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The continuous increase in energy demand has led to the gradual depletion of fossil fuels and the corresponding environmental degradation. As a result, the implementation of energy efficiency measures, as well as the integration of Renewable Energy Sources systems, are a challenge on the road towards Nearly-Zero Energy Buildings. Within the framework of this study, an extensive literature review was carried out on the existing Photovoltaic/Thermal collector technologies, their energy, environmental and economic efficiency. Furthermore, a solar combi system with photovoltaic/thermal collectors installed in a residential building was studied. The system was evaluated for its energy and environmental efficiency. Finally, the results in terms of thermal efficiency and carbon footprint were compared with those of a solar combi system with a flat plate collector. [ABSTRACT FROM AUTHOR]

In the coal phase-out era, achieving sustainable mine closure is significant and prioritizes targets for the mining industry. In this study, the already closed lignite mine of Kardia, North Greece, is investigated, where the mine void left is naturally filled with water. The viability of different repurposing land uses is evaluated, and the natural water level development inside the mine pit is investigated concerning its future uses. The potential for solar photovoltaic (PV) panels developed on mining land and its surrounding area is evaluated in combination with the application of pumped hydro storage (PHS) technology, utilizing pit lake water. Except for electricity system planning, other end-uses that offer multiple, mutually reinforcing and lasting benefits are investigated, such as recreation parks, terrestrial wildlife, aquaculture and agriculture. All repurposing scenarios are evaluated with regard to the spatiotemporal evolution of the lake, by generating forecasts of the dependent variables (rainfall and temperature) via linear (autoregressive integrated moving average) and non-linear (artificial neural network) models. The prediction of pit lake natural development redefines the new land use layout and the land repurposing decisions. This is essential for strategic planning, considering the Greek lignite mining industry's priority regarding transitioning from the current coal-based electricity to renewable energy sources (RES) technology. [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]

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]

The proactive sustainable management of scarce water across vulnerable agricultural areas of South Europe is a timely issue of major importance, especially under the recent challenges affecting complex water systems. The Basin District of Thessaly, Greece's driest rural region, has a long history of multiple issues of an environmental, planning, economic or administrative nature, as well as a history of conflict. For the first time, the region's key-stakeholders, including scientists and policymakers, participated in tactical meetings during the 19-month project "Water For Tomorrow". The goal was to establish a common and holistic understanding of the problems, assess the lessons learned from the failures of the past and co-develop a list of policy recommendations, placing them in the broader context of sustainability. These refer to enhanced and transparent information, data, accountability, cooperation/communication among authorities and stakeholders, capacity building, new technologies and modernization of current practices, reasonable demand and supply management, flexible renewable energy portfolios and circular approaches, among others. This work has significant implications for the integrated water resources management of similar south-European cases, including the Third-Cycle of the River Basin Management Plans and the International Sustainability Agendas. [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]

With the increase in the complexity of the topology of transmission and distribution systems, associated with the predictability in the management of the dispatch of prosumers, new techniques for state estimation, and application of metaheuristics are necessary. In the current work a pilot project in Greece that addresses the difficulties of congestion and balancing management that system operators face in the renewable energy sources era, in accordance with the OneNet's architecture is described. Available resources of grid's flexibility are identified, and the implementation of an integrated monitoring system based on weather conditions with an energy control and dispatch system in the Greek electricity grid is addressed. The document suggests that flexibility resources will derive through predictions that have been improved and efficient forecasts from increased spatial resolution Numerical Weather Predictions and integration of Artificial Intelligence preventing the power system of entering dangerous topological or operational states. [ABSTRACT FROM AUTHOR]

