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Industrial Kitchens are very energy-intensive businesses, consuming between five and seven times more energy per square meter than other commercial spaces like office spaces and retail stores. Still, very little research has been carried out on improving the energy efficiency of this industry. This paper presents the FIKElectricity dataset, a collection of electricity data from three Portuguese restaurant kitchens during their daily operation. The duration of the datasets spans three to four weeks in each industrial kitchen and comprises aggregated and individual appliance consumption, collected at 1 Hz and 1 5 Hz, respectively. The public release of FIKElectricity is expected to draw more attention from the research community to this overlooked industrial sector. The data collection and post-processing methods are thoroughly described in this paper, as well as the dataset organization. Examples showing the dataset's quality and instructions for its reuse are also provided. [ABSTRACT FROM AUTHOR]

The adoption of smart grids is becoming a common reality worldwide. This new reality is starting to impact energy customers as they face a dynamic grid in which they can actively participate. However, if energy customers are not prepared to participate actively, they can have their energy costs increased. This paper provides a review of acceptance models and customer surveys around the world made to assess the customers' perception and willingness to participate in smart grids. Contributing to this assessment, this paper presents a survey undertaken in Portugal. The survey results demonstrate a willingness, from the customer's end, to actively participate in smart grid initiatives. It was found that 92.9% of participants are willing to plan their energy usage to face hourly energy prices and that 95.0% of participants are willing to accept an external control of at least one appliance, enabling direct load control demand response programs. Also, the results identified two cognitive tendencies, negativity bias, and loss aversion, which can impact how customers participate in smart grids. These cognitive tendencies and the literature acceptance models demonstrate the importance of conducting social science studies targeting smart grids to fully achieve the efficient participation of end customers. [ABSTRACT FROM AUTHOR]

The world is facing many challenges to keep up with growing energy demand and greenhouse gas and pollutant emissions. A possible solution is to integrate renewable energy sources (RESs) into residences and create energy management systems (EMSs) that reduce consumption and relieve the main grid in critical hours. This paper is focused on analyzing different EMSs using solar photovoltaic (PV) modules and three energy storage systems (ESSs) to increase savings without affecting the user's needs, with thirty-three power consumption profiles and three energy tariffs over a 25-year investment to compare which solution presents the best economic result in each of the 297 analyzed scenarios. The results show that the higher the overall daily consumption values, the greater the profits for all EMSs. The lowest demand profiles lead to the best self-consumption and self-sufficiency results. PV-only systems with a tri-hourly tariff have the best overall results. In the case of battery operation, each case should be carefully analyzed in order to choose the correct technologies and tariff. The results also allowed us to verify that even though having more PV modules generates more energy, it can make a project less economically desirable. [ABSTRACT FROM AUTHOR]

Custom-built solutions for ageing, urban regeneration, energy efficiency, thermal performance, and well-being are contemporary challenges that have prompted considerable research over the past decades. In the construction field, subjects such as energy efficiency and thermal performance are often addressed within the scope of mandatory regulations, the suitability of construction solutions and the incorporation of technical equipment. Considering four residential structures for older adults under construction in Portugal, this paper aims to highlight the importance of a comprehensive approach to these issues, including architectural quality as the main target. In pursuit of this, a cohesive set of intervention principles guided the analysis: the adaptive reuse of raw materials; taking advantage of the site's conditions; vegetation (type and location); construction options and durability; solar exposure and shading; the pedagogy of building use; and the comfort and thermal perception. Several reflections emerge from the analysis: good architectural design must consider dynamic models incorporating each context and the site's conditions; the culture of use and maintenance and the notion of "adaptive comfort" are primary factors to enhance thermal performance and energy efficiency; and each building is a unique result of a complex negotiation process. Bridging research through practice, and multidisciplinary scientific integration enable engagement with reality and raise awareness of the constraints and challenges to innovation in LTC design. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising commodity, a renewable secondary energy source, and feedstock alike, to meet greenhouse gas emissions targets and promote economic decarbonization. A common goal pursued by many countries, the hydrogen economy receives a blending of public and private capital. After European Green Deal, state members created national policies focused on green hydrogen. This paper presents a study of energy transition considering green hydrogen production to identify Portugal's current state and prospects. The analysis uses energy generation data, hydrogen production aspects, CO 2 emissions indicators and based costs. A comprehensive simulation estimates the total production of green hydrogen related to the ratio of renewable generation in two different scenarios. Then a comparison between EGP goals and Portugal's transport and energy generation prospects is made. Portugal has an essential renewable energy matrix that supports green hydrogen production and allows for meeting European green hydrogen 2030–2050 goals. Results suggest that promoting the conversion of buses and trucks into H 2 -based fuel is better for CO 2 reduction. On the other hand, given energy security, thermoelectric plants fueled by H 2 are the best option. The aggressive scenario implies at least 5% more costs than the moderate scenario, considering economic aspects. [ABSTRACT FROM AUTHOR]

Improving the efficiency of energy use is of utmost importance in the context of climate change. Indeed, greater efficiency in the end-use of energy will make a significant contribution to lowering primary energy consumption and reducing CO2 and other greenhouse gas emissions. This paper presents an approach that enables a compact liquefied natural gas station to operate without being connected to the public electric grid. It is achieved by using the Boil-off gas generated by the vehicle supply process and feeding it to a generator which, together with a photovoltaic (PV) system, can produce electrical energy. Results from a year of trial operations at the station in Escariz, Portugal, demonstrate that it is possible to recover an average of 8.66 kg of Boil-off gas daily while generating a 345% excess of electrical energy when combined with the PV system, enabling the station to be self-sustainable in terms of electricity. Based on the experimental data and calculation methodology, the project was able to earn an estimated monthly revenue of €176.27 throughout the study period while also preventing the emission of 8549 kg of CO2 equivalent from natural gas combustion in vehicles. [ABSTRACT FROM AUTHOR]

