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Designing self-sufficient renewable energy systems is becoming a key issue in the energy sector due to modern energy goals. Due to the variability of renewable energy sources, very often it is necessary to adopt hybrid configurations of renewable energy systems and advanced energy storage to achieve self-sufficiency. However, the adoption of complex and novel systems, including technologies as photovoltaic, wind turbines, biomass gasifiers, hydrogen energy storage, must to be founded on a comprehensive analysis of the system operation under different conditions and its energy and economic performance in the investigated case study. Therefore, the aim of the present paper is carry out a comprehensive feasibility analysis of a novel hybrid renewable energy system achieving a high self-sufficiency level. The system integrates a wind turbine and photovoltaic panels to match the energy load of a tourist resort in Agkistro, Greece. Energy exceeding the load is directed to the energy storage system based on the battery and hydrogen tank. As backup energy source, a wood gasifier is used. The investigation is performed by means of a numerical model developed in TRNSYS software allowing one to simulate dynamically the system and to assess its energy and economic performance. The goal achieved during the simulation of the system was to ensure at least 97% of energy demand from renewable sources. Moreover, a parametric analysis of the storage system is presented. It is found that payback period of the installation varies in the range between 11 and 15 years, for systems configurations allowing to satisfy 90–98% of the users energy yearly demand from renewables. The achieved results allows one to evaluate the feasibility of the proposed system from both an energy and economic point of view. • Island energy systems in Greece. • Hybrid energy system with both battery and hydrogen energy storage. • 97% reduction of energy produced from fossil fuels with 30% of energy curtailed. • Parametric study concerning sizes of the energy storage. [ABSTRACT FROM AUTHOR]

Nowadays, with the need for clean and sustainable energy at its historical peak, new equipment, strategies, and methods have to be developed to reduce environmental pollution. Drastic steps and measures have already been taken on a global scale. Renewable energy sources (RESs) are being installed with a growing rhythm in the power grids. Such installations and operations in power systems must also be economically viable over time to attract more investors, thus creating a cycle where green energy, e.g., green hydrogen production will be both environmentally friendly and economically beneficial. This work presents a management method for assessing wind–solar–hydrogen (H2) energy systems. To optimize component sizing and calculate the cost of the produced H2, the basic procedure of the whole management method includes chronological simulations and economic calculations. The proposed system consists of a wind turbine (WT), a photovoltaic (PV) unit, an electrolyzer, a compressor, a storage tank, a fuel cell (FC), and various power converters. The paper presents a case study of green hydrogen production on Sifnos Island in Greece through RES, together with a scenario where hydrogen vehicle consumption and RES production are higher during the summer months. Hydrogen stations represent H2 demand. The proposed system is connected to the main power grid of the island to cover the load demand if the RES cannot do this. This study also includes a cost analysis due to the high investment costs. The levelized cost of energy (LCOE) and the cost of the produced H2 are calculated, and some future simulations correlated with the main costs of the components of the proposed system are pointed out. The MATLAB language is used for all simulations. [ABSTRACT FROM AUTHOR]

Over the past decades, the penetration of renewable energy sources is growing at a significant pace on a global scale. In parallel, the utilization of renewables could possibly act as the basis for the transition to a Circular Economy, which aims to reduce the use of finite resources. Compared to other European countries, Greece has achieved a significant share of renewables in its' energy mix and in parallel promotes various policies aiming to accomplish zero-carbon emissions by 2050. An important element of this procedure is the broader acceptance of renewables by the public. This paper investigates this concept by capturing citizens' view on renewable energy sources along with the overall concept of Circular Economy in Greece. By implementing a questionnaire analysis, empirical findings capture the intention of citizens to further develop and invest on renewable energy. Besides, our analysis identifies that as education level increases, the willingness to pay more for renewables and their acceptance from the public increases, as well. Finally, empirical findings indicate that Greek citizens are aware of the concept and the benefits arising from Circular Economy, yet additional efforts need to be addressed for the growth of this concept in Greece. • The study captures citizens' view on RES and Circular Economy in Greece. • Participants are aware and sensitive on environmental and climate change issues. • Participants accepted the existence of RES and are willing to pay additional cost. • As the level of education increased, willingness to pay for RES also increased. • Additional efforts need to be addressed for the growth of Circular Economy in Greece. [ABSTRACT FROM AUTHOR]

Hydropower plays an essential role in Europe's energy transition and can serve as an important factor in the stability of the electricity system. This is even more crucial in areas that rely strongly on renewable energy production, for instance, solar and wind power, as for example the Peloponnese and the Ionian islands in Greece. To safeguard hydropower's contribution to total energy production, an accurate prediction of the annual precipitation is required. Valuable tools to obtain accurate predictions of future observations are firstly a series of sophisticated data preprocessing techniques and secondly the use of advanced machine learning algorithms. In the present paper, a complete procedure is proposed to obtain accurate predictions of meteorological data, such as precipitation. This procedure is applied to the Greek automated weather stations network, operated by the National Observatory of Athens, in the Peloponnese and the Ionian islands in Greece. The proposed prediction algorithm successfully identified the climatic zones based on their different geographic and climatic characteristics for most meteorological stations, resulting in realistic precipitation predictions. For some stations, the algorithm underestimated the annual total precipitation, a weakness also reported by other research works. [ABSTRACT FROM AUTHOR]

EU has set ambitious commitment to achieve low carbon energy and economy transition up to 2050. This low carbon transition means sustainable energy development path based on renewable energy sources and first of all should address the energy poverty vulnerability and justice issues. The main goal of the paper is to develop indicators framework for assessing low carbon just energy transition and to apply this framework for analysis how climate change mitigation policies in households targeting enhancement of energy renovation of residential buildings and promotion of the use of micro-generation technologies and other policies are affecting household's energy poverty and vulnerability in selected countries: Lithuania and Greece. This framework allows to assess three main dimensions of sustainable energy development: environmental, social and economic. The paper provides policy recommendations how to deal with just low carbon energy transition which means addressing energy poverty issues during moving to 100% renewables in power generation based on performed case studies. [ABSTRACT FROM AUTHOR]

