the following citrus-based products: essential oil, natural juice and concentrated juice from oranges and lemons. The life cycle assessment of these products, published in a previous paper, had highlighted significant environmental issues in terms of energy consumption, associated CO2 emissions, and water consumption. Starting from such results the authors carry out an improvement analysis of the assessed production system, whereby sustainable scenarios for saving water and energy are proposed to reduce environmental burdens of the examined production system. In addition, a sensitivity analysis to estimate the effects of the chosen methods will be performed, giving data on the outcome of the study. Uncertainty related to allocation methods, secondary data sources, and initial assumptions on cultivation, transport modes, and waste management is analysed. The results of the performed analyses allow stating that every assessed eco-profile is differently influenced by the uncertainty study. Different assumptions on initial data and methods showed very sensible variations in the energy and environmental performances of the final products. Besides, the results show energy and environmental benefits that clearly state the improvement of the products eco-profile, by reusing purified water use for irrigation, using the railway mode for the delivery of final products, when possible, and adopting efficient technologies, as the mechanical vapour recompression, in the pasteurisation and concentration of juice. [Copyright &y& Elsevier]

Abstract: This paper presents a detailed analysis of the energy and economic performance of desiccant cooling systems (DEC) equipped with both single glazed standard air and hybrid photovoltaic/thermal (PV/t) collectors for applications in hot and humid climates. The use of ‘solar cogeneration’ by means of PV/t hybrid collectors enables the simultaneous production of electricity and heat, which can be directly used by desiccant air handling units, thereby making it possible to achieve very energy savings. The present work shows the results of detailed simulations conducted for a set of desiccant cooling systems operating without any heat storage. System performance was investigated through hourly simulations for different systems and load combinations. Three configurations of DEC systems were considered: standard DEC, DEC with an integrated heat pump and DEC with an enthalpy wheel. Two kinds of building occupations were considered: office and lecture room. Moreover, three configurations of solar-assisted air handling units (AHU) equipped with desiccant wheels were considered and compared with standard AHUs, focusing on achievable primary energy savings. The relationship between the solar collector’s area and the specific primary energy consumption for different system configurations and building occupation patterns is described. For both occupation patterns, sensitivity analysis on system performance was performed for different solar collector areas. Also, this work presents an economic assessment of the systems. The cost of conserved energy and the payback time were calculated, with and without public incentives for solar cooling systems. It is worth noting that the use of photovoltaics, and thus the exploitation of related available incentives in many European countries, could positively influence the spread of solar air cooling technologies (SAC). An outcome of this work is that SAC systems equipped with PV/t collectors are shown to have better performance in terms of primary energy saving than conventional systems fed by vapour compression chillers and coupled with PV cells. All SAC systems present good figures for primary energy consumption. The best performances are seen in systems with integrated heat pumps and small solar collector areas. The economics of these SAC systems at current equipment costs and energy prices are acceptable. They become more interesting in the case of public incentives of up to 30% of the investment cost (Simple Payback Time from 5 to 10years) and doubled energy prices. [Copyright &y& Elsevier]

Abstract: A Geographical Information System (GIS) supported methodology has been developed in order to assess the technical and economic potential of biomass exploitation for energy production in Sicily. The methodology was based on the use of agricultural, economic, climatic, and infrastructural data in a GIS. Data about land use, transportation facilities, urban cartography, regional territorial planning, terrain digital model, lithology, climatic types, and civil and industrial users have been stored in the GIS to define potential areas for gathering the residues coming from the pruning of olive groves, vineyards, and other agricultural crops, and to assess biomass available for energy cultivation. Further, it was possible to assess the potential of biodiesel production, supposing the cultivation of rapeseed in arable crop areas. For the biomass used for direct combustion purposes, the economic availability has been assessed assuming a price of the biomass and comparing it with other fuels. This assessment has shown the strong competitiveness of firewood in comparison with traditional fossil fuels when the collection system is implemented in an efficient way. Moreover, the economic potential of biodiesel was assessed considering the on-going financial regime for fuel. At the same time, the study has shown a significant competitiveness of the finished biomass (pellets), and good potential for a long-term development of this market. An important result was the determination of biofuel production potential in Sicily. An outcome of the study was to show the opportunities stemming from the harmonisation of Energy Policy with the Waste Management System and Rural Development Plan. [Copyright &y& Elsevier]

