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The aim of this study is to investigate the possibility of enhancing the gasification process using a pre-treated biomass that presents higher heating value, higher C/O ratio and less moisture content than untreated biomass. The aim is to assess the gasification parameters that can be modified in order to achieve the best performance of the gasification system. These research studies have been carried out in collaboration with the Centre RAPSODEE (UMR CNRS 5302, IMT Ecole de mines Albi-Carmaux, France) and the Free University of Bolzano (Italy). The torrefaction of standard pellets is realized using a lab scale rotary kiln unit at RAPSODEE. On the contrary, the gasification tests are carried out at the Free University of Bozen-Bolzano by means of a fixed bed open top gasifier. The tests of pellets torrefaction has been carried out at 250°C and 270°C with two repetitions in order to obtain about 60 kg of pellets for each torrefied condition. The used feedstock is a standard French pellets produced from sawdust of oak and beech following the standard EN 14961-2 (“Wood pellets for non-industrial use”). The pellets are characterized before and after the torrefaction pre-treatment. The gasifier used for the gasification tests is an open top pilot-scale gasifier placed at the Bioenergy and Biofuel Lab of the Free University of Bolzano. The plant is an open top downdraft system, where both gas and feedstock move downward as the reactions proceed. The main difference between un-treated and torrefied pellets is the moisture content. In addition, a slight increase in terms of carbon content and LHV and a slight decrease in terms of volatile matter are observed by moving from standard to torrefied pellets. The torrefied pellets seem to reach lower performances in terms of cold gas efficiency (CGE) and char yield with respect to the standard pellets. However, the trends in terms of ER and CGE suggest that moving toward higher values of ER, higher values of CGE could be reached independently of the material used. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 403-406

Considering the challenge of evaluation of the urban environment from the energy point of view, there is plenty of room to improve the resources currently managed by users, enterprises and public institutions. The goal is to create a tool that supports in the decision making in the energy planning process in specific areas by automatically estimating the energy demand and consumption of buildings using public data and representing the results in a geo-referenced way. The tool will provide a better understanding of what the current status of the buildings is, providing these stakeholders with a larger quantity of useful data about the city environment, including not only the geometric information present in cadastre repositories, but also the data collected from the Energy Performance Certificates (EPCs). In this case, the data from the cadastre repository are combined with the EPCs for each province, with data about the demanded and consumed energy. The objective is to generate a set of buildings typologies for each province with estimated values for the demand and consumption for each building type. These typologies could be used to generate a map with the energetic values for any municipality of this province. These results can be injected into GIS (Geographic Information Systems) tools that could show these data in order to evaluate the energy demand/consumption of the municipality easing the energy planning decision-making process, or even into databases for further uses. International Journal of Sustainable Energy Planning and Management, Vol 24 (2019)

Small-scale development of renewable energy has been identified as one possible solution to meet future energy needs and is well aligned with the general European trend towards further development of community energy projects. Increased local energy production will move energy plants closer to habitation, placing aspects related to social acceptance at the center stage [1, 2]. Until recently, small hydro power [3] projects in Norway have been owned by local farmers and others with property rights to rivers. As the profitability of these projects has decreased, international investors have taken interest in SHP projects as part of their long-term investment strategy. In this paper, we study what influences social acceptance of SHP projects in Norway based on interviews and qualitative data from different SHP projects in Norway. We find that community energy projects often are attributed positive qualities when ownership is local. Thus, we argue that there is a need to consider more thoroughly how to organize ownership of small-scale renewables in the future, if it is to uphold its position as a popular and viable solution to meet future energy needs [3]. International Journal of Sustainable Energy Planning and Management, Vol. 31 (2021)

The German government aims for substituting 10·109 m3/a natural gas by upgraded biogas, also called synthetic natural gas (SNG) until 2030. Currently about 0.8·109 m3/a SNG are produced by 146 biogas plants and fed into the German gas grid [1]. A more efficient production of upgraded biogas could help to increase this number and achieve the initial aim. Two-stage pressurized fermentation promises to increase the efficiency of both the production of biogas and its upgrading. In order to evaluate the advantages of pressure and of the two-stage design on the process performance and especially on product gas composition, a process model was developed and validated. Experimentally it was shown that by increasing the pressure the methane content is significantly increased from already about 67 mol-% for the atmospheric operated two-stage fermentation up to 76 mol-% at 9 bar. The model calculations reproduced the findings and additionally reveal potential for even higher methane content in the gas by recycling decompressed liquid and/or by proper pH adjustment, both being currently investigated experimentally. Considering the power demand shows the constraints of such measures and can furthermore be used as a tool for process optimization. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 539-546

The paper presents basic information about photovoltaic cell operating principles and applied technologies. Statistical data that describes trends in photovoltaic generation development is reviewed. Information is analyzed that describes the sales of photovoltaic cells, increase in the installed capacity and development of the technology and prices. The paper comprehensively addresses the legal context of the development photovoltaics in Poland, starting from government plans for relevant programmes, and ending with an assessment of the most important regulations in EU and national law.

