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A comprehensive statistical analysis of energy poverty indicators is undertaken in the present paper, in an attempt to further understand the roots and results of the problem in Greece. Specifically, time-series data sets were analysed using various objective indicators, i.e. 10%, 2M, 2M EXP, M/2, M/2 EXP, as well as subjective indicators. Chi-square tests of Independence were performed and binary logistic regression models were developed to predict energy poverty (indicators of 10%, 2M and M/2), based on critical socio-economic factors. The logit model based on the 10% indicator presented the highest performance, reaching 32%. According to this model, the types of households mostly exposed to energy poverty were single families with dependent children and households located in Macedonia, increasing the relative probability of energy poverty by 7.0 and 6.5 times per unit, respectively. The outcomes derived can help policy-makers towards designing more targeted policies for tackling energy poverty in Greece. [ABSTRACT FROM AUTHOR]

The paper studied the phenomenon of energy poverty in the Municipality of Agrafa, a mountainous region of Greece, aiming to enhance knowledge on the phenomenon within mountainous areas. For this purpose, a primary survey was undertaken, and various objective and subjective indicators were monitored. It was found that 62.4% of households in Agrafa are classified as energy poor according to the 10% index based on actual energy costs, while the percentage escalates to 91.3% based on required costs. Also, the compression of energy needs emerges as a significant side of the problem. The subjective indicators highlight supplementary behavioural aspects of the phenomenon. A set of statistical tests was applied, i.e. cluster analysis, Chi-square tests of independence and regression analysis, enriching the outcomes of the research. Finally, the directions of energy policy are evaluated, highlighting the need for targeted research and policy measures adapted to mountainous areas. [ABSTRACT FROM AUTHOR]

This paper presents the examination of the mediating role of attitudes in the assumed relationship between values and conservation behaviour. SEM analysis revealed casual relationships between transcendent values (universalism and benevolence) and environmental unconcern as well as between environmental unconcern and conservation behaviour. The interference of attitudes in the relationship between values and behaviour tripled the percentage of variance explained. It was concluded that consumers, who value equality among people, tolerance, harmony, justice among all humans (high universalism values) and try to help people (high benevolence values) are more likely to minimise unconcern regarding environmental issues. It is exactly this attitudinal position that guides them to conserve water and energy in their households more frequently than their counterparts do. [ABSTRACT FROM AUTHOR]

This paper presents results of a study of the impact of future climate change scenarios as developed by the Intergovernmental Panel on Climate Change and implemented in weather files for specific future time slices (2020, 2050 and 2080) for the three climatic regions of Greece on the design of the external envelope of a hotel building in Greece. The impact of climate change on the hotel is assessed via hourly simulations of a calibrated model developed using the software TRNSYS. Additionally, the paper aims to identify optimal refurbishment strategies, given the constraints of the existing case-study building when transposed to the three different climatic zones in Greece. Two modes of the hotel building were studied: ‘all year’ and ‘seasonally’ operated. It was found that different external envelope energy-efficient strategies can be applied depending on the climatic zone and whether the hotel is all-year or seasonally operated. [ABSTRACT FROM AUTHOR]

The industry sector in Greece is responsible for one-quarter of the overall total final energy consumption accounting for 3.8 Mtoe in 2015. Since 2007, a 29% decrease is noted due to the financial crisis. The goal of this paper is to provide information on the current industrial energy profile of Greece, with particular reference to the steam industry. It presents the outcomes of 10 energy audits in industries that use steam followed by a list of possible measures: insulation, installation of a deaerator unit, heat recovery, automatic blowdown system and regulation of excessive air. The proposed measures result in energy savings of 5.8 GWh/year and show that the potential of energy savings in the Greek steam industry is quite considerable. [ABSTRACT FROM AUTHOR]

The aim of this paper is to explore the contribution of ecolabel HVAC systems, which are already available in the market, to the energy upgrade of existing dwellings, placing emphasis on whether they can constitute an efficient means of dealing with energy poverty. For this reason, the effects of these systems, when placed on an existing detached dwelling, are considered not only in relationship to energy savings, but also with other energy, environmental, social and economic criteria. Comparison is made between scenarios of the energy upgrade with various ecolabel HVAC systems, as well as scenarios of the energy upgrade of the building envelope. A parametric analysis is carried out, regarding the aforementioned criteria in the four climatic zones of Greece and three building typologies. Scenarios are prioritised, using the Multi-Attribute Utility Theory. Based on this analysis, conclusions are drawn, concerning the most advantageous energy saving actions, from an energy, environmental, social and economic point of view, for each building type and climatic zone. It is found that certain synergies of ecolabel HVAC systems with RES systems can be effective energy saving solutions, capable to face energy poverty. [ABSTRACT FROM AUTHOR]