Simple energy surveys and audits were performed in 60 processing industries of meat, dairy, horticultural and bread and pastry products, located in the North, Center, and Alentejo regions of Portugal. The number of refrigeration chambers, building infrastructure, and energy consumptions of the equipment used in the manufacturing processes were evaluated. The energy consumption of different manufacturing processes of regional food products were compared. The study aims to present several measures and best practices for the improvement of energy efficiency of the food sector. The implementation of simple and very cost‐effective transversal electricity savings measures such as awareness and/or training of operators, proper maintenance, and monitoring tasks, can benefit this sector. The tailored energy efficiency measures by sector are discussed. These energy efficient practice measures can offer savings at several levels, increasing productivity and competitiveness and improving the environmental impact, and thus the global sustainability of the Portuguese food sector. Practical applications: The adoption of efficiency measures by SMEs provides them the necessary instruments to become more competitive and dynamic in the market, due to the reduction of the energy costs. This condition allows funds to be redirected to areas such as logistics, ensuring an expansion to international markets. This paper presents several measures of energy efficiency, many of which require small investments. The objective of this study is to provide a reference guide, with the purpose of qualifying SMEs for the adoption of strategies to increase their competitiveness, productivity, and efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the temporal dependence in energy prices and demand using daily data of Portugal and Spain over the period 2007–2017. The methodology used is based on a stochastic Hidden Markov Model and the results indicate first that all significant relationships between energy prices and demands were found to be positive; second, spot prices are only time dependent on future prices and spot energy, while future energy is solely time dependent on spot energy behavior; third, future prices are not only autocorrelated but also time-dependent with spot energy and future energy demands level; and finally, spot energy is autocorrelated and time-dependent with future prices and future energy. Policy implications of the results obtained are presented at the end of the article. [ABSTRACT FROM AUTHOR]

Among all the activities in a society, construction has a key role in environmental, social, and economic pillars. Construction is also responsible for a considerable amount of waste production, energy consumption, pollutant gas emissions, and consumption of nonrenewable natural resources. Regarding energy consumption, a high demand for building operational energy has been observed in the last decades due to the more demanding requirements of the users with a continuous search for better thermal comfort in their homes, namely in developed countries. In Portugal, for instance, more than 20% of the electricity consumed is related to residential buildings, which is based on CO2 emissions and other pollutants that negatively affect the environment. Much of this consumed energy is a result of the HVAC systems installed inside buildings to provide users with thermal comfort. One exciting opportunity to mitigate buildings' operational energy consumption while contributing to thermal user comfort is the use of passive solutions. Even though several passive options are available and constantly under research, their use is still considered limited. This paper overviews and highlights the potential of energy-efficiency passive strategies, namely for Mediterranean-climate countries, where passive solar technologies can be set as a viable solution, as this climate is mainly known for its solar availability (solar hours and solar irradiance). A comprehensive overview of innovative and traditional housing passive solutions currently available is presented and discusses the main advantages, disadvantages, and concerns contributing to the optimal use of climatic conditions and natural resources in those regions. [ABSTRACT FROM AUTHOR]

This paper uncover a new perception of the dynamic interconnection between CO2 emission and economic growth, renewable energy use, trade openness, and technological innovation in the Portuguese economy utilizing innovative Morlet wavelet analysis. The research applied continuous wavelet transform, wavelet correlation, the multiple and partial wavelet coherence, and frequency domain causality analyses are applied on variables of investigation using dataset between 1980 and 2019. The result of these analyses disclosed that the interconnection among the indicators progresses over time and frequency. The present analysis finds notable wavelet coherence and significant lead and lag interconnections in the frequency domain, while conflicting relationships among the variables are found in the time domain. The wavelet analysis according to economic viewpoint affirms that renewable energy consumption helps to curb CO2 while trade openness, technological innovation, and economic growth contribute to CO2. The outcomes also proposed that renewable energy consumption decreases CO2 in medium and long run in Portugal. Therefore, policymakers in Portugal should stimulate investment in renewable energy sources, establish restrictive laws, and enhance energy innovation. [ABSTRACT FROM AUTHOR]

Climate change mitigation, the economy's decarbonisation, and energy poverty reduction are major challenges globally and for the European Union. However, competing agendas might create trade-off situations that hinder the achievement of these goals. Energy efficiency promotion in the residential sector, through the replacement of space heating and cooling equipment, can be an important solution to simultaneously contribute to reducing energy poverty and carbon emissions whilst improving households' comfort and wellbeing. This paper analyses the regional impact of replacing space heating and cooling equipment on energy poverty levels in the population using the Energy Poverty Vulnerability Index. Moreover, the impact on carbon emissions is also investigated. Results show that increasing equipment efficiency to regulation levels is only effective in reducing winter energy poverty, with a decrease in municipal vulnerability levels of about 18 per cent. Implementing a "deep change" in the heating and cooling equipment stock is significantly effective for reducing winter and summer energy poverty, respectively, 47.8 per cent and 26.3 per cent in average municipal levels, while significantly decreasing potential carbon dioxide emissions by 3554 kilotons. This transformation should be coupled with the improvement of buildings' energy performance and presents various significant challenges regarding financial investment and social justice that should be addressed by authorities at different scales. This study demonstrates the relevance of exploring the impact of space heating and cooling equipment replacement measures on energy poverty, efficiency and carbon emissions at the regional level while providing a replicable method for investigating this subject and producing valuable insights into other geographical contexts. [ABSTRACT FROM AUTHOR]

