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Abstract Chile has an immense renewable energy potential but their integration in the energy system constitutes a major challenge. The complex topography of the country, the isolation of the different electric grids and the variability of renewable energy sources, makes energy transmission from locations with high variable renewable power generation potential to the demand centres not an easy task. The present study aims at assessing the potential of combining solar power, wind power and storage systems to provide steady loads already from the source. Such a combination should take advantage of complementarity between variable renewable sources and serves to simplify their integration in the energy system. The analysis relies on an optimization model to size hybrid renewable energy systems and 10 years of weather data from the brand new ERA-5 reanalysis. Necessary system sizes to constantly generate 1 MWh of electricity for every hour during the period 2008-2017 are calculated for all possible locations across the country. The results show that the necessary generation and storage capacities to provide a steady energy output are very high even for areas with exceptionally high renewable energy potential. [ABSTRACT FROM AUTHOR]

Abstract This work evaluates potentials of photovoltaic and battery systems with additional micro-generation wind turbines (10.5 kW) to cover electricity demand of residential users in two countries in Central Europe. It relies on high-resolution regional reanalysis data and a techno-economical optimization model. Maps showing the number of wind turbines, photovoltaic and battery systems sizes necessary to supply electricity for clusters of electricity self-sufficient single-family houses across Germany and the Czech Republic are generated. No general trends that apply for the two countries concerning the relation between the sizes of the different technologies were identified. However, it was possible to determine several large areas where the inclusion of small wind turbines decreases the total system costs and considerably reduces the required storage capacities. Results are discussed and compared to previous work on self-sufficient single-family houses. [ABSTRACT FROM AUTHOR]

The Graciosa project combines a large scale battery energy storage system with renewable electricity generation from wind power and photovoltaics in a hybrid power plant to reduce the environmental impacts caused by the previous electricity generation by 100 % diesel combustion on Graciosa Island, Azores. The results of a Life Cycle Assessment show a reduction of environmental impacts of approx. 43 % due to the transformation to the hybrid electricity supply system with high shares of renewable energies (65 %). In the new electricity supply system, the majority of environmental impacts (> 60 %) is still caused by the remaining diesel based electricity generation. Environmental impacts, which are associated with the construction of the large scale battery energy storage system, account for only 6 % of total impacts. Wind power and photovoltaics account for 18 % and 14 %, respectively. [ABSTRACT FROM AUTHOR]

Reducing the energy demand of buildings has become one of the key points of the European Union. The issue related to the air conditioning of old and historical buildings is nowadays one of the most important field of operation for the primary energy saving and, at the same time, for the reduction of the CO 2 emission. The recent development of heat pump able to rise the supply of high temperature at the condenser side makes this technology suitable for the application also in historical buildings that are characterized by low thermal insulation and high thermal capacitance. In this context, the ground source heat pump systems can be used for both heating and cooling. The aim of this work is to analyze the thermal behavior of two historical buildings located in Italy, in Venice and Florence respectively. Detailed computer simulations of the buildings have been carried out by means of a transient calculation tool TRNSYS. Energy simulations of GSHP systems have been performed and a comparison with a common plant system using a gas boiler for heating and air-to-water chiller for cooling has been carried out. [ABSTRACT FROM AUTHOR]

This paper proposes an integrated rehabilitation project of an abandoned farmhouse in a rural area in Southern Italy. The building underwent a functional recovery to become a tourist accommodation. The use of natural materials can reduce energy consumption and carbon footprints considering environmental sustainability aspects. A proper selection of interventions targeted for the specific warm climate has led to benefits for heating, cooling and lighting in the interior spaces. The project also includes the integration of hydraulic facilities and landscaping, such as planting hedges, green barriers and native trees. [ABSTRACT FROM AUTHOR]

In GREENFOODS existing funding programs were mapped and evaluated concerning their acceptance and suitability in the food and beverage industry. The analysis have shown that most funding instruments were considered not easily available due, on the one hand, to limited budgets for the programs, and/or limits for eligible cost of individual measures and, on the other hand, to the complex and demanding application procedures. Based on this, recommendations were made for future development of programs. A follow-up is the H2020 project TrustEE focusing on innovative financing schemes (e.g. market oriented funds) for EE and RE implementations. [ABSTRACT FROM AUTHOR]

