Search

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]

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]

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]

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]

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]

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]

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]

Transport is one of the sectors of the energy consumption where the presence of renewable energies is lower and its increase is hard to achieve especially in countries that import all the fuels that they consume. This paper addresses the progress that Portugal is making toward a more sustainable transport sector. A near- and medium- term scenario analysis is performed, based on the energy consumption in the past and on a detailed evaluation of the trends for renewable energy in the transport sector. The near-term scenarios aim at portraying the conditions that allow the country to fulfill the target of 10% renewable share in transportation established by the European Union. The medium-term scenarios highlight the implications, in terms of emission reduction and of energy independence, deriving from the use of electric vehicles and natural gas, synthetic and fossil, as alternatives to liquid fuels. The results show that electric vehicles would substantially reduce the total energy consumption and the greenhouse gas emissions, while the promotion of routes for synthetic natural gas would contribute to taking advantage of local resources. The paper also provides some insights about the design of future policies to build a more sustainable transport sector. [ABSTRACT FROM AUTHOR]

This paper describes recent work on the development of a wireless-based remote monitoring system for household energy consumption and generation in Madeira Island, Portugal. It contains three different main sections: (1) a monitoring system for consumed and produced energy of residencies equipped with photovoltaic (PV) systems, (2) developing a tool to predict the electricity production, (3) and proposing a solution to detect the PV system malfunctions. With the later tool, the user (owner) or the energy management system can monitor its own PV system and make an efficient schedule use of electricity at the consumption side. In addition, currently, the owners of PV systems are notified about a failure in the system only when they receive the bill, whereas using the proposed method conveniently would notify owners prior to bill issue. The artificial neural network was employed as a tool together with the hardware-based monitoring system which allows a daily analysis of the performance of the system. The comparison of the predicted value of the produced electricity with the actual production for each day shows the validity of the method. [ABSTRACT FROM AUTHOR]

• Effects of cold and hot ambient conditions on the same CPV/T are studied. • A multiphysics (thermal-fluid coupling) 3D FE model of CPV/T is developed. • Effects of fluid flow rate on CPV/T performance are described. • Different cross-section coolant fluid channels are studied. • Annual CPV/T performance for Lisbon (Portugal) and Gävle (Sweden) is a case study. In the presented paper, we developed a partnership with the Swedish company Solarus AB to study the performance of a CPV/T under very distinct climate zones: Sweden and Portugal. We focus on thermal effects and their influence on the CPV/T's energy efficiency. Therefore, we develop an electromagnetic-thermal finite element model (FEM) of the CPV/T in 2D and 3D, capable of computing the heat transfer occurring due to the flow of cooling fluid. Furthermore, we use the developed model to evaluate temperature conditions over the different layers of the photovoltaic panel and fluid temperature along the CPV/T. The evaluation shows that it is the CPV/T cooling structure that has a major influence on CPV/T's performance when it functions in climate zones with very different temperature scales along the year. The shape of cooling channels, for example, must continue to ensure a better heat transfer, leading thus to a more uniform distribution of the temperature along with the receiver. Also, fluid flow rates must be carefully selected to avoid solar cells reach their maximum operating temperatures (85 °C). [ABSTRACT FROM AUTHOR]

• New calculation of CSE criteria (Cyclist Specific Effort) and cycling ventilation rates. • New method for evaluating best cycling paths, with less pollutant's inhalation and less effort. • Cycling-User-friendly tool with distance, time, effort and pollutants inhalation, as input criteria. • Validation that exposure to pollutants is sensitive to environmental conditions and user characteristics. There is a growing effort on policies and projects to support a modal shift towards active transport modes, namely the bicycle. The selection of preferred routes, and consequently the implementation of cycle routes, are usually based on distance, time and safety, not on exposure to pollutants. This paper presents a methodology to compare alternative routes, considering not only journey distance and time but also cyclist effort and exposure to pollutants mainly from traffic emissions (that also relates to the cyclist effort). The main purpose of this work is to develop a simple tool that allows municipalities and end users to estimate the effort required and the exposure to pollutants on potential routes, therefore supporting planning and design of infrastructure. The concept of cyclist specific effort (CSE) is developed in this work. The cyclist's highest specific ventilation rates are estimated from a direct relationship with the CSE, based on the specific characteristics of the users and on a calibrated relationship in the lab. A case study is presented for the route that connects two campuses of the University of Coimbra, Portugal (≈5 km). Results show that some alternative routes, which are generally not considered due to the increment of distance and/or time, can significantly reduce exposure to pollutants while requiring the same or even less effort. A reduction of approximately one third in the inhalation of pollutants from traffic emissions (33.1%) is possible by choosing a slightly longer route (6%) and requires a similar total effort. [ABSTRACT FROM AUTHOR]

