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  • 1.
    Abolhosseini, Shahrouz
    et al.
    College of Engineering, TEMEP, Seoul National University, Seoul, South Korea.
    Heshmati, Almas
    Jönköping University, Jönköping International Business School, JIBS, Economics, Finance and Statistics.
    The main support mechanisms to finance renewable energy development2014In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 40, p. 876-885Article, review/survey (Refereed)
    Abstract [en]

    Considering that the major part of greenhouse gases is carbon dioxide, there is a global concern aimed at reducing carbon emissions. In addition, major consumer countries are looking for alternative sources of energy to avoid the impact of higher fossil fuel prices and political instability in the major energy supplying countries. In this regard, different policies could be applied to reduce carbon emissions, such as enhancing renewable energy deployment and encouraging technological innovation and the creation of green jobs. This study compares three main support mechanisms employed by governments to finance renewable energy development programs: feed-in-tariffs, tax incentives, and tradable green certificates. Considering that many of the promising technologies to deploy renewable energy require investment in small-scale energy production systems, these mechanisms could be used to enhance renewable energy development at the desired scale. Employing a carbon emission tax or emission trading mechanism could be considered ideal policies to mitigate emissions at the lowest cost. The comparison of feed-in-tariffs and renewable portfolio standard policies showed that the former is good when a policy to develop renewable energy sources with a low level of risk for investors is considered. However, the latter is an appropriate policy when a market view policy is applied by the government. Finally, considering technological progress and the cost reduction for power generation by renewable energy sources, we suggest that support mechanism policies should be reconsidered from the financial point of view. (C) 2014 Elsevier Ltd. All rights reserved.

  • 2.
    Ackermann, Thomas
    et al.
    KTH, Superseded Departments.
    Söder, Lennart
    KTH, Superseded Departments.
    An overview of wind energy-status 20022002In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 6, no 1-2, p. 67-128Article, review/survey (Refereed)
  • 3.
    Ackermann, Thomas
    et al.
    KTH, Superseded Departments.
    Söder, Lennart
    KTH, Superseded Departments.
    Wind energy technology and current status: a review2000In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 4, no 4, p. 315-374Article, review/survey (Refereed)
  • 4.
    Aftab, A.
    et al.
    Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia.
    Ismail, Abdul Razak
    Faculty of Chemical and Energy Engineering, Universiti Teknologi Malaysia.
    Ibupoto, Zafar
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Akeiber, Hussein J.
    Faculty of Mechanical Engineering, Universiti Teknologi Malaysia.
    Malghani, M.G.K.
    Department of Environmental Management and Policy, BUITEMS Quetta, Pakistan.
    Nanoparticles based drilling muds a solution to drill elevated temperature wells: a review2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 76, p. 1301-1313Article in journal (Refereed)
    Abstract [en]

    Demand of the oil and gas energy is increasing very drastically. Conventional hydrocarbon reservoirs contain below the sealing cap rock (shale) and easily move towards wellbore are at the depletion stage. Therefore, drilling engineers in collaboration with mud engineers, geologists and geophysicists are looking for innovative materials to drill unconventional hydrocarbons reservoir which are distributed at the basin scale and cannot approach easily. Geo-thermal energy wells and most of unconventional reservoirs are occurred at high pressure high temperature (HPHT) conditions. Conventional micro-macro organic drilling mud additives with heat insulator in nature can minimize efficiency while drilling HPHT wells. Oil-based muds (OBM) are strictly restricted due to high toxic level and poor emulsion stability at HT. However, this review suggests that addition of macro size organic particles and inorganic nanoparticles can enhance rheological performance, reduce filtrate loss volume and improve shale inhibition characteristics of environmental friendly water-based mud (WBM). Despite an impressive amount of experimental work has been done over drilling additives and their effect over rheological and shale inhibition, taking into account their literature review are rare. In addition, there is no review work of the knowledge gained to date. This work will hope fully trigger further development and new research topics in the area of drilling muds system.