The district “Suurstoffi” in Central Switzerland is a progressive and innovative project in the field of low-temperature heating and cooling networks for which the main goal is to ensure a fully renewable energy supply and CO 2 -neutral operation. In order to verify the project goals, the Lucerne University for Applied Sciences has been monitoring and optimizing the district over the last five years. The monthly analysis of more than 300 measuring points and complementary user surveys resulted in numerous findings, the most relevant observation being the performance gap identified for the heat demand and electricity consumption of the heat pumps and auxiliary equipment. The survey of the network heat balance proved to be a relevant indicator to ensure the functioning of the project in the long-term. [ABSTRACT FROM AUTHOR]

Operators of public electricity grids today are faced with the challenge of integrating increasing numbers of renewable and decentralized energy sources such as wind turbines and photovoltaic power plants into their grids. These sources produce electricity in a very inconstant manner due to the volatility of wind and solar power which further complicates power grid control and management. One key component that is required for modern energy infrastructures is the capacity to store large amounts of energy in an economically feasible way. One solution that is being discussed in this context is “power-to-gas”, i.e. the use of surplus electricity to produce hydrogen (or even methane with an additional methanation process) which is then injected into the public natural gas grid. The huge storage capacity of the gas grid would serve as a buffer, offering benefits with regards to sustainability and climate protection while also being cost-effective since the required infrastructure is already in place. One consequence would be, however, that the distributed natural gas could contain larger and fluctuating amounts of hydrogen. There is some uncertainty how different gas-fired applications and processes react to these changes. While there have already been several investigations for domestic appliances (generally finding that moderate amounts of H 2 do not pose any safety risks, which is the primary focus of domestic gas utilization) there are still open questions concerning large-scale industrial gas utilization. Here, in addition to operational safety, factors like efficiency, pollutant emissions (NO X ), process stability and of course product quality have to be taken into account. In a German research project, Gas- und Wärme-Institut Essen e. V. (GWI) investigated the impact of higher and fluctuating hydrogen contents (up to 50 vol.-%, much higher than what is currently envisioned) on a variety of industrial combustion systems, using both numerical and experimental methods. The effects on operational aspects such as combustion behavior, flame monitoring and pollutant emissions were analyzed. Some results of these investigations will be presented in this contribution. [ABSTRACT FROM AUTHOR]

The study aims to assess the lived experience and the environmental heritage perceived level by residents of an high complexity rural area, and which is, in this context, the role played by production of renewable energies. The paper introduces the concept of rural capital as an effective tool for environmental heritage analysis and measurement. The proposed theoretical and methodological approach allows, in fact, its analysis in order to understand what dimensions related to territoriality are connected to the perceived level of environmental heritage at local level. Translated into operational terms, the methodology has resulted in an empirical analysis of a rural and inner area of Sicily, performed both through the examination of identified benchmark indicators, and through the observation of various phenomena, directly experienced by rural residents, detected by sample surveys that, by using a complex sampling design, allow more accurate estimates, modelled on the contexts. All these results are integrated by a multi-case study carried out by a qualitative survey detected both through desk analysis and in field observation, and through in-depth interviews with stakeholders and focus groups with local actors, all asked to assess in a participative way. The research proves that it is necessary to activate the processes of participation and social learning in order to energy planning of the territorial system, allowing at the same time to protect, preserve and enhance the environmental and natural heritage. [ABSTRACT FROM AUTHOR]

The sustainable energy transition of communities is one of the main targets within the European energy policies. Consistent energy planning is needed but conditioned by difficulties of city administrations to meet the necessary skills and have the necessary knowledge in order to lead the corresponding transition processes. The R4E project ( www.roadmapsforenergy.eu ) responds to the EE-07-2014 call entitled “Enhancing the capacity of public authorities to plan and implement sustainable energy policies and measures” within the Secure, Clean and Efficient Energy Work Programme of HORIZON 2020 of the European Commission R4E develops roadmapping capacities of 8 European partner cities (Eindhoven, Forlì, Istanbul, Newcastle, Murcia, Palermo, Sant Cugat and Tallinn) together with their local stakeholders, and provides them with the necessary knowledge about innovative energy solutions in the fields of smart buildings, smart mobility and smart urban spaces. A specific systemic approach to these future energy solutions has been developed, based on Deskstudies , Experts interviews and resulting Generic Roadmaps. The Deskstudies consist in Systemic Solution Maps, Technology Outlooks and Case Studies building a systemic knowledge generation tool for participants in multi-stakeholder processes. First applications and the feedback of stakeholders of city partners will be presented at the conference, discussing the usefulness of the approach for the city partners. The R4E project received funding from the European Union's Horizon 2020 research and innovation program under grant agreement Nº 649397. [ABSTRACT FROM AUTHOR]