Indoor environmental quality (IEQ) and energy conservation in schools are complex challenges. A significant part of the energy demand in these buildings addresses ventilation and temperature indoors. When confronted with money/energy constraints, the tendency of school boards is to cut on IEQ requirements, compromising the comfort of the occupants or worse, their health. Besides local energy production, either electrical or heating, major focus on building management systems' (BMS) operation has been suggested, aiming at developing evidence-based energy conservation measures. Based on two field studies, a joint approach of energy and IEQ auditing was developed, establishing a state of the art of the current situation of the secondary schools in Portugal. The present study aims at enhancing energy efficiency in schools unveiling that it is possible to improve the HVAC systems' operation and optimize energy use and costs, while maintaining good environmental conditions. This paper also seeks to contribute to the implementation of energy efficiency plans (EEP) in school buildings, presenting a comprehensive methodological approach on energy consumption in this typology of buildings, centred on the fundamental role of BMS and their proper programming. The obtained results show that there is a considerable potential for reducing energy consumption and improving energy use—in one of the schools by simply adjusting the BMS operation schedule, a decrease between 20 and 36% of the useful thermal energy consumption is expected (14.1–24.7 kWh/m2); in other occasions, a significant IEQ improvement is expected due to longer HVAC running period. [ABSTRACT FROM AUTHOR]

Abstract Road freight transportation accounts for a significant share of the worldwide CO 2 -Emissions, indicating that respective operations are not sustainable. Regarding the forecasted increase in CO 2 -Emissions from this sector, undertaking responsibilities for its environmental impact are needed. Although technical and strategic solutions to reduce emissions have been introduced, or are in development, these rarely yield instant emission reduction potentials. A strategic approach to reducing them instantly, based on the given infrastructure and existing vehicle fleet, may be achieved through route optimization. Route optimization is a well-researched topic in the transportation domain. However, it is mainly used to reduce transportation times and expenses. Rising expectations towards sustainability by authorities and consumers led to an increased interest in route optimization in which environmental externalities, such as fuel consumption and CO 2 -Emissions are minimized. This paper introduces a Geographic Information System (GIS) based 3D-Routing-Model, which incorporates models to estimate vehicle fuel consumption while taking effects, such as road inclination and varying velocities into account. The proposed model utilizes a Digital Elevation Model (DEM) to enrich a road network with elevation data. The 3D-Routing-Model is applied in different distribution scenarios within the framework of an artificial company in the Lisbon Metropolitan Area, Portugal to evaluate the effects of road inclination on vehicles fuel consumption and its proportional CO 2 -Emissions. Results indicate that eco-friendly routes can yield significant fuel and emission saving potentials of up to 20% in the tested scenarios. However, eco-friendly routes are characterized by longer distances as well as operation times, which leads to increased expenses. The question remains if companies within the transportation sector are more interested in maximizing their profits, or investing in a sustainable future. [ABSTRACT FROM AUTHOR]