  • 5.
    Aghaali, Habib
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Internal Combustion Engines. KTH, School of Industrial Engineering and Management (ITM), Centres, Competence Center for Gas Exchange (CCGEx).
    Ångström, Hans-Erik
    KTH, School of Industrial Engineering and Management (ITM), Machine Design (Dept.), Internal Combustion Engines. KTH, School of Industrial Engineering and Management (ITM), Centres, Competence Center for Gas Exchange (CCGEx).
    A review of turbocompounding as a waste heat recovery system for internal combustion engines2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 49, p. 813-824Article in journal (Refereed)
    Abstract [en]

    Internal combustion engines waste a large amount of fuel energy through their exhausts. Various technologies have been developed for waste heat recovery such as turbocompounds, Rankine bottoming cycles, and thermoelectric generators that reduce fuel consumption and CO2 emissions. Turbocompounding is still not widely applied to vehicular use despite the improved fuel economy, lower cost, volume, and complexity higher exhaust gas recirculation driving capability and improved transient response. This paper comprehensively reviews the latest developments and research on turbocompounding to discover important variables and provide insights into the implementation of a high-efficiency turbocompound engine. Attention should be paid to the optimization of turbocompound engines and their configurations because the major drawback of this technology is additional exhaust back-pressure, which leads to higher pumping loss in the engines. Applying different technologies and concepts on turbocompound engines makes the exhaust energy recovery more efficient and provides more freedom in the design and optimization of the engines. Turbine efficiency plays an important role in the recovery of the wasted heat so turbine design is a crucial issue in turbocompounding. In addition, variability in geometry and rotational speed of power turbines allows for more efficient turbocompound engines in different operating conditions. The conclusion drawn from this review is that turbocompounding is a promising technology for reducing fuel consumption in the coming decades in both light- and heavy-duty engines.

  • 6.
    Akhlaghi, Shahin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials. Scania CV AB, Sweden.
    Gedde, Ulf W.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Hedenqvist, Mikael S.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Brana, Maria T. Conde
    Bellander, Martin
    Deterioration of automotive rubbers in liquid biofuels: A review2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 43, p. 1238-1248Article, review/survey (Refereed)
    Abstract [en]

    Concerns over the fast depletion of fossil fuels, environmental issues and stringent legislation associated with petroleum-based fuels have triggered a shift to bio-based fuels, as an alternative to meet the growing energy demand in the transportation sector. However, since conventional automobile fuel systems are adapted to petroleum-based fuels, switching to biofuels causes a severe deterioration in the performance of currently used rubber components. The degradation of the rubber materials in biofuels is complicated by the presence of different additives in biofuels and rubber compounds, by oxidation of biofuels and by the effects of thermomechanical loadings in the engine. This paper presents a comprehensive review of the effects of different types of biofuels, particularly biodiesel and bioethanol, on the physical, mechanical, morphological and thermal properties of elastomers under different exposure conditions. In addition, the literature data available on the variation of rubbers' resistance to biofuels with the changes in their monomer type and composition, cure system and additives content was also studied. The review essentially focuses on the compatibility of biofuels with acrylonitrile butadiene rubber, fluoroelastomers, polychloroprene rubber and silicon rubber, as the most commonly used automotive rubbers coming into contact with fuels during their service. The knowledge summarized in this study can help to develop a guideline on the selection of rubber for automotive parts designed to withstand biofuels.

  • 7.
    Allard, Ingrid
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hassan, Osama A. B.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Methods for energy analysis of residential buildings in Nordic countries2013In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 22, p. 306-318Article, review/survey (Refereed)
    Abstract [en]

    To meet the goals of the directive 2010/31/EU on the energy performance of buildings, the building sector in Europe now faces a transition towards more energy efficient buildings. Research and development of new energy solutions and technology will be necessary for the transition and the importance of analyzing building energy performance increases. This paper aims to review and evaluate different methods that are commonly used to analyze energy performance in residential buildings in Nordic countries, primarily in Sweden, Norway and Finland. A short international review of regulations is also included. The goal is to find commonly used methods and possibilities for the future. The introduced methods are summarized, categorized and compared based on their advantages and disadvantages. Although the three Nordic countries have similar climate conditions and building traditions, the review shows relatively large variations in the definitions of energy performance for residential buildings, as well as variations in how measurements and calculations are used in the methods for energy performance analysis. In the conducted review, methods, or parts of methods, are also found to be used. The methods used to analyze energy performance are found to be more similar than the concepts of energy performance itself in the three countries. These aspects may be considered in further work to develop an international policy practice for energy performance of residential buildings in cold climate.

  • 8.
    Almssad, Asaad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Almusaed, Amjad
    Albasrah University, Albasrah, Iraq.
    Environmental reply to vernacular habitat conformation from a vast areas of Scandinavia2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 48, p. 825-834Article in journal (Refereed)
    Abstract [en]

    There are many original ideas and useful system inputs embedded in the building of human settlements in Scandinavian regions, where the landscape and habitat are strongly interconnected. A cold climate and strong winds are the most prominent risks that affect habitats. The Longhouse is the foremost traditional habitat in the Scandinavian region, dating back to the Iron Age, 2000 BC. This study examines the influence of climate on the conformation of habitats. Climate had a solid impact on the conceptions of habitat form and internal space. Wind and extreme temperatures had firming consequences on the housing arrangements, layouts, orientations, and building materials used in the construction process. Habitats from this region were located in an optimal arrangement, and the south orientation was used effectively. This investigation will provide an evaluative interpretation and analysis of the real facts of vernacular habitats in the context of energy efficiency and ecological concepts, considering human settlement patterns, architectural creation and building material uses. (C) 2015 Elsevier Ltd. All rights reserved.