The article focuses on environmental quality in the built environment, which was discussed during the Second International Conference on Passive and Low Energy Cooling for the Built Environment and the 28th AIVC Conference held in Crete, Greece. The theme of the events was "Building Low Energy Cooling and Advanced Ventilation Technologies in the 21st Century." There were almost 350 papers presented during the events.

In this paper we provide an assessment of the water–energy nexus for Greece. More specifically, the amount of freshwater consumed per unit of energy produced is determined: for both conventional (lignite, diesel and fuel oil-fired) and advanced (combined operation of gas turbine) thermal power plants in the electricity generation sector; for extraction and refining activities in the primary energy production sector; and for the production of biodiesel that is used as a blend in the ultimately delivered automotive diesel fuel. In addition, the amount of electricity consumed for the purposes of water supply and sewerage is presented. In view of the expected effects of climate change in the Mediterranean region, the results of this study highlight the need for authorities to prepare a national strategy that will ensure climate resilience in both energy and water sectors of the country. [ABSTRACT FROM AUTHOR]

Over the last years, the thermal comfort level during the summer period has been significantly increased due to the use of conventional cooling and air-conditioning systems, leading to higher electricity consumption. Solar cooling systems may provide the solution and become the leading technology in the future. The aim of this paper is to present a small-scale solar thermal system for cooling an office building in Athens, Greece. The study documents the system design, the monitoring procedure and equipment, and presents the experimental results from the first complete summer period. The daily electrical coefficient of performance (COP) of the absorption chiller of 48.6 and the electrical COP of the solar system 10.9 indicate the potential of solar cooling in small-scale systems. [ABSTRACT FROM AUTHOR]

The ongoing economic recession that hit Greece in 2009 has considerably influenced the use of domestic heating sources, as households struggle to reduce energy consumption and the respective costs. With global energy demand and the heating oil prices being rather volatile, but not in extremis during the last five years, alternative heating systems with the respective resources are being considered by consumers, in order to cut down heating expenses. At the same time, these alternatives are not always the greener or the most sustainable ones. The current paper presents and analyses the impacts of the recession on the consumers’ behaviour regarding space heating. A field survey was carried out, by means of interviews with questionnaires, in Northern Greece, an area where there is an increased energy demand for heating and hence an intensive need for efficient solutions. The questionnaire was structured in an appropriate way in order to collect the available data, not only to identify the significant variables but also to capture any minor details that could be helpful in achieving our goal: gain reliable information about the energy consumption and the respective cost of heating at an annual base as well as their interconnection. The variables employed in the survey include among others: the building type, construction year, surface, main heating system, alternative heating systems (fireplace, AC unit, electric heater and stove), operating hours, saving measures, energy consumption and annual income. Any potential correlation between the aforementioned parameters will be explored while a mathematical description of their relation will be further attempted. The results of the survey carried out during 2011 and 2012 are presented and the most noteworthy conclusions are highlighted. The initial outcome proves that there is a certain trend of shrinkage of the households’ budget spent for domestic heating purposes as a consequence of the inhabitants’ income reduction and the dramatic tax increase on energy. [ABSTRACT FROM AUTHOR]

Combined solar heating is an emerging technology that offers the potential for realising more efficient use of solar thermal energy in order to cover space heating and domestic hot-water loads. This paper is focused on small-scale applications of single-family residential dwellings in Greece. A system-level model was developed and validated. The model was exercised to evaluate strategies for optimal design and operation of solar combisystems (SCSs), using a range of performance criteria as objective functions for optimisation. The effect of SCS design and operating variables on steady-state system performance has been investigated. System design and operation optimisation has been performed through the integration and synthesis of system-level modelling with system optimal design, optimisation, and annual simulation studies to provide a comprehensive assessment. [ABSTRACT FROM PUBLISHER]