Charcoal production in Portugal is presently mostly based on the valorization of wood prunings from cork oak and holm oak stands. Nevertheless, since wildfire prevention became a priority in Portugal, as in other South European countries like Spain and Greece, especially after the dramatic wildfires of 2017 and 2018, urgent actions are being conducted to reduce the amount of biomass available in the forests. In addition, there is also considerable amounts of woody residues from e.g. pruning activities (olive trees, stone pine, etc.), forest management, or the control of non-native species which are rapidly increasing the amount and heterogeneity of the woody residues that are available for valorization. This has motivated the present research on whether the carbonization process can be successfully applied to valorize alternative woody biomasses not currently used on a large scale. For this purpose, slow pyrolysis experiments were carried out with ten types of wood typically found in Southern-Europe, using a fixed bed reactor that enables controlled heating of large fuel particles (50×55mm) at 1ºC/min and final temperatures within 300 to 450ºC. Apart from an evaluation of the mass balance of the process, special emphasis was given to the properties of the resulting charcoal in relation to its major market in Portugal – barbecue charcoal. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 368-376

The article describes the collection of comprehensive information on crops for energy purposes, including economic and environmental indicators based on a model solution. The applied method is based on a detailed description of conditions for the production of principal crops covering technological procedures of crop production, including individual working operations. The production inputs and outputs are derived from the register of local soil and climatic conditions in the Czech Republic. Thus, all the operational indicators for crops usable for energy generation in a particular location, i.e. in by plot, farm, cadastral territory or higher administrative unit, can be evaluated in a comprehensive manner. The data rely on the current values of economic indicators, input and output parameters that are also time evaluated with respect to the environmental indicators in line with the LCIA method of Ecoinvent company. Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 55-61