  • 9.
    Amara, Sofiane
    et al.
    Université de Tlemcen, BP 119 Tlemcen.
    Baghdadli, Tewfik
    Université de Tlemcen, BP 119 Tlemcen.
    Knapp, Samuel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordell, Bo
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Legionella Disinfection by Solar Concentrator System2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 70, p. 786-792Article in journal (Refereed)
    Abstract [en]

    The current study concerns the fundamental problems of Legionnaires disease. Four decades after Legionnaires' bacteria was first identified there is still a low level of clinical awareness. Humans are infected by inhalation of aerosolized water and/or soil contaminated with the bacteria. Several control methods are available for water disinfection: biocide, ultraviolet light sterilization, copper-silver ionization, ozonation etc. but only thermal treatment can completely eliminate Legionella, which is killed almost instantly at 70 °C. The current paper describes Legionella disinfection by a solar concentrator combined with a heat recovery system that reduces the heat demand. Though this study is made for a small system (160 l of hot water per day) the system can be enlarged (more hot water and more solar collector area) and the results are thus valid also for such larger systems. Here experiments of water treatment by a solar concentrator are summarized and analyzed where the temperature exceeds 80 °C at the outlet of the heat exchanger.

  • 10.
    Andersson, Elias
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Karlsson, Magnus
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Thollander, Patrik
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Paramonova, Svetlana
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Energy end-use and efficiency potentials among Swedish industrial small and medium-sized enterprises - A dataset analysis from the national energy audit program2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 93, p. 165-177Article, review/survey (Refereed)
    Abstract [en]

    Improving energy efficiency in industry is recognized as one of the most vital activities for the mitigation of climate change. Consequently, policy initiatives from governments addressing both energy-intensive and small and medium-sized industry have been enacted. In this paper, the energy end-use and the energy efficiency potential among industrial small and medium-sized companies participating in the Swedish Energy Audit Program are reviewed. The three manufacturing industries of wood and cork, food products and metal products (excluding machinery and equipment) are studied. A unique categorization of their production processes energy end-use is presented, the results of which show that the amount of energy used in various categories of production processes differ between these industries. This applies to support processes as well, highlighting the problem of generalizing results without available bottom-up energy end-use data. In addition, a calculation of conservation supply curves for measures related to production processes is presented, showing that there still remains energy saving potential among companies participating in the Swedish Energy Audit Program. However, relevant data in the database used from the Swedish Energy Audit Program is lacking which limits the conclusions that can be drawn from the conservation supply curves. This study highlights the need to develop energy policy programs delivering high-quality data. This paper contributes to a further understanding of the intricate matters of industrial energy end-use and energy efficiency measures.

  • 11.
    Anukam, Anthony
    et al.
    Univ Ft Hare, South Africa.
    Mamphweli, Sampson
    Univ Ft Hare, South Africa..
    Reddy, Prashant
    Durban Univ Technol, South Africa..
    Meyer, Edson
    Univ Ft Hare, South Africa..
    Okoh, Omobola
    Univ Ft Hare, South Africa..
    Pre-processing of sugarcane bagasse for gasification in a downdraft biomass gasifier system: A comprehensive review2016In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 66, p. 775-801Article, review/survey (Refereed)
    Abstract [en]

    The processing of sugarcane bagasse as a potential feedstock for efficient energy production has attracted a great deal of attention in the sugarcane industry, which has traditionally inefficiently burned bagasse in boilers for steam and electricity generation. Alternative technologies for more efficient utilisation of bagasse for energy production within the industry has also been hindered by the high degree of complexity involved in bagasse handling and pre-processing before it can be utilised as an energy feedstock. This can be attributed to unfavourable characteristics of mill-run bagasse, which includes low bulk and energy densities, a wide range of particle sizes and shapes as well as high moisture content. Gasification is regarded as one of the most promising energy recovery technologies for the widespread use of biomass because of its higher efficiency when compared to the combustion technology commonly used by the sugarcane industry. There has been a strong drive to identify efficient pre-processing methods that can be applied to bagasse to make it a suitable feedstock for energy production in thermochemical conversion systems. This work provides a comprehensive review on the pre-processing of bagasse for gasification, and the gasification technology options for its conversion into energy, with a particular emphasis on the downdraft gasification technology. (C) 2016 The Authors. Published by Elsevier Ltd.