The main purpose of this research study is to explore higher education students' environmental knowledge, attitudes and behavior. To achieve this goal, a questionnaire was conducted among the students of a public higher education institution (HEI) in Portugal. Our findings result from 371 valid responses and allow us to conclude that most students have significant environmental knowledge, have environmentally friendly attitudes and are environmentally responsible in the areas of use of paper, recycling and energy consumption. Results also indicate that most students are aware of the importance of protecting the environment and consider themselves well informed about environmental issues. Students' main information sources of environmental information are television, social networks and the HEI they attend. We conclude that more attention should be given to HEIs, due to their significant potential to educate and train future decision makers in a society, to enhance a more protective approach to the environment. [ABSTRACT FROM AUTHOR]

This paper presents and discusses the application of a novel energy balance scheme for assessing energy efficiency in wastewater systems. The energy balance is demonstrated with a Portuguese real-life case study, using mathematical modelling to estimate the different energy components and to compute two energy efficiency indices. The total inflow intrinsic energy can represent a significant amount (>95%) of the total energy used in systems mainly composed of gravity sewers. The total input energy is significantly (four-times) higher in the wet season than in the dry season, mostly due to undue inflows (e.g., direct rainfall and infiltration). The potential for energy recovery strongly depends on the available head and flow rate at the delivery point, being 0.01 kWh/m3 in the current case, with a project payback period of 4 years. The energy balance components and the respective energy efficiency indices strongly depend on the considered reference elevation. Thus, a unique regional reference elevation is recommended in the calculations. [ABSTRACT FROM AUTHOR]

This paper seeks to identify promising sites and technologies, in Portugal, for co-located wave energy conversion and offshore aquaculture, whilst providing benchmark implementation references and guidelines to researchers. Accordingly, two case study sites are considered for deployment of five wave energy devices and up to six aquaculture species. A thorough analysis in terms of power ratios, efficiency, redundancy, species viability, device survivability and costs is performed, seeking to find viable co-located solutions. It is found that the Wave Dragon device yields the most promising energy demand coverage and energy output (5 226 to 6 817 MWh/year). Nevertheless, it may require rescaling towards optimal operation, while the OCECO 4 excels in terms of capacity factor (0.24–0.29) and default adaptation to the deployment sites. The WaveRoller® has the lowest single-unit cost (125 €/MWh) but requires up to nine units to cover all the energy demand targets. Larger wave farms are required for the BBDB and AquaBuOY, albeit with potentially greater economies of scale and single-unit redundancy. These sites also enable cultivation of most of the considered species, even under ideal conditions. Lastly, it is recommended that the devices enter survivability mode at a significant wave height threshold of 5.5 m. • Co-located potential of wave energy harvesting and offshore aquaculture in Portugal. • 5 WECs co-located with 3 + 3 aquaculture species in two deployment sites. • Estimation of energy/power ratios, efficiency, redundancy and species viability. • Wave Dragon stands-out on energy coverage, WaveRoller® on costs and OCECO on capacity factor. • 6/6 and 4/6 viable species for Figueira da Foz (2 ideal) and Sines (3 ideal) sites. [ABSTRACT FROM AUTHOR]

Renewable energies can benefit the water sector, reducing the cost and the environmental impact of water production. This paper presents a technical and economic assessment of a photovoltaic generation project to supply energy to a grid-connected seawater reverse osmosis (SWRO) desalination plant and of an associated battery energy storage system (BESS) using lithium-ion batteries. It examines the case study of the SWRO desalination plant on Porto Santo Island (Madeira, Portugal). The assessment is supplemented by a sensitivity analysis of several variables. The findings indicate that photovoltaic generation in desalination plants results in a lower levelized cost of energy (LCoE) and reduces the consumption of fossil fuel energy from the electrical grid. This can lead to lower desalinated water costs and greenhouse gas emissions. A feasible rated power range was identified for the photovoltaic plant in this case study, taking the internal rate of return, net present value, payback and LCoE into consideration. The results also point to a higher LCoE when a lithium-ion BESS is used. [ABSTRACT FROM AUTHOR]

The benefits of energy efficiency are recognized in multiple socio-economic spheres. Still, the quantitative impact on macroeconomic performance is not fully understood, as modeling tools are not thermodynamically consistent—failing to explicitly include the useful stage of energy flows and/or thermodynamic efficiencies in primary–final–useful energy transformations. Misspecification in the link between energy use and the economy underplays the role of energy use and efficiency in economic growth. In this work, we develop and implement the Macroeconometric Resource Consumption model for Portugal (MARCO-PT), 1960–2014. Based on the post-Keynesian framework developed for the United Kingdom (MARCO-UK), our model explicitly includes thermodynamic energy efficiency, extending the analysis to the useful stage of energy flows. The model's stochastic equations are econometrically estimated. The historical influence of key variables—namely thermodynamic energy efficiency—on economic output is assessed through counterfactual simulations and computation of year-by-year output elasticities. The MARCO-PT model adequately describes the historical behavior of endogenous variables. Although its influence has decreased over time, thermodynamic efficiency has consistently been the major contributor to economic growth between 1960–2014, with an average output elasticity of 0.46. Total useful exergy is also a major contributing factor, with an average output elasticity of 0.29. Both have a higher influence than capital, labor, or other energy variables (final energy, prices). An adequate integration of thermodynamic efficiency is thus crucial for macroeconomic models. [ABSTRACT FROM AUTHOR]