New methods for state estimation are required due to the complexity of the topology of transmission and distribution systems, and the predictability in the management of prosumer dispatch. This paper describes a pilot project in Greece that, in accordance with OneNet's architecture, addresses the challenges of congestion and balancing management that system operators face due to the high penetration of renewable energy sources. The respective data requirements and the IT/OT environment are described, as well as the interconnections among the various modules and functionalities. Available resources of the grid's flexibility are identified, and the implementation of an integrated monitoring system based on efficient forecasting of volatile generation and demand is addressed. Congestion management and frequency and voltage control are in the center of interest of the demonstrator where, in close collaboration with system operators, respective network models are being developed. [ABSTRACT FROM AUTHOR]

The increasing penetration of renewable energy sources creates a challenge for the stability of current power systems due to their intermittent and stochastic nature. This paper presents the field results of an efficient demand response solution for controlling and adjusting the electric demand of buildings in an energy district through the activation of their thermal mass while respecting the occupants' thermal comfort constraints. This multilevel control approach aims to support grid flexibility during peak times by constraining the energy exchange with the grid and increasing the self-consumption of the district. The results show a great potential for increasing the self-consumption up to 37% for offices, as well as improving the indoor environment, based on real data collected from a case study in Greece. [ABSTRACT FROM AUTHOR]

The 2022 energy crisis augmented the European ambition for RES capacity expansion. However, beyond the issue of "how many" renewables, the research question that remains, is which capacity mixes achieve the emissions reduction, renewable integration, and energy autarky targets in a cost-effective way. This paper tries to answer this inquiry supported by two energy models and one decision support model. The analysis focuses on Greece, as an example country which opted for lignite phase out, turning to temporary heavy reliance on natural gas for power generation. The results indicate that even though from the energy and environmental targets' perspective, more wind turbines in the RES capacity mix yield better results, when incorporating the economic point of view, balanced wind and solar mixes enable the achievement of targets in a cost-effective way. The most cost-efficient mixes consist of 50–55% wind and 45–50% solar capacity, with cost per additional percentage of RES share in the generation mix, equal to 40 million €. Nevertheless, in order to materialize them in a timely manner, and limit the short-term dependency on imported gas, permitting simplification, tenders for large-scale projects and incentives for small-scale projects are needed to facilitate accelerated RES deployment. • A modelling framework allowing exploratory RES capacity expansion is presented. • Renewable energy sources and storage capacity mixes are explored. • Balanced wind and solar mixes achieve energy targets economically efficiently. • RES deployment pathways to 2030 based on different perspectives are analyzed. • Further policy action is needed to enable accelerated RES deployment. [ABSTRACT FROM AUTHOR]

Reducing the carbon emissions from hotels on non-interconnected islands (NII) is essential in the context of a low carbon future for the Mediterranean region. Maritime tourism is the major source of income for Greece and many other countries in the region, as well as hot-temperate and tropical regions worldwide. Like many NIIs, Rhodes attracts a high influx of tourists every summer, doubling the island's energy demand and, given the high proportion of fossil fuels in the Rhodian energy supply, increasing carbon emissions. Using the theoretical framework 'FINE', this paper presents the optimisation of a medium-sized hotel's energy system with the aim of reducing both cost and carbon emissions. By introducing a Photovoltaic (PV) net metering system, it was found that the carbon emissions associated with an NII hotel's energy system could be reduced by 31% at an optimised cost. It is suggested that large-scale deployment of PV or alternative renewable energy sources (RES) in NII hotels could significantly reduce carbon emissions associated with the accommodation sector in Greece and help mitigate climate change. [ABSTRACT FROM AUTHOR]

Salinity gradient energy (SGE) plants generate power from the mixing of salt water and fresh water using advanced membrane systems. In the Strymon River, under low-flow conditions, a salt wedge is formed, developing a two-layer stratified system, which could be used to extract SGE. In this paper, a novel study was implemented by coupling a 3D hydrodynamic model simulating the salt wedge flow, with the SGE model which assesses the net energy produced by a 1 MW SGE plant. Two scenarios were followed: (a) the optimal scenario, operating throughout the year by mixing salt water from the sea (38.1 g/L) and fresh water (0.1 g/L) from the river to produce 4.15 GWh/yr, and (b) the seasonal scenario, utilizing the salinity difference of the salt wedge. Results show that the daily net SGE production varies between 0.30 and 10.90 MWh/day, in accordance with the salinity difference (ΔSsw ~15–30 g/L). Additionally, a retrospective assessment (from 1981 to 2010) of the annual and seasonal net energy production was conducted. This analysis illustrates that the salt-wedge formation (spring to late summer) coincides with the period of increased regional electricity demand. In the future, the emerging SGE could serve as a decentralized renewable energy source, enhancing energy security in the region. [ABSTRACT FROM AUTHOR]

PHPS is a mature energy storage technology, leading to more efficient energy management and further integration of Renewable Energy Sources (RES). This paper investigates the implementation of such a system at Kastraki, Greece, combined with a second upstream reservoir with a total capacity of 10 hm3 and evaluates its efficiency. The position and the geometric characteristics of the second reservoir are determined with ArcGIS. When excess of energy exists, water is pumped from Kastraki reservoir and stored in the upper one. Otherwise, the stored water is used for energy production. The simulation is performed for 40 years with a monthly time step. Furthermore, another simulation for a typical day in July is conducted, when water and energy needs are increased. The system is evaluated in terms of covering the water supply and energy needs, as well as in terms of efficient energy management. Several results can be obtained, as follows: i) the reliability of the PHPS system for the coverage of monthly water supply and irrigation needs is 82.84 %. ii) The coverage of water supply needs for a typical day in July is 99.99 %. iii) The average monthly coverage of energy needs amounts to 83.86 %. [ABSTRACT FROM AUTHOR]

PHPS is a mature energy storage technology, leading to more efficient energy management and further integration of Renewable Energy Sources (RES). This paper investigates the implementation of such a system at Kastraki, Greece, combined with a second upstream reservoir with a total capacity of 10 hm3 and evaluates its efficiency. The position and the geometric characteristics of the second reservoir are determined with ArcGIS. When excess of energy exists, water is pumped from Kastraki reservoir and stored in the upper one. Otherwise, the stored water is used for energy production. The simulation is performed for 40 years with a monthly time step. Furthermore, another simulation for a typical day in July is conducted, when water and energy needs are increased. The system is evaluated in terms of covering the water supply and energy needs, as well as in terms of efficient energy management. Several results can be obtained, as follows: i) the reliability of the PHPS system for the coverage of monthly water supply and irrigation needs is 82.84 %. ii) The coverage of water supply needs for a typical day in July is 99.99 %. iii) The average monthly coverage of energy needs amounts to 83.86 %. [ABSTRACT FROM AUTHOR]