The meat product industries play a major role in many global economies. In several countries, it is the industry with a higher economic weight within the food industries. As refrigeration systems are indispensable within the production processes, it is important to improve the overall energy efficiency in order to reduce the electricity consumption in these industries. The electrical energy consumption of the Portuguese meat industries is evaluated in this paper. The field study shows that electrical energy accounts for 66.5 % of the overall energy consumption in slaughterhouses, 85 % in sausage houses and 92.5 % in ham industries. Relatively to the refrigeration systems of these industries, results show that the average compressor nominal power per unit of cold room volume is comprised between 0.072 and 0.043 kW/m. The average value of the specific electrical energy consumption for the slaughterhouses was 149 kWh/ton, 660 kWh/ton for sausage houses and 1208 kWh/ton for ham production industries. Finally, a potential reduction of the electricity consumption based on simple energy efficiency measures was estimated in 24 % for the slaughterhouses, 13 % for the sausage houses and 8 % for the ham industry. [ABSTRACT FROM AUTHOR]

Abstract: Portugal is a country with an energy system highly dependent on oil and gas imports. Imports of oil and gas accounted for 85% of the country’s requirements in 2005 and 86% in 2006. Meanwhile, the share of renewable energy sources (RES) in the total primary energy consumption was only 14% in 2006. When focusing only on electricity production, the situation is somewhat better. The share of RES in gross electricity production varies between 20% and 35% and is dependent on the hydropower production in wet and dry years. This paper presents, on a national scale, Portugal’s energy system planning and technical solutions for achieving 100% RES electricity production. Planning was based on hourly energy balance and use of H2RES software. The H2RES model provides the ability to integrate various types of storages into energy systems in order to increase penetration of the intermittent renewable energy sources or to achieve a 100% renewable island, region or country. The paper also represents a stepping-stone for studies offering wider possibilities in matching and satisfying electricity supply in Portugal with potential renewable energy sources. Special attention has been given to intermittent sources such as wind, solar and ocean waves that can be coupled to appropriate energy storage systems charged with surplus amounts of produced electricity. The storage systems also decrease installed power requirements for generating units. Consequently, these storages will assist in avoiding unnecessary rejection of renewable potential and reaching a sufficient security of energy supply. [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]

Fossil fuel dependency in Portugal is represented in around 76% of the total primary energy use, from which almost half is associated to the road transport sector. The reduction of imported fossil energy, pollutants and CO2 emissions is seen as a solution to a more sustainable energy system. This paper analyzes the market penetration of battery electric vehicles in the road transport sector as an alternative and more efficient technology, considering its maximum share in the transport sector in 2050. The main goal is to evaluate the energy consumption, air pollutants (including CO2 emissions), and the economic impacts of conventional and electric vehicles in Portugal. The environmental Kuznets effect in the studied factors is also evaluated. Life cycle methodology was applied to the "fuel" production and use stage, and to the materials of the vehicle. Although reducing energy consumption and emissions is essential, the relation of such impact within the region economy is also extremely important. Based on a Kuznets curve hypothesis, some of those impacts were possible to co-relate with the gross domestic product evolution in Portugal. The evolution of the energy source share, energy production efficiency, vehicle type share in the Portuguese light duty vehicle fleet, and technology efficiency, was also considered. Although the electrification of the road sector can potentially lower the fossil fuel importation, the electricity demand should increase. Nevertheless, it is estimated that around 43% of the energy consumption, 47% of CO2 emissions, and 17%-40% of air pollutants could be reduced with the expected electric vehicle evolution. [ABSTRACT FROM AUTHOR]

The consequences of climate change heavily influence the Mediterranean region. However, the Portuguese CO2 emission shows a decreasing tendency, the evolution of livestock and animal production have significantly increased its level in agriculture. The article investigates the role of the agricultural output and energy consumption in the environmental pollution in Portugal. It explores the short and long-run cointegration between carbon dioxide emissions and agricultural activities such as crop production, livestock production, and agricultural land use applying Autoregressive Distributed Lag (ARDL), Granger causality, Newey-West Standard Errors regression, as well as ARIMA model for the period of 1960-2015. The causality relation between CO2 emissions and agriculture is also analyzed. The Augmented Dickey-Fuller (ADF) unit root tests suggest that all variables are stationary. ARDL model demonstrates a long-run relationship between CO2 emissions, agriculture, and energy consumption. Results indicate that agricultural activities and energy use have a positive effect on environmental pollution; therefore, the Portuguese agriculture needs to achieve a higher level of sustainable development, with reducing the impact of animal husbandry and intensive crop production. [ABSTRACT FROM AUTHOR]

