Search

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]

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]

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]

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]

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 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]

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]

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]

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]

• 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]

[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]

• 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]

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]

• 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 recent years, Italy has seen a rapid growth in the PV (photovoltaic) sector, following the introduction of the FIT (feed in tariff) scheme known as Conto Energia. In July 2013 the Italian government definitively cut FITs, leaving only tax benefits and a revised net metering scheme (known as “Scambio sul Posto”) for new PV installations. In this scenario, the design of a new PV plant ensuring savings on electricity bills is strongly related to household electricity consumption patterns. This paper presents a high-resolution model of domestic electricity use. The model is based on Fuzzy Logic Inference System. Using as inputs patterns of active occupancy and typical domestic habits, the fuzzy model give as output the likelihood to start each appliance within the next minute. The model has been validated with electricity demand data recorded over the period of one year within 12 dwellings in the central east coast of Italy. The tool has been used to evaluate the self consumption percentage to correctly size a residential photovoltaic plant in a case study. A cost benefits analysis is presented to show the effectiveness of PV-generation in the new Italian scenario. [ABSTRACT FROM AUTHOR]

The aim of Sustainable Development Goal 7 is to ensure access to affordable, reliable, sustainable and modern energy for all. Increased energy efficiency is particularly important in the construction industry because urban agglomerations currently consume up to 80% of global energy, 40% of which is attributable to buildings. In countries like Italy however, where historical buildings constitute a significant part of the building patrimony, improving energy efficiency is not always straightforward as interventions must take into account the historical materials used as well as the context of the construction. Therefore, the aim of this research was to establish a methodology that would identify the most effective means of achieving energy efficiency taking into account the historical aspects of a building and its cultural context. The methodology proposed and described in this paper involves: preliminary analyses to identify the elements of value and the level of transformability of facades; the selection of different insulating materials; dynamic simulations of building behaviour; analyses of intervention costs in relation to each type of insulation and finally the preparation of a multi-criteria matrix to identify the most effective method of improving energy efficiency of a historical wall with differing degrees of transformability. Each insulating material was analysed in relation to heating and cooling requirements and material cost impact. The methodology was applied to a case study in the Province of L'Aquila, Italy. In the paper a multicriteria framework, for the improvements in the thermal efficiency of a building, it is presented. Specifically the attention is focused on heating requirements, cooling requirements and cost impact. The results indicate that, with respect to historical building, it is possible to adopt strategies finalyzed to improve the energy efficiency of these buidings, contributing in this way, also toward the SDG7. Specifically, the best performance for a wall with a high level of transformability can be obtained using calcium silicate, extruded polystyrene, kenaf and hemp, whilst, in the case of a wall with a low level of transformability, the best materials are calcium silicate, polyurethane and linen fiber. Finally, in the case in which external constraints prevent the application of a thick coat and internally there is limited space, the use of calcium silicate was found to be the best energy efficient measure. [ABSTRACT FROM AUTHOR]

The aim of this paper is to estimate the potential impacts of different COVID-19 scenarios on the Italian energy sector through 2030, with a specific focus on transport and industry. The analysis takes a multi-disciplinary approach to properly consider the complex interactions of sectors across Italy. This approach includes the assessment of economic conditions using macroeconomic and input-output models, modelling the evolution of the energy system using an energy and transport model, and forecasting the reaction of travel demand and modal choice using econometric models and expert interviews. Results show that the effect of COVID-19 pandemic may lead to mid-term effects on energy consumption. The medium scenario, which assumes a stop of the emergency by the end of 2021, shows that energy-related emissions remain 10% lower than the baseline in the industry sector and 6% lower in the transport sector by 2030, when compared with a pre-COVID trend. Policy recommendations to support a green recovery are discussed in light of the results. • Energy and emissions are compared for different COVID-19 scenarios in Italy by 2030. • The analysis is based on an integration of different models. • The scenarios consider different dates for the finish of the COVID-19 emergency. • The main drivers related to economic conditions and mobility demand are assessed. • Results highlight the contribution of the transport and industry sectors. [ABSTRACT FROM AUTHOR]

