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The building stock in southern Europe grossly lacks sufficient thermal envelope insulation, leading to high energy inputs and corresponding CO2 emissions. Phase change materials (PCMs) and vacuum insulations panels (VIPs) could be an innovative way to curtail the high heating and cooling energy inputs to maintain comfort; however, their efficiency and environmental performance in the southern Mediterranean climate is largely unknown. To this end, two demo houses, 27 m3 each, were constructed in the island of Crete, southern Greece. The first was constructed using conventional building materials, while in the second PCMs and VIPs were used, as a research test-bed. Actual life cycle inventory (LCI) data were collected and the life cycle assessment (LCA) methodology was employed to estimate the environmental impacts attributed both to their construction and operational phase. Compared to the conventional demo house the one covered with PCMs and VIPs appear to have a 34% higher total environmental footprint, which is attributed to the production process of PCMs and VIPs. Nonetheless, the energy savings observed during the operational phase, attributed to their higher thermal insulation, can compensate the higher environmental footprint of the construction phase within a year, depending on PCM's enthalpy. Specifically, it was identified that PCMs and VIPs largely reduced daily indoor temperature fluctuations, improving indoor thermal comfort and leading to energy savings. As such, even though their installation is associated with an initial higher environmental footprint, large energy savings, compared to conventional demo house, are achieved during its operational phase. This suggests that the introduction of PCMs and VIPs could be an efficient and environmentally friendly route to enhance energy savings and reduce the environmental footprint of building stock. © 2019 AIMS Press.

Summarization: Pyrolysis of high acidity olive oil, olive husk oil and animal fat was carried out under different atmospheres (vacuum, N2 and CH4), at constant temperature and different residence times. Bio-oils were the main pyrolysis products, with mass yields from 55.2% to 88.9%. The use of nitrogen or methane atmospheres led to an increase in the formation of gas products (14.1% to 26%), while increasing the residence time resulted in higher yields of gases and solids. The pyrolysis bio-oils contained 54.4% to 88.7% (w/w) of distillable liquids, collected as a light fraction and a heavy fraction. Both fractions were analysed by GC-MS to determine the hydrocarbon profiles and identification of functional groups. Vacuum pyrolysis promoted the formation of low molecular weight liquids while the use of a methane atmosphere increased the relative concentration of aliphatic components in the bio-oil. Παρουσιάστηκε στο: 4th International Conference Wastes: Solutions, Treatments and Opportunities

The energy potential of household used cooking oil (UCO) is practically unlimited. Its disposal, in some cases illegally, increases the cost and the energy consumption of domestic wastewater treatment, as well as the GHG emissions associated with its biodegradation (non-CO2 emissions). Moreover it should be added the heavy environmental pollution load. The European initiative RecOil (Promotion of used cooking oil recycling for sustainable biodiesel production), co-funded by the Intelligent Energy Europe programme of the European Commission, aims to increase sustainable biodiesel production and its market intake by enhancing the household used cooking oil (UCO) collection and transformation at local and regional level. RecOil will assess the “UCO to biodiesel” chain best practices, through a household survey, acknowledging the industry expertise, and local/regional authorities’ cooperation, to develop an on-line decision-making guide in order to assist stakeholders in developing a chain adjusted to local specificities (geographic, social, economic, legislative, and ). Pilot projects will also be implemented, according to the most promising practices identified, for validation. The RecOil implementation will result in primary energy savings estimated in 1.300 toe/year and the reduction of GHG emissions 14.413 tCO2., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1510-1514