This paper gives a comprehensive review about the recent advances related with the application of the nano fluid in the heat pipe solar collectors. Papers reviewed including theoretical, numerical and experimental up to date works related with the nanotechnology applications in this type of the solar collectors. A lot of literature are reviewed and summarized carefully in a useful table (Table 1) to give a wide overview about the role of the nano fluid in improving the heat pipe solar collectors. It was found that the use of the nano fluid in the heat pipe solar collectors can play a significant role in increasing the efficiency of these devises. [ABSTRACT FROM AUTHOR]

The work presented in this paper deals with the experimental tests which were carried out on a prototype of a rotary volumetric expansion device based on the Wankel mechanism. This expansion device is addressed to small size power plants (in the range 5-50 kW) for distributed micro-generation using various sources of thermal energy, such as sun, biomass and waste heat. The prototype was built using an internal combustion Wankel engine, employing the shaft, the rotor, the bearings, while the statoric case was newly built on the design of the University of Pisa. Firstly, the tests were carried out with the compressed air produced by a compressor, then the prototype was fed with the saturated steam produced by a biomass boiler. In the first case, the exhaust back-pressure was the atmospheric one, in the second case vacuum conditions were employed thanks to a condenser. The inlet pressure was between 4 and 8 bar. The results showed the capability of the prototype to rotate regularly at 3000 rpm, and allowed the validation of numerical models presented in previous papers. Moreover, the expansion device showed the capability of developing the expected power. [ABSTRACT FROM AUTHOR]

Moving Bed Heat Exchangers (MBHX) are a promising option to discharge thermal energy from hot bulk materials, which can be used in solar thermal power plants as heat transfer and storage medium. A precise determination of the flow field in a MBHX is required to predict its thermal performance. This paper presents a continuous model approach, based on the theory of soil mechanics to describe the granular flow inside the heat exchanger. The simulation results are compared to a preceding model and experimental data. For this purpose two different tube bundle geometries are analyzed. The results are evaluated by means of contour plots of the flow field and the velocity magnitude of the granular material at the tube surfaces. The new model captures the flow at the top of the tubes quite well but shows need for further improvement in the lower part of the tubes. [ABSTRACT FROM AUTHOR]

Italian coastal sites have the advantage of favorable climatic conditions to use mixed renewable energy sources, such as solar and wind. Harbors are safe places to install wind turbines where wind conditions are almost offshore. Space-borne remote sensing can provide information to determine solar and wind energy production potential cheaper than usual observational activity to identify and assess suitable areas. Here, we present a case study for both energy resources assessment from satellite in harbors. [ABSTRACT FROM AUTHOR]

In this work, a dynamic model for the simulation of solar cooling systems employing adsorption chillers has been evaluated. The model, realised with the commercial software TRNSYS, has been implemented to quantify the effect of different operational and design parameters on the overall performances of solar cooling systems in three different Italian cities (Milan, Rome, Messina). An economic analysis has been performed for an optimised system, in order to evaluate the payback time of the different solutions compared to a traditional air conditioning system, considering also the state incentives introduced since 2012. [ABSTRACT FROM AUTHOR]

Within the framework of the IEA Energy in Buildings and Communities Programme's Annex 56 (Cost effective energy and carbon emissions optimization in building renovation), generic calculations have been carried out to investigate the balance, synergies and trade-offs between renewable energy measures on the one hand, and energy efficiency measures on the other hand. The assessment was carried out for Austria, Denmark, Italy, Norway, Portugal, Sweden, Switzerland, and Spain. Results of this investigation show that in many cases, the cost-optimal renovation package for energy efficiency measures on the building envelope in a given building is the same regardless of the type of energy carrier being used. Furthermore, a switch to renewable energy sources has been found to reduce emissions more strongly than energy efficiency measures, often also at lower costs. [ABSTRACT FROM AUTHOR]

Driven 1 by decreasing prices for photovoltaic (PV) systems and incentive programs of different governments almost 100 GW of PV and over 100 GW of wind turbines (WT) have been integrated in the European power system today (2014). In some areas, the electricity generation already exceeds the demand, pushing the existing transport infrastructure to its limits in certain hours. In order to reach the European Commission's targets for 2050, the system integration will at some point require flexibility sources independent of conventional generation in order to keep today's standard in security of supply. There are several sources of flexibility. Together these flexibility sources will ensure the match of demand and supply at any given time. Energy storage systems can provide this flexibility by shifting of load in time while transmission grids provide the shift of load in space. Up to a certain extent, transmission capacity and storage capacity can replace each other, i.e. storage can reduce the load on transmission infrastructure by mitigating local peaks in load and/or generation. For the transition to a fully renewable energy system in 2050, major changes have to be achieved in the structure of the power supply system. The simulation tool GENESYS is a holistic approach to optimize the allocation and size of different generation technologies, storage systems and transnational grids of a European power system. The source code for the simulation tool is available free of charge under a public license. It can be freely parameterized by the user which allows the study of different electricity systems under the users’ assumptions with regard to load, generation potential and cost structure of the different system components. This publication will give an introduction to the simulation framework, the system model and the optimization strategy. Optimization results obtained with GENESYS for a fully renewable electricity system and a cost structure expected for 2050 will be presented together with sensitivity analyses investigating the main assumptions. The focus is the optimal allocation of PV and WT in a European electricity system, the resulting demand for storage capacities of different technologies and the capacity of the overlay grid. [ABSTRACT FROM AUTHOR]