The European Union targets for 27% renewable energy share by 2030. At the same time, all new buildings should be nearly zero energy buildings from 2020 onwards. A major obstacle to these objectives is a combination of current economic stagnation and limited investors' confidence, which leads to low investment proportion. Despite many renewable energy technologies are already at a competitive level, the implementation rate in buildings is still low. In this paper, we focus on advances in efficient mechanisms to overcome non-technical barriers to the increase of renewable energy applications in buildings, such as Energy Performance Contracting (EPC). Tertiary sector holds a huge untapped potential for such applications, especially in Southern Europe. The Trust-EPC-South European initiative, implemented in six southern EU countries with a mix of beginner and intermediate energy service markets, aims at encouraging the financing of sustainable energy solutions in the tertiary sector, by creating a framework for standardization, assessment and benchmarking, thus improving trust and confidence in the financing parties. This paper presents three case studies in Greece, a Mediterranean family resort hotel, a resort and spa hotel and an office building. The installation of renewable energy measures, including photovoltaic systems, solar thermal systems and heat pumps, was examined and their EPC potential was rated, by using the described standardization and benchmarking methodology. Their economic savings range from 3 to 23% on yearly energy costs, at a discounted payback of 3–6 years, depending on the measure. A sensitivity analysis shows the impact of the variation of technical and economic parameters on the EPC projects feasibility. The standardization practice applied is expected to support the project actors in securing appropriate financing and eventually proceed with the renewable energy installations through the EPC. [ABSTRACT FROM AUTHOR]

The need for energy independence of small remoted islands, promote the exploration of renewable energy sources. Greek islands have rich wind potential and subsequently, the attention is being drawn to the use of wind turbines to meet their energy needs. However, the optimal location of wind turbines installation is the basis for the exploitation of high wind potential in combination with the current legislation framework. This paper presents a combined use of Multi‐Criteria Decision‐Making (MCDM) and Geographic Information Systems (GIS) for the evaluation of eligible sites for wind turbine installation in North Aegean island, in Greece. Criteria weights are estimated for three scenarios using the Analytic Hierarchy Process (AHP) for the illustration of the impact on the final design. The minimum distance from the main settlement of the island constitutes an extra constraint for the investigation of the capability of installing wind farms with the lowest possible energy losses due to power transmission via cables. In all scenarios, the prohibited zone corresponds to 27.9% of the total area of the island. Also, sites with high wind potential can be combined with lower altitudes and can give even more suitable locations for installation, reducing, thus, the installation cost. Economic‐oriented scenario appears to combine both low cost and larger surface area for installation. A sensitivity analysis is performed, for determining the impact of the criteria on the suitability of a site. It seems that new suitability maps are affected greater by the type of the chosen criterion rather than the weight. [ABSTRACT FROM AUTHOR]

The current paper reflects on the challenges faced by European islands with regards to electricity supply, focusing on an island area of major interest, i.e. the Aegean Sea region. In this context, the main problems related to the use of imported oil and the associated high electricity production costs are discussed, together with the prospects of increased exploitation of Renewable Energy Sources (RES). For the latter accomplishment, the main elements of an integrated energy solution are presented, comprising mature RES technologies and more novel aspects, corresponding to energy storage, Demand Side Management and intelligent Energy Management on the basis of advanced forecasting techniques. Moreover, insight and preliminary operational evidence are provided with regards to the application of such an integrated solution on the island of Tilos, in Greece, where the development and test-operation of a pilot smart microgrid and Hybrid Power Station were recently completed, in the context of the TILOS Horizon 2020 Program. • A short review of the electricity production status in Aegean islands is undertaken. • Challenges and prospects of RES in the Aegean islands' region are discussed. • We present novel elements that can support increased RES shares for Aegean islands. • We focus on the development and pilot operation of Tilos island smart microgrid. [ABSTRACT FROM AUTHOR]

• Examination of a typical classroom in Greece and its installed power for an artificial lighting profile from 1970 until today (type and number of luminaires, installed power per classroom, consumed annual energy kWh/m2). • Calculation of potential energy savings for customizing installed power LED with AC and DC supply aiming for the illuminance target values from the European Norm 12464–1, 2011. • Measurements of dimming curves of LED luminaires with AC and DC supply (consumed energy versus lighting output) and measurements of power of typical photosensors. • Estimated energy savings, CO 2 reduction and cost optimal analysis due to various scenarios (different luminaire technologies and daylight harvesting techniques). • Calculation of the final energy consumption for potential power supply from renewable energy sources using DC LED luminaires and photosensors. The energy consumption for the artificial lighting in school buildings is one of the main consumers of electricity. In Greece, there is a large number of school buildings with quite old lighting systems using luminaires with T8 and sometimes T12 fluorescent lamps and degradated translucent diffusers. Due to the economic crisis, the public sector failed to invest in LEDs and although daylight is adequate during the year, the adoption of control technology is rather slow. The paper, using a typical classroom of a Greek public school, examines a number of lighting technologies (with AC and DC supply) together with two daylight harvesting systems. The first one uses one stand-alone photosensor per luminaire while the second one sensor per control zone, in an effort to calculate energy savings and light adequacy. The dimming curves of the DC LEDs were measured along with the installed power of the photosensors. The results show that the existing 90.5 kWh p /m2 of annual lighting primary energy consumption can be reduced to 0.55 kWh p /m2. The maximum annual reduction of CO 2 emissions was 32.44 kgr/m2 for classroom areas, which is translated to 201929 tn for the whole country. It is evident that the path to Zero Energy School Buildings goes through the mandatory use of daylight controls. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The exergy analysis method constitutes an alternative but very important technique for the evaluation of the utilization level of thermal plants as well for the comparison of different conversion processes. The loss of exergy provides a figure of merit for the inefficiencies of a process and a measure of the quality of the different forms of energy in relation to given environmental conditions. In this paper, data from an experimental geothermal drill in the Greek Island of Nisyros, located in the south of the Aegean Sea, have been used in order to estimate the maximum available work and the efficiency of a potential power plant. Different methods for estimating the exergy term are used and several types of conversion efficiencies have been calculated in order to obtain a more complemented view of the analysis. Overall, a system exergetic efficiency of 41% and a thermal one of 12.8% have been resulted supporting technical feasibility of the proposed geothermal plant. [ABSTRACT FROM AUTHOR]