This study provides an in-depth assessment of the environmental performance of five public schools in the transition towards a low-carbon economy and a more sustainable model of society. Life cycle assessment (LCA) methodology is used to conduct the study. The school system includes several activities and processes clustered in three subsystems: management of the school building, training and learning activities (T&L) and mobility and transport (M&T). A detailed primary data inventory of energy and resources consumption was collected in five schools located in Spain and Portugal. Findings on climate change (CC), water depletion (WD), particular matter (PM), acidification (Ac), and human health (HH), as well as associated external cost (EC), are reported per student in one school year as reference unit, allowing the schools' individual performance comparison and identify the potential improvements. Considering the sample of schools, findings reveal that peculiarities of the schools, such as location, specialization, and level of education, are crucial for the environmental performance. Buildings are a relevant contributor to CC as well as heating and electricity needs, although their relevance is dependent on multiple factors. The M&T subsystem also has relevant weight on the metrics evaluated. Educational activities have a lower impact in absolute terms but, in some schools, it becomes the main contributor to HH due to paper and electricity consumption and manufacturing of equipment. External costs results are in the range of 11 to 38 EUR/student·year mainly caused by heating, electricity and wastes from the building subsystem, and the M&T subsystem. [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]

Addressing Europe's decarbonisation challenge involves widespread deployment of nearly zero-energy buildings, deep energy renovations and renewable energy integration in the building sector. Enhancing energy efficiency in public buildings necessitates tailored solutions and strategic planning involving Local Public Administration. This work focuses on advancing insights into the application of the PrioritEE Decision Support Tool in Portuguese public buildings, highlighting the energy and financial savings and carbon dioxide emission reduction potential. Using detailed building characterisation data from energy performance certificates, we applied the tool across 22 public buildings of diverse typologies in three distinct regions of Portugal, representing various public entities. Results demonstrate the tool's adaptability, enabling a comprehensive assessment of energy performance and facilitating the exploration of customised energy efficiency and renewable energy solutions. The research emphasises the critical role of user-friendly tools in aiding policymakers and local administration technicians in meeting national renovation targets and contributing to the broader energy transition objectives. [ABSTRACT FROM AUTHOR]

The most recent sustainability policies of each region of the world conjointly define that economic activities shall follow the principles of natural resource use minimisation, as well as eco-efficiency and circular economy promotion, in addition to the specific objectives defined in each policy. Most recently, a group of researchers has proposed innovative conceptual systems designated Water and Energy Integration Systems (WEIS) for issues related to water and energy use (two prominent categories of natural resources). These are based on engineering projects encompassing a multitude of processes and technologies. In this work, an assessment based on the determination of several sustainability and strategic-aims-related indicators is performed for two WEIS case studies set in the Portuguese process industry (in this case, a ceramic plant). Such an assessment serves as an expansion of previously performed studies on the economic and environmental viability associated with the installation of this type of system with the ultimate goal of proving the effective compliance of water- and energy-use-reduction-related results with sustainability and strategic aims (namely, the ones associated with the most recent policies and aspects associated with the social, economic, and environmental pillars of sustainability). The results for the overall assessment proved that the conceptualised WEIS are robust in terms of eco-efficiency, circular economy potential, and strategic objective achievement potential (with a 6.46% and 4.00% improvement for the aggregated eco-efficiency indicator having been obtained for, respectively, case studies 1 and 2, a null water discharge for both case studies, and a level of 8.58% and 6.69% of recirculated heat over total energy consumption, respectively). The obtained results prove the sustainability promotion effectiveness of the WEIS as conceptual systems. The overall set of indicators defined in this work are part of a methodology that may be used and adapted for further studies considering the innovative WEIS approach, with the specific results obtained in this work presented with the aim of their being used for comparison. [ABSTRACT FROM AUTHOR]

Rural farms constitute a vital component of a country's agricultural landscape, traditionally reliant on energy installations known for their reliability yet notorious for their energy-intensive and inefficient characteristics. While the smart farm concept, integrating renewable energy sources and resource management technologies, has seen widespread adoption in domestic and industrial sectors, rural farms have been slower to embrace these innovations. This study presents a groundbreaking solution, deployed on a rural farm in Portugal, resulting in an impressive 83.24% reduction in energy consumption sourced from the grid. Notably, this achievement translates to a substantial reduction in CO2 emissions, aligning with the growing need for environmentally sustainable farming practices. The technical intricacies of this pioneering solution are comprehensively described and juxtaposed with other scientific case studies, offering valuable insights for replication. This initiative represents a vital first step towards the integration or combination of conventional farming with photovoltaic energy production, exemplified by agrivoltaic systems. In conclusion, this research showcases the potential for rural farms to significantly enhance energy efficiency and financial viability, thereby contributing to a more sustainable and cost-effective agricultural sector. These findings serve as a model for similar endeavors, paving the way for a greener and more economically viable future for rural farming practices. [ABSTRACT FROM AUTHOR]

