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Before the COVID-19 pandemic, ventilation in buildings was not always given its due importance. The World Health Organization has highlighted the important role of air exchange with the outdoors in improving the air quality in buildings; buildings should, therefore, be equipped with mechanical ventilation or adequate air conditioning systems. This paper aims to investigate different retrofit solutions for air conditioning, evaluating them in terms of energy consumption and cost and the impact of increased outdoor air exchange rates on countering the propagation of COVID-19; the latter is the main novelty of the paper. As a case study, we take an existing office building located in Central Italy that was previously not equipped with a mechanical ventilation system (a system with primary air was introduced during the study). The energy analysis was conducted using dynamic simulation software after validation through energy bills; energy and economic analyses were conducted considering different external-air exchange rates. An optimal number of outdoor air changes was found to mitigate the risk of COVID-19 infection, a finding in line with the international literature. The increase in air changes with outdoor air leads to a rise in energy consumption and costs. These values were evaluated for different air conditioning systems and operational schedules. These drawbacks can be made less significant by combining interventions in the system with energy-efficiency measures applied to the building envelope. [ABSTRACT FROM AUTHOR]

The integration of renewable energy systems in buildings leads to a reduction in energy bills for end users and a reduction in the carbon footprint of such buildings, usually referred to as prosumers. In addition, the installation of charging points for the electric vehicles of people working or living in these buildings can further improve the energy efficiency of the whole system if innovative technologies, such as vehicle-to-building (V2B) technologies, are implemented. The aim of this paper is to present an Energy Management System (EMS) based on mathematical programming that has been developed to optimally manage a prosumer building equipped with photovoltaics, a micro wind turbine and several charging points for electric vehicles. Capabilities curves of renewable power plant inverters are modelled within the EMS, as well as the possibility to apply power curtailment and V2B. The use of V2B technology reduces the amount of electricity purchased from the public grid, while the use of smart inverters for the power plants allows zero reactive power to be drawn from the grid. Levelized cost of electricity (LCOE) is used to quantify curtailment costs, while penalties on reactive power absorption from the distribution network are evaluated in accordance with the current regulatory framework. Specifically, the model is applied to a prosumer building owned by the postal service in a large city in Italy. The paper reports the main results of the study and proposes a sensitivity analysis on the number of charging stations and vehicles, as well as on the consideration of different typical days characterized by different load and generation profiles. This paper also investigates how errors in forecasting energy production from renewable sources impact the optimal operation of the whole system. [ABSTRACT FROM AUTHOR]

The use of biomass can be a strategic way to realize a carbon-neutral energy plan, ensuring a fuel feedstock. Residual biomass arising from pruning is demonstrated to be an important energy resource in terms of quantity and quality. In the Salento peninsula, Apulia Region, in the south of Italy, a dramatic outbreak of Xylella fastidiosa has decimated olive trees since 2013, gaining a considerable amount of wood biomass. This paper, starting from the need to find a way to optimize the use of this available stock, reviews the main technologies on the utilization of olive wood for energy purposes. In particular, processes and products are here described, and an energy analysis compares lower heating value (LHV), higher heating value (HHV), mass yield, process operating conditions, and energy generated and spent by the process in order to find the most effective technology in order to optimize the energy use of olive biomass. The conclusions show the advantages and disadvantages of each technology. Pyrolysis performs well, showing the best results for both char HHV and syngas yield under different operating conditions. Gasification seems to be the most appropriate among conversion technologies to optimize olive tree pruning for energy purposes, as it can be used to produce both electrical and thermal energy. In terms of economic valorization, char is the most promising material representing a value-added product, the quality and versatility of which ranges from fuel to soil improvers and additives for the construction of supercapacitors. Conversely, its disadvantages are mainly represented by high ash content, which can slightly decrease the boiler efficiency. Finally, the amount of alkali metals can produce several problems, such as fouling, slagging, corrosion, etc., posing a challenge for combustion control and pollutant minimization. [ABSTRACT FROM AUTHOR]

The building and construction sector has a significant impact on the CO2 emissions and pollutants released into the atmosphere, which contribute to climate change. The EPDB Directive mandates the achievement of minimum energy class E for all residential buildings by 2030 and energy class D by 2033. Particularly, in Italy, about 86% of the existing building stock predates the enactment of any energy laws or regulations, making it imperative to apply the energy efficiency interventions. This paper provides a support decision tool for the identification of the standardized interventions in the building envelope, the air conditioning system, and domestic hot water production. This study is focused on a specific construction period class (1976–1990) in six different climatic zones. The methodological approach is based on a cataloguing phase and the definition of ante operam energy classes as well as on case study identification, energy requalification intervention identification, solution simulations, and cost estimation. By simulating the standardized interventions for each climatic zone, a range of possible combinations is identified. The most advantageous ones are determined based on a cost–benefit analysis considering the potential class jump achieved. The research result is a matrix of energy efficiency interventions that is applicable to each climatic zone and can be extended to the existing housing stock. [ABSTRACT FROM AUTHOR]

In the current context of joint efforts towards the decarbonisation of buildings, integrating occupants' comfort and health with latest technological advancements for energy efficiency is at the center of the latest development of research, policies and professional practice. Radiant systems are encountering great success since the low-thickness systems can also be used in renovation projects for both heating and cooling, while guaranteeing optimal comfort. However, dehumidification is often required for optimal radiant cooling operation with no condensation risks, and the great potential of mechanical ventilation systems to optimally address the needs for dehumidification, air renewal, health and energy efficiency appears to be far from its full exploitation in the post-COVID-19 era. The present paper aims at providing a quantification of the energy and financial impacts of the implementation of a controlled mechanical ventilation system (CMV) coupled to a radiant system in a typical residential case study building in Italy. The results show that the sole CMV may decrease primary energy demand and energy costs by more than 30% and contribute to an increase in the smart readiness of the building by 8%, but further incentive policies must be developed to cover the still high investment and maintenance cost. [ABSTRACT FROM AUTHOR]

In this paper, the research trend in relation to the NZEB buildings is explored, through the analysis of selected scientific articles published in 11 journals collected in chronological order from 2014 to 2020. The analysis is carried out on the basis and terms of annual investigative publications of the documents in relation to the NZEB, such as contributions made by countries, institutions, authors, and research topics covered. The study carried out uses a document review methodology. The analysis reveals a growing interest in energy efficiency research in recent times, implying that the importance that the construction industry attaches to NZEB in consequences of global warming and accelerating environmental problems. The findings also indicate that, during the period studied, researchers in developed economy areas such as the US and Italy contributed higher rates to promoting research on NZEB. Developing countries like China also went to great lengths to promote research. Research topics covered tend to focus on studies completed with NZEB project delivery and development, building rehabilitation, energy performance, and advanced technologies applied for energy improvement in buildings. This research provides a valuable platform for industry professionals and researchers to understand NZEB construction research trends and developments, including their applicability and their future research and contributions to the topic. [ABSTRACT FROM AUTHOR]