The decision-making process regarding the choice of alternative energy technologies is multidimensional, made up of a number of aspects at different levels, economic, technical, environmental and social. This paper uses a multicriteria decision making model, PROMETHEE II, to determine the best fuel mix for electricity generation in an isolated Greek island, Lesvos. Having analyzed the energy profile of the island, a set of 7 energy policy scenarios are determined and assessed against economic, technical, environmental and social criteria. The energy policy scenarios include the use of conventional fuels, wind energy and natural gas, in its liquid form, liquefied natural gas (LNG). Weighting of criteria is carried out according to three different perspectives, each one focusing on sustainability, economic and environmental/social benefits. Two sensitivity analyses are performed taking into account the fluctuations of the electricity demand and the fluctuations of the fuel prices. [ABSTRACT FROM AUTHOR]

This virtual special issue published in Renewable and Sustainable Energy Reviews contains 25 high-quality selected extended papers presented at the HERAKLION 2019 7th International Conference on Sustainable Solid Waste Management held in Heraklion, Crete in Greece from 26th to June 29, 2019. The articles published in this special issue focus on recent developments in sustainable waste-to-energy systems and waste management practices and highlight the critical challenges and potential solutions. The editorial paper aims to give a brief overview of the key findings and future perspectives proposed in these 25 selected papers. It is worth noting that although the articles presented in this special issue covered a wider range of topics, they are categorized into five categories. These include the latest developments in 1) waste-to-energy technologies, 2) biofuels and bioenergy, 3) waste valorization, 4) emerging renewable and sustainable energy systems, and finally, 5) biorefineries and circular economy. • Twenty five high quality peer-reviewed papers were selected from HERAKLION 2019 Conference. • The mian theme of sustainable waste-to-energy systems catogorised into five topics. • It will support advancement of waste-to-energy technologies and circular economy. [ABSTRACT FROM AUTHOR]

A key factor hampering the delivery of high energy performance renovations in buildings is the under-qualification of the construction sector's workforce with regard to energy efficiency and renewable energy sources systems. Towards this direction, this paper proposes an integrated methodological framework, determining measures for the case of Greece, which are delivered in the form of a national qualification roadmap. These measures aim to enhance the qualifications of the blue collar workers and generally empower the Greek construction sector. They also facilitate the adherence of Greece to the European Energy Efficiency and Renewable Energy Sources Directives and support the attainment of the national energy objectives for 2020. The methodological framework is initiated with the analysis of the status quo of the Greek building sector and the skills and qualifications gap of the workforce, as well as the identification of the corresponding barriers that impede growth. Subsequently, a number of diverse measures are proposed and evaluated, using a synergy of decision analysis and evaluation methods. The measures that are assessed as of high priority are afterwards specified to concrete actions. Throughout the whole modular procedure, multiple relevant national bodies were actively engaged via transparent consultation procedures and multilateral discussions. Finally, 44 acknowledged organisations declared their endorsement to the roadmap by signing an official letter. [ABSTRACT FROM AUTHOR]

This paper uses monthly data from Aug. 2004 to Feb. 2014 and employs the Autoregressive Distributed Lag bounds test approach to study the short and long-run relationship of renewable and non-renewable electricity with economic growth in Greece. Dummies reveal most of the major energy policy adaptations taking place in Greece to overcome the economic crisis and reach stipulated renewable energy targets. Results show that in the short-run, fossil sources play the baseload role in electricity production and there is a clear substitution effect between sources, while in the long-run, fossil sources contribute to the development of renewable energy sources as backup energy. [ABSTRACT FROM AUTHOR]

This paper investigates numerically the deep renovation of a multi-family building in Greece to reduce dramatically its energy demand and also to incorporate renewable energy sources, rendering it a positive one; thus in position on an annual basis to offer net electricity to the grid. The examined building has 8 apartments of 75 m2 floor area each and is located in Moschato, a suburb of Athens in Greece. The goal of the present investigation is to determine the energy savings, but also to calculate the financial and environmental benefits through a life cycle analysis. The energy simulation of the building is conducted on annual basis by using a novel and detailed dynamic software tool (INTEMA.building), which is developed in the Dymola environment using the Modelica modeling language. This tool makes possible the detailed simulation of both passive and active systems in the building environment. Furthermore, it includes the control of the energy systems and can provide accurate enough results, encompassing detailed numerical models for the systems investigated, accounting for an adjustable time step of the dynamic analysis. According to the calculations, the proposed retrofitting scenario can achieve a reduction of the heating loads by 93% and of cooling loads by 78% respectively. The electrical demand for domestic hot water can be decreased by about 79%, while the electricity demand for appliances and lighting by about 60%. In terms of specific thermal needs, the specific heating demand can be reduced from 151.5 kWh/m2 down to 10.7 kWh/m2, while the cooling specific demand from 112.6 kWh/m2 to 24.4 kWh/m2. Moreover, it is calculated that the reduction in the primary energy demand after the renovation can be up to 88%, with the building providing around 5.3 MWh of net electricity to the grid on a yearly basis through a net-metering connection. Finally, the life cycle cost analysis indicated 622 k€ savings and specific CO 2 avoidance per renovated floor area in the range of 2.64 tons CO 2 /m2. • A new tool for dynamic simulations of buildings and energy systems is presented. • A holistic renovation scenario of a multi-family Greek building is investigated. • The primary energy reduction after the renovation was found at 88%. • The renovation payback period is 3.8 years and the specific lifecycle gains 1037€/m2. • The specific CO 2 avoidance was calculated at 2.64 tons CO 2 /m2. [ABSTRACT FROM AUTHOR]

Abstract: An initiative namely “SAVE or EXOIKONOMO” is implemented in Greece and includes development and implementation of municipal investment plans for sustainable energy development in urban areas. However, a part of the investments’ funds is covered by the government and most of the municipalities have serious difficulties in successful participation in this initiative. As a result, further efforts and “new” financial mechanisms are necessary in order to support the implementation of sustainable energy investments in urban areas. The scope of the current paper is to investigate the potential of implementing “JESSICA” as a complementary financing mechanism in the context of the development of sustainable energy investments. In specific, the successful financing of the strategic plan by Rhodes Municipality in Greece for improving energy efficiency is analyzed in this paper. Based on the results, the utilization of JESSICA for financing sustainable energy investments in urban areas of municipal authorities seems to fit well into the overall requirements of JESSICA as a financing mechanism of integrated urban development. [Copyright &y& Elsevier]