Current buildings are responsible for the highest energy consumption, exceeding polluting sectors such as industry and transports. In Portugal, a large part of the building stock was built in the 1970s and 1980s, but buildings dated from the 1960s and 1970s are the ones with the most anomalies and worst quality of construction and, therefore, worst energy performance. The renovation of those buildings can represent an excellent opportunity to correct and improve their energy deficiency and, with that, to promote a more sustainable building stock. The ETICS system is the most used for the renovation of buildings in Portugal due to its lower cost, quick application and thermal efficiency, but it doesn't solve other problems that may exist, such as structural safety and interior organization of the existing building. The application of prefabricated systems in the envelope has proved to be successful in improving energy efficiency, allowing new volumes and extra areas while contributing to the structural resilience of existing buildings. This paper aims to describe the current situation of the buildings renovation in Portugal and to discuss the potential of innovative envelope retrofitting solutions, using natural materials like timber, and is more concerned with the problems of existing buildings and the need for comfort and space for the occupants. [ABSTRACT FROM AUTHOR]

The need for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in internal combustion engines has raised the opportunity for the use of renewable energy sources. For the progressive replacement of fossil fuels like diesel, those derived from the sustainable management of forest resources may be a good option. In Portugal, pine trees (pinus pinaster) are among the most widely cultivated tree species. Turpentine can be extracted from their sap without harming the tree. Turpentine is known to be a good fuel with a lower viscosity than regular diesel but with a comparable caloric value, boiling point and ignition characteristics, although it is not widely used as a compression ignition fuel. Moreover, recent research has highlighted the possibility of substantially increasing the turpentine yield through biotechnology, bringing it closer to economic viability. The present study investigates the performance, pollutant emissions and fuel consumption of a 1.6 L four-cylinder direct-injection diesel engine operating with several blends of commercial diesel fuel and turpentine obtained from pine trees. The aim of this study was to assess whether it would be possible to maintain or even improve the performance, fuel consumption and GHG and pollutant emissions (HC, NOx, CO and PM) of the engine with the partial incorporation of this biofuel. Turpentine blends of up to 30% in substitution of regular diesel fuel were tested. The main novelties of the present work are related to (i) the careful testing of a still-insufficiently studied fuel that could gain economical attractiveness with the recent developments in yield improvement through biotechnology and (ii) the tests conducted under fixed engine load positions typical of road and highway conditions. The addition of this biofuel only slightly impacted the engine performance parameters. However, a slightly positive effect was observed in terms of torque, with an increase of up to 7.9% at low load for the 15T85D mixture and 6.8% at high load being observed. Power registered an increase of 9% for the 15T85D mixture at low speed and an increase of 5% for the 30T70D mixture at high speed when compared to the reference fuel (commercial diesel fuel). While the efficiency and fossil GHG emissions were improved with the incorporation of turpentine, it had a mixed effect on polluting emissions such as unburned hydrocarbons (HC) and smoke (PM) and a negative effect on nitrogen oxides (NOx). NOx emissions increased by 30% for high loads and 20% for low loads, mainly as an indirect effect of the improvement in the engine performance and not so much as a consequence of the marginally higher oxygen content of turpentine relative to commercial diesel fuel. [ABSTRACT FROM AUTHOR]

Despite Portugal's effort to reduce carbon emissions, the country still emits about 1.6% of the European Union's CO2 emissions. Meanwhile, limited empirical studies have been undertaken in the context of Portugal. As a result, this study examines the asymmetric and long-term impact of CO2 intensity of GDP, energy consumption, renewable energy and economic growth on CO2 emissions in Portugal from 1990 to 2019. The nonlinear autoregressive distributed lag (NARDL) is employed to uncover the asymmetric connection. The findings show that there is nonlinear cointegration among the variables. The long-run estimation reveals a positive change in energy consumption positively affects CO2 emissions, while a negative shock in energy consumption has a neutral effect on CO2 emissions. Furthermore, positive shocks of economic growth and CO2 intensity of GDP enhance environmental deterioration by increasing CO2 emissions. Meanwhile, the negative shock of these regressors positively impacts CO2 emissions. In addition, positive shocks in renewable energy enhance environmental quality, while negative shocks in renewable energy increase environmental deterioration in Portugal. Policymakers should focus on reducing per-unit energy usage and CO2 efficiency gains, which would necessitate a significant reduction in CO2 intensity and energy density of GDP. [ABSTRACT FROM AUTHOR]

This article presents causal recipes leading to high and low energy consumption efficiency performances using fuzzy set Qualitative Comparative Analysis (fsQCA). The study found that several causal conditions are sufficient for high energy efficiency performance, including several fiscal and financial incentive policies, a highly educated population, many completed dwellings, and low GDP. The study also found that high inequality in completed dwellings and completed reconstructions, coupled with a low GDP and a low number of policies, lead to high energy consumption efficiency performance. In addition, the analysis showed slight differences between the yearly consistencies, suggesting that time effects are not a concern. On the other hand, a low education level, Gini coefficient, few completed dwellings and reconstructions, coupled with a low number of fiscal and financial policies, are the causal conditions leading to low energy consumption efficiency performance. The study's results suggest that policymakers and stakeholders should consider a combination of several causal conditions when implementing energy efficiency policies. The study also highlights the need for policies focusing on education, fiscal and financial incentives, completed dwellings, and reconstructions to achieve high energy efficiency performance. [ABSTRACT FROM AUTHOR]