28th European Photovoltaic Solar Energy Conference and Exhibition; 4490-4496, In the past few years the PV sector has experienced a very rapid increase in terms of installed capacity. PV was the 1st source of electricity installed in Europe in 2011, with 21.6 GWp of new power generation capacity. As comparison to other technologies, during the same period of time there were only new capacity of 9.6 GW for wind power plants, 9.7 GW for gas power plants, 2.1 GW for coal power plants, 0.6 GW for large hydro power plants and a decommissioning of 1.1 GW of fuel oil power plants and 6,2 GW of nuclear power plants. Based on these figures, PV has been seen as a potential and feasible electricity source in Europe. In the upcoming years the installed capacity of PV has to further increase to reach the “20-20-20” binding targets of 20% of RES in energy consumption until 2020, which corresponds to 30-35% of the electricity demand from RES, according the Renewable Energy Directive (2009/28/EC) and beyond, until 2050, to achieve the targets of the Energy Roadmap 2050. According to the High RES scenario of the Energy Roadmap 2050, the share of RES in electricity should reach 75% in gross final energy consumption and 97% in terms of electricity production. Among the other renewable power technologies, PV will provide a relevant contribution to reach these ambitious European targets. To achieve such contribution from RES electricity, several key challenges need to be further addressed. At the time being, the status quo in the field of electricity generation is still based on a centralized concept, where electricity producers from small-scale renewable energy systems, such as photovoltaic systems, are forced to adapt their needs, in terms of legal and regulatory framework, grid access and market design rules, to the infrastructures developed to support a centralized approach for electricity production. The PV parity project aims at defining an appropriate policy and legal framework to ensure a sustainable PV market growth. To reach this ambitious target, during the PV Parity project, European and National policy makers have been provided with objective and transparent recommendations to implement support schemes to ensure that PV will become competitive with other electricity sources in Europe and to go beyond the PV competitiveness, in order to ensure a sustainable PV market growth until 2020, 2050 and beyond.

27th European Photovoltaic Solar Energy Conference and Exhibition; 3602-3609, This study presents the performance analysis of two twin grid connected PV Systems, installed in two hellenic areas: the Agricultural University of Athens (37° 59' N, 23° 42' E) and the Technical University of Crete, Chania (35° 31' N, 24° 04' E). Both installations consist of tandem amorphous and microcrystalline silicon thin film (a- Si/μ-Si ) solar modules (SHARP NA-F121G5). The nominal power output of each system at STC is 2.178 W. The performance analysis is drawn on data that have been collected during a two (2) years period (June 2010-May 2012). The aim of this paper is to present the performance analysis of the previous mentioned PV twin installations. Additionally comparisons are made between their performances and between the performance of each of them in the first and the second year of operation under high-temperature subtropical Mediterranean area conditions. To evaluate the performance of each PV system some important normalized parameters such as yields, losses and efficiencies are computed. These parameters include the final yield (YF), the reference yield (YR), the array yield (YA), the performance ratio (PR) ,the PV array efficiency (nPV), the system efficiency (nsys), the inverter efficiency (ninv) . The Array capture losses (Lc) and System losses (Ls) were also calculated.

27th European Photovoltaic Solar Energy Conference and Exhibition; 305-310, It is well known that photovoltaic efficiency is strongly temperature dependent. As the temperature raises, the internal resistance of the material increases and the electrical conductivity decreases. This can be a major problem in building-integrated photovoltaic (PV) devices where free convection cooling is limited, especially during summer in hot climate such as in South Greece. Various existing techniques to lower PV panels’ temperature are initially presented in this paper. In this study focuses on the combination of a photovoltaic panel with a Phase Change Material (PCM) in order to reduce the daily temperature of the PV panel and improve the overall efficiency of the system. The experimental concept of integrating PCM on the PV panels located in the laboratory of Renewable and Sustainable Energy Systems, Technical University of Crete, Chania is presented. In Mediterranean climates there are very limited results of the behaviour of amorphous and microcrystalline silicon thin film solar cells modules when combined with PCMs.