As the urgency to mitigate climate change intensifies, the achievement of zero carbon targets in the built environment has become a critical objective. Building retrofitting plays a vital role in reducing energy consumption and carbon emissions in existing buildings. This paper presents an approach that combines Building Information Modeling (BIM) with multiple domains to strive for zero carbon targets in building retrofit projects. The proposed approach is based on a dynamic multi-parameter analysis that integrates indoor comfort, energy savings, CO2eq reduction, and the social cost of carbon while considering investment costs. Renewable energy technologies, such as photovoltaic panels and solar thermal systems, are emphasized to achieve the desired zero-carbon outcomes. Real-time monitoring mechanisms enable continuous performance evaluation and adaptive retrofit strategies for further energy savings. This approach is validated through a case study of an existing thermal bath building, known as "Terme Lucane", located in southern Italy. The results of the study demonstrate significant reductions in energy consumption and carbon emissions, highlighting the potential of the proposed approach to achieve zero carbon targets through the integration of multi-data BIM implementation. These findings offer a promising pathway for building retrofit projects aiming for zero carbon targets through multi-data BIM modeling. [ABSTRACT FROM AUTHOR]

The Renovation Wave for Europe highlighted the role of the public building stock for which Directive 2012/27/EU has set an annual renewal rate of 3%, which should rise to reach the goal of decarbonization by 2050. In this paper, the energy retrofit of an educational building—at the academic level—in Southern Italy was investigated. The aim was to evaluate the incentive share, which could accelerate the energy efficiency process, to achieve a cost-effective nZEB. The results show that the highest incentive rate is required for interventions on the opaque building envelope, which are also those that allow the least energy savings. An incentive rate of about 45% for the energy efficiency of the transparent envelope is necessary to reduce the payback time by about 7 years. The efficiency of the plants and the installation of a PV system are energetically and economically convenient even without forms of economic incentive. Finally, if the building is brought to high energy standards—a primary energy saving of 46% and energy class A3—an incentive rate of 40% is required to repay the intervention in about 10 years. [ABSTRACT FROM AUTHOR]

Increasing interest in natural gas-fired gensets is motivated by District Heating (DH) network applications, especially in urban areas. Even if they represent customary solutions, when used in DH, duty regimes are driven by network thermal energy demands resulting in discontinuous operation, which affects their remaining useful life. As such, the attention on effective condition-based maintenance has gained momentum. In this paper, a novel unsupervised anomaly detection framework is proposed for gensets in DH networks based on Supervisory Control And Data Acquisition (SCADA) data. The framework relies on multivariate Machine-Learning (ML) regression models trained with a Leave-One-Out Cross-Validation method. Model residuals generated during the testing phase are then post-processed with a sliding threshold approach based on a rolling average. This methodology is tested against nine major failures that occurred on the gas genset installed in the Aosta DH plant in Italy. The results show that the proposed framework successfully detects anomalies and anticipates SCADA alarms related to unscheduled downtime. [ABSTRACT FROM AUTHOR]

Hydraulic complexity metrics referred to as M1 and M2 play an important role when it comes to the analysis of habitat metrics. In the present paper, the significance of these parameters is analysed by using laboratory data as well as field observations along the Tiber River in Italy. Based on the laboratory data, the estimated parameters allow us to characterise the high/low-velocity areas. Based on field observations, larger magnitudes of M1 are linked to the zones with large changes in cross-sectional flow velocity. Larger magnitudes of M2 are observed at the left bank of the channel for all flow conditions, suggesting locations with larger kinetic energy consumption for aquatic organisms. Overall, the findings of the present research would be of particular interest in quantifying biologically important flow patterns occurring at different spatial scales within different streams and flow conditions. [ABSTRACT FROM AUTHOR]

Green hydrogen exploitation plays a crucial role in achieving carbon neutrality by 2050. Hydrogen, in fact, provides a number of key benefits for the energy system, due to its integrability with other clean technologies for energy production and consumption. This paper is aimed at presenting the project of recovery of an abandoned industrial area located in central Italy by developing a site for the production of green hydrogen. To this aim, the analysis of the territorial and industrial context of the area allowed us to design the project phases and to define the sizing criteria of the hydrogen production plant. The results of a preliminary cost–benefit analysis show that a huge initial investment is required and that, in the short term, the project is sustainable only with a very large public grant. On the other hand, in the long term, the project is sustainable, and the benefits significantly overcome the costs. [ABSTRACT FROM AUTHOR]

Market-based instruments such as white certificates offer the potential to increase efficiency gains, reduce primary energy consumption and make energy systems more resilient. The purpose of this paper is to provide insights into the white certificate scheme through a case study analysis. In light of increasing decarbonization and energy efficiency targets, it is important to rethink the role that policy instruments play in the energy transition, including the energy efficiency obligation schemes within which white certificate schemes fall. We focus on Italy's white certificate scheme because it is among the longest-lived and has achieved notable results. The scheme is characterized by annually increasing energy savings targets, flexibility, the opportunity to include many interventions, and the role of energy services companies. We provide evidence based on an empirical survey and fill the research gap left by the latest updates to the scheme along with an appraisal of those updates, which covers prominent scheme innovations such as its stability mechanism. Our research can serve as a baseline for policymakers in designing white certificate schemes in countries with little related previous experience and provide useful information from countries where similar schemes have been implemented to fine-tune similar market-based mechanisms to improve energy efficiency. [ABSTRACT FROM AUTHOR]

The paper deals with the energy transition, focusing on the decisions to be taken about the change in the energy conversion capacity of specified portion of the universe, such as industrial or domestic districts, regions, countries, etc. Conversion capacity is intended here as the set of all energy conversion and storage units characterized by type, size and number, and interacting with the natural gas and electricity grids. The goal is to find guidelines for new installations, obtained by simulations of a model able to describe properly the behavior of each energy conversion technology and the interaction with grids. The model is based on a traditional MILNP approach, but contains unique features in the literature, which allow to obtain results of general validity for applications to very different geographical areas, or to countries including very different regions that transmit energy with each other or export/import it from abroad. The main novelty of this work is to identify the best planning for the decarbonisation of energy demand sectors, according to the criterion of minimum cost, both at global and at regional level. The results applied to the case of Italy allow identifying clearly the energy demand sectors to which new installations should be applied first to minimize the cost for the total energy system, and the units that must be foreseen to satisfy these energy demands, i.e. a precise strategy for the energy transition towards a 100% renewable system. • A multi-regional model is built to find the most convenient energy transition path. • General guidelines for Western countries are derived from the Italian case study. • Replacement of boilers with heat pumps allows increasing RES share from 20 to 30%. • For RES share >60%, PtG is the low-carbon strategy for high temperature heat demand. • Transportation is the last energy sector that should be decarbonized. [ABSTRACT FROM AUTHOR]