This article investigates the impact of fiscal and financial incentives for energy efficiency labels on eco-friendly houses (houses with high energy efficiency certificates, such as A+, A, B, and B−) in 18 municipalities in the Lisbon metropolitan region during the period 2014–2020. The empirical results indicate that the variables of fiscal incentive policies for energy efficiency labels, income per capita, credit agreements for the purchase or construction of a house, and the number of completed dwellings in new constructions for family housing encourage eco-friendly houses. In contrast, the variable number of completed reconstructions per 100 completed new constructions has a negative impact. Although this study is constrained by data limitations resulting from the short period under analysis and the moderate number of municipalities available, it advances the discussions around energy efficiency in residential properties in Portugal. Furthermore, it investigates the effectiveness of tax incentive policies for energy efficiency seals as an instrument for promoting ecological houses in the municipalities of the Lisbon metropolitan area. Thus, the need to study the Portuguese capital stands out as it is the most populous city in the country and concentrates a large part of the economic activity. [ABSTRACT FROM AUTHOR]

Building information modelling (BIM) is the first step towards implementing Building 4.0, where virtual reality and digital twins are key elements. The use of unmanned aircraft systems (UAS/drones) to capture data from buildings is nowadays a very popular method, so a methodology was developed to digitally integrate the photogrammetric surveys of a building into BIM, exclusively with the use of drones. Currently, buildings are responsible for 40% of energy consumption in Europe; therefore, the interconnection between BIM and building energy modelling (BEM) is essential to digitalize the construction sector, increasing competitiveness through cost reduction. In this context, the BlueWoodenHouse Project aims, among other activities, to characterize the solutions/systems of building materials and monitor the temperature, relative humidity and CO2, as well as energy consumption, of a single-family modular wooden house located in the north of Portugal, with 190 m2 and three users. Thus, the experimental monitoring results, of this case study, were used to validate the numerical model developed in the DesignBuilder simulator, which includes the building envelope's 3D geometrical data obtained by one of those aircraft, in order to demonstrate the usefulness of drones for the optimization of solutions, from the energy point of view. [ABSTRACT FROM AUTHOR]

• 11 EU countries registered a convergent pattern in per capita energy use in. • The convergence was persistent Ireland and Spain. • Divergent behaviour was observed in UK, Germany, Portugal and Italy. • The EU membership enhanced economic growth and the energy use. The European Green Deal initiatives refer to pollution reduction and management of climate changes. The aim of this paper is to analyze the stochastic convergence in per capita energy use in the EU-15 countries in the period 1970–2019. Besides the application of unit root tests with low power, this research proposes subsampling confidence intervals (asymmetrical and equal-tailed confidence intervals) to assess stochastic convergence. The approach based on confidence intervals provides additional information on the persistence of the energy use. 11 countries in the EU-15 registered a convergent pattern, while per capita energy use in Ireland and Spain was persistent. A divergent behaviour was observed in the case of the UK, Germany, Portugal and Italy. The three groups of countries were used in constructing an ANOVA/ linear Dependent Dirichlet Process (DDP) mixture model to show that economic growth is a significant cause for per capita energy use in countries with convergent behaviour. Moreover, EU membership enhances economic activity and also energy use. Specific policies are proposed for each group of countries to decline the per capita energy use. [ABSTRACT FROM AUTHOR]

The main objective of this research is to assess the impact of energy certificate ratings (EPCs) on the value per m2 of Portuguese housing sales. Data from 289 Portuguese municipalities between 2014 and 2019, analysed with a fixed effects panel and method of moments quantile regression, were used. EPCs with high energy efficiency ratings (e.g., A+, A, B, and B-) are used as a proxy for dwellings with "green" or "environmentally friendly" certificates. On the other hand, ratings with a low energy efficiency (e.g., C, D, E, and F) are used as a proxy for dwellings with "non-green" or "not environmentally friendly" certificates. The results support that EPCs associated with green housing increase the value per m2 of housing sales, and those associated with non-green housing decrease the sales value. It was also found that municipal GDP, tax/financial incentive policies for energy efficiency, and the number of completed dwellings in new constructions for family housing will increase sales value. On the other hand, credit agreements and completed reconstructions reduce sales value. Lastly, the results and outgrowths of this study will support the policymakers and governments in developing consistent policies and initiatives that promote the "green" or "eco-friendly" dwellings in Portugal or in similar economies. [ABSTRACT FROM AUTHOR]

Understanding how to address today's global challenges is critical to improving corporate performance in terms of economic and environmental sustainability. In wastewater treatment systems, such an approach implies integrating efficient treatment technologies with aspects of the circular economy. In this business field, energy costs represent a large share of operating costs. This work discusses technological and management aspects leading to greater energy savings in Portuguese wastewater treatment companies. A mixed methodology, involving qualitative and quantitative aspects, for collecting and analysing data from wastewater treatment plants was used. The qualitative aspects consisted of a narrative analysis of the information available on reports and websites for 11 wastewater management companies in Portugal (e.g., technologies, treated wastewater volumes and operating costs) followed by a review of several international studies. The quantitative approach involved calculating the specific energy consumption (kWh/m3), energy operating costs (EUR/m3) and energy operating costs per population equivalent (EUR/inhabitants) using data from the literature and from Portuguese companies collected from the SABI database. The results suggested that the most environmentally and economically sustainable solution is algae-based technology which might allow a reduction in energy operating costs between 0.05–0.41 EUR/m3 and 15.4–180.8 EUR/inhabitants compared to activated sludge and other conventional methods. This technology, in addition to being financially advantageous, provides the ability to eliminate the carbon footprint and the valorisation of algae biomass, suggesting that this biotechnology is starting to position itself as a mandatory future solution in the wastewater treatment sector. [ABSTRACT FROM AUTHOR]