27th European Photovoltaic Solar Energy Conference and Exhibition; 4379-4383, The European Directive 2009/28/EC for the promotion of Renewable Energy Sources (RES) sets the target of supplying 20% of EU’s final energy consumption from renewable energy sources by 2020, which corresponds to meeting 30-35% of the electricity demand from RES. High RES scenario presented in Energy Roadmap 2050 by the European Commission foresees that 75% of the gross final energy consumption and 97% of the electricity consumption can be supplied from RES by 2050. With the increasing system performances and decreasing production costs, PV will provide a strong contribution to reach these targets. The PV sector needs an appropriate policy and legal framework to ensure a sustainable market growth. To reach this ambitious target, European and National policy makers need to be provided with objective and transparent information on the potentiality of the PV sector, such as the competitiveness of electricity produced by PV systems, and on the appropriate support schemes to reach the PV competitiveness as well as to achieve further targets. Through the PV Parity project, policy makers will obtain the necessary information to ensure a sustainable policy framework for the PV sector. In order to ensure that the documentation elaborated during the PV Parity project is objective and transparent, the results achieved during the project will be shared with the relevant stakeholders of the PV sector, such as utilities, distributor system operators (DSOs), research institutes on energy and legislation, energy regulators. The steps to be carried out during the PV Parity project in order to reach a sustainable policy framework for the PV sector are the following: • definition of PV competitiveness • roadmaps to PV grid parity in 11 European Countries • definition of the relevance of PV electricity import from Middle East North Africa (MENA) countries • cost / benefits of the PV network integration • state of the art of the support schemes • elaboration of alternative support schemes • dissemination of the project outcomes to National and European policy makers The European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC) presents a unique opportunity to share information on the initial results of the PV Parity project such as the definition of PV competitiveness and the roadmaps towards the PV competitiveness. The PV Parity project started in June 2011 and will end in November 2013. The PV Parity project is co-financed by the European Commission in the framework of the Intelligent Energy Europe (IEE) Program.

27th European Photovoltaic Solar Energy Conference and Exhibition; 4712-4716, The European Union’s energy strategy sets specific targets for a sustainable growth during the coming decades, including reaching a 20% share of renewables in final energy consumption till 2020. To achieve that, a number of initiatives and measures have been in force. The favorable European policies as well as the Member States’ supporting legislations have resulted to high market growth for photovoltaics (PVs). However, the PV technologies’ application requires highly qualified technicians for PV installation, repair and maintenance. As national markets have been growing faster than the qualified PV installers force can satisfy, the appropriate training systems and certification schemes need to be developed in order to validate the competence of the installers and to ensure efficient and good functioning of installed PV systems. This is the scope of the European initiative PVTRIN, supported by the Intelligent Energy Europe programme of the European Commission, which focuses on the development of an appropriate training and certification scheme for technicians active in the installation and maintenance of small scale PV systems and sets the base for a mutual acknowledged certification scheme within Member States.

26th European Photovoltaic Solar Energy Conference and Exhibition; 4684-4688, The European Energy and Climate Change policies, as well as the supporting EU Member States’ legislations have resulted in high market growth for photovoltaics. Applying PV technologies however, requires highly-qualified technicians to install, repair and maintain them. Until today, national markets have been growing faster than the qualified PV installers force can satisfy. The PVTRIN training and certification scheme, creating a qualified installer workforce, supports the European Photovoltaic industry in addressing the need for skilled technicians. It will, initially, be implemented in six (6) countries: Greece, Bulgaria, Croatia, Cyprus, Romania and Spain, incorporating the criteria set by the 2009/28/EC Directive for qualification schemes in each Member State, as well as the national legislation. The certified installers will gain professional competitive advantage, improving their technical skills and knowledge. Having more qualified PV installers should lead to fewer technical failures, more effective operation of PV systems, better maintenance procedures, and lower maintenance costs. The resulting increased confidence of PV investors should then lead to higher market growth. The increased PV technology penetration to the energy mix, will assist the EU countries in achieving the mandatory target of a 20% share of energy from RES, in overall EU energy consumption, by 2020.