Research activity in the field of combined cooling heating power (or trigeneration) systems with high renewable energy source (RES) contributions has increased rapidly over the last few years, in line with the European Union legislation about energy communities. However, technical challenges arise regarding the synergetic, sustainable and optimal integration of RES in local energy systems. In the present study, the operation of a trigeneration system located in the student residences of Democritus University of Thrace in Greece is examined. The system involves a combination of highly promising renewable and storage technologies, including solar thermal energy and biomass for heat generation, hot water tanks for thermal energy storage, absorption refrigeration for cooling, along with Organic Rankine Cycle and photovoltaic systems for electricity generation. System modeling and simulation have been implemented in Dymola environment with the use of Modelica equation-based modeling language. The accuracy of the model response has been validated against available measurements. Specific design and control measures have been proposed, simulated in a transient fashion and evaluated in terms of (i) RES generation, (ii) solar fraction and (iii) temporal flexibility. The measures examined, including the placement of a Li-ion battery, resulted in an increase of 24.6% in the heating demand solar contribution and of 7.9% in the renewable energy generated for the electricity demand, over the examined periods. [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]

Purpose: Mining of raw materials have both positive (e.g., creation of values and jobs along their supply chains and the supply chains they enter) and negative social impacts (e.g., affecting safe and healthy living conditions of the local community or through the risk of corruption). A new mining paradigm, small-scale "switch-on switch-off" (SOSO) mining, is based on the design of a flexible and modular mining plant (MMP) and aims at exploiting quickly and safely European small high grade deposits of raw materials, including critical. The goal of this study is to assess the social implications of this new mining paradigm on the value chain of the MMP. Methods: A social hotspot assessment is conducted on pilot-scale operations of an MMP led in Bosnia and Herzegovina for the production of lead concentrate. The assessment is conducted using the performance reference point method. The background system is modeled through the PSILCA v2.0 database, while the foreground system is modeled using on-site data completed with PSILCA information. Results: The assessment reveals six main hotspots induced by both the foreground and the background systems and occurring mainly in Bosnia and Herzegovina. These hotspots can be divided into three groups: (1) local preoccupations within the community: "contribution to environmental load" and "public sector corruption," (2) measures that can be put in place by the MMP operator: "social responsibility along the supply chain" and "certified environmental management," and (3) the conditions prevailing in the country: "sanitation coverage" and "workers affected by natural disasters." Two sensitivity assessments are conducted in order to test the operating conditions of the MMP: switching from a diesel generator to a renewable source of energy supply and switching the country of operation to Greece, host of a similar deposit that could be potentially exploited thanks to the MMP. Switching the electricity supply system increases the overall risk due to the increase in potential impacts occurring on the renewable energy supply chain (e.g., battery manufacturing). When switching the country of operation to Greece, the overall potential impacts are predicted to decrease. Conclusions: This study performed on pilot-scale operations provides information on potential social and socio-economic impacts and recommendations to limit these impacts in case of widespread use of the SOSO approach. In a broader perspective, having better knowledge of social implications linked to the mining and metals sector will help better understanding their implications in the various value chains they enter. [ABSTRACT FROM AUTHOR]

Global economic growth is accompanied by increased energy demand, thus conventional fuels such as coal, oil and gas, which are the primary energy sources, are gradually being depleted. At the same time, the combustion of conventional fuel for energy production causes serious adverse effects on the environment and contributes to climate change due to the emitted greenhouse gases. For the above reasons, most of the developed and developing countries especially during the last decades, have introduced various incentives for the greater penetration of renewable energy sources (RES) in all sectors of the economy. Concerning the building sector, several measures have been adopted, including the promotion of energy efficiency and energy saving. A significant proportion of the building stock are the school buildings where students and teachers spend a significant proportion of their daily time. Teachers' attitudes and views, especially the school unit managers concerning the use of RES in schools, are important in the effort to rationalize and control energy use. This study was conducted through a structured questionnaire applied to a sample of 510 school managers in Greece's primary and secondary education. The school unit managerial role for the case of Greek schools is performed by the school principal who has both administrative and educational duties. Statistical analysis included the application of Friedman's test and hypothesis test on questions concerning school manager environmental perceptions and energy-saving habits. According to the results, Greek school managers have a high degree of environmental sensitivity, since 97.6 % agreed or strongly agreed that the main concern should focus on energy saving. Furthermore, 71% of the respondent reported to have good knowledge on solar energy, followed by 64% on wind energy while only 34% are knowledgeable on biomass. Almost all the respondents (99%) agreed that it is important to provide more RES-orientated education through the taught curricula. Concerning energy saving behaviour, around 90% reported that they switch off the lights when leaving the classroom and they close the windows when the air-condition is operating. Hypothesis tests revealed a relationship between the school managers' ecological beliefs, the energy saving habits in the school environment, and the recognition of the importance of environmental education. Conclusions highlighted the need to intensify environmental education programs in the school environment concerning RES in schools. This will lead to a higher level of environmental awareness of both teachers and students and therefore to a more dynamic behaviour towards the effort to “greenify” the school environment. [ABSTRACT FROM AUTHOR]