Purpose: Common octopus is the fishing species with highest economic revenue in Portugal, and its consumption per capita is very high. The majority of catches come from the small-scale fleet with pots and traps. The aims were to assess main environmental impacts of common octopus' fishery with traps and pots in the Algarve region, where the most important fleet size and landings volume occurs, and to find if there are significant differences between both fishing gears. Methods: The assessment includes standard LCA impact categories, fishery-specific impact categories, and quantification of macroplastics and microplastics emitted to the environment. The functional unit selected was 1 kg of octopus and the study was a 'cradle to gate' system. The scope included fishing operations until the product is landed at the harbour. Primary data was obtained by face-to-face questionnaires from 22 vessels, with an average of 1005 pots and 1211 traps per vessel, and 372 pots and 234 traps lost annually to the environment. Plastic pots have a concrete block and traps are a metal framed covered by plastic netting. Each trap or pot is connected to the main line at regular intervals. Unlike traps, pots do not need bait. Results and discussion: Fuel contribution to global warming is very high and where the highest potential exists to lower down the carbon footprint. The fuel use intensity resulted in 0.9 L/kg of octopus. The bait used in traps is significant and raises further environmental costs related with fuel consumption. The use of traps represents more than two times the impacts found for pots in all the categories studied except ecotoxicity categories. Zinc use was the main contributor to ecotoxicity categories, but it has not been included in other fishery LCA studies. It was estimated that 12.2 g of plastics is lost to the environment per kg of octopus. The loss of macroplastics from fishing gears was the highest contributor. Conclusions: The carbon footprint obtained was 3.1 kg CO2 eq per kg of octopus, being lower compared to other seafood products, and less than half compared to octopus caught with trawling. Pots and traps are highly selective fishing gears, causing negligible disturbance to the seafloor. The stock is not assessed, but management measures exist and can be improved. A drawback exists related with gears lost to the environment. [ABSTRACT FROM AUTHOR]

Energy retrofitting is one of the critical elements in national energy efficiency action plans in Egypt and Portugal to achieve energy efficiency in the buildings' sector. Therefore, this study explores the techno-economic feasibility of proposed simple passive retrofitting solutions using nature-based and conventional thermal insulation materials to the existing dwellings in the traditional coastal settlements under the Mediterranean climate. Two case studies, one representing a typical coastal, traditional wooden house in the west center of Portugal and another, a conventional brick house in the Delta region in Egypt, were selected. Each case study house was simulated using energy performance assessment tools (Energy+) before and after retrofitting in both locations using similar insulation properties. The results showed that energy consumption decreased by (29% and 43%) for cooling and (23% and 45%) for heating under different circumstances. Furthermore, the shortest simple payback model was projected by 16 and 25 years, with profitability achieved in 17 and 27 years for a proposed retrofitting solution. Also, a new propinquity between Portuguese and Egyptian Architecture was brought out. [ABSTRACT FROM AUTHOR]

Energy return on investment (EROI) is a ratio of the energy obtained in relation to the energy used to extract/produce it. The EROI of fossil fuels is globally decreasing. What do the declining EROIs of energy sources imply for society as a whole? We answer this question by proposing a novel EROI measure that describes, through one parameter, the efficiency of a society in managing energy resources over time. Our comprehensive societal EROI measure was developed by (1) expanding the boundaries of the analysis up to the useful stage; (2) estimating the amount of energy embodied in the energy-converting capital; (3) considering non-conventional sources such as the muscle work of humans and draught animals; and (4) considering the influence of imported and exported energy. We computed the new EROI for Portugal as a case study. We find a considerably lower EROI value, at around 3, compared to those currently available, which is stable over a long-time range (1960–2014). This suggests an independence of EROI from economic growth. When estimated at the final stage, using conventional methods (i.e., without applying the four novelties here introduced), we find a declining societal EROI. Therefore, our results imply that the production of new and more efficient final-to-useful energy converting capital has historically kept societal EROI around a stable value by offsetting the effects of the changing returns of energy sources at the primary and final stages. This will be crucial in the successful transition to renewables. [ABSTRACT FROM AUTHOR]

The urban water sector significantly contributes to energy consumption and greenhouse gas (GHG) emissions. Detailed assessment of the wastewater system input provides opportunities for improving the water, energy, and emissions nexus. The inflow of water not requiring treatment into wastewater systems is acknowledged worldwide. These undue inflows can increase the footprint of these systems. Together with flooding and discharges, monitoring of undue inflows is not a common practice in water utilities. Three levels of analysis are proposed to assess the magnitude of the impact of undue inflows in the water–energy–greenhouse gas (W-E-G) emissions nexus: at a national level, calculation of performance indicators using yearly data; at the utility level, performance indicators calculations using yearly, monthly, and sub-daily data; at the subsystem level, calculations using mathematical modeling. Results show the implications of undue inflows on energy and GHG emissions, including the effect of flooding and discharges. The importance of undue inflows in the W-E-G nexus is sustained by the results of three case studies in Portugal. Each level of analysis is tailored to the information available, allowing a step-by-step understanding of the relationship between water, energy consumption, and emissions of the urban drainage inflows. [ABSTRACT FROM AUTHOR]