The EU27 countries exert significant influence on the global patterns of the CO 2 -Emissions-Water-Energy (CWE) nexus. However, whether the associated benefits are similar for all countries is unclear. In this paper, an EU27 multiregional input-output model, at a sector level to identify the inter-regional and -sectoral CWE flows, and clarify the regional, sectoral and worldwide patterns of EU27 CWE network is presented. The results revealed an environmental inequality across the EU27 and impacts on the rest of the world. The EU27 countries contributed 1.4 Gt less CO 2 emissions, 64.5 Gm3 less water utilisation and 49 EJ less energy consumption, compared to the rest of the world while generating the equivalent economic output in 2014. This has dramatic effects upon the global environment. Germany, France and Italy are the biggest beneficiaries in the CWE nexus in the EU27. It is recommended that the EU27 provide more technical support to upstream countries in the EU and elsewhere to strive to improve their resource utilisation efficiencies. • The critical Carbon-Water-Energy (CWE) flows across the EU27 are analysed. • The regional, sectoral and worldwide patterns of EU27 CWE network are clarified. • An environmental inequality across the EU27 and impacts on the rest of the world. • Germany, France and Italy are the biggest beneficiaries in the CWE network of EU27. [ABSTRACT FROM AUTHOR]

In the face of ever more ambitious global energy challenges, the European Union has set striving climate targets for 2030, planning to increase renewable energy penetration in the electricity generation as a key measure towards a clean energy transition. To respond to the challenge of keeping the increase in power sector costs, that inevitably arises when a profound reconfiguration of the electricity generation sector is expected, to the lowest possible, this paper aims to quantify the economic burden associated with the reduction of direct CO 2 emissions through a comparative assessment of various alternatives proposed for 2030 ranked in terms of their cost-effectiveness. A sensitivity analysis is also applied to the main economic and energy parameters that make up CO 2 mitigation costs to include those uncertainties that characterise future projections. The impact of electricity generation shares on CO 2 mitigation costs is assessed thus providing a basis for the definition of alternative configurations for the Italian electricity sector capable to achieve the desired environmental performance with a limited economic impact. Finally, results reveal that those scenarios based largely on natural gas and solar source are characterized by high mitigation costs, while energy efficiency is essential for a virtuous and clean electricity sector along with the use of all available sources in appropriate shares, both renewable and non-renewable, to pursue the highest environmental objectives in a cost-effective manner. Although related to the Italian case, the methodology provided in this study can be applied to any other electricity sector to ultimately evaluate the economic burden arising from possible different configurations. • Comparative analysis of scenarios for decarbonising electricity supply in Italy. • European Union Commission and National Energy Strategy projections are reviewed. • Costwise, coal phase-out is not as beneficial as other proposed configurations. • Energy efficiency is key to low-cost and highly beneficial environmental objectives. • High mitigation costs occur with large gas consumption and solar generating capacity. [ABSTRACT FROM AUTHOR]

• Electricity and electrification is a viable solution for the energy transition. • Electricity triangle assures a consistent framework for the energy transition. • Multifaceted benefits: energetic, environmental and socio-economic. • Conceptualization of a set of metrics for impact assessment. • A real case study (Italy) considering its evolution up to 2050. Greenhouse gases along with pollution generated by the present energy paradigm widely based on fossil fuels are providing large impacts in terms of climate change and the health of human and biological systems at large. A shift in the energy paradigm, from fossil fuels to renewable energy, is urgently needed for nature and society. This is what we refer to as the energy transition. An old commodity – electricity – can play a new key role in the energy transition. That can happen through what we call the electricity triangle involving electricity generation from Renewable Energy Sources, exploitation of electricity as the main energy vector, and electrification of the final energy uses in all sectors. The possible deployment of the electricity triangle must be carefully assessed in all its possible implications, from technological, economic, societal and environmental perspectives. In this paper, we conceptualize the electricity triangle as a viable approach to the energy transition, and we propose a set of holistic metrics to assess its possible impacts. We apply the electricity triangle framework to the case of Italy based on sectorial studies on RES generation and electrification in building, industry and transport sectors. Our results indicate that Italy in 2050 has the potential to achieve 85.6% penetration of RES in its electricity supply, while 41%, 53% and 42% of the energy consumptions in transport, residential, and industry sectors will be electrified. Ultimately, this would lead to a 68% reduction in CO 2 emissions compared to current levels. [ABSTRACT FROM AUTHOR]