Abstract: The energy demand of the hotel sector of an Italian region is here utilized for hierarchizing, by means of an empirical method, efficient measures devoted to energy saving and reduction of CO2 emissions. Due to the large number of consumers present in the selected territorial area and the lack in detailed data, the energy demand assessment is here carried out by the analysis of a sample of representative consumers. A short set of indexes, referring to energy and environmental performances, are defined and calculated for different clusters of hotels, grouped on the basis of site characteristics, opening periods, number of beds, and building age. Such indexes are utilized to establish lists of actions with assigned priorities stemming from energy, environmental and economics issues. Energy planners and decision makers can easily use this approach for defining, implementing and monitoring energy efficiency as well as sustainability policies in the tourist sector of a given geographical area, starting from a limited set of data. The method has been proposed by authors within the assessment of the Sicilian Energy Masterplan. [Copyright &y& Elsevier]

Abstract: Renewable energy sources are often presented as “clean”. A more correct definition is that they are “cleaner” than ones based on fossil fuel conversion. When the energy consumption and the environmental impacts related to the plant''s life-cycle are considered, a more comprehensive assessment of these technologies can be carried out. This paper aims to evaluate the energy and the environmental performances of the electricity production of a wind farm. The impacts related to all the phases of the wind farm construction and operation have been compared to the environmental benefits due to the “green” electricity generation during its useful life. In other terms, the goal is to trace the ecoprofile of the production of 1kWh of electricity. A life cycle assessment (LCA) has been performed based on data related to an Italian wind farm: production and deliver of energy and raw materials, components manufacturing, transports, installation, maintenance, disassembly and disposal have been analysed. The attention focused to those life cycle steps generally neglected or not adequately investigated as installation, civil works and maintenance. The results can be assumed as representative of the Italian context and they can represent a further incentive to the diffusion of wind farms. In fact, the environmental performances of the wind farm have been compared to other power energy generation systems. The results showed a great environmental convenience of the inquired technology. [Copyright &y& Elsevier]

Abstract: The paper presents a life cycle assessment of a kenaf-fibre insulation board following the international standards of the ISO 14040 series. Each life-cycle step has been checked, from kenaf production and board manufacture by an Italian firm, to use and disposal. The aim is to assess the board eco-profile and to compare, on the basis of a life-cycle approach, the energy and environmental benefits and drawbacks related to its employment into a typical residential dwelling. A comparison among various insulating materials has been carried out. The study focuses also on processes and input materials which cause the main environmental impacts of the product, and points out critical issues and the life-cycle steps with the highest improvement potentials. [Copyright &y& Elsevier]

Abstract: The saving of primary energy from fossil fuels and the promotion of exploitation of renewable sources are two of the most relevant goals to be achieved in order to match the climate protection target fixed by the Kyoto Protocol in 1997. For Italy, the commitment is the reduction of the greenhouse emissions by 6.5% below 1990 levels over the commitment period 2008–2012. It requires the introduction of suitable political strategies and programmes aimed to establish a sustainable energy system together with the application of a set of actions either at national scale, either at regional one. This study presents the results of a survey in the context of the Regione Sicilia about the potential saving of primary energy and the reduction of greenhouse emissions, which should be allowed by local energy planning in the energy uses. An assessment of the specific costs per unit of saved energy and of avoided CO2eq emissions is presented for each of the actions of the Sicily Regional Energy Master Plan (REMP). The REMP proposal has been presented by the University of Palermo, Messina and Catania together with ITAE-CNR. It is up today under discussion and examination by the Regional Government. [Copyright &y& Elsevier]

It is generally well known that the reliability of Life Cycle Analysis (LCA) studies depends upon exact, complete and sharp input data that, unfortunately, are not always available. Furthermore, when available, the input data are affected by uncertainty whose importance is not always adequately taken into consideration.This paper describes the software F.A.L.C.A.D.E. (Fuzzy Approach to Life Cycle Analysis and Decision Environment): a tool designed for the calculation of the eco-profile of products, based on a fuzzy logic approach. The originality of the method already treated in other papers is to use the fuzzy representation to manage the complex relationships that arise in compiling an eco-balance. In particular, the model allows to give further attributes to the numerical data of the inventory based to the expert knowledge. The uncertainty of data is clearly defined by means of four fuzzy linguistic variables: the age of the data, the kind of technology to which data are referred to, the statistical and geographic representativeness of the data.The main model’s strength is transparency. Many LCA tools appear, unfortunately, as “black boxes” leaving the actual influence of the algorithms upon the final results unclear. On the other hand, with F.A.L.C.A.D.E. the user is able to observe and control all the calculation steps from the input of data to the final results. For instance, F.A.L.C.A.D.E. uses a linear sub-model that, starting from the inventory matrixes, allows to calculate an eco-profile together with a conditioning number “CN”, which describes how sensitive is the linear model to errors when solving the system of equations. Finally, the software present a set of tables summarising the results obtained with the fuzzy model. These results can be compared with those obtained with other methods. The software represents therefore a tool to evaluate the quality of Life Cycle Inventory (LCI) study.F.A.L.C.A.D.E. has been developed using an object-oriented programming. The result is a flexible tool whose structure can be easily changed by the user (variables, linguistic rules, domains of the fuzzy groups, etc.). As case study, the software has been applied to the LCA of a plaster material commonly used in building construction. [Copyright &y& Elsevier]