  • 12.
    Averfalk, Helge
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Ingvarsson, Paul
    ÅF, Division Industry, Stockholm, Sweden.
    Persson, Urban
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Gong, Mei
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Large heat pumps in Swedish district heating systems2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 79, p. 1275-1284Article in journal (Refereed)
    Abstract [en]

    Power-to-heat solutions like heat pumps and electric boilers are foreseen to be possible future tools to stabilise international power markets with high proportions of variable power supply. Temporary low cost electricity can be used for heat generation at times with high availability of wind and solar power through substitution of ordinary heat supply, hence contributing to increased energy system sustainability. Power-to-heat installations in district heating systems are competitive due to low specific investment and installation costs for large electric boilers, heat pumps, and heat storages. Several large-scale heat pumps were installed in Swedish district heating systems during the 1980s, since a national electricity surplus from new nuclear power existed for some years. The aim of this paper is to summarise the accumulated operation experiences from these large Swedish heat pumps to support and facilitate planning of future power-to-heat solutions with heat pumps in district heating systems. Gained experiences consider; installed capacities, capacity utilisation, heat sources used, refrigerant replacements, refrigerant leakages, and wear of mechanical components. The major conclusion is that many of the large thirty-year-old heat pumps are still in operation, but with reduced capacity utilisation due to internal competition from waste and biomass cogeneration plants in the district heating systems.

  • 13.
    Azuatalam, Donald
    et al.
    Univ Sydney, Sch Elect & Informat Engn, Sydney, NSW, Australia..
    Paridari, Kaveh
    KTH, School of Electrical Engineering and Computer Science (EECS), Electric Power and Energy Systems.
    Ma, Yiju
    Univ Sydney, Sch Elect & Informat Engn, Sydney, NSW, Australia..
    Foerstl, Markus
    Tech Univ Munich, Inst Elect Energy Storage Technol, Munich, Germany..
    Chapman, Archie C.
    Univ Sydney, Sch Elect & Informat Engn, Sydney, NSW, Australia..
    Verbic, Gregor
    Univ Sydney, Sch Elect & Informat Engn, Sydney, NSW, Australia..
    Energy management of small-scale PV-battery systems: A systematic review considering practical implementation, computational requirements, quality of input data and battery degradation2019In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 112, p. 555-570Article, review/survey (Refereed)
    Abstract [en]

    The home energy management problem has many different facets, including economic viability, data uncertainty and quality of strategy employed. The existing literature in this area focuses on individual aspects of this problem without a detailed, holistic analysis of the results with regards to practicality in implementation. In this paper, we fill this gap by performing a comprehensive comparison of seven different energy management strategies, each with different levels of practicality, sophistication and computational requirements. We analyse the results in the context of these three characteristics, and also critique the modelling assumptions made by each strategy. Our analysis finds that using a more sophisticated energy management strategy may not necessarily improve the performance and economic viability of the PV-battery system due to the effects of modelling assumptions, such as the treatment of uncertainties in the input data and battery degradation effects.

  • 14.
    Bahaj, AbuBakr S.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Generating electricity from the oceans2011In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 15, no 7, p. 3399-3416Article in journal (Refereed)
    Abstract [en]

    Ocean energy has many forms, encompassing tides, surface waves, ocean circulation, salinity and thermal gradients. This paper will considers two of these, namely those found in the kinetic energy resource in tidal streams or marine currents, driven by gravitational effects, and the resources in wind-driven waves, derived ultimately from solar energy. There is growing interest around the world in the utilisation of wave energy and marine currents (tidal stream) for the generation of electrical power. Marine currents are predictable and could be utilised without the need for barrages and the impounding of water, whilst wave energy is inherently less predictable, being a consequence of wind energy. The conversion of these resources into sustainable electrical power offers immense opportunities to nations endowed with such resources and this work is partially aimed at addressing such prospects. The research presented conveys the current status of wave and marine current energy conversion technologies addressing issues related to their infancy (only a handful being at the commercial prototype stage) as compared to others such offshore wind. The work establishes a step-by-step approach that could be used in technology and project development, depicting results based on experimental and field observations on device fundamentals, modelling approaches, project development issues. It includes analysis of the various pathways and approaches needed for technology and device or converter deployment issues. As most technology developments are currently UK based, the paper also discusses the UK's financial mechanisms available to support this area of renewable energy, highlighting the needed economic approaches in technology development phases. Examination of future prospects for wave and marine current ocean energy technologies are also discussed.