The European Union has been allocating funds for the energy transition to meet escalating global energy demands while minimising the environmental impact. This paper focuses on the impact of post-pandemic policies on photovoltaic technology in Italy and Portugal, specifically analysing self-consumption schemes and energy communities. A techno-economic assessment identified optimal PV systems for four families in each country, considering financial incentives. Italy offers Superbonus 110 and Ecobonus schemes, while Portugal provides access to the Environmental Fund. Profitable PV systems with storage are feasible in Italy but not in Portugal. Superbonus 110 favours smaller systems, Ecobonus supports larger ones, and Portuguese policies prioritise smaller systems. Simulations of energy communities for the same families showed that in Italy, the best configurations consist of families acting as producers with larger PV capacities and smaller batteries. In contrast, in Portugal, the policies favour smaller PV systems without batteries, resulting in optimal configurations where families are solely consumers. This research underscores diverse national approaches to post-pandemic energy policies and their nuanced impacts on PV technology in Italy and Portugal. It can be concluded that energy communities offer greater profitability than individual self-consumption schemes. This is because individual households continue to prioritise self-consumption and personal savings while selling their excess energy at a more favourable price than what they would receive from the grid. • In Italy, there are financial incentives and in Portugal, electricity cost reductions. • The models used the Net Present Value and the Internal Rate of Return as indicators. • In Italy, Superbonus 100 favours smaller systems, while Ecobonus supports larger ones. • Smaller systems without batteries for self-consumption are more profitable in Portugal. • Energy communities are more economically viable in both countries. [ABSTRACT FROM AUTHOR]

This paper studies the influence of temperature and of rainfall intensity and the effect of such variations on the treatment efficiencies and on the electrical consumptions in seven medium-large size Wastewater Treatment Plants (WWTPs) in Apulia in South Italy (Bari, Barletta, Brindisi, Lecce, Foggia, Andria and Taranto). It has been observed, in the considered WWTPs, a slight but clear increase of the incoming flow due to the increase in rainfall intensity, which results to an increase of the energy consumption per incoming volume. The impact of the climate change to the incoming flow, during the last five years (2016–2020), has been assessed indicating that an increase in rainfall intensity results to an increase of the WWTPs energy consumptions per wastewater treated volume. More specifically, for a specific WWTP (Lecce) it was found that the electrical consumption increases from 0.36 kw/m3 to 0.51 kw/m3 when the rainfall intensity was increased from 0.8 mm/min to 2.9 mm/min. Some adaption measures have been considered to upgrade the existing WWTP so to mitigate the energy increase and to limit the global effects of climate change. [Display omitted] • As Rain intensity rises, wastewater influx into WWTPs increases. • Rainfall intensity influences negatively electrical consumptions. • BOD removal is lower with increasing annual precipitations. • Temperature influences BOD, COD and SST removal efficiency. [ABSTRACT FROM AUTHOR]

Energy retrofitting of residential buildings is considered a challenge to be tackled not only at building level, but also at urban scale, to give a stronger impulse for a concrete transition towards climate neutrality. This paper presents an easy-to-use analysis method based on the elaboration and scaling-up of data collected through the energy performance certificates (EPCs) to identify different urban energy zones distinguished by their energy performance index. This method is therefore conceived for better informing urban planning decisions, thus boosting more effective energy-sensitive urban planning strategies and eventually to foresee dedicated financial instruments to act in the more energy demanding areas of the city, establishing priorities for integrated strategies. This analytical method has been applied and tested in one municipality in the Emilia-Romagna region, Italy, where the recent urban planning law is pushing municipalities towards the development of urban planning strategies oriented to drastically improve the energy efficiency of the existing building stock. Results show that only a small number of areas manage to reach a good performance with fairly low levels of energy performance index, with the most critical situation found in the most central areas of the capital and in the hamlets. • Easy-to-use method for assessing energy performance of residential building at urban scale is proposed • Method based on data easily available for local authorities, like energy performance certificates (EPCs) and urban morphology • The method supports urban planners in municipalities in taking more targeted decisions for improving energy efficiency • The main output of the method is the definition of an energy performance index (EPI) for different urban contexts • EPI allows to wisely balance economic incentives, identifying areas where multi-purpose interventions are recommended [ABSTRACT FROM AUTHOR]

Abstract Industry is one of the highest energy consumption sector: some facilities like steelworks, foundries, or paper mills are highly energy-intensive activities. Many countries have already implemented subsidies on energy efficiency in generation and utilisation, with the aim of decreasing overall consumption and energy intensity of gross domestic product. Meanwhile, researchers have increased interest into alternative energy systems to decrease pollution and use of fossil fuels. Hydrogen, in particular, is proposed as a clean alternative energy vector, as it can be used as energy storage mean or to replace fossil fuels, e.g. for transport. This work analyses the re-vamping of the energy generation system of a paper mill by means of reversible solid oxide cells (RSOCs). The aim is not only to increase efficiency on energy generation, but also to create a polygeneration system where hydrogen is produced. Application on a real industrial facility, based in Italy with a production capacity of 60000 t/y of paper, is analysed. First, the current energy system is studied. Then, a novel system based on RSOC is proposed. Each component of the systems (both existing and novel) is defined using operational data, technical datasheet, or models defined with thermodynamic tools. Then, the interaction between them is studied. Primary energy analysis on the novel system is performed, and saving with respect to the current configuration is evaluated. Even if the complexity of the system increases, results show that saving occurs between 2 and 6%. Hydrogen generation is assessed, comparing the RSOC integrated system with proton exchange membrane (PEM) electrolysis, in terms of both primary energy and economics. Results exhibit significant primary energy and good economic performance on hydrogen production with the novel system proposed (hydrogen cost decreases from 10 €/kg to at least 8 €/kg). Highlights • The re-vamping of the energy generation system of a paper mill is analysed. • Reversible solid oxide cells are used increasing efficiency on energy generation. • A polygeneration system where hydrogen is produced is also created. • Primary energy saving on energy facility generation occurs between 2 and 6%. • Significant primary energy and good economic performance on hydrogen production are performed. [ABSTRACT FROM AUTHOR]

Abstract Energy efficiency, which is one of the pillars of the EU's Energy Union strategy, has been proposed as a solution, namely as a highly effective pathway to improve economic competitiveness and sustainability of the European economy, lower emissions, reduce energy dependency and increase security of supply, and job creation. The paper reviews the EU strategies and policies on energy efficiency and argues that further focus should be placed on industrial energy efficiency. Despite a decline in energy consumption in recent years in industry, this sector is one of the largest users of energy in the EU. Therefore, the paper reviews the extent to which the European and national policies in the selected jurisdictions, such as Italy and the UK address energy efficiency in industry and whether there are any measures in place to promote it. Highlights • Legal certainty is required in industrial energy efficiency policies. • White Certificates play a major role in industrial energy efficiency in Italy. • Yet, constant changes in the WC regulations can act as an investment barrier. • The UK's Energy Efficiency policy is underpinned with decarbonisation of the industry. [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]