This work aims to provide an intelligent low cost router system for hybrid system composed with solar, wind and batteries energy sources. The system is assisted by the electric-grid, in which according to the priority order fixed in the energy sources, provides the management of the power. This system is governed by a microcontroller with event display operations, allowing a non-interrupted feeding. It can be used especially in city or isolated sites. A parametric study of the system and simulation have been developed to highlight the proposed control strategy, the sizing of the hybrid system assisted by the electric-grid, applied to a dwelling electric charge consumption up to 3000W/day. The current work is crowned by the realization of the intelligent router system connected upstream of a single-phase DC/AC inverter to power the alternative current load for accommodation. [ABSTRACT FROM AUTHOR]

Abstract: Fossil fuel importing as well as exporting countries of the MENA region have recognized their enormous potential of power generation by renewable energy (RE) technologies and the associated benefit for their national budgets, and therefore have formulated ambitious targets for RE deployment. However, only few countries have a detailed master plan that shows how RE technologies can be integrated efficiently into their existing power plant portfolio. Capacity expansion of RE and conventional technologies must be adjusted and optimized in order to minimize total generation costs of the entire system while maintaining security of supply. Within the last three years, DLR has developed the capacity expansion and unit commitment optimization model REMix-CEM (Renewable Energy Mix – Capacity Expansion Model) in order to support authorities of the MENA region in the process of integrating RE technologies efficiently in the short-term and transforming their strongly growing fossil-fuel dominated power systems of today towards higher RE shares. REMix-CEM optimizes the capacity expansion of conventional and RE technologies from a state-owned utility perspective starting from the existing power plant portfolio by modeling the hourly performance of each single existing and candidate unit. The paper presents an overview of the developed methodology as well as the characteristics and capabilities of REMix-CEM by presenting a case study for the electricity sector of the Hashemite Kingdom of Jordan for the years 2013 – 2020. [Copyright &y& Elsevier]

Abstract: Net Zero-Energy Buildings Performance has gained more attention since the publication in 2010 of the EPBD recast [1]. Successful implementation of such an ambitious target depends on a great variety of factors. With a literature full of theoretical advice and a building industry rife with myths about the value of technologies, the present study intend to unveil an sustainable framework for sharing insights into NetZEB methodology applied in an Portuguese office building, Solar XXI, based on the authors experience in the ongoing research carried out within International Energy Agency SHC Task 40 - ECBCS Annex 52, “Towards Net Zero Energy Solar Buildings” [Copyright &y& Elsevier]

Abstract: The integration of renewable energy into the existing energy supply system is a core challenge regarding the successful realization of the German “Energiewende”. One concept to integrate decentralized regenerative power generators is a virtual power plant that operates many small facilities as one power plant. Essential parts of the concept are controllable loads and generators to reduce the impact of volatile energy resource – like wind power stations – on operational planning. Power-to-Heat-Systems (P2H) are one possible technology that can be used to a limited extent as a controllable load. The P2H-system as a component of virtual power plants is capable of supplying flexibility due to various possible operation strategies. This flexibility can either be used for ancillary services (primary, secondary and tertiary ancillary services), to provide schedule energy or for balancing group management. This paper presents a modeling approach for P2H systems as a component of virtual power plants with a high share of renewable energies. The operation strategies are evaluated with respect to economic and technical aspects and uncertainties in generation and load. The operation strategies of P2H systems are shown with regard to market integration of renewable energies within a virtual power plant and the provision of ancillary services. [Copyright &y& Elsevier]