• Heat accounting is an essential tool for increasing energy efficiency of buildings. • Indirect accounting systems are widely used in existing buildings generally showing not high accuracy. • A new hybrid method has been developed aimed at improving accuracy of heat accounting. • The hybrid method has been experimented at INRIM, the Italian metrology institute. • The hybrid method always shows higher accuracy in respect to the indirect one. Nowadays, two different heat accounting methods are available: the direct method, based on heat meters, and the indirect one, based on heat cost allocators. Unfortunately, in existing buildings, due to the plant configuration, heat meters are often technically unfeasible or not cost efficient, whereas heat cost allocators can be easily installed in almost all conditions. At the same time, the indirect method relies on a high number of interconnected devices with installation and operative conditions often variable within the same building and influencing the on-field metrological performances. In this paper, the authors propose a novel "hybrid" method for accurate heat accounting combining the advantages of indirect method with the higher accuracy typical of direct methods. The proposed method has been experimented at INRIM, the primary metrology institute in Italy, assessing the on-field performance in a virtual eight-apartments building. The experimental results show that the proposed method always presents improved accuracy. [ABSTRACT FROM AUTHOR]

The aim of this paper is to provide an overview about the distribution of the environmental impacts arising from different domestic functions (i.e. storing and preparing food, washing dishes, watching television, reading, personal cleaning, washing, drying and ironing clothes, home cleaning, heating, cooling, lighting and mobility) typically performed within a common family home. The method has general validity but for reasons related to the availability of data in the literature it has been applied by way of example only in three EU countries: Italy, Germany and France. The study was performed by using Life Cycle Assessment (LCA) in accordance with international standard ISO 14067 for determining the carbon footprint of different alternative domestic components, mainly appliances, for each function, by exclusively exploiting data from scientific literature. The functional unit is defined comprising all most common referred domestic activities of a family of three members within a house of 100 m2. The study identified an optimal configuration and a worse one of the domestic components in terms of carbon footprint, showing how a wise choice of these can greatly affect the overall impact by reducing it compared to the worst by more than 22% in Italy, 45% in Germany and 56% in France. The average impacts between the optimal and the worst configurations of Germany are higher than Italy (+27%) and France (+44%). Considering the impacts among the domestic functions in the average configuration, mobility was the most impactful in all the three countries (35–48%), followed by heating (17–26%), personal cleaning (10–13%) and washing dishes (8–13%), while cooling is consistent only in Italy (13%), against 5% in Germany and 2% in France. The study also allowed to identify some generic criteria for defining the optimal configuration: the increasing in energy efficiency, the choice of the least impacting energy source depending on the geographical location, ensuring water savings and the early replacement of older domestic components. Finally, by comparing some common measures for improving the domestic sustainability, these criteria proved to be more effective than solar systems and improved electricity mix. The provided outcomes may be used by manufacturers for improving their product in a more sustainable way as well as by legislator and end user, respectively for boosting and choosing the greener domestic components. Image 1 • LCA for estimating domestic environmental impacts based on scientific literature. • Application to three EU countries: Italy, Germany and France. • Assessing Carbon Footprint of different alternative domestic components for each domestic function. • Determining the optimal and the worst configuration of domestic components to minimize the impacts. • Comparing possible improvements for minimizing carbon footprint. [ABSTRACT FROM AUTHOR]

• A fruitful economic agreement between a mining industry and food production company. • The mine geological setting creates favorable condition for underground warehouses. • The dolomitic rock mass thermal behavior is described by a Finite Element Model. • The model is based on direct thermal conductivity measurements and monitoring data. • Compared to a surface deposit, the savings of specific energy consumption is 22% Underground food storage represents an interesting solution to the increasing demand for new food storage space, combining this demand with sustainable land exploitation. It also reduces the energy demand for food conservation, therefore limiting storage costs and greenhouse gas emissions. Moreover, atmospheric conditions can be easily controlled in underground warehouses, ensuring optimal long-term maintenance of the stored food. This paper presents a case study located in the Western Dolomites (Val Di Non, Trento, Italy), where mining activity is followed by the creation of storage space not only for food, but also for groundwater and a data hosting center. After the extraction of the dolomitic rock used in construction, underground excavated spaces are converted into warehouses, whose storage capability is improved once the inner surfaces have been protected by a gas-proof mineral hydraulic lime material, developed for this purpose. The thermal behavior of the rock mass over the first few years is analyzed by means of a Finite Element Model and compared with on-site monitoring data. Laboratory measurements of the thermal properties of the dolomite rock and the temperature data registered in the field permitted the development of a preliminary numerical model, in order to describe the heat exchange between the cavern and the rock mass and supply data to support future developments. Finally, the specific energetic consumption is compared with the one required by an aboveground deposit. [ABSTRACT FROM AUTHOR]