The building sector plays a crucial role in the advocated transition towards a carbon-free economy, and thus the zero-carbon building concept is taking hold. The paper focuses on the issue of existing hotels, with the aim of investigating the possibility of meeting the ambitious zero-carbon targets for this category of buildings, in which guests' comfort and satisfaction is the core business. A reference hotel and different retrofit scenarios are assessed in two Italian climatic zones. Models are evaluated with a multi-objective approach, by introducing a set of hotel-related Key Performance Indicators (KPIs), to evaluate the simulated models on three main dimensions: thermal comfort, energy and environmental impacts. The obtained results have emphasized the difficulty to achieve the zero-carbon targets, due to the high energy consumptions caused by the comfort-based nature of hotels and of the space constraints for on-site renewable sources. These outcomes help highlighting the need to shift the focus from single building to district or city scale, proving that the zero-carbon building definition must go hand-in-hand with the Post-Carbon City concept. • Transforming the built environment is fundamental to realize the Post-Carbon City. • Retrofit scenarios for an Italian Reference Hotel are modelled using EnergyPlus. • Scenarios are evaluated through multi-dimensional Key Performance Indicators. • Zero-carbon targets are still not tailored enough for comfort-based buildings. • A shift from building to district/city scale is needed to reach zero-carbon targets. [ABSTRACT FROM AUTHOR]

Italy has reconsidered incentives on Renewable Energy Sources (RES) to implement the EU clean energy transition and Renewable Energy Communities (REC). Legislation on RECs shifted the focus of incentives from production to self-consumptions. In this paper, the REC model is studied in a minor island disconnected from the national grid, with strongly seasonal energy load and water demand. This is a typical Mediterranean scenario where energy demand is covered by Diesel gensets and water supply is provided with tankers. The implementation of RES is investigated, exploiting the current REC model of incentives. Two sub-optimal REC configurations were defined using time-dependent simulations on pyRES, an in-house code for energy systems. Results show the economical unfeasibility of REC when there is a poor mix of users. In contrast, REC can achieve economic profitability including industrial demand of a desalination unit (DES). The increase of self-consumption guaranteed from the DES allows to increase the NPV of the community and results in major cuts in CO 2 emissions (60% of those related to water supply and 10% of those from Diesel gensets) and a reduction of fuel costs of 22%. This method can be applied to investigate the performance of a REC in a local environment and help stakeholders in planning the expansions of RECs on the territory. [ABSTRACT FROM AUTHOR]

Although it is widely accepted that renewable energy consumption is vital for environmental sustainability, the environmental effectiveness of individual renewable energy types is often overlooked. Therefore, this paper examined the multivariate relationship between disaggregated renewable energy (hydroelectricity, wind, solar and biomass) consumption, economic growth and environmental pollution for the period from 1991 to 2014 in G-7 (The Group of Seven) countries. The study used both augmented mean group estimator and panel bootstrap causality method to consider the cross-sectional dependence and country specific heterogeneity across G-7 countries. Empirical findings indicate that increasing biomass energy consumption was efficient to reduce carbon emission in France, Germany, Japan and the United States; increasing hydroelectricity usage was efficient to reduce carbon emission in Italy and the United Kingdom; wind energy consumption reduced emission in Canada and solar energy usage was efficient on reducing emission in France and Italy for observed period. Moreover, in case of panel, it is found that increasing hydroelectricity, biomass and wind energy consumption reduced carbon emissions while the impact of solar energy consumption is statistically insignificant in G-7 countries. In addition, the hydroelectricity consumption was found the most efficient renewable energy source to reduce environmental pollution for the panel of G-7 countries. • Disaggregated renewable usage consumption and carbon emission nexus is investigated. • Increasing hydroelectricity usage reduces emission in Italy, the UK and the US. • Increasing wind energy usage reduces emission in all G-7 countries excluding Japan. • The effect of solar energy consumption on emissions is statistically insignificant. [ABSTRACT FROM AUTHOR]

Idling is a status of tractors in which the engine is not subjected to any substantial load and the vehicle is stationary. Idling is detrimental for the environment and health of people and it is a frequent status for agricultural tractors. Indeed, agricultural tractors may idle from 10 to 43% of their entire operating time. Only in some conditions idling is necessary (e.g. implement hitching), otherwise it is a condition which wastes fuel. The aim of this paper is to report on an updated methodology to analyse the idling practice of agricultural tractors. Idling was monitored through a dash-cam and a CAN-Bus data logger installed on a tractor with a maximum engine power of 191 kW. The tractor ran on idle for 17% of its entire operating time with the most frequent stops occurring for the adjustment of the implement when the soil engaging tools become clogged by crop residuals. Moreover, during 67% of the idling duration, no tractor subsystem was used, so most of the idling was not caused by a real need. This idling was responsible for a waste of 1.6% of the fuel used. Considering that in Italy 8.3% of the tractors belong to the same class (in terms of mass) of that used in this study, 43 million of litres of fuel are supposed to be wasted per year. The results of this study could be used for developing anti-idling devices on agricultural tractors. • Tractors stop for idling more often and for a shorter time than heavy-duty trucks. • In 67% of idling, the three-point hitch or auxiliary valves were not used. • 1.6% of fuel used was wasted in idling stops where any subsystem was used. [ABSTRACT FROM AUTHOR]

Among the various heating technologies that can be applied to urban areas district heating is recognized to allow significant reduction in primary energy consumption, provided that the system is properly designed and operated. Thermo-fluid dynamic simulation tools can be of extreme importance in order to achieve this objective. This paper aims at presenting a thermo fluid dynamic model for the detailed simulation of large district heating network and showing how it can be usefully applied to examine options for the reduction of primary energy consumption. The model is tested using experimental data and then applied for analyzing transient operations of the Turin district heating network, which is the largest network in Italy and one of the largest in Europe. A comparison between simulations and experimental results shows that the model is able to predict the temperature in the nodes of the network with good accuracy. The thermal power required to each plant is also calculated with a good level of accuracy. The model can be used for the simulation of operational strategies, thus representing a versatile and important tool for the implementation of advanced management such as the installation of local storage units or the variation of user request schedules. • A thermo-fluid dynamic model for the detailed simulation of large DHNs is proposed. • The model receives data from the substations as the input. • The transient simulation of the Turin DHN is compared with measurements. • The model can be applied to implement advanced management strategies. [ABSTRACT FROM AUTHOR]