• A methodology for identifying cost-effective solutions for districts is presented. • The usefulness of the methodology is shown in a Case study located in Portugal. • All the analysed centralised approaches are cost-effective. • A carbon emissions neutral district can be achieved maintaining cost-effectiveness. Building renovation plays a key role in reducing greenhouse gas emissions and achieving the climate protection goals. The district scale approach is one of the most effective approaches to accelerate this process of reducing the energy consumption in the building sector as increasing its renovation rates. In this context, the Energy in Buildings and Communities Programme of the IEA, IEA-EBC started in 2017 the project "Annex 75: Cost-Effective Building renovation at District Level Combining Energy Efficiency and Renewables" aiming to explore optimal opportunities of district renovations from a cost-benefit perspective. IEA Annex 75 is a co-operative effort of participants from 13 different countries: Austria, Belgium, China, Czech Republic, Denmark, Germany, Italy, The Netherlands, Norway, Portugal, Spain, Sweden and Switzerland. In this paper, key elements of the methodology developed in Annex 75 project are presented. This methodology aims to facilitate the identification of optimal solutions in different European countries, enabling to explore similarities and differences amongst them, with a particular focus on the balance between energy efficiency measures and renewable energy measures. After a detailed description of the developed methodology, it is also applied to a case study located in Portugal and results obtained are analysed in detail. The paper demonstrates the usefulness of the methodology for evaluating and identifying optimal solutions in renovations at district scale, as well as for successfully addressing the research questions investigated by the Annex 75 project. They also provide some insights regarding the specific case study, showing that, although district systems are not usual in the current Portuguese context, these centralised solutions in renovations at district level are cost-effective interventions that can lead to significant reductions of greenhouse gas emissions and non-renewable primary energy use. [ABSTRACT FROM AUTHOR]

Abstract: The growing concerns about climate change and security of supply opened way to a significant investment in the exploitation of RES (renewable energy sources) for electricity generation. The possibility of achieving 100% RES systems is being debated but concerns about costs, storage and backup capacity still prevail. This paper addresses the topic of renewable energy scenarios for the electricity sector, analyzing different possible future strategies for the Portuguese system. Each one of these strategies is characterized according to the expected electricity consumption and renewable share, with the final aim of analyzing a possible 100% RES scenario. The energy system analysis tool EnergyPLAN was used for simulating each scenario for a one year period. The 100% RES scenario is found to be theoretically possible but a significant increase on the total capacity of the system would be necessary to ensure no shortfall during the summer season. The outcome would be the existence of critical excess electricity production during the winter and also a significant increase of the total cost of the system. The importance of the interconnection as stabilization measure along with the inclusion of storage systems is discussed for a system highly dependent on renewable energy sources. [Copyright &y& Elsevier]

Reducing demand by increasing end-use energy efficiency on the demand side of energy systems may also have advantages in reducing fossil dependency and greenhouse gas (GHG) emissions on the supply side. This paper addresses interactions between energy supply- and demand-side policies, by estimating the impact of measures addressing end-use energy efficiency and small-scale renewables uses in terms of (1) avoided large-scale electricity generation capacity, (2) final energy consumption, (3) share of renewables in final energy and (4) reduction of GHG emissions. The Portuguese energy system is used as a case study. The TIMES_PT bottom-up model was used to generate four scenarios covering the period up to 2020, corresponding to different levels of efficiency of equipment in buildings, transport and industry. In the current policy scenario, the deployment of end-use equipment follows the 2000-2005 trends and the National Energy Efficiency Action Plan targets. In the efficient scenarios, all types of equipment can be replaced by more efficient ones. Results show that aggressive demand-side options for the industry and buildings sector and the small-scale use of renewables can remove the need for the increase in large-scale renewable electricity capacity by 4.7 GW currently discussed by policy makers. Although these measures reduce total final energy by only 0-2 %, this represents reductions of 11-14 % in the commercial sector, with savings in total energy system costs of approximately 3,000 million euros-roughly equivalent to 2 % of the 2010 Portuguese GDP. The cost-effectiveness of policy measures should guide choices between supply shifts and demand reduction. Such balanced policy development can lead to substantial cost reductions in climate and energy policy. [ABSTRACT FROM AUTHOR]