Greece by virtue of its coastal and especially its insular character holds a leading position in Europe with regard to domestic passenger shipping. Consequently, the high exhaust emissions of the fleet engaged in this activity have to be controlled in a sustainable manner for this sector and the society in general. In an attempt to promote the research towards the control of air pollutants and greenhouse gases in Greece, this paper examines the use of natural gas as a ‘cleaner’ fuel alternative to heavy and light fuel oils for domestic passenger shipping, focusing on its impact on air quality and climate change expressed through the external (damage) cost comparison between the two types of fuel. Furthermore, it highlights other critical parameters (e.g. private costs, bunkering and safety issues) which are bound to influence the fuel change from oil to natural gas in this sector of shipping. [ABSTRACT FROM AUTHOR]

The aim of this paper is to compare the asset and operational rating of buildings by the creation of a thermal model in TRNSYS 16 in order to simulate the thermal behaviour of a multi-storey (seven floors) office building that belongs to BYTE Computer S.A. located in Athens, Greece. Then based on the validated building model, the generalisation of this method is investigated for the creation of a virtual database for office building energy benchmarking in Greece. The data collected for the case-study building are based on engineering plans and studies, on in-situ measurements and mainly on the building management system (BMS) already implemented in the building. The building is modelled in detail by splitting it into 45 thermal zones. The simulation results are compared with the measured values provided by the BMS for two periods (winter and summer). The processing of the results leads to conclusions regarding the reliability of the model, the accuracy of asset rating compared to operational rating, as well as its usefulness in evaluating building retrofitting scenarios and its application as a general energy audit model for office buildings in Greece. [ABSTRACT FROM AUTHOR]

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]

During the last decades, the sustainable redesign of existing buildings has been gaining importance in both architectural practice and education. While based on the knowledge of the basic principles of bioclimatic design, it also requires a quantitative evaluation of the buildings' energy performance. This article aims at presenting the set-up, methodology and results of an undergraduate architectural technology course, which attempts to educate students on assessing the thermal characteristics and bioclimatic performance of existing buildings, proposing low-tech and low-cost interventions, and quantitatively evaluating their effect using energy simulation software. The applied strategies include thermal insulation, shading combined with natural ventilation for the summer period and their effect on the improvement of diurnal, inter-seasonal and annual thermal performance is evaluated. The results involve the assessment of the course set-up, the evolution during the five-year period that it has been taught, the teaching outcome, as well as the future progress and possible alterations. [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]

This work classifies and describes the main fields of solar energy exploitation in buildings in Greece, a country with high solar energy capacities. The study focuses on systems and technologies that apply to residential and commercial buildings following the prevailing design and construction practices (conventional buildings) and investigates the effects of the architectural and constructional characteristics of these buildings on the respective applications. In addition, it examines relevant applications in other building categories and in buildings with increased ecological sensitivity in their design and construction (green buildings). Through its findings, the study seeks to improve the efficiency and broaden the scope of solar energy applications in buildings in Greece to the benefit of their energy and environmental performance. [ABSTRACT FROM AUTHOR]

High-spatial resolution multispectral satellite images collected over the metropolitan Athens area in Greece were used to generate (a) a shortwave albedo map depicting the albedo spatial variations across the metropolitan area, (b) a fractional vegetation cover map showing the spatial distribution of urban vegetation and (c) a daytime and night-time land surface temperature (LST) map depicting the spatial variations of the surface temperature across the city. From LST maps, cooling and heating regions were identified and analysed to reveal relationships between surface heat islands and urban surface characteristics. Based on the data acquired with the use of satellite images and in order to better define the heat island problem and the mitigation measures that need to be taken, the most common building and paving materials used in the urban fabric of Athens were examined. Their optical properties were measured using a UV/VIS/NIR spectrophotometer fitted with an integrating sphere, an emissometer and their thermal performance was evaluated. Furthermore, measurements of the spectral reflectance help explore the possibility of increasing the near-infrared reflectance of materials in order to increase their total solar reflectance. The solar reflectance index of the samples was calculated in order to characterise them as 'cool' or 'warm'. Cool materials, with high albedo and thermal emittance values, attain lower surface temperatures when exposed to solar radiation, reducing the transference of heat to the environmental air. [ABSTRACT FROM AUTHOR]