Abstract: Investors in the electricity supply industry are spoilt for choice when considering capital-intensive investments in alternative power plants. Although such kind of decision-making problems can already be very complicated due to multiple financial risks, complexity rises further if there is the possibility that the investment can be postponed. This flexibility causes a so-called ‘value of waiting’ which is forfeited as soon as the investment is made (the “real option” is exercised). In our study with representative data for Europe/Germany, we use such a model in order to find the optimal investment decision in a situation where the electric utility has the choice between an IGCC power plant (with and without CCS), a combined gas and steam power plant with CCS, and an offshore wind farm. We compare the option value for the case that each technology is available individually, or in combination with other technologies. Finally, we consider the influence of subsidies for renewables, which can strongly promote the diffusion of renewable energy technologies and, therefore, reduce the value of CCS power plants. [Copyright &y& Elsevier]

Abstract: Agricultural activity needs electricity and oil products. Given the economic and ecological problems, there is a need to resort to the use of renewable energies which are free and non-polluting and efficient equipments that consume less electricity in farms. In this sense, this study focuses on reducing both types of energy consumption in the farms whose activities are based mainly on animal farming and irrigation by feeding from a grid-connected system using a PV generator and power grid. All devices used in the studied agricultural farm and the all agricultural activities practiced in this agricultural farm such as irrigation, livestock and conservation of farming products in the summer, has guided our choice for this pilot farm. From this point of view, this case can be generalized for northern Algeria farms and for worldwide sites witch have the same sunning conditions. Thus, the ultimate objective is to make power generating farms in Chlef (Algeria). [Copyright &y& Elsevier]

Abstract: Singapore has a steady rise in its electricity demand. The Singaporean electricity supply system relies so far heavily on fossil fuels, especially gas and oil, which are both mainly imported from Malaysia and Indonesia. This makes the electricity system in Singapore rather vulnerable to price variations and possible political conflicts with neighbouring countries. A short term solution is the construction of a LNG (liquefied natural gas) terminal which opens supply options to many sources in the world. In the long term, renewable energies such as photovoltaics will certainly be introduced into the Singapore''s energy system in a more significant way. This paper discusses the possibility to produce substantial amounts of electricity by solar photovoltaics (PV). In addition, the integration of electromobility in Singapore is analysed. Using PV and electric vehicles (EV), the future primary energy demand and CO2 emissions in Singapore could be reduced significantly. The paper will describe the TIMES (The Integrated MARKAL (Market Allocation) EFOM (Energy Flow Optimisation Model) System) model for Singapore which is developed within the project TUM CREATE (Technische Universität München Campus for Research Excellence and Technological Enterprise). TUM CREATE is a research programme sponsored by the Singapore National Research Foundation (NRF). One research goal of a sub-project in TUM CREATE is to develop scenarios of the future energy demand and energy supply in Singapore under various boundary conditions, especially oil and gas prices or policies to reduce import dependencies etc. All upstream and downstream sectors of the energy system, including traffic and heavy industry like refineries, will be part of the developed model. First results about the impact of PV and electromobility on Singapore''s primary energy demand and CO2 emissions are presented here. [Copyright &y& Elsevier]

The urbanized surface of the old continents could be double in little more than a century due to the transit of the _world from villages to cities (according to the UN) beside the rapid growing in the world population, these will lead _to large numbers of environmental problems, one of these problems is that the energy consumption per person will _increase so more energy will be produced. ^pElectricity from fossil fuels such as oil, coal and natural gas negatively affect the environment at each step from production till consumption, and relaying mainly on these resources of energy to apply this new huge demand will lead to producing more CO2 gas in the atmosphere which will case rising of earth temperature in a rapid rate while electricity generated using sources other than fossil fuel reduces the environmental impacts. Buildings consumes approximately 39% of the energy and 74% of the electricity produced annually in the United States (according to LEED BD+C version 3), and as a rule of thumb the better the energy performance of a building, the fewer greenhouse gases are emitted, So relying on renewable energies to supply urban areas with the power needed is the solution for this problem and is considered an important approach for our cities to be more sustainable. The major shift in the vision of sustainable cities is the potential of buildings to produce energy. This will entail a whole host of solutions (solar, wind power and so forth) that will make cities more interesting as well as sustainable. And in this paper we will try to introduce the main parameters and considerations of these renewable energies specially the wind energy which can affect the form of the city and the important dimensions that should be taken into consideration when designing a new sustainable city. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays, renewable energies have taken a special role in power systems and most of distributed generations (DGs) in power systems also utilize these types of energy resources. Their advantage, including the use of renewable energies which are not polluting environment and owning endless nature, the use of these resources to produce electrical energy in the world is increasing. A problem with such generators is the unwanted islanding phenomenon. In this paper, a new technique to detect islanding conditions has been proposed. The performance of the proposed method based on passive methods is much more appropriate than that of previous methods. The simulation results performed in MATLAB, clearly show improved operation of this method. [Copyright &y& Elsevier]