  • 15.
    Bao, Haiyan
    et al.
    Changsha Univ Sci & Technol, Sch Hydraul Engn, Changsha.; Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Yang, Jiandong
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Zhao, Guilian
    PowerChina Chengdu Engn Corp Ltd, Chengdu.
    Zeng, Wei
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan 430072, Hubei, Peoples R China..
    Liu, Yanna
    Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Yang, Weijia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity. Wuhan Univ, State Key Lab Water Resources & Hydropower Engn S, Wuhan.
    Condition of setting surge tanks in hydropower plants - A review2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, p. 2059-2070Article, review/survey (Refereed)
    Abstract [en]

    Hydropower plays an important role in the safe, stable and efficient operation of power systems, especially with current trends toward renewable energy systems. The total global potential of gross, technical, economic, and exploitable hydropower are still enormous in the future, and the developments of new hydropower stations (HPSs) are of great importance. For constructions of new HPSs, the condition of setting surge tanks (CSST) is crucial for various perspectives, e.g. safety, stability and economy of HPSs. In this review, the CSST are summarized and analyzed from the three aspects: regulation assurance, operation stability, and the regulation quality, with an aim of providing a reference and guidance for research and engineering applications regarding surge tanks. Upstream and downstream surge tanks in conventional HPSs and pumped storage power stations are all included. Moreover, a comprehensive comparison of CSST under different conditions is conducted. One of the main focuses of this review is on Chinese studies, for introducing many meaningful results written in Chinese to more readers all over the world.

  • 16. Bartoli, A.
    et al.
    Hamelin, L.
    Rozakis, S.
    Borzęcka, M.
    Brandão, Miguel
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Coupling economic and GHG emission accounting models to evaluate the sustainability of biogas policies2019In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 106, p. 133-148Article in journal (Refereed)
    Abstract [en]

    The aim of this study is to evaluate and quantify the impacts of different biogas and related policies on the agricultural sector as well as their performance in terms of climate change mitigation and associated costs. To do so we coupled the partial equilibrium approach simulating the market clearing process with the perspective of Life Cycle Assessment of GHG applying it to the well-documented Lombardy case. Results show that the recent Italian biogas policy – prompting manure utilization and reducing the average subsidy per kWh – effectively increased the environmental sustainability of the system, which only now seems able to counteract global warming. Synergies are observed when the recent Common Agricultural Policy greening reform is simultaneously considered by the model.

  • 17. Bird, Lori
    et al.
    Lew, Debra
    Milligan, Michael
    Carlini, E. Maria
    Estanqueiro, Ana
    Flynn, Damian
    Gomez-Lazaro, Emilio
    Holttinen, Hannele
    Menemenlis, Nickie
    Orths, Antje
    Eriksen, Peter Borre
    Smith, J. Charles
    Söder, Lennart
    KTH, School of Electrical Engineering (EES), Electric power and energy systems.
    Sorensen, Poul
    Altiparmakis, Argyrios
    Yasuda, Yoh
    Miller, John
    Wind and solar energy curtailment: A review of international experience2016In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 65, p. 577-586Article, review/survey (Refereed)
    Abstract [en]

    Greater penetrations of variable renewable generation on some electric grids have resulted in increased levels of curtailment in recent years. Studies of renewable energy grid integration have found that curtailment levels may grow as the penetration of wind and solar energy generation increases. This paper reviews international experience with curtailment of wind and solar energy on bulk power systems in recent years, with a focus on eleven countries in Europe, North America, and Asia. It examines levels of curtailment, the causes of curtailment, curtailment methods and use of market based dispatch, as well as operational, institutional, and other changes that are being made to reduce renewable energy curtailment.

  • 18.
    Bolund, Björn
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Bernhoff, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Leijon, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Flywheel energy and power storage systems2007In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 11, no 2, p. 235-258Article in journal (Refereed)
    Abstract [en]

    For ages flywheels have been used to achieve smooth operation of machines. The early models where purely mechanical consisting of only a stone wheel attached to an axle. Nowadays flywheels are complex constructions where energy is stored mechanically and transferred to and from the flywheel by an integrated motor/generator. The stone wheel has been replaced by a steel or composite rotor and magnetic bearings have been introduced. Today flywheels are used as supplementary UPS storage at several industries world over. Future applications span a wide range including electric vehicles, intermediate storage for renewable energy generation and direct grid applications from power quality issues to offering an alternative to strengthening transmission. One of the key issues for viable flywheel construction is a high overall efficiency, hence a reduction of the total losses. By increasing the voltage, current losses are decreased and otherwise necessary transformer steps become redundant. So far flywheels over 10 kV have not been constructed, mainly due to isolation problems associated with high voltage, but also because of limitations in the power electronics. Recent progress in semi-conductor technology enables faster switching and lower costs. The predominant part of prior studies have been directed towards optimising mechanical issues whereas the electro technical part now seem to show great potential for improvement. An overview of flywheel technology and previous projects are presented and moreover a 200 kW flywheel using high voltage technology is simulated.