The contents of this paper address the concept of net zero energy in industrial and commercial buildings, focusing on the definition which accounts for energy losses by converting each energy carrier used in the building to source energy. Therefore, this paper presents a sample of several source energy conversion factors commonly used in the United States, Canada and in most European countries. Energy efficiency in industrial and commercial buildings is discussed throughout the work, including a brief review of energy-efficiency measures which can be implemented in order to increase the efficiency and improve the performance of these energy-intensive buildings. Net metering is introduced due to its importance towards achieving net zero energy, along with its potential benefits and challenges, as well as a brief overview of policies currently being implemented around the world. In addition, various aspects regarding the classification of the weighting system and calculation of zero energy balance are also addressed. Finally, a case study is presented to evaluate whether five distinct enterprises located in Portugal can achieve annual net zero energy by deploying on-site renewable sources in the area available within their site boundary. This case study is based on a developed algorithm which allows the evaluation of these enterprises according to different symmetric and asymmetric weighting systems. The concepts of demand response and net metering are also briefly discussed and presented as a viable and cost-effective solution to aid any building achieving annual net zero energy. • Energy efficiency is mandatory to achieve net zero energy in industrial buildings. • Several process specific measures can be adopted in each industrial sector. • Source energy conversion factors are presented to assist the balance calculation. • The choice of weighting factors heavily influences the building energy balance. • Asymmetric weights favouring generation are suitable for net zero-energy buildings. [ABSTRACT FROM AUTHOR]

Abstract: In the last years Portugal has been at the forefront in the deployment of electricity from renewable energy sources (RES-E). The Portuguese national energy strategy 2020 (NES 2020) aims to reinforce Portugal’s leadership in sustainable energy and to attain the ambitious goals set in the government programme, namely consolidating the renewable energies cluster in Portugal, which will represent approximately by 2020 more than three times the 35,000 jobs estimated in 2010 and further developing the industrial cluster related with energy efficiency, creating 21,000 new jobs. The main purpose of this paper is to perform a prospective study and to discuss the various factors that influence the appraisal of sustainable systems integrating environmental, social and economic dimensions, mainly focusing on the RES-E jobs case by means of a multiobjective Input–Output model, based on current data availability. [Copyright &y& Elsevier]

Abstract: This work is a part of a wider study involving the economic and environmental implications of managing construction and demolition waste (CDW), focused on the operation of a large scale CDW recycling plant. This plant, to be operated in the Lisbon Metropolitan Area (including the Setúbal peninsula), is analysed for a 60year period, using primary energy consumption and CO2eq emission impact factors as environmental impact performance indicators. Simplified estimation methods are used to calculate industrial equipment incorporated, and the operation and transport related impacts. Material recycling – sorted materials sent to other industries, to act as input – is taken into account by discounting the impacts related to industrial processes no longer needed. This first part focuses on calculating the selected impact factors for a base case scenario (with a 350tonnes/h installed capacity), while a sensitivity analysis is provided in part two. Overall, a 60year global primary energy consumption of 71.4thousand toe (tonne of oil equivalent) and a total CO2eq emission of 135.4thousand tonnes are expected. Under this operating regime, around 563thousand toe and 1465thousand tonnes CO2eq could be prevented by replacing raw materials in several construction materials industries (e.g.: ferrous and non-ferrous metals, plastics, paper and cardboard). [Copyright &y& Elsevier]