In Italy, the economic support scheme for high-efficiency cogeneration annually provides tradable White Certificates to new constructed or refurbished high-efficiency cogeneration plants over a period of 10 years, proportionally to their annual primary energy saving. In contrast to the legislation currently in force, which assumes the power grid efficiency constant, this paper aims at assessing the adoption of a time-dependent approach, based on the use of the thermoelectric-based power grid efficiency, for evaluating the primary energy saving ensured by high-efficiency cogeneration as well as the relating economic incentives. The case study being analysed includes two 5.5 kW el micro-cogenerators installed in Naples (South Italy). Beyond the conventional, three scenarios have been outlined, depending on the time accuracy adopted (yearly, monthly and hourly basis). Starting from 2016, the scenarios have been replicated over the ten-year incentive period. In particular, the annual average thermoelectric-based power grid efficiency has been forecasted from 2021 to 2025. Following the innovative approach proposed in this study, the White Certificates would have increased by 9.2% in 2016, by 6.1% in 2017 and by 6.1% in 2018 too, thus fostering the achievement of the targets about high-efficiency cogeneration at national level. • In Italy, White Certificates are recognized to high-efficiency cogeneration. • The power grid efficiency affects the primary energy saving of cogeneration. • Hourly thermoelectric-based power grid efficiency indicators vary over time. • Increased time-accuracy means improved meaningfulness of results. [ABSTRACT FROM AUTHOR]

To promote energy saving in the residential sector Directive 2012/27/EU has set the obligation for buildings supplied by central heating sources to install individual heat metering and accounting systems. However, in social housing, bills based exclusively on individual consumption should be unfair due to some unfavourable situations, such as first and top floors, presence of unheated common spaces, north oriented dwellings. Nevertheless, fair heat accounting rules should be introduced especially in social housing buildings, which are often thermally underperforming with inefficient heating plants and tenants are commonly low-income people and elderly. On the other hand, common regulations for heat accounting providing compensation to avoid inequalities among tenants have not been set and different approaches on this topic are present among EU Member States. In this paper the authors present a new heat accounting method for social housing based on the estimation of extra-consumptions due to building inefficiencies. According to this method, extra-consumptions are charged to all tenants in order to encourage energy efficient retrofit interventions. Finally, the new method has been experimented in a typical social housing building in Italy and compared to other methods applicable in EU, evidencing some advantages and weaknesses. [ABSTRACT FROM AUTHOR]

The construction sector contributes to 8% of carbon dioxide emissions, most of them caused by clinker production: in recent years, the efforts to reduce environmental impacts are growing. This paper investigates the environmental performances of clinker production and the factors driving emissions. For this purpose, the environmental impacts of 41 different grey clinkers produced in Italy from 2016 to 2021 certified by a third party according to the European standard EN 15804 have been assessed. Three input datasets (i.e., energy consumption, raw materials, and transport) have been investigated to identify the most significant variables that affected the environmental impact categories in the period 2016–2020: a stepwise regression allowed the identification of the optimal predictors to be included in the multiple regression models. The most significant variables are pet coke, fossil fuels, natural raw materials, and lorry transport. The identified models have been validated having regard to 2021 data. Therefore, for each impact category, multiple positive and negative dependencies which bear an effect on the environmental results have been quantified. The output provides proven quantitative results that can support cement producers to develop low-impacting clinker recipes. [ABSTRACT FROM AUTHOR]

This paper deals with the power conversion system architectures to interface a stationary electrochemical storage installation with the network. Theoretical justifications about the conversion system layouts and control, used for actual Italian installations, are given. This paper aims at giving the power energy society an overview of actual possibilities of static conversion of d.c. battery sources. [ABSTRACT FROM AUTHOR]

This paper aims to critically examine the issue of rendering historic buildings energy efficient. Although this subject has been discussed to some extent on the national and international levels, it largely has been under-theorised as the existing literature focuses mainly on technical matters related to the improvement of energy performance. Indeed, one of the main issues which has not been thoroughly addressed in the literature is balancing conservation needs on the one hand and improved energy performance of historic buildings on the other, partly due to improper analytical tools, methods, and parameters that are commonly used to classify the energy behaviour of historic buildings. It is the matter of insufficient existing tools which triggered the development of this paper. This paper is based on experimental measurements in order to determine the most relevant parameters and the average thermo-physical data of the historic building envelope. The experiments were followed by evaluation of the energy performance of three listed buildings in Italy using static (used for energy certification in Italy), semi- dynamic, and dynamic computer simulations, in order to understand which energy audit schemes best simulate the actual energy performance of historic buildings while identifying the strengths and limitations of each type of software. The simulations were carried out using experimental data on the thermo-physical parameters of the building envelope components, energy bills, temperature, and relative humidity of air. The ultimate goal was to define the appropriate intervention for 'particular' types of historic buildings, in order to optimise the energy-efficiency requirements along with preservation of their inherent cultural values. [ABSTRACT FROM AUTHOR]

The development of multigeneration systems is evolving in different directions. One of the main directions is the extended application of the technologies at smaller sizes. Micro-multigeneration solutions aim at becoming competitive at the size of the residential users. The cost of the technologies, in particular the cost of the cogenerator, is a major limitation to the diffusion of micro-multigeneration, especially in countries (e.g., Italy) where residential customers have a limited usage of electricity to supply their facilities. This paper discusses the prospects for the application of micro-multigeneration in Italy. The modelling and analysis of a residential micro-multigeneration system are developed from the energy efficiency and economic assessment viewpoints. The analysis is carried out on a typical system composed of a natural gas internal combustion engine, a small-scale photovoltaic plant, a backup boiler, thermal energy storage and electrical energy storage. A specific analysis tool has been implemented to address the operational planning of this system during a time period of one year. The whole model has been constructed from real data of thermal and electrical demand in a housing complex in Italy. The annual running cost and the primary energy savings occurring to serve the multi-energy demand have been considered in the operational assessment. From an economical viewpoint, the model considers the price of natural gas related to the cogeneration system, the electricity prices and all the tax breaks allowed in Italy. In this way, different scenarios have been constructed and assessed. The results indicate the impact of providing incentives on the purchase cost of the technologies, leading to increase the diffusion of micro-multigeneration solutions for the residential sector in the next years. [ABSTRACT FROM AUTHOR]

The paper aims to analyse and compare the environmental performances of the most widely used cooking appliances (the induction hob vs. the gas hob) considering a typical Italian scenario in terms of food, family and social habits. Cooking appliances are subject to energy labelling, and they represent the most impacting system inside households. This study was performed in accordance with the international standard, ISO 14040/14044, by using an attributional Life Cycle Assessment (aLCA). The functional unit is defined as the “preparation of a complete homemade meal (lunch) for 20 years consumed by a four-member family in Italy”. This study shows the dominance, in terms of environmental impact, of the induction hob with respect to the gas hob for most of the selected midpoint indicators. In particular, the induction hob accounts for more than 60% of the climate change and ozone depletion impact categories and more than 70% of the metal depletion category. The same trend is also noticed in the end-point categories (human health, ecosystem qualities and resources) and for the Cumulative Energy Demand indicator. Based on the experimental evidence of this work, the use phase is the most important due to the different energy carriers (natural gas vs. electrical energy). This finding is the result of the nature of the energy carrier (the electricity grid mix) in the Italian scenario, which is mainly based on non-renewable sources. In addition, concerning the production phase of the two appliances, the induction hob shows a relevant dominance in terms of the human toxicity and metal depletion impact categories due to the use of rare metals and coppers in the cooktop part manufacturing. The outcomes obtained from this study may be used by household manufacturers to improve the performance and design solutions of their appliances as well as by end users in their selection of cooking technologies. [ABSTRACT FROM AUTHOR]