Abstract: This paper examines the integration of new sources of renewable energy into the power systems in Europe—challenges and possible solutions, application of wind power prediction tools for power system operation, new tasks that create new solutions for communication in distribution systems, wind power in Greece, integration of dispersed generation in Denmark, wind power in The Netherlands, EdF and distributed energy resources in France, and new renewable sources in Italy. The paper also examines the European Commission Technology Platform’s vision paper on Electricity Networks of the Future that was published in January 2006. In this respect, drivers towards Smart Grids, Grids today, and key challenges for Smart Grids of the Future are critically assessed. [Copyright &y& Elsevier]

A self-sustained, zero-CO 2 emission RES-H 2 Hybrid Energy System (HES) was developed at Lavrion Technological & Cultural Park (Attica, Greece) to cover electric power, heating/cooling loads (tri-generation) of an office building located in its premises. The primary energy is harvested from RES and directly applied to cover contingent loads, whereas the excess energy is converted to hydrogen to be used as energy storage system and thus as a green fuel to cover the building heating needs through direct combustion or to produce combined heating and electricity by means of fuel cells. In this study, the performance of the functional RES-H 2 HES is evaluated as well as its impact by applying the methodology of Life Cycle Assessment. HES resulted in the reduction of Global Warming Potential, Acidification Potential and Photochemical Oxidant Formation by 40%, 42% and 35%, respectively, compared to the exclusive use of Greek energy grid mix for electricity. • Life Cycle Assessment of a hybrid RES-H 2 Hybrid Energy System developed in Greece. • Hybrid Energy System reduced GWP by 40%, compared to the use of GR-energy grid mix. • AP is decreased on Hybrid Energy System by 42%, compared to the GR-energy grid mix. • POF of Hybrid Energy System was 35% less compared to the use of GR-energy grid mix. • Environmental impact of PVs was 5 times higher, compared to WTs. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to prove, according to our inventory that, beyond the horizon of the era of transition and economic crisis of nowadays, Greece is a real "Archimedean Screw Hydropower Development Terra Incognita", a country generously blessed with water, having an important hydropower potential. This inventory shows that the unexploited small hydropower capacity of Greece, including Archimedean possibilities, is approximately 3.500MW. The significant untapped small hydrodynamic potential demonstrates the important role of Pindos Mountain Range, controlling the annual rainfall difference between the North-Western and the Eastern Greece. The climatic and topographic conditions in Greece favor the development of many small Archimedean screw hydropower stations, harnessing the potential of a large number of small and big watercourses crossing mainland of the country. Pleiades of very promising Archimedean small hydro screw plants, having inclined and horizontal axis hydrodynamic rotors, could be installed following two hydro development axis (spears). [ABSTRACT FROM AUTHOR]

The key policy analyzed in this paper, is the achievement of a significant decarbonization of the Greek Energy System by the year 2050 through the decarbonization of the two sectors presently responsible for the highest levels of greenhouse gas emissions (GHG) emissions, namely power and transport. The objective is to reduce GHG emissions by 2050, through the maximization of renewable energy sources (RES) penetration in electricity, with a simultaneous intensive electrification of the transport sector and the electrical interconnection of non-connected islands. An important parameter considered in the present work is that expansion planning of power systems under environmental constraints leads to a rather complex techno-economic analysis involving large scale penetration of Renewable Energy Sources. The penetration level of variable renewable electricity is subject to a number of restrictions implied by the need for (a) storage capacity to decrease the energy curtailment which can occur when the customer load is low and RES electricity generation is high (b) fast reserve capacity to deal with variations of variable RES or combined heat and power (CHP) electricity generation (c) transmission system expansion related to the penetration of areas with high RES potential. New methodologies are developed and a number of novel scenarios are formulated in conformity with the European energy strategy towards 2050. [ABSTRACT FROM AUTHOR]

This paper reviews the state of liquid biofuels in Greece and presents the current situation in production and research. The first part presents the production potential in terms of cultivated crops along with the industrial activity on biofuels and their distribution in the country. In the second part, the research activities are discussed. It is shown that the Greek biofuel potential is significant, although some problems in the allocation of the fuel resulted in severe constraints to efficiency. Research on the optimization of biodiesel properties and on the development of 2nd generation biofuels as well on the assessment of their impacts on engine performance and emissions is remarkable and promising. [ABSTRACT FROM AUTHOR]

As more economies are transitioning away from fossil fuels for their electricity production and towards greener alternatives, many socioeconomic implications of this shift remain actively debated. The present paper attempts to assess the economic impact of investments in renewable energy sources (RESs) for Greece and whether the broader effects of this transition can offset the negative impact that will occur due to the targeted phase-out of lignite plants by 2028, which constitute the predominant power source for Greece. Our methodological approach builds on input–output analysis and the creation of composite RES industries for the estimation of the net effects of a series of monetary shocks that correspond to Greece's phase-out investment plan, utilizing the most recent national input–output tables and satellite structural business statistics. We focus on the structural effects of these shocks on a series of socioeconomic indicators, including GDP, employment, wages, government income (through taxes), and capital formation. The results indicate that even though lignite power production still provides a significant contribution to the Greek economy, investing in renewables presents a significant opportunity for value added and job creation. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the study was to present the current status of the electrical energy market, energy legislation, green house gas emissions, energy consumption trends and future prospects of sustainable development in Greece. The study described current issues relevant to the renewable energy sources (RES) such as the climatic factors that affect the penetration of RES into the Greek energy mix, the current regulation status, the barriers and evaluation of their contribution in the energy balance. The study also investigated the increasing power demand, emissions and energy trends in the residential sector in Greece. The paper evaluated the current status of the building stock, RES and the future energy related prospects of the Aegean Sea islands. The islands were categorized based on energy production cost, heating degree days, building characteristics and natural resources to identify islands with higher and lower renewable energy potentials. The study revealed that the islands with the higher potential energy savings in the residential sector are Lesbos, Lemnos, Samothrace, Chios, Andros, Patmos, Kea and Kimolos while at the same time, Rhodes, Naxos, Amorgos, Syros, Ios and Kythnos are those islands that present the lower potential. The study will help to propose action plans and implementation strategies in terms of residential renewable energy applications in non-grid interconnected islands in Greece. [Copyright &y& Elsevier]