Purpose: Fish is a delicate and valuable source of protein, and aquaculture is expected to provide the required amount of fish needed at reasonable prices. Packaging is a vital stage to preserve hygiene, quality and freshness of aquaculture products. The purpose of this study was to identify environmental hotspots in farmed seabass and meagre during the packaging stage and to examine scenarios for reducing environmental impacts, aiming at greenhouse gas neutrality. Methods: The life cycle assessment method was applied for the first time at three packaging plants of farmed seabass and meagre in western Greece, in order to assess their environmental impacts, taking into account the amount of electricity, expanded polystyrene, and other plastic and packaging materials needed. Moreover, different scenarios were designed involving the energy mix/alternative sources, recycling and reuse of packaging materials, and the replacement of standard polystyrene boxes and wooden pallets, in order to suggest environmentally friendly improvements in the packaging process. Results and discussion: Conventional operation of seabass and meagre packaging plants requires significant amounts of energy and packaging materials. In fact, electricity, boxes and pallets were documented as the main contributors to most of the environmental impact indicators. Seabass packaging had a slightly lower overall environmental impact compared to meagre, due to its smaller market size. Impact minimization scenarios resulted in various degrees of reduction of environmental burdens in both species; however, near-zero GHG emissions were achieved when energy from photovoltaic panels and recycling/reuse of packaging materials were combined with the use of non-fossil-based boxes and recyclable pallets. Such readily applicable adjustments to the conventional operation of packaging plants would contribute to overall environmental sustainability and to better consumer acceptability of the final product. Conclusions: In a nutshell, the life cycle assessment method proved to be a valuable tool for assessing the environmental performance of Mediterranean aquaculture packaging processes. Moreover, it served to identify critical factors directly related to the EU GHG neutrality target. Accordingly, environmentally friendly decision-making/strategic management in the farmed fish packaging sector will inevitably rely on alternative energy sources, recycling of packaging materials, and use of recyclable corrugated board boxes or similar non-fossil-based materials. [ABSTRACT FROM AUTHOR]

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]

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]

• 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 scope of this study is to investigate the main determinants of renewable energy investments in Greece. For this reason, we build an appropriate framework to infer the decision‐making process in the renewable energy sources (RES). The main drivers are then categorized under two groups as economic, and behavioral ones. In the next stage, we rely on binomial (logit and probit) and quantile regression analysis to estimate the impact of these factors on investment decisions towards RES. Our findings indicate that investors who gain better access to knowledge and exhibit a more positive attitude towards the contribution of artificial intelligence (AI) on the RES industry have a higher share of renewables in their portfolio. We argue that these investors are willing to invest a higher amount in the RES industry today. At the same time, quantile regression models illustrate that this relationship is nonmonotonic (i.e., inverted U shaped curve), arguing that positive attitudes towards the contribution of behavioral factors on RES are not adequate to encourage investments after crossing a certain point (threshold). Based on the empirical findings, we argue that the message to policymakers and government officials is to promote a faster penetration of low carbon technologies to achieve sustainable economic and social growth. [ABSTRACT FROM AUTHOR]