Solid oxide fuel cells (SOFC) could facilitate the green energy transition as they can produce high-temperature heat and electricity while emitting only water when supplied with hydrogen. Additionally, when operated with natural gas, these systems demonstrate higher thermoelectric efficiency compared to traditional microturbines or alternative engines. Within this context, although digitalisation has facilitated the acquisition of extensive data for precise modelling and optimal management of fuel cells, there remains a significant gap in developing digital twins that effectively achieve these objectives in real-world applications. Existing research predominantly focuses on the use of machine learning algorithms to predict the degradation of fuel cell components and to optimally design and theoretically operate these systems. In light of this, the presented study focuses on developing digital twin-oriented models that predict the efficiency of a commercial gas-fed solid oxide fuel cell under various operational conditions. This study uses data gathered from an experimental setup, which was employed to train various machine learning models, including artificial neural networks, random forests, and gradient boosting regressors. Preliminary findings demonstrate that the random forest model excels, achieving an R2 score exceeding 0.98 and a mean squared error of 0.14 in estimating electric efficiency. These outcomes could validate the potential of machine learning algorithms to support fuel cell integration into energy management systems capable of improving efficiency, pushing the transition towards sustainable energy solutions. [ABSTRACT FROM AUTHOR]

• The possibility to modulate the indoor artificial lighting in order to contribute to this reduction is explored. • The feasibility to change the Correlated Colour Temperature and the luminous flux is examined. • The impact of daylight-linked control systems is considered. • Modulable loads is advantageous to achieve an absorbed power decrease in a smart grid. • The application of the presented strategies can provide energy saving of up to 59%. 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. [ABSTRACT FROM AUTHOR]

Solar heating and cooling systems for space heating and cooling are experiencing a growing trend and interest. However, the actual energy and environmental performance of small/medium size installations is not clearly foreseeable. In this paper, an analysis of such systems using adsorption chillers in different European climates is presented. Solar systems have been simulated in TRNSYS and compared to a conventional system employing a vapour compression unit. The results have been used for a Life Cycle Assessment (LCA) study, determining the potential impact during the whole life of the system, from raw materials supply to its end-of-life. The LCA has been carried out by using the LCA tool developed in the framework of the International Energy Agency SHC Task 48. Results showed that the useful life of the system is a key parameter: for a useful life of 10 years, the conventional system performs better than the renewable-based one for almost all the locations. However, if a longer life is achieved (15 or 20 years), solar systems show environmental advantage under almost all the climatic conditions: the environmental benefits of using a solar system during the operation step counterbalance the additional impact generated during the other life-cycle steps. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• The energy performances of solar-assisted HP for DHW for DHW are studied. • Configuration of HP equipped with PV and PVT panels are investigated. • Solar systems sized to serve small aggregates are studied. • The energy consumption is mainly influenced by the required DHW demand per day. • PVT thermal contribution slightly influences the system performances. The paper investigates the energy performances of several configurations of solar-assisted heat pumps equipped with photovoltaic (PV) and photovoltaic-thermal (PVT) panels as well as solar thermal collectors for domestic hot water production. The systems are sized to serve small aggregates of users assumed as micro energy communities in low housing density context in the South of Italy. Electricity storages are also considered to smooth the interaction with the electric grid. Several indices are defined and calculated to guide toward a correct sizing, to check users' satisfaction and to assess primary energy savings. The results show how the energy consumption from the analysed systems is mainly influenced by the amount and structure of domestic hot water demand per day. Also, according to the chosen plant layouts, it is shown that thermal contribution of PVT slightly influences the system performances. Better results in terms of less non-renewable primary energy consumption are recorded for the PV-based plant. Solar thermal collectors, even if sized for high solar fractions, do not properly support the daily heat pump operation, especially in winter, and present a certain electricity consumption for auxiliaries which results to be penalizing. Additional calculations were performed for the case of energy communities in a context with higher uses of non-renewable energy for electricity generation. Finally, opportunities to support demand-response actions for grid electricity management were investigated. [ABSTRACT FROM AUTHOR]