Abstract: Due to the high energy consumption associated with the building sector, several legal documents with the aim of promoting energy efficiency have emerged in recent years, e.g. the Directive 2002/91/EC on the energy performance of buildings (EPBD) and its recast on 19 May 2010, Directive 2010/31/EU. The EPBD led many countries to adjust their own building energy-related regulations. The Portuguese thermal regulation for residential buildings, “Regulamento das Características do Comportamento Térmico de Edifícios (RCCTE)”, is a part of the transposition of the EPBD to Portuguese law. The main objective of this paper is to analyse the RCCTE in order to study the influence of some parameters considered important to the energy efficiency of buildings on energy performance and on the final energy certification rating. [Copyright &y& Elsevier]

Abstract: In Portugal, there is a critical need for architects to incorporate energy-conscious strategies on the process of refurbishment design. Passive design technology is still widely unknown or misused by Architects, to a large extent because information on these issues is scarce, mostly referring to foreign climatic and building contexts. There is also a great need for user-friendly tools, like the LT method, particularly for demonstrating and validating its use in the Portuguese context. This paper presents the LT-Portugal software, which is an energy design tool that can quickly assess the energy use (lighting, cooling, ventilation and heating) and thermal comfort implications of design options – both in existing projects and also to inform design decisions. Despite the complexity of the analysis, the LT method is easy to use and to apply to a range of situations. It is thus an ideal to assess refurbishment strategies, to which it has been applied before, and to make comparisons between various refurbishment options. [Copyright &y& Elsevier]

Abstract: The global financial crisis has brought severe impacts on the Portuguese economy. In this context, the Portuguese government has recently adopted harsh measures that will have deep impacts on peoples'' lives. This paper discusses the influence of these measures on economic growth, social well-being, energy consumption as well as its impacts on the environment using a multi-objective linear programming model based on input–output analysis. Uncertainty is captured taking into account different model coefficient settings by means of interval programming tools. [Copyright &y& Elsevier]

Abstract: In the early fall of 2010 a survey questionnaire was conducted to assess residential wood combustion (RWC) practices in the 18 districts of mainland Portugal. This paper describes and analyses the results from a bottom-up approach, based on this telephone survey, which enabled the characterisation of RWC practices in each district. Additionally, emission factors and source profiles obtained from different RWC tests, allowed the estimation of CO, CO2, PM2.5 and particulate organic compound emissions on a country-scale. The type and number of RWC appliances, each with their specific emissions factor and the amount and type of fuel used vary significantly on a district scale. The energy consumption in RWC appliances was estimated to be 35 342 TJ y−1. The estimated emissions of PM2.5 from RWC in Portugal (10.96 kt y−1) represent 30% of the estimate for different source activities reported in a recent inventory. The national emissions of OC and EC were estimated to be 5.32 and 0.53 kt y−1, respectively. It was also estimated that the total CO2 emissions from RWC in Portugal are 1.7 Mt y−1. The levoglucosan emissions contribute with between 7.8% and 16.1% of PM2.5 emissions from RWC. [Copyright &y& Elsevier]

Abstract: This paper analyses the energy consumption and CO2 emissions of biological hydrogen production from sugarcane and potato peels using life cycle assessment methodology for the Portuguese scenario. Potato peels are assumed to be produced locally from Portuguese potato cultivation. Sugarcane is assumed to be imported from Brazil and fermented in Portugal. The uncertainty is quantified by a Monte Carlo approach. Biohydrogen was compared with natural gas reforming, electrolysis and other energy resources such as diesel and electricity. Between bioH2 feedstocks, sugarcane stands out with the lowest values for energy consumption and CO2 emissions with 0.30–0.34 MJ of consumed energy and 24–31 g of CO2 emitted per 1 MJ of H2 produced. However these results do not have a major contribution to the Portuguese energy independency problem. On the other hand potato peels feedstocks are more attractive, presenting values of 0.49–0.61 MJ/MJH2 and 60-77 gCO2/MJH2. According to Portuguese production capabilities, it is estimated that biohydrogen will be able to supply 3100 vehicles of a typical Portuguese urban taxi fleet or up to 1.4 million passenger cars with a daily commuting distance of 30 km. [Copyright &y& Elsevier]