{"references": ["Miah, M.S., N.U. Ahmed, and M. Chowdhury, Optimum policy for\nintegration of renewable energy sources into the power generation\nsystem. Energy Economics, 2012. 34(2): p. 558-567.", "Moss, D.L., Kwoka, J.E. Competition policy and the transition to a lowcarbon,\nefficient electricity industry. The Electricity Journal. 2010 23 (7)", "Iran's Energy Balance, 2010, Institute for International Energy Studies\nAffiliated to Ministry of Petroleum, I.R. Iran", "CO2 Emissions from Fuel Combustion 2012, International Energy\nAgency", "Mehleri, E.D., et al., Optimal design and operation of distributed energy\nsystems: Application to Greek residential sector. Renewable Energy,\n2013. 51(0): p. 331-342", "Akorede MF, Hizam H, Rouresmaeil E. Distributed energy resources\nand benefits to the environment. Renewable and Sustainable Energy\nReviews 2010; 14:724e34.", "Alanne, K. and A. 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Bhattacharya, Optimal planning and design of a\nrenewable energy based supply system for microgrids. Renewable\nEnergy. 45(0): p. 7-15.\n[14] Moghaddas-Tafreshi, S.M., H.A. Zamani, and S.M. Hakimi, Optimal\nsizing of distributed resources in micro grid with loss of power supply\nprobability technology by using breeding particle swarm optimization.\nJournal of Renewable and Sustainable Energy, 2011. 3(4): p. 043105-17.\n[15] Handschin E, Neise F, Neumann H, Schultz R. Optimal operation of\ndispersed generation under uncertainty using mathematical\nprogramming. International Journal of Electrical Power and Energy\nSystems 2006; 28:618e26.\n[16] Ren H, Gao W. A MILP model for integrated plan and evaluation of\ndistributed energy systems. Applied Energy 2010; 87:1001e14.\n[17] Giannakoudis G, Papadopoulos AI, Seferlis P, Voutetakis S. \"Optimum\ndesign and operation under uncertainty of power systems using\nrenewable energy sources and hydrogen storage.\" International Journal\nof Hydrogen Energy 2010; 35:872\u2013891.\n[18] Geidl, Martin, et al. \"The Energy Hub\u2013A powerful concept for future\nenergy systems.\" Third annual Carnegie Mellon Conference on the\nElectricity Industry, Pittsburgh. 2007.\n[19] Geidl, Martin, and G\u00f6ranAndersson. \"Optimal power flow of multiple\nenergy carriers.\" Power Systems, IEEE Transactions on 22.1 (2007):\n145-155.\n[20] Geidl, Martin, et al. \"Energy hubs for the future.\" IEEE Power and\nEnergy Magazine 5.1 (2007): 24-30.\n[21] Geidl, Martin, and G\u00f6ran Andersson. \"A modeling and optimization\napproach for multiple energy carrier power flow.\" Power Tech, 2005\nIEEE Russia. IEEE, 2005.\n[22] Nazar, MehrdadSetayesh, and Mahmood R. Haghifam. \"Multiobjective\nelectric distribution system expansion planning using hybrid energy hub\nconcept.\" Electric Power Systems Research 79.6 (2009): 899-911.\n[23] Schulze, M., L. Friedrich, and M. Gautschi. \"Modeling and optimization\nof renewables: applying the energy hub approach.\" Sustainable Energy\nTechnologies, 2008. ICSET 2008. IEEE International Conference on.\nIEEE, 2008.\n[24] Marler, R. T. and J. S. Arora. \"Survey of multi-objective optimization\nmethods for engineering.\" Structural and multidisciplinary optimization\n2004, 26(6): 369-395\n[25] D&R, Buildings Energy Data Book, D&R International, Ltd., 2009\n[26] R. Graham, W. Chow, Technical and Economic Assessment of\nCombined Heat and Power Technologiesfor Commercial Customer\nApplications, EPRI Project Manager, 2003.\n[27] Weber C, Shah N. Optimisation based design of a district energy system\nfor an eco-town in the United Kingdom. Energy 2011; 36:1292e308.\n[28] Farid Seyyedeyn, Azadeh MaroufMashat, Ramin Roshandel, Sourena\nSattrai, Optimal design and operation of Photovoltaic-electrolyzer\nsystem using particle swarm optimization, the International journal of\nSustainable energy, published online , April 2014"]} Multi-energy systems will enhance the system reliability and power quality. This paper presents an integrated approach for the design and operation of distributed energy resources (DER) systems, based on energy hub modeling. A multi-objective optimization model is developed by considering an integrated view of electricity and natural gas network to analyze the optimal design and operating condition of DER systems, by considering two conflicting objectives, namely, minimization of total cost and the minimization of environmental impact which is assessed in terms of CO2 emissions. The mathematical model considers energy demands of the site, local climate data, and utility tariff structure, as well as technical and financial characteristics of the candidate DER technologies. To provide energy demands, energy systems including photovoltaic, and co-generation systems, boiler, central power grid are considered. As an illustrative example, a hotel in Iran demonstrates potential applications of the proposed method. The results prove that increasing the satisfaction degree of environmental objective leads to increased total cost.

District heating is considered an important component in a future highly renewable European energy system. With the turn towards developing 4th generation district heating (4GDH), the integral role of district heating in fully renewable energy systems is emphasized further. Norway is a country that is expected to play a significant role in the transition of the European energy system due to its high shares of flexible hydropower in the electricity sector. At the same time, the country is moving towards electrification in all sectors and higher shares of variable renewable electricity generation, potentially reducing the flexibility of the system. District heating has played a minor role in Norway but could potentially decrease the need for electric capacity expansion and increase the flexibility of the system. In this paper we investigate the role of 4GDH in a highly electrified future Norwegian energy system. A highly electrified scenario for the Norwegian energy system is constructed based on a step-by-step approach, implementing measures towards electrification and expansion of renewable electricity generation. Then, a 4GDH scenario is constructed for the purpose of analysing the role of 4GDH. EnergyPLAN is used for simulation. Results show that an expansion of 4GDH will increase the total system efficiency of the Norwegian energy system due to the introduction of heat savings, more efficient heating solutions and low-temperature excess heat. However, the flexibility provided from increased heat storage capacity is limited. International Journal of Sustainable Energy Planning and Management, Vol. 27 (2020): Special Issue from the 5th International Conference on Smart Energy Systems