This study empirically investigates the relationship between renewable and non-renewable energy consumption and economic growth in Greece, using annual data from 1990 to 2016. The results reveal that there is a significant positive long-run effect of both, renewable and non-renewable energy consumption, on economic growth. In the short run, the results are in the same direction. The overall findings imply that renewable and non-renewable energy consumption significantly stimulates economic growth in Greece. Taken into account that renewable energy sources reduce carbon emissions and protect the environment, the expansion of renewable energy consumption with a strategic plan is required. The challenge for policymakers in Greece is to substitute conventional energy fuels with others that produce less pollution and to raise renewable energy sources by keeping a sustainable and long-term growth path. Energy policy should be combined with the implementation of coherent, consistent and sequential renewable energy-enhancing structural reforms. [ABSTRACT FROM AUTHOR]

Total final energy consumption in Hellenic buildings reached 6.5 × 106 tons of oil equivalent (Mtoe) or 34.2% of the total (2010), of which 4.6 Mtoe in residential buildings. National implementation of the European Directive on the energy performance of buildings (EPBD) in Greece since 2010 is the first coordinated attempt to improve the energy performance of Hellenic buildings. In this framework, as of 2011, new buildings have an annual solar fraction of 60% for sanitary hot water production from solar thermal systems. Efforts are currently underway to comply with the EPBD recast so that by the end of the decade, all new buildings are nearly zero-energy buildings and that the very low amount of energy required should be covered to a very significant extent by energy from renewable energy sources (RESs). At the same time, the unprecedented financial crisis and escalating energy costs in Greece have reemphasized the need to explore the opportunities of renewables and energy conservation measures (ECMs). This paper reviews the relevant RES policies and status, with an emphasis to the Hellenic buildings. Using Hellenic typical residential buildings, the national requirements, and methodologies, this work quantifies the benefits of using solar thermal collectors to cover 100% of the domestic hot water demand. The results illustrate that, even as a single action, this popular ECM can improve the energy class of existing residential buildings and in some cases even reach an energy class-B, which is the minimum requirement for new buildings. Combining with other cost effective ECMs and exploiting RES for space heating and cooling can help building owners to not simply comply with new regulations but most important reduce the operational cost of buildings while maintaining a comfortable indoor thermal environment. [ABSTRACT FROM AUTHOR]

The latest measure for the development of photovoltaics in Greece utilizes the net-metering scheme. Under this scheme the energy produced by a PV system may be either consumed by the local loads or be injected to the grid. The final cost reported in an electricity bill depends upon the energy produced by the PV system, the energy absorbed from the grid and the energy injected to the grid. Consequently, the actual electricity consumption profile is important to estimate the benefit from the use of this renewable energy source. The state latest statistics in Greece for households reveal that the typical electrical consumption is 3750 kWh while 10244 kWh are consumed in the form of thermal energy. We adopt in our calculations the above amount of electrical energy but assume four different scenarios. These different hourly profiles are examined to study the effects of synchronization upon the final cost of energy. The above scenarios are applied to areas in different climate zones in Greece (Heraklion, Athens and Thessaloniki) to examine the dependence of the hourly profiles and the solar potential upon the financial data with respect to internal rate of return, payback times, net present value and the levelized cost of energy. These parameters are affected by the initial system cost and the financial parameters. [ABSTRACT FROM AUTHOR]

Desalination technology, and reverse osmosis in particular, is used by several island authorities in Greece to address water scarcity. However, this is a highly energy-intensive technique, requiring the consumption of significant quantities of fossil fuels. The case of Syros Island is presented, to demonstrate the strong water–energy link in the operation of desalination plants. The article also discusses the use of renewable energy sources as a means for reducing the energy intensity of desalination. [ABSTRACT FROM PUBLISHER]