Abstract: In the present paper a Linear Programming (LP) methodology for the city of Athens, Attica region is implemented trying to identify the energy supply levels based on the energy use, aiming to determine the optimal way for the energy needs to be covered. The final aim was to find the best solution/s to meet the (metropolitan) city''s energy needs using Renewable Energy Sources (RES) and additionally implement a techno-economic analysis through a developed tool, in order to find which RES should participate in the city''s energy system examining different scenarios focusing not only on the projects'' economical success but also on minimizing the cost for the society. [Copyright &y& Elsevier]

Abstract: Renewable energy sources are called to play an important role as regards the increasing energy demand worldwide. In particular, the need to address the problems created by the oil crises has distinguished the importance of renewable energy in economic development. Biomass is recognized as one of the most important renewable energy sources that can contribute decisively to the energy needs of modern society and the environment protection, in both industrialized and developing countries. A very important source of biomass is wood and especially fuelwood. In Greece, because of the economic crisis, there is an increased consumption of fuelwood, especially in rural areas. In this paper, using a questionnaire and descriptive statistics and logistic regression analysis, we explore the determinants of fuelwood consumption in a rural area, in order to propose appropriate policies for the efficient supply of the market. [Copyright &y& Elsevier]

Abstract: This paper formulates and implements an integrated approach for estimating the employment benefits associated with the exploitation of renewable energy sources (RES) in the power sector. It builds up on well-known techniques and makes all the necessary modifications in order to take into account the specific conditions of the RES market. More specific, the proposed approach exploits the input–output methodology for estimating the direct, indirect and induced employment effects associated with the energy technologies in question and the “opportunity cost of labour” approach for expressing these effects in monetary terms. This framework has been implemented to estimate the employment benefits resulting from the development of different RES technologies in Greece, taking into account both the construction and operation phases of the relative projects. The results of the analysis clearly show that the exploitation of RES in the Greek power sector presents significant employment benefits, which are at the same order of magnitude or in several cases even higher compared to the corresponding benefits attributed to the operation of fossil-fueled power plants (e.g. lignite and natural gas). Therefore, the fulfillment of the national target for increasing the penetration of RES into the Greek power sector from approximately 12% today to 40% in 2020, will contribute, apart from the significant environmental improvements, to the overall economic development and the increase of the employment. [Copyright &y& Elsevier]

Abstract: The capacity expansion planning is a crucial process taking into account multiple aspects and various parameters of the examined power sector in order to optimally satisfy the future electricity demand. In the case of Greece, the long-term energy planning of the electricity supply sector faces a lot of challenges deriving from the peculiarities and geomorphology of the country mainly referring to the large number of islands. This paper explores the feasibility and the consequences of interconnecting Greek islands to the mainland grid by establishing two alternative scenarios of least cost electricity planning for the period 2009–2020. Namely, the reference scenario assumes isolated electric systems of islands and is compared against the alternative option of their interconnection to the mainland. The main purpose of the present study is to illustrate the great importance of islands’ interconnection on the development of renewable energy sources (RES) to generate electricity while pointing out the consequent economic and environmental benefits. [Copyright &y& Elsevier]

Abstract: This paper deals with the feasibility of RES-based systems for electricity supply in four different Greek Islands. Three specific typical loads were selected to be covered, where the grid connection was considered as optional. An optimization procedure in terms of energy efficiency and economical feasibility has also been applied, using the HOMER software for the energy part and a hand-made calculation procedure for the financial aspects. It is found that an off-grid project is not economically feasible and the grid connection is necessary only for the sale of excess electricity (not as a backup source). Finally, the relationship between environmental potential and produced energy is found to be linear, with almost constant behaviour for solar systems. [Copyright &y& Elsevier]

Abstract: In areas lacking substantial freshwater resources, the utilisation of alternative water sources, such as desalinated seawater and reclaimed water, is a sustainable alternative option. This paper presents an optimisation approach for the integrated management of water resources, including desalinated seawater, wastewater and reclaimed water, for insular water deficient areas. The proposed mixed integer linear programming (MILP) model takes into account the subdivided regions on the island, the subsequent localised needs for water use (including water quality) and wastewater production, as well as geographical aspects. In addition, the integration of potable and non-potable water systems is considered. The optimal water management decisions, including the location of desalination, wastewater treatment, and reclamation plants, as well as the conveyance infrastructure for desalinated water, wastewater and reclaimed water, are obtained by minimising the annualised total capital and operating costs. Finally, the proposed approach is applied to two Greek islands: Syros and Paros-Antiparos, for case study and scenario analysis. [Copyright &y& Elsevier]

Abstract: This paper aims at providing useful insights into tourists’ preferences for choosing to stay in hotels equipped with Energy Saving Installations (ESI) and Renewable Energy Sources (RES). Factors related to these decisions were studied through 2308 face to face interviews taken at the departure terminals of the two international airports of Crete, Greece. Results show that 86% of the respondents would prefer to stay in hotels equipped with ESI, and 87% in hotels with RES, rather than staying in hotels of identical quality which do not have either ESI or RES. Furthermore, the percentages of respondents who would be willing to pay fee surcharges for a hotel equipped with ESI or RES are 75 and 77%, respectively, as compared to hotels of identical quality which do not have either ESI or RES. Tourists from countries with high energy awareness, prove to be more willing to choose to stay at and pay for hotels with ESI and RES. [ABSTRACT FROM AUTHOR]

Abstract: Most medium and small islands of the Aegean Archipelagos face serious infrastructure problems, strongly related with the limited electrical energy available at extremely high cost. On the other hand, the area is characterized by very high wind speeds and abundant solar energy, thus the exploitation of the available renewable energy sources (RES) may significantly contribute to the fulfillment of the local societies energy demand at minimum environmental and macroeconomic cost. However, the stochastic availability of wind energy and the variable availability of solar energy, the daily and seasonal electricity demand fluctuations, as well as the limited local electrical network capacity result in serious restrictions concerning the maximum renewable power penetration. In this context, the present paper investigates the possibility of creating a combined electricity generation facility based on the exploitation of wind or/and solar potential of an area as well as on the utilization of an appropriate energy storage configuration in order to replace the existing thermal power stations with rational investment requirements. For this purpose, the major parameters of the proposed integrated configuration are firstly calculated and its financial viability is accordingly analyzed. One of the main targets of the proposed solution is to maximize the RES exploitation of the area at a minimum electricity generation cost, while special emphasis is given in order to select the most cost-efficient energy storage device available. According to the results obtained the proposed solution is not only financially attractive but also improves the quality of the electricity offered to the local communities, substituting the expensive and heavily polluting existing thermal power stations. [Copyright &y& Elsevier]