The European energy performance building regulations, Directive 2002/91/EC - Energy Performance of Buildings Directive (EPBD) of the European Parliament and Council, require that new buildings present minimum standards of energy efficiency. Accordingly the Portuguese regulations require that new buildings comply with minimum requirements on the energy performance and must have an energy performance certification through witch an energy efficiency label is attributed to the housing. It also require that existing buildings must have an efficiency energy label when submitted to a commercial transaction or to a deep rehabilitation. To achieve this goal the study of energy performance of existing buildings must be done. As many essentials elements to determine the U-factor and other thermal parameters are unknown, Portugal developed a simplified methodology to achieve the thermal performance of existing buildings. The aim of this paper is to present the study of the energy performance of a set of social dwellings that were constructed during the decade of 80, constructed before the former building thermal comfort specifications came into force. During the study the referred methodology was applied and conclusions of the energy efficiency label obtained were put out as the encountered difficulties. The study also compares the results obtained by the simplified methodology and by the detailed methodology that is required by Portuguese building thermal comfort specifications. [ABSTRACT FROM AUTHOR]

Abstract: In a scenario of large scale penetration of renewable production from wind and other intermittent resources, it is fundamental that the electric system has appropriate means to compensate the effects of the variability and randomness of the wind power availability. This concern was traditionally addressed by the promotion of wind resource studies and acting in the supply side of energy and using energy storage technologies. However, in electric system planning, other options deserve to be evaluated, namely the options related with the energy demand. The most severe problems due to the wind power intermittence happen during the peak load hours. Thus, instead of trying to replace the lost capacity due to the intermittence, other option is to act in the energy demand side, with the aim of reducing the consumption in such hours. The demand-side management technologies are an option that must be considered to reduce and manage the wind power intermittence. The present paper analyzes the possible impact of demand-side management and demand response, with the aim of enabling the integration of the growing intermittent resources in Portugal. [Copyright &y& Elsevier]

Abstract: This paper presents a general overview on the subject of sustainable building and urban design in Portugal – within the Southern-European context. It focuses on its evolution, the most striking aspects, present needs and future trends. Various case studies are presented, including the integration of renewable energy systems at urban and building scale. [Copyright &y& Elsevier]

In this paper a study on thermal refurbishment of old Portuguese elementary school buildings is presented. The type of school under analysis is the one adopted by a large construction campaign carried out from the 40's to the 60's of the twentieth century and, in a big part, still in use. This building stock has a very poor thermal performance and its refurbishment was evaluated starting with a case study of a school in the central region of Portugal, where some experimental measures were performed and a calculation method was applied for the heating energy consumption estimation. Then, different solutions for thermal refurbishment were tested and their technical and economical consequences were evaluated. Finally, the national impact of the thermal refurbishment of the whole building stock was characterised in terms of energy savings. [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]

[Display omitted] Several Southern European countries are paradoxical examples of high energy poverty, revealed by multiple indicators, despite their mild winter climates. Energy poverty may be quantified by using expenditure-based indicators that compare energy expenditure to net income, as a measure of how elastic is the net income to pay for energy. Because of the mild winter season and low efficient buildings, paying for space heating is not a top priority expense for most of the households. This cultural behavior exposes people to continuous cold conditions. This paper aims at a better understanding of the performance of energy poverty expenditure-based indicators in the Portuguese case-study, using national statistics raw data from 2015. The main conclusions of this study are twofold. First, a moderate heating cost is calculated by the difference between the median actual energy expenditure for households with a central heating system and those without any. Calculated equivalised values range from 116 (Lisbon region area) and 202€ (central region). The same order of magnitude is found for the difference between very low and very high incomes total energy expenses, which is 285€. Therefore, a reliable energy poverty indicator should rely on its capacity to evaluate net-income elasticity to pay for expected energy expenditure. From the evaluated indicators, the minimum income standard (MIS) is the more stable, identifying 27.8% households potential energy-poor. Still, this figure should be complemented with tracking MIS households where actual is significantly below expected energy expenditure (15.6%). Regarding energy policies the MIS energy-poor households should be the target to implement: (i) subsidised acquisition of heating equipment and (ii) subsidised energy during the winter season (mainly during cold spells). Further energy policies should mitigate the potential energy poverty of median-income households by boosting the refurbishment of the energy-inefficient buildings. Those households are particularly critical since they do not have sufficiently high incomes to fulfill the required house improvements, and, because of their low energy expenditure, payback returns are remarkably high. [ABSTRACT FROM AUTHOR]