  • 19.
    Bundschuh, Jochen
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Land and Water Resources Engineering. University of Southern Queensland, Australia.
    Ghaffour, Noreddine
    Mahmoudi, Hacene
    Goosen, Mattheus
    Mushtaq, Shahbaz
    Hoinkis, Jan
    Low-cost low-enthalpy geothermal heat for freshwater production: Innovative applications using thermal desalination processes2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 43, p. 196-206Article, review/survey (Refereed)
    Abstract [en]

    The study is dedicated to exploring different types of low-cost low-enthalpy geothermal and their potential integration with conventional thermal-based water desalination and treatment technologies to deliver energy efficient, environmentally friendly solutions for water desalination and treatment, addressing global water crises. Our in-depth investigation through reviews of various low-enthalpy geothermal and conventional thermal-based technologies suggest that the geothermal option is superior to the solar option if low-cost geothermal heat is available because it provides a constant heat source in contrast to solar. Importantly, the stable heat source further allows up-scaling ( >1000 m(3)/day), which is not currently possible with solar. Solar-geothermal hybrid constellations may also be suitable in areas where both sources are available. The review also discovers that the innovative Membrane distillation (MD) process is very promising as it can be used for many different water compositions, salinity and temperature ranges. Either the geothermal water itself can be desalinated/treated or the geothermal heat can be used to heat feed water from other sources using heat exchangers. However, there are only few economic analyses for large-scale MD units and these are based on theoretical models using often ;uncertain assumptions resulting in a large variety of results.

  • 20.
    Bundschuh, Jochen
    et al.
    KTH. National Centre for Engineering in Agriculture, Australia .
    Maity, Jyoti Prakash
    Geothermal arsenic: Occurrence, mobility and environmental implications2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 42, p. 1214-1222Article, review/survey (Refereed)
    Abstract [en]

    Arsenic (As) contamination in geothermal systems has been identified in many areas of the world. Arsenic mobilization from rocks and mineral phases into geothermal fluids depends on available As sources, geochemical conditions and microbiological activity. In deep geothermal reservoirs As mobilization is predominantly from As-bearing pyrite at temperatures of 150-250 degrees C, and at higher temperatures also from arsenopyrite. Highest As concentrations, mostly in the range of thousands to tens of thousands of mu g/L and in case of Los Humeros (Mexico) even of up to 162,000 mu g/L are found in volcanic geothermal systems whereas in low- and high-enthalpy sedimentary geothermal systems they reach only about 2000 mu g/L. At many sites, uprising geothermal waters contaminate shallow water resources. From the geothermal springs, those with NaCl water type have the highest As concentrations; these waters correspond to original reservoir waters which were not significantly altered during its ascent. In the geothermal reservoir and deeper parts of hydrothermal system, As is predominantly present as neutral H3As(III)O-3 (arsenius acid) and under sulfidic conditions also as thioarsenites; close to the earth's surface oxidation through atmospheric oxygen to As(V) species may occur; however, this is a slow process. As(III) emerging in geothermal springs is oxidized quickly through microbial catalysis and often most As is present as As(V), at a distance of few meters from the spring outlet. This review highlights the occurrence and distribution of geothermal As worldwide, its sources and its mobilization and the presence of different As species in geothermal fluids considering different geological settings and processes involving geothermal fluids rising from deep geothermal reservoirs to the earth's surface where it may mix with shallow groundwater or surface waters and contaminate these resources. The microbial diversity of hot spring environments which plays an important role to mobilize the As by oxidation and reduction process in the geothermal system is also addressed.

  • 21.
    Chen, Jianyong
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Jarall, Sad
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Havtun, Hans
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Palm, Björn
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    A review on versatile ejector applications in refrigeration systems2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 49, p. 67-90Article, review/survey (Refereed)
    Abstract [en]

    This paper presents a useful knowledge of ejector working principles and the versatility and diversity of its applications in refrigeration technologies. Various ejector refrigeration systems are described with the associated studies, and categorized as conventional ejector refrigeration system, advanced ejector refrigeration systems, combined refrigeration systems and ejector enhanced vapor compression systems. This paper also presents the important elements that affect the optimum performance of the ejector system, and the results of studies that have generally confirmed their energy saving, great potential for large refrigerating temperature scales and performance enhancement.