The effect of energy policies on the energy performance of residential properties/houses in nineteen Portuguese districts from 2014 to 2021 was investigated. A linear random-effects model regression was used as the method in this empirical investigation. The empirical results indicated that the income per capita has a negative effect on residential properties with high energy efficiency certificates (e.g., A+, A, and B) and a positive impact on residential properties with low energy efficiency certificates (e.g., C, D, E, and F); the codes and standards energy policies for energy efficiency have a positive effect on residential properties with high energy efficiency certificates (e.g., A, B, and B−) and residential properties with low energy efficiency certificates (e.g., C, D, E, and F); the fiscal and financial incentive policies for energy efficiency have a positive effect on residential properties with high energy efficiency certificates (e.g., A+, A, and B) and a negative effect on residential properties with B− energy certificate, and also a negative effect on residential properties with low energy efficiency certificates (e.g., C and D) and a positive effect on residential properties with an F energy certificate; the information and education policies of energy efficiency have a positive effect on residential properties with high energy efficiency certificates (e.g., A+, A, and B) and residential properties with low energy efficiency certificates (e.g., C, D, and E); and, finally, the consumer credit per capita has a positive effect on residential properties with high energy efficiency certificates (e.g., A+, A, and B) and a negative effect on residential properties with low energy efficiency certificates (e.g., C, D, and F), as well as a positive effect on residential properties with an F energy certificate. [ABSTRACT FROM AUTHOR]

Energy-poverty (EP) must be considered an energy-related issue since buildings are a central part of people's daily lives. Thus, it has an important role in energy-related policy implementation. Even though the European Union (EU) has endorsed general energy efficiency through the Energy Efficiency Directive and Energy Performance of Buildings Directive recast, it was the Clean Energy Package for all Europeans that clearly highlighted EP. The growing concerns with EP have also been emphasised in subsequent directives and initiatives. Despite some regulatory framework and the milder climate situation, the proportion of the population experiencing thermal discomfort in southern and eastern European countries, namely in the winter season, is relatively high, reflecting the poor thermal performance of building stock, low family incomes and high energy prices, among others. The current work analysed the EP evolution in Portugal in the EU context, and the Thermal Building Regulations and Energy Efficiency Policies developed, aiming to add insight into the effectiveness of those policies concerning EP mitigation in Portugal as an EU Member state. Moreover, a critical debate on the potential to lower the EP Portuguese situation was also an objective to pursue. It is plausible to admit that reducing EP by acting on residential building stock, namely through the increase of energy efficiency and comfort, plays a key role in improving the living conditions, namely of vulnerable households and deprived areas. This will also decrease energy consumption and dependence while further promoting a smarter, sustainable and inclusive society, contributing to economic growth. [ABSTRACT FROM AUTHOR]

Energy conservation is a popular topic in scientific research today, despite the specific effects of energy conservation awareness still being investigated. Significant research about this topic has been performed in different countries. However, the research conducted so far concerns methods of energy saving, a building's energy efficiency and new technologies; however, a significant part of society will live in technologically old buildings for a long time, which requires the involvement of consumers to save energy. To explain how energy-saving awareness plays a role in energy-saving behavior, this study will take city dwellers as a research facility and integrate relevant literature and disciplines, such as information and knowledge management, with the mechanistic study of how energy-saving awareness influences behavior that conserves energy and establishes a sensible behavior model. The survey was conducted in Poland, Portugal and Italy with over 18,000 people who declared that they are responsible for managing the household. In addition to the quantitative and qualitative research defining the percentage of behavior, the research group gave answers to the assessment of energy management, both assessing itself and the activities carried out in its own households on the Likert scale. The SERVPERF method was used for this. The results of the study clearly show that not only do economic factors affect energy saving, but also an informed society that cares about resource management. The research carried out presents the measures undertaken to save energy, and also identifies the level of knowledge and behavior that reflect pro-ecological trends and care for the sustainable development of the city, country and one's own household. [ABSTRACT FROM AUTHOR]

Balancing energy demand and supply will become an even greater challenge considering the ongoing transition from traditional fuel to electric vehicles (EV). The management of this task will heavily depend on the pace of the adoption of light-duty EVs. Electric vehicles have seen their market share increase worldwide; the same is happening in Portugal, partly because the government has kept incentives for consumers to purchase EVs, despite the COVID-19 pandemic. The consequent shift to EVs entails various challenges for the distribution network, including coping with the expected growing demand for power. This article addresses this concern by presenting a case study of an area comprising 20 municipalities in Northern Portugal, for which battery electric vehicles (BEV) sales and their impact on distribution networks are estimated within the 2030 horizon. The power required from the grid is estimated under three BEV sales growth deterministic scenarios based on a daily consumption rate resulting from the combination of long- and short-distance routes. A Monte Carlo computational simulation is run to account for uncertainty under severe EV sales growth. The analysis is carried out considering three popular BEV models in Portugal, namely the Nissan Leaf, Tesla Model 3, and Renault Zoe. Their impacts on the available power of the distribution network are calculated for peak and off-peak hours. The results suggest that the current power grid capacity will not cope with demand increases as early as 2026. The modeling approach could be replicated in other regions with adjusted parameters. [ABSTRACT FROM AUTHOR]