The evaluation of the effects of local actions for climate change mitigation is essential for the assessment and design of effective policies, as well as for the adequate diffusion of good practices. However, existing methodologies based on the comparison of the total energy use and/or accountable greenhouse gas emissions of two different years do not lead to an isolated quantification of the effects of local policy actions. This happens because many causes of change in the local energy use and accountable emissions are not designed and/or controlled by the local authorities, namely economic dynamics, and national policies. This paper proposes a new model for disaggregating the total observed changes into a number of sources of change, thus enabling an estimated quantification of the effects originating from local policies alone. The applicability of the model is demonstrated by a concrete case study, the municipality of Porto in Portugal. • Proposed method quantifies the effect of local actions on climate change mitigation. • Local changes in GHG emissions are disaggregated into different contributing causes. • The methodology is based on a sequential decomposition analysis. • Advancement towards better evaluation of municipal or local policy actions. • Validation achieved by applying the method to the municipality of Porto (Portugal). [ABSTRACT FROM AUTHOR]

• Assessment of the thermal discomfort in Portuguese public schools in free-running conditions. • Reduced cost refurbishment of a prototype classroom in a Brandão school in Porto, Portugal. • Experimental characterization of the prototype before and after refurbishment, winter and mid-season analysis. • Quantification of energy consumption vs discomfort in winter for different intermittent heating strategies, after refurbishment. Public school buildings represent an important share of public buildings in Europe, some of them built several decades ago. In Portugal, there are about 5800 public schools, many of them in free-running conditions, with significant thermal discomfort and without any heating strategy due to economic restrictions. This work studies the Portuguese Brandão school model (from the '70 s), which comprises about 100 non-refurbished basic schools. This paper suggests the passive refurbishment of these public schools with some affordable interventions, regarding the climate features and the reduced capacity to support the operating costs. A prototype classroom was prepared in a Brandão school, in Porto. The in situ experimental campaign consisted of temperature, relative humidity, CO 2 concentration and energy consumption measurements. The prototype construction included the improvement of the envelope and of the technical systems. The main goals of this work are: (1) the comparison of the prototype in-service thermal performance in pre-existing conditions and the improvement after the refurbishment in free-running conditions or with some intermittent heating strategies; (2) the establishment of discomfort indexes for the assessment of the discomfort for Mediterranean temperate climate; (3) the quantification of the energy consumption vs discomfort regarding the passive refurbishment strategy and the intermittent heating strategies. When comparing the before and after refurbishment results, the mean daily discomfort indicator has decreased from 34.7 °C.hour to 25.2 °C.hour in free-running conditions and after the refurbishment has decreased from 25.2 °C.hour to 11.9 °C.hour for 3 heating hours strategy and to 2.5 °C.hour for 10 heating hours strategy. There was an expected increase of CO 2 inside the classroom for the corresponding months before and after refurbishment, although the mean CO 2 was below the required 1500 ppm. [ABSTRACT FROM AUTHOR]

Abstract: The main goal of this paper is to disclose, in a synthetic manner, some of the technological advances which occurred on the glass industry of Portugal, particularly in Marinha Grande known as the town of the glass, during the period 1864–1888. Relevant information concerned with the evolution verified on the construction and structure of glass pot furnaces, as well as with the refractories of silicoaluminous type based on clay (national and imported) needed to line up furnace walls and to build the glass pots is disclosed too. As regards to refractories production information is also provided relatively to the raw materials being used, its preparation, design and manufacture. Information about the education and skills acquired by the glassmakers is referred to. [Copyright &y& Elsevier]