The availability of reliable and up-to-date data on energy uses and consumption is a key aspect in order to achieve the goals set out by European Directives on energy efficiency, and to monitor the effectiveness of energy policies supporting buildings' retrofit actions. In such a context, a numerical model, implemented in Excel' and Matlab', was developed in order to determine the energy consumption for space heating, domestic hot water and cooking in households, based on a statistical dataset of 20,000 records collected in a survey on the energy consumption of Italian families carried out by the National Institute of Statistics (ISTAT). The space heating model is based on the definition of classes of dwelling-types, while the energy use for DHW and cooking are calculated on a record-by-record basis according to a Standard-based approach. The present paper presents the results of a refined version of the model, in particular the calibration of relevant parameters accounted for the secondary equipment for space heating, resulting in improvements in the reliability for the allocation of the fuel consumption among the end-uses. The refinement and validation of the model are still in progress, since they are functional for the assessment of the energy consumption of households in the period between two subsequent surveys. [ABSTRACT FROM AUTHOR]

Energy demand represents a global challenge that calls for innovative energy solutions. Road lighting contributes in a small part to the overall worldwide electricity consumption, however the possibilities for energy saving are numerous. The road lighting should provide the required lighting quality, in the most energy efficient way as possible. In this paper the Authors analyze, compare and discuss the numerical indicators currently used to evaluate the lighting and the energy performance of new-designed and existing road lighting systems. To support the discussion, the use of the case study of road lighting of the historic town center of Pisa is proposed. For the case study the Authors have chosen a significant sample of 20 roads representative of 80 similar roads located in the historic town center. For the sample, geometric surveys, luminance and illuminance measurements, calculation of the national and international energy performance indicators have been carry out. The considerations made by the Authors, obtained with an investigation procedure of general validity, are useful to point out strengths and weaknesses of each indicator and to provide suggestions on the use of the appropriate indicators during the design stage of road lighting systems. [ABSTRACT FROM AUTHOR]

In this paper a thermoeconomic analysis of a novel hybrid Renewable Polygeneration System connected to a district heating and cooling network is presented. The plant is powered simultaneously by solar and geothermal sources, producing electricity, desalinated water, heat and cooling energy. System layout includes Parabolic Through Collector (PTC) field, geothermal wells, Organic Rankine Cycle (ORC) unit and a Multi-Effect Desalination (MED) system. Cooling and thermal demands are calculated by suitable building dynamic simulation models, calibrated for Pantelleria Island. Electrical demand is obtained by measured data. A detailed control strategy has been implemented in order to prevent any heat dissipation, to match the appropriate operating temperature levels in each component, to avoid a too low temperature of geothermal fluid reinjected in the wells and to manage the priority of space heating and cooling process. A 1-year dynamic simulation has been performed and results analyzed on daily, monthly and yearly basis. The system achieved an SPB equal to 8.50 and it resulted capable to cover the energy demands of a small community. Moreover, the plant is capable to cover the fresh water demand of the Pantelleria Island. [ABSTRACT FROM AUTHOR]

Food industry is the production sector with the highest energy consumption. In Europe, the energy used to produce food accounts for 26% of total energy consumption. Over 28% is used in industrial processes. Recently, European food companies have increased their efforts to make their production processes more sustainable, also by giving preference to the use of renewable energy sources. In Italy, the total energy consumption in agriculture and food sectors decreased between 2013 and 2014, passing from 16.79 to 13.3 Mtep. Since energy consumption in food industry is nearly twice the one in agriculture (8.57 and 4.73 Mtep, respectively), it is very important to improve energy efficiency and use green technologies in all the phases of food processing and conservation. In Italy, a recent law (Legislative Decree 102, 04/07/2014) has made energy-use diagnosis compulsory for all industrial concerns, particularly for those showing high consumption levels. In the case of food industry buildings, energy is mainly used for indoor microclimate control, which is needed to ensure workers' wellbeing and the most favourable conditions for food processing and conservation. To this end, it is important to have tools and methods allowing for easy, rapid and precise energy performance assessment of agri-food buildings. The accuracy of the results obtainable from the currently available computational models depends on the grade of detail and information used in constructional and geometric modelling. Moreover, this phase is probably the most critical and time-consuming in the energy diagnosis. In this context, fine surveying and advanced 3D geometric modelling procedures can facilitate building modelling and allow technicians and professionals in the agri-food sector to use highly efficient and accurate energy analysis and evaluation models. This paper proposes a dedicated model for energy performance assessment in agri-food buildings. It also shows that by using advanced surveying techniques, such as a terrestrial laser scanner and an infrared camera, it is possible to create a three-dimensional parametric model, while, thanks to the heat flow meter measurement method, it is also possible to obtain a thermophysical model. This model allows assessing the energy performance of agri-food buildings in order to improve the indoor microclimate control and the conditions of food processing and conservation. [ABSTRACT FROM AUTHOR]

This paper contributes to the climate policy discussion by focusing on the challenges and opportunities of reaching net zero emissions by 2050 in Italy. To support Italian energy planning, we developed energy roadmaps towards national climate neutrality, consistent with the Paris Agreement objectives and the IPCC goal of limiting the increase in global surface temperature to 1.5 °C. Starting from the Italian framework, these scenarios identify the correlations among the main pillars for the change of the energy paradigm towards net emissions by 2050. The energy scenarios were developed using TIMES-RSE, a partial equilibrium and technology-rich optimization model of the entire Italian energy system. Subsequently, an in-depth analysis was developed with the sMTISIM, a long-term simulator of power system and electricity markets. The results show that, to achieve climate neutrality by 2050, the Italian energy system will have to experience profound transformations on multiple and strongly related dimensions. A predominantly renewable-based energy mix (at least 80–90% by 2050) is essential to decarbonize most of the final energy consumption. However, the strong increase of non-programmable renewable sources requires particular attention to new flexibility resources needed for the power system, such as Power-to-X. The green fuels produced from renewables via Power-to-X will be a vital energy source for those sectors where electrification faces technical and economic barriers. The paper's findings also confirm that the European "energy efficiency first" principle represents the very first step on the road to climate neutrality. [ABSTRACT FROM AUTHOR]