In this paper, we present Overgrid, a fully distributed peer-to-peer (P2P) architecture designed to automatically control and implement distributed demand response (DR) schemes in a community of smart buildings with energy generation and storage capabilities. As overlay networks in communications establish logical links between peers regardless of the physical topology of the network, the Overgrid is able to apply some power balance criteria to its system of buildings, as they belong to a virtual microgrid, regardless of their physical location. We exploit an innovative distributed algorithm, called flow updating, for monitoring the power consumption of the buildings and the number of nodes in the network, proving its applicability in an Overgrid scenario with realistic power profiles and networks of up to 10 000 buildings. To quantify the energy balance capability of Overgrid, we first study the energy characteristics of several types of buildings in our university campus and in an industrial site to accurately provide some reference buildings models. Then, we classify the amount of “flexible” energy consumption, i.e., the quota that could be potentially exploited for DR programs. Finally, we validate Overgrid emulating a real P2P network of smart buildings behaving according to our reference models. The experimental results prove the feasibility of our approach. [ABSTRACT FROM AUTHOR]

The combination/integration of renewable energy and storage systems appears to have significant potential, achieving high-energy results with lower costs and emissions. One way to cover the thermal needs of a building is through solar energy and its seasonal storage in the ground. The SMARTEP project aims to create an experimental area that provides for the construction of a road solar thermal collector directly connected to a seasonal low-temperature geothermal storage with vertical boreholes. The storage can be connected to a ground-to-water heat pump for building acclimatization. This system will meet the requirements of visual impact and reduction of the occupied area. Nevertheless, several constraints related to the radiative properties of the surfaces and the lack of proper thermal insulation have to be addressed. The project includes the study of several configurations and suitable materials, the set-up of a dynamic simulation model and the construction of a small-scale road thermal collector. These phases allowed for an experimental area to be built. Thanks to careful investigation in the field, it will be possible to identify the characteristics and the best operation strategy to maximize the energy management of the whole system in the Mediterranean area. [ABSTRACT FROM AUTHOR]

The application of Building Automation and Control (BAC) systems has many advantages. One of these is the reduction of the end-user electricity consumption and, if applied to lighting systems, the achievement of well-acknowledged benefits from daylight, such as productivity, health, visual comfort and well-being. Concerning the first aspect, the international Standard EN 15232 proposes the so-called BAC Factors (BF) method to assess the impact of BAC systems on the final energy consumption. The method provides a simplified estimation of the energy savings due to automation in buildings and questions arise on its applicability in some situations. For this reason, the authors have carried out an experimental study aiming at comparing the energy savings calculated using the simplified BAC factor method with those evaluated with a measurement campaign on a laboratory setup. In particular, the BF are evaluated for an office and a residential environment, using sets of data measured in two cases study in South Italy by testing two lighting control systems in different end-uses (residential and office). The comparison between the sets of data shows the limits of the simplified BAC factor method. • The application of Building Automation and Control (BAC) systems has many recognized advantages. • BAC factors method was applied for a real daylight linked control system and evaluated for an office and a residential case. • Consumption calculated has been compared with consumption measured for a real case study. • The comparison between the two set of data shows the limits of the simplified BAC factor method. [ABSTRACT FROM AUTHOR]

Street lighting plays a crucial role in a city's night landscape and in urban traffic management, influencing users' comfort and safety. To contain costs of public street lighting systems and to avoid energy waste, illuminance levels on road surfaces must be adequate to fit actual traffic volumes, as prescribed by regulations. This is true not only for motorized roads but also for sidewalks, paths, and pedestrian areas. Regulations in force establish a relationship between road traffic volumes and minimum illuminance levels through the lighting classes selection procedure. Lighting classes selection is based on various para meters among which traffic volume is the most difficult to evaluate because traffic volumes are generally estimated or measured by a traffic observation campaign. In this paper, an alternative method for classes association which is based on a space syntax approach, is described. The method was applied to the case study town of Pontedera (Italy) for the analysis of the pedestrian and motorized traffic and it shows a good correlation between measured and estimated traffic volumes, demonstrating how the methodology, with a precise and quick estimation of traffic volumes, can help lead to a suitable design of the lighting infrastructure, aiming to reduce energy waste and to avoid oversized lighting systems. [ABSTRACT FROM AUTHOR]