Desalination technology, and reverse osmosis in particular, is used by several island authorities in Greece to address water scarcity. However, this is a highly energy-intensive technique, requiring the consumption of significant quantities of fossil fuels. The case of Syros Island is presented, to demonstrate the strong water–energy link in the operation of desalination plants. The article also discusses the use of renewable energy sources as a means for reducing the energy intensity of desalination. [ABSTRACT FROM AUTHOR]

The efficiency of fiscal support for electricity generation from renewable energy sources (RES-E) is a multifaceted notion that cannot be adequately described by a single metric. Efficiency is related to the ability of a policy measure to support deployment without creating negative feedback effects. These negative effects may stem from saturation of the grid's ability to absorb an increased amount of RES-E power, the inability of regulatory bodies to cope with the larger workload due to the increased number of projects requesting permits or from rent-seeking behavior. Furthermore, the primary rationale for feed-in tariffs (FITs) and other fiscal support schemes is that increased deployment of RES-E technologies will lead to reductions in costs and increases in efficiency. As a result, the efficiency of an RES-E support policy should be also judged by its ability to capitalize on cost reductions. Overall, we present an approach to facilitate ongoing assessments of the efficiency of support measures for RES-E deployment. We demonstrate the proposed approach using the FIT support policy in Greece as a case study. In particular, the RES-E support policy in Greece has been recently revised through tariff cuts and a moratorium on new production licenses. We aim to demonstrate that if publicly available data are appropriately monitored, a policy revision can take place in a timelier and less disruptive manner. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Royal Anthropological Institute is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The scope of the present work is the techno-economic study with concern for the environmental issues and the investigation of the viability of an offshore wind farm in the Greek sea area, northeast of the island of Limnos. In the context of this study, the wind data, the suitable location for the installation of the wind turbines beyond nature protected areas, the type of the wind turbines, the losses due to wind turbines interaction, and the visual impact at the respective study areas are analyzed. Moreover, reliable costing models are used and applied, internationally recognized for techno-economic studies of offshore wind farms. Thereafter, the viability of the project is studied through investment benchmarks. This means that specific economic indices are estimated indicating whether the realization of such an investment is viable or not. In conclusion, based on the analysis performed in this study, it is noted that in the Greek archipelago and especially at the island of Limnos, there is a sufficient offshore wind potential at low depths and at relatively short distances from the shore. These circumstances are necessary conditions for the development of offshore wind farms in these areas. Moreover, economic estimations based on current data of grants, taxation, interest rates, etc., showed that the investment is sustainable, having a cost of energy production equal to 87.92 €/MW h. [ABSTRACT FROM AUTHOR]

Climate and energy crises are increasing worldwide. Community-led humanitarian engineering interventions for localized sustainable development and disaster resilience could support populations at risk. This article presents findings from a study that investigated flood response and energy needs of two riparian communities in Greece and Nepal. The findings indicate that the co-development of a hybrid unit for hydropower generation and flood warning is most preferred. This prototype could find applications in different riparian areas as either a main or supplementary system. [ABSTRACT FROM AUTHOR]

The article explores a taxation framework for energy production from Renewable Energy Sources (RES) in Greece. It discusses how the framework may contravene the general principles of the European Union's policy on RES development. The promotion of renewable energy generation through a guaranteed feed-in tariff system in the country is noted. Also mentioned is the incompatibility of retroactive taxation measures in the EU.

The development of renewable energy plants (REPs) is mostly seen from the technical, economic, and legal perspectives, with the cultural and social aspects often not being taken into account, sometimes resulting in a serious impact on the progress of the investment. This is particularly evident with historic environments, where local communities tend to have a negative attitude towards the development of REPs, causing severe delays and even the cancellation of the investment. This article examines the impact of REPs on historic environments in relation to the attitude of local communities, using a variety of case studies from Greece. The aim is to develop a new approach of broader applicability that would link the development of REPs to the protection of historic environments and the sustainable development of local communities, and then provide specific recommendations (consisting of practical steps) for the implementation of this approach to how a renewable energy project can succeed while at the same time respecting the historic environment and engaging the local community. [ABSTRACT FROM AUTHOR]