Olive pomace oil and waste lard are two feedstocks with promising potential for sustainable biodiesel production in the island of Crete, Greece. Olive pomace is an abundant by-product of the olive oil production process, in the Mediterranean. On the other hand, pork fat is a common by-product from pork meat industry with low price and limited uses. In the present study, we are considering that a sustainable biodiesel production system for the island of Crete can be achieved, if domestic agro-industrial byproducts will be exploited as a potential bioenergy feedstock. The purpose of the study was to evaluate the production potential and to define the production process for the efficient transformations of those raw materials to biodiesel. The experimental procedure carried out on a 23 experimental design for the production process optimization following the concept of two step acid – base catalyst process under mild conditions and subsequent dry-wet washing method. The effect of each evaluated process parameter as well as critical process and feedstock dependant biofuel properties are assessed, indicating strengths and weaknesses of each raw material towards sustainable biodiesel production., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 2051-2056

26th European Photovoltaic Solar Energy Conference and Exhibition; 4590-4593, Over the past years, the PV market has experienced significant growth rates worldwide. Large-scale investments as well as market growth in general resulted in improved system performance and reduced operation costs; hence power production costs are decreasing continuously. Market growth is largely policy-driven and depends on the support through favourable legal frameworks and support programmes such as feed-in tariffs, at least until the supported technology reaches grid parity, i.e. becomes cost competitive with conventional power generation systems. Financial support schemes are generally aiming at reaching grid parity which allows for lowering and finally stopping the support. In order to achieve this goal in a cost-efficient way, it is necessary to understand how grid parity is defined, which support schemes are best suited to achieve grid parity and which support is appropriate and needed after reaching grid parity. This paper focuses on the first results towards the definition of the PV grid parity obtained during the first part of the PV Parity project. This paper provides the methodology applied for the definition of the electricity market segments, which represent the “competitors” of PV electricity at different levels of installed PV power, and electricity prices for different market segments and their disaggregated cost components in selected European countries. The PV Parity project started in June 2011 and will end in May 2014. The PV Parity project is co-financed by the European Commission in the framework of the Intelligent Energy Europe (IEE) Program.

Biomass utilization as an alternative to the fossil fuels is of high interest, especially when the resulting waste heat is also captured and exploited as useful thermal energy source, in CHP energy systems. The aim of this paper is to present the development of a Decision Support System for the assessment of Biomass Energy Systems implementing the existing biomass combustion technologies, including Biomass Gasification, Integrated Gas Turbine-Steam Generator, Co-Firing, and Biomass Direct Combustion models for the production of Power and Thermal energy. As example a district heating system utilizing the produced thermal energy is examined, taking into consideration the optimum design of the building structures of the urban settlement next to the area of the plant. The objective of this task is to compile the main design variables of the energy model as well as the environmental advantages, against other energy systems using fossil fuels and the financial viability of relevant investment., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 2250-2253

26th European Photovoltaic Solar Energy Conference and Exhibition; 3635-3639, The performance of PV modules is usually specified under standard test conditions (STC); however the performance of the modules under real field conditions differs from the expectations derived from the results under STC due to variety of continuously changing conditions. Therefore it is important to monitor the behavior of PV modules under real field conditions, so automated computer-controlled monitoring systems are used to measure the solar irradiance, module temperature and other meteorological parameters. Additionally it is very important for the market development of PV systems to get accurate data for their operation under high-temperature conditions. The output will provide safe estimations about improvements to be taken in order to create large scale installations in the Mediterranean countries in Northern Africa and Middle East. The aim of this paper is to present a general overview of the performance analysis of the 2.18 kWp PV system during their first phase of operation.

Wood biomass has been –traditionally­ an important source of energy for heating and cooking, in many island communities in Europe, especially for the mountainous and rural ones. This paper aims present the methodology developed in order to collect and analyze quantitative and qualitative data regarding the use of wood biomass in Cyprus including its origination, the potential, the benefits and the consequences from the uncontrolled use and overexploitation of wood biomass, as well as to evaluate the general policy, social and economic impacts. The planned actions involve the identification of the quantities and the origin of wood biomass consumed in the mountainous areas of Cyprus (more than 40) with the analysis of data collected through a structured questionnaire and a dedicated field research. Also, measurements of the variation of air quality (CO2, CO, NOX, PM2.5, PM10, TPM) will be carried out, between winter and summer months for both indoor and outdoor air quality in mountain households. Relevant measurements will be performed in houses that use energy efficient fireplaces in order to determine any changes/improvement in air quality. After the completion of this project concerning the utilization of wood biomass in the mountainous communities it is expected to reveal important results on social, economic and environmental level. This study is financed by the Cyprus Research Promotion Foundation., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 361-364