Abstract: For Greece the target set by the Kyoto Protocol foresees an increase of greenhouse gases (GHG) emissions by up to 25% for the period 2008–2012, always with respect to 1990 levels. Apparently it is hard to achieve this target, because the current trend of emissions leads roughly to doubling the rate of increase, than to reducing it. Consequently, further support actions are required, in order to enhance the effort needed so that the country will manage to fulfill its commitments. The present paper aims at the evaluation of the existing situation and the suggestion of further actions required in the energy sector, and particularly in the exploitation of renewable energy technologies (RETs), in order to achieve the obligations that Greece has undertaken as far as the reduction of GHG emissions is concerned, in accordance to the European and international Greek commitments. The current analysis is based on the recent available data from official Greek institutions such as the relevant Ministries, the Managing Authority of the Operational Programme Competitiveness and related European institutions. Based on the results of the current study the implementation of RETs’ investments for the period 2000–2006 is estimated to cover, at best, 50% of the share corresponding to the energy sector for the national target of reducing GHG emissions. In order to achieve to a full extent the target up to 2010, an additional investment cost of some 740M€ will be needed. [Copyright &y& Elsevier]

Abstract: The utilisation of renewable energy sources, and wind energy in particular, can be described in Greece as a story of high expectations, intense initial entrepreneurial interest, delays in the start-up phase of projects and, some times, disappointments during the implementation procedure. Still, the current situation gives reasons for some optimism. This paper provides a review of the present technological background in wind generators, as found in the Greek market, as well as a detailed analysis of the legislative framework. Moreover, it aims to analyse the development of the process of granting investment and production permissions and their implementation since 1999. Thus, it is possible to identify the main reasons for the problems that occurred since the liberalisation of the electricity market and to account for the interest in wind energy. Finally, comments and proposals are formulated concerning the hidden barriers, the pertinent problems and the promising perspectives of the use of wind energy in Greece. [Copyright &y& Elsevier]

Abstract: Agricultural and animal wastes constitute a high proportion of biomass in Greece, and are able to play an important role towards the satisfaction of heat and/or energy and related material supply, with respect to the environmental protection targets. This paper describes pyrolysis, gasification and combustion, as a potential agricultural and animal waste exploitation method, and presents a comparison between those treatments when utilized as a source for renewable energy. The aim of the present work was to strengthen the interest in agricultural and animal waste potential for energy production in Greece, through a methodology for the feasibility of utilization of those kinds of wastes as renewable energy resources. A combination of technical, economic and environmental issues is presented here, and focus on the benefits that thermochemical conversion is able to offer, either in investigation or in future technological application for alternative exploitation methods of animal and agricultural wastes. [Copyright &y& Elsevier]

This paper presents the results of a thorough planning investigation carried out by the Transmission System Operator (TSO) and the Distribution Network Operator (DNO) in Greece in order to study the interconnections of the Aegean Islands with the mainland power system. The feasibility of interconnecting islands is based on the need for a reliable power supply to isolated and autonomous islands, reducing the operating costs of the power generation system through the withdrawal of high-cost oil-fired generating units, and the further ability to increase renewable energy source (RES) penetration in the country's energy mix, according to directions imposed by the National Energy and Climate Plan. Among the alternative topologies and interconnection technologies considered, the final selection of the interconnection scheme selected for inclusion in the development plans of TSO and DNO was based on their detailed comparative evaluation, considering financial and other technical criteria. [ABSTRACT FROM AUTHOR]

In alignment with the European Union's legislation, Greece submitted its final 10-year National Energy and Climate Plan (NECP) in December 2019, setting more ambitious energy and climate targets than those originally proposed in the draft version of the document. Apart from higher penetration of renewable energy sources (RES), the final NECP projects also zero carbon use in power generation till 2030. Although decarbonization has long been regarded beneficial for economies that base their energy production on coal, as it is the case with Greece, the macroeconomic and societal ramifications of faster transitions to carbon-free economies remain highly unexplored. Under this context, in this paper, we soft-link energy models, namely Times-Greece and Primes, with a macroeconomic model, namely Global Trade Analysis Project (GTAP), to measure the effects of the final and draft NECPs on the Greek economy and evaluate the impact of higher decarbonization speeds. We find that the faster transition scenario displays both economic and societal merits, increasing Gross Domestic Product (GDP) and household income by about 1% and 7%, respectively. [ABSTRACT FROM AUTHOR]

This paper addresses issues surrounding sustainable development policies and local environmental movements in non-developed rural regions. Using primary and secondary data sources, it documents that local mobilization against geothermal energy development on the Island of Milos (Greece) in the late 1980s can only be viewed as a clash stemming from supralocal decisions to allocate or restrict access to ecosystems by groups. This evidence supports Schnaiberg's political economy perspective on environmental conflict. Theories which view the state as facilitator of economic growth and social legitimator of its citizenry can adequately explain the roles of both the national and local state in this case study. The Milians mobilized against a ‘sustainable development’ project in order to protect the local environment and thus sustain their resource base. The role reversal, therefore, between developers and the indigenous population indicates the need to reassess the sustainability potential of geothermal and other renewable sources of energy. [ABSTRACT FROM AUTHOR]