  • 22. Cheng, Chuntian
    et al.
    Chen, Fu
    Li, Gang
    Ristić, Bora
    Mirchi, Ali
    Stockholm University, Faculty of Science, Department of Physical Geography. University of Texas at El Paso, USA.
    Tu, Qiyu
    Madani, Kaveh
    Stockholm University, Faculty of Science, Department of Physical Geography. Imperial College London, United Kingdom.
    Reform and renewables in China: The architecture of Yunnan's hydropower dominated electricity market2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 94, p. 682-693Article, review/survey (Refereed)
    Abstract [en]

    Reforms currently under way in China's electricity markets bear important implications for its decarbonization objectives. The southwestern province of Yunnan is among the provinces piloting the current iteration of power market reforms. As such, lessons from Yunnan will inform future market reform and renewable energy policies in China and potentially elsewhere. The dominance of hydropower in Yunnan's energy portfolio and the particular transmission constraints it faces, offer an interesting case study of the challenges of decarbonization. We report on market architecture reforms and aggregate market data collected from the Yunnan Power Exchange. We review four elements in the reformed market architecture. Market pricing rules, transitional quantity controls, the generation rights market, and inter-provincial trade. The specifics of market reform reflect a compromise between decarbonization, inter-provincial competition, grid security and development objectives and contribute to understanding of how the dual transitions of hydropower decarbonization and market liberalization interact. We conclude on six insights regarding the role of the grid operator, security checks on trade, integration of cascade hydropower, the inclusion of renewables in the generation rights market, price controls, and market participant price uncertainty.

  • 23. Coronado, Christian Rodriguez
    et al.
    Tuna, Celso Eduardo
    Zanzi, Rolando
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Vane, Lucas F.
    Silveira, Jose Luz
    Development of a thermoeconomic methodology for optimizing biodiesel production. Part II: Manufacture exergetic cost and biodiesel production cost incorporating carbon credits, a Brazilian case study2014In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 29, p. 565-572Article, review/survey (Refereed)
    Abstract [en]

    The purpose of this study is to carry on a thermoeconomic analysis at a biodiesel production plant considering the irreversibilities in each step (part I: biodiesel plant under study and functional thermoeconomic diagram [1]), making it possible to calculate the thermoeconomic cost in US$/kWh and US$/1 of the biodiesel production, and the main byproduct generated, glycerin, incorporating the credits for the CO2 that is not emitted into the atmosphere (carbon credits). Assuming a sale price for both the biodiesel and the byproduct (glycerin), the annual revenue of the total investment in a plant with a capacity of 8000 t/year of biodiesel operating at 8000 h/year was calculated. The variables that directly or indirectly influence the final thermoeconomic cost include total annual biodiesel production, hours of operation, manufacturing exergy cost, molar ratio in the transesterification reaction, reaction temperature and pressure in the process. Depending on the increase or decrease in sale prices for both biodiesel and glycerin, the payback is going to significantly increase or decrease. It is evident that, in exergy terms, the sale of glycerin is of vital importance in order to reduce the biodiesel price, getting a shorter payback period for the plant under study.

  • 24. Coronado, Christian Rodriguez
    et al.
    Tuna, Celso Eduardo
    Zanzi, Rolando
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Vane, Lucas F.
    Silveira, Jose Luz
    Development of a thermoeconomic methodology for the optimization of biodiesel production-Part I: Biodiesel plant and thermoeconomic functional diagram2013In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 23, p. 138-146Article in journal (Refereed)
    Abstract [en]

    This work developed a methodology that uses the thermoeconomic functional diagram applied for allocating the cost of products produced by a biodiesel plant. The first part of this work discusses some definitions of exergy and thermoeconomy, with a detailed description of the biodiesel plant studied, identification of the system functions through Physical Diagram, calculation of the irreversibilities of the plant, construction of the Thermoeconomic Functional Diagram and determination of the expressions for the plant's exergetic functions. In order to calculate the exergetic increments and the physical exergy of certain flows in each step, the Chemical Engineering Simulation Software "HYSYS 3.2" was used. The equipments that have the highest irreversibilities in the plant were identified after the exergy calculation. It was also found that the lowest irreversibility in the system refers to the process with a molar ratio of 6:1 and a reaction temperature of 60 degrees C in the transesterification process. In the second part of this. work (Part II), it was calculated the thermoeconomic cost of producing biodiesel and related products, including the costs of carbon credits for the CO2 that is not released into the atmosphere, when a percentage of biodiesel is added to the petroleum diesel used by Brazil's internal diesel fleet (case study).