26th European Photovoltaic Solar Energy Conference and Exhibition; 3604-3607, The number of installed PV systems in the Southern European countries is constantly rising. Given the high solar potential of their climate more people want to invest in photovoltaics. The market available technologies are increasing and there is a high interest in thin film technologies which present a lower purchase cost. The lower thermal coefficient of some of these technologies leaves expectations of comparable power output with the higher efficiency crystalline silicon technologies in the high temperatures of Southern Europe. Four PV technologies are installed at the Agricultural University of Athens, a 3 kWp monocrystalline, a 2.99 kWp polycrystalline, a 3.6 kWp CIS thin film and a 2.178 kWp micro and amorphous silicon thin film. By comparing operational data of these arrays in cold, mild and hot weather it is obvious that the micro and amorphous silicon thin film array produces more power during the hot summer weather and as a whole it can produce more energy throughout the year than the rest of the technologies.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 5314-5317, The high photovoltaic market growth rates, which are further favored by the EU supporting policies and the favorable national regulatory frameworks within the Member State countries, may turn to a threat for the PV industry due to the lack of adequately skilled workforce for the PV installation and maintenance. This may result in poorly installed systems with negative impact on the PV industry’s credibility and development. Furthermore, the interested parties (developers, designers, potential users) will eventually seek for acknowledged standards, skills certification and quality assurance throughout the development of a PV/BIPV application (design, installation, and maintenance). The PVTRIN, an Intelligent Energy Europe (IEE) project, addresses to these issues, by developing a training and certification scheme for the technicians/electricians/engineers that activate in the installation and maintenance of small scale PV systems. The training and certification scheme will incorporate the criteria set by the 2009/28/EC Directive, providing a supporting instrument for EU Member States to meet their obligations for acknowledged certifications for RES installers till 31/12/2012. Creating a qualified PV installers workforce, the increased confidence of potential PV owners will lead to market growth.

23rd European Photovoltaic Solar Energy Conference and Exhibition, 1-5 September 2008, Valencia, Spain; 3488-3491, The building under consideration is located in the island of Crete, Greece with almost the highest solarity in Europe. Its current use is the administration and several laboratories of the Environmental Engineering department in the campus of Technical University of Crete. The building has a large sun lounge, and the purpose of our study is to check the effect of its orientation in the energy production from Building Integrated Photovoltaic (BIPV) to be installed on it. By using the architectural and electromechanical data provided by the technical department of the university and the software tool ecotect v5.5 a 3D model has been developed and it has estimated the lighting level inside with or without the installed BIPV. By calculating the energy produced per BIPV surface we can suggest the optimum orientation of the building in order to maximize the electricity generated. Finally with the visualization routine the visual impact on the building after the PV installation can be estimated.

29th European Photovoltaic Solar Energy Conference and Exhibition; 2094-2097, The aim of this work is to present a dedicated Solar Polygeneration System (PROTEAS System) for the simultaneous production of electricity, hot water and air-conditioning. The core of the PROTEAS System is the innovative setup of Total Internal Reflection Reflectors made of plastic (Primary Optical System), which concentrate the solar rays up to 5,000 suns, homogenized to 1,000 suns by specially designed Total Internal Reflection Homogenizers (Secondary Optical System). High-efficiency Photovoltaic Cells are used to generate electricity. Furthermore, water -used for cooling down the photovoltaic cells- is heated up to 85-90°C and with the use of an advanced Absorption NH3 Heat Pump, is turned to chilled water for air-conditioning (7-12°C) and subsequently to domestic warm water about 45-55°C. PROTEAS modules are suitably spaced on a low-profile metallic ring which tracks the sun. The engineering of the system has already been initiated and some of the subsystems have been successfully developed. PROTEAS will be installed and evaluated in a building under real operational conditions in order to demonstrate the feasibility of the investment in terms of energy savings and assess its potential as a new market solution, which can be both cost effective and environmentally friendly.