Copyright of Hydrological Sciences Journal/Journal des Sciences Hydrologiques is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Renewable energy sources (RES), excluding large hydroelectric plants, currently produce 4.21% of total electricity production in Greece. Even when considering the additional production from large hydroelectric plants, which accounts for some 7.8%, the distance to be covered towards the objective of 20% electricity produced from RES by 2010 and respectively towards 20% of total energy production by 2020 is discouraging. The potential, however, does exist; unfortunately so do serious barriers. On the other hand, solid waste management (SWM) is an issue that generates continuously increasing interest due to the extra amounts of solid waste generated; the lack of existing disposal facilities with adequate infrastructure and integrated management plans, also often accompanied by legislative and institutional gaps. However, socio-economic and public awareness problems are still met in the planning and implementation of RES and SWM projects, together with the lack of a complete national cadastre and a spatial development master plan, specifying areas eligible for RES and SWM development. Specific barriers occur for individual RES and the on-going inclusion of waste-derived renewable energy in the examined palette further increases the complexity of the entire issue. The consolidated study of this broad set of barriers was a main task of the present study which was carried out within the frame of a Hellenic—Canadian research project; the main results will be discussed herein. [ABSTRACT FROM AUTHOR]

This article studies the dependence of the daily total solar radiation during a given day on the daily total solar radiation of the previous day, for a location in southwestern Greece. Fourteen years dataset of daily total solar radiation is used. This data is classified in two subsets, namely, one of “good” and a second of “bad” weather. The conditional probabilities of the daily clearness index “good-to-good” weather, P11, and “bad-to-good” weather, P01, are calculated. A satisfactory fitting of the obtained probabilities to parametric mathematical equations, is proposed. For solar energy applications, the first-order two-state Markov model is described by a Bernoulli random variable. Therefore, a sequence of “good” or “bad” weather of k consecutive days has been estimated by applying the equations of the Bernoulli distribution. The results of this work can be used in several solar energy system calculations, such as for weather data generation in solar simulation processes. [ABSTRACT FROM AUTHOR]

Energy usage, in the Greek transport sector, takes the form of gasoline consumption by automobiles, diesel oil for taxis, trucks, maritime transport, and railroads as well as jet fuel for aircraft. The control of CO2 emissions constitutes a major environmental issue in most countries and many authorities seek to stabilize or decrease these emissions. During the past decade, biofuels in the form of blended gasoline and biodiesel have begun to find places in the energy economy since a sustainable transport future requires the reduction of CO2 emissions. The Greek car market shows a remarkably low rate in the penetration of biodiesel compared to the average European Union market. In this study we try to find out the combined effects of probable changes in biodiesel and gasoline future fuel consumption in the city of Athens. [ABSTRACT FROM AUTHOR]

In autonomous islands, the wind penetration is restricted due to technical reasons related with the safe operation of the electrical systems. The combined use of wind power with pumped storage (WPS) systems is considered as a means to exploit the abundant wind potential, increase the wind installed capacity and substitute conventional peak supply. An approach for the simulation of the autonomous electrical systems is proposed and applied in three islands. The simulation is based on the non-dynamic analysis of the electrical system, in order to calculate the energy contribution of the different power units. The aim is to analyse the prospects of WPS systems to decrease the electrical system's cost. The results show that the integration of WPS in autonomous islands may decrease the system's electricity production cost. [ABSTRACT FROM AUTHOR]

The European policy target of substantially increasing the share of renewable energy in electricity generation, in combination with national subsidization support schemes, has strongly motivated private investors towards this business sector. In Greece, this interest is particularly apparent in the case of wind energy exploitation, due to a favourable legislative framework and the important wind potential available in several Greek regions. In such endowed regions, a very high number of applications were submitted to the competent authority, most of which compete for the same most attractive (windy) sites. The selection among these applications is a multicriteria problem that has been solved with the support of a Decision-Aid tool combining the multicriteria classification method ELECTRE-TRI with Integer Linear Programming. The developed approach takes into account both, the performances of the applications to the evaluation criteria, as well as a number of technical and policy constraints. [ABSTRACT FROM AUTHOR]