• The current and projected Italian electricity demand and supply is described. • Advantages and disadvantages of a possible reintroduction of nuclear are shown. • Waste management and public opinion resulted the main criticalities. • Major efforts need to be put in the waste management policy. • Communication to public on nuclear energy risk and potentiality should be pursued. Nuclear energy was adopted in Italy in the past to deal with the insufficient fossil fuels on the national territory. After a public vote subsequent to the Chernobyl accident, Italy abandoned the use of nuclear energy and nowadays adopts a mix of fossil fuels and renewable energy sources for electricity production. However, the urging environmental pollution and climate change issues are forcing Italy to realize a so-called "energy transition" towards a more sustainable energy production and consumption system. In this framework, following the examples of other countries, it could be re-evaluated the adoption of nuclear to reduce the consumption of fossil fuels. In the present paper, it is presented an overview of the nuclear energy history in Italy and the current and projected electricity demand and supply. Then, with reference to the Italian framework and policies, the main advantages and disadvantages of a hypothetical reintroduction of nuclear energy are presented. The analysis shows that the adoption of nuclear energy would bring several advantages in terms of lower emissions, higher security of supply and enabling of possible other technologies; the main disadvantages are related to the opposing public opinion and the nuclear waste management. [ABSTRACT FROM AUTHOR]

• A set of indexes to measure energy efficiency achieved in local areas is proposed. • The distance of each observation from efficient/ideal threshold is calculated. • Pilot testing was performed on 20 Regions of Italy. • A support to policy makers in financial resource programming is offered. The basic idea of this paper is that an efficient energy planning requires a deepened awareness of the state of place. By considering the complexity of this issue - that involves both production, consumption, impacts on the environment and policy aspects - a multidimensional analysis should be implemented. The aim of the study is to propose an innovative approach for achieving increased efficiency energy by reducing the existent differential among the local areas. The approach consists of two main steps: i) the building of LEEI (Local Energy efficiency Index) and further four sub-indexes - designed by using a Principal Component Analysis - for assessing the level of local efficiency; ii) the measurement of the distance between the score achieved in the ranking by each observation and a threshold calculated as best compromise situation - realized by using a redrafted Sen Index. This methodology has been tested on a sample of 20 Italian provinces. The findings allow to provide information to policy makers concerning the overall energy efficiency of an area through a vertical comparison among the observation; while the four sub-indexes offer specific indication about the multidimensionality of the analysed phenomenon. This final step helps to offer punctual information for a future allocation to the regions, for a financial resource programming on the bases of the real weakness. [ABSTRACT FROM AUTHOR]

The paper studies the relationship between energy saving behaviour, monetary drivers and non-monetary motivations in Italy, in a period, the end of the 1990s, when the energy industry was not yet liberalized, there were no energy saving incentive schemes, and the environmental sensitivity and information were lower. We consider as dependent variable the frequency with which individuals switch the light off when leaving a room; as monetary drivers, income and perceived energy costs; while non-monetary motives in our model are measured by proxies of pro-environmental attitudes, environmental information, social pressure, and pro-social behaviours. The analysis is based on probit and logit models estimated on a sample from the Multipurpose Household Survey dataset, conducted by the Italian Statistical Office. We find that individuals who were less concerned about environmental issues were also more attentive in energy saving behaviour, suggesting, together with results about income and perceived energy costs, that monetary motivations were primary in driving this energy saving behaviour. Such findings are robust to the inclusion of variables accounting for pro-social behaviours. Altruism by individuals who claim to be more concerned about broad environmental externalities may have adversely affected their propensity to optimize energy consumption. • We study the link among energy saving, monetary drivers and non-monetary motivations in Italy. • In the end of the 1990s, the energy industry was not yet liberalized and environmental sensitivity was lower. • We use probit and logit models and a representative sample from the Multipurpose Household Survey (ISTAT). • We find that monetary motivations were primary in driving energy saving behaviour. [ABSTRACT FROM AUTHOR]