• Data about DHW in residential buildings were collected by survey in Southern Italy. • Contextual and personal factors influencing DHW usage were considered. • Descriptive statistics were performed to characterize DHW by climatic zone. • Inferential statistics were conducted to discover DHW usage patterns. • Four clusters of dwellings were identified considering DHW daily usage hours. In European efficient buildings, the share of energy use for DHW is a significant percentage of the heat requirement. The evaluation of DHW energy demand and consumption patterns has been neglected in the past and studies are located in Northern countries. This paper presents a survey conducted in Southern Italy. Descriptive statistics were performed to characterize DHW production by climatic zone. Inferential statistics were conducted to discover significant contextual and personal variables and identify usage groups. The most used energy source was biomass (49.3%), followed by methane gas (37.7%). Fireplaces were installed in the coldest zone, in detached houses, more in small municipalities (36%), and low-income families (32%). Solar systems were in 8% of dwellings having income higher than 28000€. Four clusters of dwellings were identified considering the daily usage hours. The eldest and less numerous households fell into the cluster with the lowest usage (3.5 h). Households with a percentage <25% of unemployed components had more probability to belong to clusters with more DHW usages. The paper contributes to fill the investigation in the Mediterranean area and provides a systematic approach to expand the limited knowledge about the influencing factors on the DHW production and usage. [ABSTRACT FROM AUTHOR]

Public acceptability appears an essential condition for the success of low-carbon transition policies. In this paper, we investigate the role of self-interest on citizens' preferences for the distribution of costs and environmental benefits of energy efficiency policies. Using a discrete choice experiment on nationally representative household samples of Sweden, Italy, and the United Kingdom, we first investigate preferences for national burden-sharing rules and for the distribution of environmental benefits accruing primarily in rural and/or urban areas. We examine the role of self-interest and self-serving bias in a correlational manner by looking at the effects of income and location of residency on preferences for these policy attributes. Moreover, we investigate the effect of self-serving bias on preferences for burden-sharing rules in a causal manner by experimentally priming randomly assigned groups of participants to feel either rich or poor. Our results suggest that the accountability rule is the most popular and the equal-amount rule the least popular burden-sharing rule. Further, policies with environmental benefits accruing primarily in rural areas are least preferred. We find some evidence for self-interest, especially through our correlational approach. Finally, across country samples, our results reveal heterogeneity in preferences for policy attributes and in the prevalence of self-interest. [ABSTRACT FROM AUTHOR]

• An integrated energy-economic analysis of Net ZEB office buildings was proposed. • A thorough discussion on the energy balance was provided for Italian climate zones. • Energy grid integrations, self-consumption, storage and losses were analyzed. • The cost assessment of office buildings was performed and compared to state-of-art. • The energy-economic benefit of a new Net ZEB office in Italy was demonstrated. Recently, the built environment has become one of the leading sectors in the challenge of decarbonization and energy consumption reduction. Because of the specific use and the complexity of the typological, architectural, and technical characteristics, non-residential buildings represent a challenge to overcome the nearly Zero Energy Building standard and to achieve the objective of Zero or Net Zero Energy Buildings. It is desirable that the energy produced in situ from renewable sources totally covers the energy demand (ZEB); alternatively, the amount of energy self-produced and dispatched into the grid must be greater than (or equal to) the energy withdrawn from the grid (Net ZEB). At the same time, it is necessary not to neglect the economic aspects. The aim of this work is to propose an integrated energy-economic analysis to demonstrate the actual feasibility of new Net ZEB offices in different Italian climate zones. Thus, the energy analysis of a reference building, based on consolidated and cost-effective envelope and HVAC systems, has been carried out through dynamic simulations. The photovoltaic field located on the roof provides the energy needed for lighting, appliances, and HVAC. The obtained results are the energy demand and the energy production from renewable sources for the case study in each Italian climate zone. Moreover, the paper discusses the complexity of the annual energy balance, considering contributions such as grid integrations, self-consumption, energy stored and losses. Finally, the cost assessment of the proposed building has been carried out and compared to the state-of-art, pointing out the economic feasibility of the Net ZEB. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dynamic evaluation of economic and energy benefits due to thermostatic valve installation. • Dynamic evaluation of economic and energy benefits due to heat metering installation. • The adoption of both thermostatic valves and heat metering least to a payback period lower than 2 years. • Analysis carried out considering several shapes of typical building. The aim of this paper is to propose a novel approach in order to accurately calculate the energy and economic savings due to the use of heat metering and thermostatic valves in residential buildings. The paper aims at proving that the present simplified approaches used in European Legislation may lead to significantly underestimate the profitability of this technology. The study is developed for four different typologies of buildings located in the city of Naples (South of Italy), including their geometrical and thermophysical properties. The buildings are first modelled in Google Sketchup and subsequently linked to the TRNSYS environment, which also includes a detailed model of the piping systems. The models allow one to evaluate, for every period of the year, energy demand, energy supplied by radiators, heat gains, transmission, etc. The developed models are used to calculate energy demands for three scenarios for each type of building: centralized heating systems not equipped with heat metering; thermostatic valves without heat metering; heat metering and thermostatic valves. The possible savings related to thermostatic valves and heat metering are estimated using the developed model. The results are compared with the ones provided by the Italian Standards. Results show that the thermostatic valves adoption leads to a significant reduction, up to 50%, of the thermal energy demand of the residential buildings and that all the proposed systems exhibit a remarkable economic profitability, with a payback period lower than 1.7 years. [ABSTRACT FROM AUTHOR]

The last ten years have witnessed an increase in publications focusing on bioeconomy as a proposal to confront the global challenges of climate change, depletion of non-renewable resources and ecosystem degradation. This paper investigates the scientific literature on issues related agricultural bioeconomy by applying a bibliometric network analysis. Bibliometric analysis is applied to the publications of the Scopus database during the period 2010–2020 in order to provide an overview of the main aspects that characterize agricultural bioeconomy. The results showed that out of a total of 1100 scientific papers, only 2.45% were published in 2010, while the corresponding share in 2020 was 20.81%. In the five years of 2016–2020, cumulatively, 70.63% of the publications were made, showing the dynamic evolution of bioeconomy. In addition, out of 85 countries in total, Germany and Italy are the two countries with most publications, while the fragmentation of research is evident with the creation of two main nodes, the European and the American. Moreover, keyword analysis showed that biomass and sustainability are two main recurring concepts, confirming that, currently, bioeconomy operates at three different levels: energy demand, land demand, and governance. It is apparent that to boost the development of agricultural bioeconomy, the following aspects should be assessed: the effective use of resources, an understanding of the key drivers of agricultural bioeconomy, and a clear perception of their associations. There is still no consensus as to which are the key factors that will accelerate its sustainable development. Our pursuit is to use the tools of bibliometric analysis to reach more critical conclusions regarding the agricultural bioeconomy, rather than approach it in a static way. [ABSTRACT FROM AUTHOR]