This study investigated factors that might influence teachers' intention to choose Renewable Energy Sources as an optional module. The research involved 454 Greek teachers working in the archipelagos of the southern Aegean region in Greece, an area with significant potential for the development of Renewable Energy Sources (RES). This potential however remains largely unexploited partly due to local community reluctance towards RES development in the area. Although renewable energy education is considered to be necessary for further RES development, RES are not among teachers' first choice as an environmental module. We found that, despite teachers demonstrating highly positive attitudes towards RES, they consider local communities to be rather non-supportive of local RES development. A relationship between teachers' moderate intention to teach RES and teachers' perceptions of locals as non-supportive towards RES was found. We also found that local teachers feel more competent to teach about RES than non-local teachers. The latter are more motivated to comply with social pressure than locals. These findings emphasize the need for renewable energy education policy makers to take into account local communities' role in influencing the teaching of RES and to provide teachers with the appropriate skills in order to competently handle potential oppositions. [ABSTRACT FROM AUTHOR]

Hybrid Renewable Energy Systems (HRES) are an attractive solution for the supply of electricity in remote areas like islands and communities where grid extension is difficult. Hybrid systems combine renewable energy sources with conventional units and battery storage in order to provide energy in an off-grid or on-grid system. The purpose of this study is to examine the techno-economical feasibility and viability of a hybrid system in Donoussa island, Greece, in different scenarios. A techno-economic analysis was conducted for a hybrid renewable energy system in three scenarios with different percentages of adoption rate (20%, 50% and 100%)and with different system configurations. Using HOMER Pro software the optimal system configuration between the feasible configurations of each scenario was selected, based on lowest Net Present Cost (NPC), minimum Excess Electricity percentage, and Levelized Cost of Energy (LCoE). The results obtained by the simulation could offer some operational references for a practical hybrid system in Donoussa island. The simulation results confirm the application of a hybrid system with 0% of Excess Electricity, reasonable NPC and LCoE and a decent amount of renewable integration. [ABSTRACT FROM AUTHOR]

There has been intense debate over the depletion of fossil fuel reserves in recent decades as well as the greenhouse gas emissions that are causing climate change. At the same time, new legislation in Greece, national policies, European policies, and realistic needs, need effective waste management and the protection of national resources. As a result, it seems a necessity to exploit waste treatments, while expanding the use of renewable energy sources. In this study, an attempt is made to focus our interest and research on a specific biomass waste stream, namely the waste biomass from the agricultural-livestock sector. The possibility of processing these wastes through the technology of biomass biorefinery with anaerobic digestion as its central process will be studied. The technology of anaerobic digestion is a process widely used for the treatment of agricultural residues and livestock waste as well as for the exploitation of energy crops (energy development, soil enhancement) mainly in countries in Europe and globally. This study reviews the biorefinery biomass technology, the energy production technology, production of biofuels, and new materials from waste biomass at the behest of the circular economy and bioeconomy. Additionally, this research will be an introduction in maximizing the potential of the full utilization of agricultural and livestock waste, and the by-products that can be produced from these processes. [ABSTRACT FROM AUTHOR]

Weather variables are an important driver of power generation from renewable energy sources. However, accurately predicting such variables is a challenging task, which has a significant impact on the accuracy of the power generation forecasts. In this study, we explore the impact of imperfect weather forecasts on two classes of forecasting methods (statistical and machine learning) for the case of wind power generation. We perform a stress test analysis to measure the robustness of different methods on the imperfect weather input, focusing on both the point forecasts and the 95% prediction intervals. The results indicate that different methods should be considered according to the uncertainty characterizing the weather forecasts. [ABSTRACT FROM AUTHOR]