Solar irradiation is a major contributor to renewable energy sources and its utilization is vital for designing a sustainable and green energy network. Greece is a country with high solar potential and thus the exploitation of solar irradiation in this country is an urgent need in order to reduce fossil fuel utilization. Moreover, the increase in solar energy exploitation will lead to the mitigation of environmental policy goals for cleaner energy production processes. To date, Greece exploits solar irradiation mainly with flat plate collectors for low-temperature heating applications and with photovoltaics, while there are no installations including concentrating solar systems although they are attractive technologies. The objective of the present review paper is to demonstrate and to discuss the present steps in the domain of solar concentrating systems in Greece, as well as to suggest future steps aiming to increase the solar energy contribution in this country. More specifically, this work includes studies about parabolic trough collectors, linear Fresnel reflectors, compound parabolic concentrators, solar dishes, solar tower and concentrating thermal photovoltaics. The existing situation regarding solar energy utilization in Greece is collaborated and predictions about future perspectives are provided. It is concluded that although much research interest has been devoted to installations in Greece, no real solar concentration systems are currently in operation. Moreover, the existing studies indicate that solar concentrating systems lead to sustainable and viable investments with acceptable payback period time in the range of 5–7 years. As a result, it is suggested that this is the time to proceed in the next step of the development of real solar concentrating installation in Greece. • All the solar concentrating systems for the Greek climate are included in this review. • Applications for power, refrigeration, heating and polygeneration are presented. • Up today, many theoretical studies have been conducted for Greek solar systems. • In the future, there is a need for real applications and experimental studies. • The examined cases are found to be viable for the climate conditions of Greece. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to investigate the use of the site "Potamon" Dam in the Prefecture of Rethymnon, Crete island, Greece, as a "virtual" renewable electricity supply of a pumped storage plant (PSP) in order to save and exploit the maximum possible part of the rejected wind energy of the autonomous power system of the Crete island. Taking into account the annual time series of the rejected power of the Crete power grid, the present research work targets the optimal configuration of the proposed PSP power station, including the sizing of its individual components as well as the determination of the capacity it could guarantee in order to be economically viable. The rejected electric energy from the actually operating wind farm production, which is not possible to be absorbed by the grid of Crete due to its stable operation limitations, could be absorbed by the here proposed pump storage plant (PSP) and converted to hydraulic energy. This can be achieved by pumping the water from the lower reservoir, which is the existing reservoir of the site "Potamon" Dam, with a storage capacity of about 22.5 million m3, up to the upper reservoir, which must be constructed accordingly. For the proposed PSP's optimal size determination, established financial indices are used as an evaluation criterion for an investment life cycle of 25 years. The proposed PSP optimization is based on the dynamic mathematical model of the simulation results of the PSP's hourly operation when incorporated in the Crete power grid for a whole year, performed in the Matlab 2016b computational environment (The MathWorks, Inc., Natick, MA, USA). The results of this research demonstrate the PSP's technical feasibility and determine the PSP's optimal CAPEX and the PSP's whole life-time financial indicators in order that the whole investment be viable. Furthermore, the appropriate selling prices of the electricity produced from the proposed PSP were determined to achieve the PSP's financial viability. The results comprise the key elements to prove the necessity for the establishment a.s.a.p. of the appropriate legal framework in order to have authorization to exploit the rejected RES (renewable energy sources) electric energy or the major part of it through PSPs, in priority in both the non-interconnected, as well as the interconnected power systems. [ABSTRACT FROM AUTHOR]

• A modular demand-side management model including all important aspects of end-use. • Quantifying benefits of demand-flexibility for consumers in the residential sector. • Scenarios of full electrification of heating/cooling in the residential sector. • Benefits of flexibility if integrated in the retailing operations of utilities. • Policy recommendations towards a power sector based on decentralized generation. Increasing shares of renewable energy sources and managing total demand are considered pivotal for energy transitions that fundamentally re-envisage the electricity system. A key challenge of such transitions is integrating and absorbing increased shares of non-dispatchable renewable energy sources, without jeopardizing the security and the reliability of the electricity system. To this end, key solutions include the introduction of demand-side management. However, so far, demand-side management modeling at the building sector has been proven challenging, as existing models are not flexible enough to incorporate a wide set of modeling features and guiding principles, while including all important aspects of end-use. This paper presents a new dynamic high-resolution demand-side management model which brings together all the key features and guiding principles of demand-side management modeling. The novelty of the model lies mainly in its modularity, as the main modeling framework is decomposed into individual modules, hierarchically dependent on components embodying standards and design rules, allowing for multiple configurations and computational efficiency. To demonstrate its applicability the model was used to explore benefits of demand-flexibility for consumers in the residential sector in Greece. Simulation results showed that the flexibility to increase self-consumption can be brought to the Greek electricity sector without a need for significant changes in the current market design, and for consumers to sacrifice thermal comfort and energy services. [ABSTRACT FROM AUTHOR]

The use of renewable energy sources instead of conventional energy sources is at the core of policy actions to reduce dependency on fossil fuels worldwide. As a result, especially during the last decade, the cost of renewable energy has significantly decreased, enriching renewable energy cost-competitiveness. Due to the spatial nature of renewable energy sector-related decisions, the synergy of geographical information systems (GIS) and Multiple Criteria Decision Analysis (MCDA) models can enrich the quality of the related decisions given their ability to effectively support land management considerations. Moreover, their implementation significantly enriches the performance of the traditional capital projects evaluation methods (CPEM) by providing physical data to the sizing process in a quick and accurate manner. Thus, decision-making frameworks that combine GIS-based suitability analysis with traditional financial evaluation techniques can significantly enrich the planning phase to achieve efficient installations in terms of required area reduction, power generation maximization and local characteristics examination. With respect to the realization of wind energy exploitation projects, the paper at hand proposes a framework capable of expanding the use of the traditional GIS-based derived suitability index to establishing portfolios. Moreover, the proposed framework is enriched by robust analysis using Monte Carlo Simulation (MCS), which provides significant insights regarding the stability of the derived portfolios and the projects that they comprise. The proposed framework is illustrated through a case study in the Thrace region in northeastern Greece. • Wind farms portfolio formation combining spatial and nonspatial attributes. • Simulation provides computational efficiency in modeling uncertainty and imprecise knowledge. • Portfolio Selection Index provides a measure of the derived portfolios stability. • Portfolio Alternative Selection Index measures the eligibility of the examined wind farms. [ABSTRACT FROM AUTHOR]

The significant penetration of renewables, in the Hellenic electricity system, during the last 12 years, was based on feed-in tariff-supporting schemes, according to the compliance to European Directives. The characteristics of this penetration are presented and analyzed in this paper based on real data. Photovoltaics, wind parks, hydroelectric plants, biomass-driven plants, and cogeneration systems are examined. The cost of the feed-in tariff incentives is qualified and analyzed. Simple but effective models are proposed to describe renewable seasonal variation: (a) A simple cosine model adequately describes the seasonal performance of various renewable technologies in terms of capacity factor; (b) a smart seasonal model based on the separation between winter and summer consumption activities (both following normal distributions) adequately describes the electricity consumption profile. The predicted values of renewable shares using the proposed models were also validated with historical data. Thus, the applied models can be used to forecast renewable shares under different penetration scenarios. [ABSTRACT FROM AUTHOR]