LCA (Life Cycle Assessment) is nowadays a commonly implemented approach for evaluating resource consumptions and for benchmarking purposes. It suffers some limitations, mainly related to its assumptions on linear resource -consumption behaviour as well as on the non-context specific data. On the other hand, it is an extremely powerful tool for decision-making support in the sustainability assessment of manufacturing processes, providing its well-structured approach and widely accepted procedure. Deepening the assessment capabilities of such a tool is thus an important opportunity. This paper is intended to build upon this concept by proposing an improved approach consisting in supplying in-process information concerning energy consumption and other process state conditions through thermography. The case of an Italian industrial company producing HDPE (High Density Polyethylene) nets for agriculture is taken as test bed case to show pros and cons of this idea. Actually, this approach resulted into a better assessment of the sustainability profile of the whole production process in terms of energy consumptions and environmental impacts. This in turn became an updated management tool for real-time decision making closer to the real conditions. [ABSTRACT FROM AUTHOR]

Improving energy efficiency in public buildings is one of the main challenges for a sustainable requalification of energy issues and a consequent reduction of greenhouse gas (GHG) emissions. This paper aims to provide preliminary information about economic costs and energy consumption reductions (benefits) of some considered interventions in existing public buildings. Methods include an analysis of some feasible interventions in four selected public buildings. Energy efficiency improvements have been assessed for each feasible intervention. The difference of the building global energy performance index (EPgl) has been assessed before and after each intervention. Economic costs of each intervention have been estimated by averaging the amount demanded by different companies for the same intervention. Results obtained show economic costs and the EPgl percentage improvement for each intervention, highlighting and allowing for the comparison of energy consumption reduction and relative economic costs. The research results come from data gathered from four public buildings, and as such they could not be used to generically identify cost-beneficial energy efficiency interventions for every context or building type. However, the data reveals useful cost based considerations for selecting energy efficiency interventions in other public buildings. [ABSTRACT FROM AUTHOR]

• Ground-source multiple chillers for space cooling in the tertiary sectors are investigated. • Hourly-based simulations of simple and hybrid configurations are performed. • A 7% increase in Energy Efficiency Ratio was achieved with the hybrid configuration. • An optimum value in the Energy Efficiency Ratio is achieved by varying the borehole depth. • A distance among probes greater than 10 m allows for efficient plant operation for several years. Air conditioning accounts for a large share of energy usage in residential and tertiary sectors. Renewable energy technologies offer promising solutions to reduce the environmental impacts of meeting buildings' energy loads. The possibility of using the soil as a thermal reservoir for heating and cooling systems has gained growing attention in the last decade due to its high potential for energy saving. In this paper, the benefits achievable using ground source chillers for air conditioning in an office building located in Southern Italy are discussed. A multiple chillers system coupled with a borehole heat exchanger is investigated and compared to conventional air-cooled and water-cooled systems. The analysis relies on detailed modeling of the main plant components and exploits a novel approach to calculating the thermal resistance of the borehole. Results show that the ground coupled multiple chillers system achieves a 6.516 average energy efficiency ratio, which is 53.2% higher than the reference air-cooled system and 6.5% higher than the conventional water-cooled system. In addition, a hybrid scheme that integrates the borehole heat exchanger with a cooling tower achieves a 19.5% reduction in make-up water consumption. A sensitivity analysis demonstrates that increasing the borehole depth could lead to a significant variation in the system performance, with different trends for simple and hybrid configurations. The proposed study puts forth a reference for the design and operation of this technology for covering the space-cooling demand of buildings in Mediterranean climates. [ABSTRACT FROM AUTHOR]

[Display omitted] • A research topic relatively new but with an increase interest in the last five years. • The largest scientific contribution from China, Australia and Italy. • The main journals in the field Building and Environment and Energy and Buildings. • Three main direction of research: thermal energy performance of buildings, ecological benefits and reducing the urban heat. • The main limitation of using green walls is the high cost of installing and maintenance. The continuous state of development of the human society imply a big effort and demand to generate and use more and more energy to power our lifestyle. The impact of human activity has negative effects on the environment and thus solutions to maintain or increase our development rate but in the same time to decrease the pressure on the environment must be developed. In this context, the purpose of this paper is to investigate if the use of green walls systems can be a solution to decrease the energy demands in buildings. The investigation include a bibliometric literature research, a scientometric analysis and an in-depth discussion. The data used for the research were obtained by interrogating the ISI Web of Science and Scopus databases, were selected using the guidelines of the PRISMA method and processed with the help of VOSviewer and Bibliometrix software. The research results indicate an increase interest in this topic in the last five years and that the use of vegetation in the constructed grey areas can bring a lot of benefits especially from environmental point of view. Green walls can be a solution to decrease the temperature on the wall surface in hot summer days and to prevent heat loses in the winter time, and thus have beneficial effects on the amount of energy required to maintain a proper interior temperature. The main limitation of using green walls is given by higher costs of installing and maintain the vegetation on walls, thus, finding new more economical, systems of green walls must be developed in the future. Considering all of this it can be state that green wall systems have the potential to become good solutions not just to improve the energy efficiency of buildings but also to create more sustainable urban areas. [ABSTRACT FROM AUTHOR]

In early 2011, Assimpredil ANCE (Association of construction firms and related industries in the provinces of Milan, Lodi, Monza and Brianza), together with the Muicipality of Milan, the Milano Chamber of Architects, IN/ARCH Lombardia and FederlegnoArredo, organized a competition to form a directory for high-performance, low-cost housing buildings proposals. Aim of the competition was to promote architectural quality, research and innovation in the housing sector by offering practical examples of high-performance, low-cost housing designs that fulfill the specific requirements. Participants were invited to submit designs on two themes: a 12 floors tower building and a 5 floors horizontal building, both intended with a GFA of about 5,000 sqm. The proposal were asked to deal with: • Prefabricated and/or traditional construction system with high performance standards. • Attention to the building's life cycle and its operating and management costs from the perspective of environmental sensitivity. • Control and containment of costs and construction times with the contractor guaranteeing completion. • Optimal usability and design flexibility. • Optimization of energy efficiency and acoustic performance, low CO2 emissions, minimization of indoor and outdoor pollution. • Milanese architectural identity given a contemporary sensibility. • Aggregability and flexibility of the apartments' building solutions. • Use of innovative components. After the selection made by the technical jury, 125 projects were admitted to the directory. A book has been published containing all projects told through images, technical drawings and a dashboard that summarizes, for each project, the technical performance and the assessment made by the qualitative jury. Editing the book, we had the opportunity to analyse in detail all projects, their structural characteristics, their performance and their architectural features. This paper aims to relate the results of this analysis, reporting, through a series of comparative studies, the state of the art of the Italian residential construction sector, its strengths and its weaknesses, the typological design strategies put in place and the available technologies. [ABSTRACT FROM AUTHOR]