  • 25.
    Cuvilas, Carlos Alberto
    et al.
    Swedish University for Agricultural Sciences (SLU), Department of Energy and Technology, Uppsala, Sweden .
    Jirjis, R.
    Swedish University for Agricultural Sciences (SLU), Department of Energy and Technology, Sweden .
    Lucas, C.
    Energy situation in Mozambique: A review2010In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 14, no 7, p. 2139-2146Article, review/survey (Refereed)
    Abstract [en]

    The need to increase energy security and promote development, especially in rural areas has forced many developing countries in southern Africa, like Mozambique to take several actions toward development of several infrastructures and legislations for production and use of liquid biofuels. The main objective of this study is to present the energy situation in Mozambique and assess the potential for energy generation from widely available renewable sources including residues from agricultural crops and forest industry. The country is endowed with great potential for biofuels, solar, hydro and wind energy production. The energy production today is, however, far from fulfilling energy needs of the country, and the majority of people are still not benefiting from these resources. The potential of total residues from agricultural sector and forest industry is estimated to be around 128 PJ. This amount of energy covers almost half of the combined production of charcoal and firewood which amounted to approximately 298 PJ in 2006. However, such amount of energy resources is wasted and is not visible on national energy statistics.

  • 26.
    Darmani, Anna
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics. Universidad Politécnica de Madrid, Spain .
    Arvidsson, Niklas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability and Industrial Dynamics.
    Hidalgo, Antonio
    Albors, Jose
    What drives the development of renewable energy technologies?: Toward a typology for the systemic drivers2014In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 38, p. 834-847Article, review/survey (Refereed)
    Abstract [en]

    At present, governments are embarking on the ambitious undertaking of increasing their countries' market share of renewable energy. Political ambitions, however, are just one of the driving forces for energy companies' to engage in innovative climate projects. Energy companies' perceptions of business opportunities are dependent on a set of factors that influence their innovation ambitions. This research operationalizes previous work on the main drivers of the establishment of Renewable Energy Technologies (RETs), with the aim of presenting an overview of the typical systemic drivers within a technological innovation system (TIS) framework. This leads to the proposal of a comprehensive typology and categorization of drivers of RETs. The typology is validated empirically by analyzing data on the development of four types of RETs (wind, solar, biomass and wave energy) in eight European countries (EU-7 and Ireland). The study's results shed light on the multilateral drivers behind the development of RETs. Furthermore, a cross-case comparative study reveals the differences between drivers of RETs and the patterns of these drivers in different countries.

  • 27. de Carvalho, Carolina Monteiro
    et al.
    Silveira, Semida
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Energy and Climate Studies, ECS.
    La Rovere, Emilio Lebre
    Iwama, Allan Yu
    Deforested and degraded land available for the expansion of palm oil for biodiesel in the state of Para in the Brazilian Amazon2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 44, p. 867-876Article in journal (Refereed)
    Abstract [en]

    This paper maps the availability of deforested and degraded land in the state of Para in the eastern Amazon and discusses the feasibility of using this land for the expansion of palm crops for biodiesel production. The ultimate objective is to highlight land that is suitable for palm oil and its availability/distribution, so that the palm oil expansion envisaged by the Brazilian Government's Sustainable Palm Oil Program can be achieved in a sustainable way. The analysis is developed with the support of geoprocessing techniques that pull data together from different sources, including the Agroecological Zoning (ZAE) developed for palm oil in Brazil and degraded land data. The analysis identifies some of the challenges faced when planning and monitoring the expansion of palm oil in the Amazon, including the need for an operational concept to identify and use degraded land.

  • 28. Duan, Zhiyin
    et al.
    Zhan, Changhong
    Zhang, Xingxing
    De Montfort University.
    Mustafa, Mahmud
    Zhao, Xudong
    Alimohammadisagvand, Behrang
    Hasan, Ala
    Indirect evaporative cooling: Past, present and future potentials2012In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 16, no 9, p. 6823-6850Article in journal (Refereed)
    Abstract [en]

    This paper reported a review based study into the Indirect Evaporative Cooling (IEC) technology, which was undertaken from a variety of aspects including background, history, current status, concept, standardisation, system configuration, operational mode, research and industrialisation, market prospect and barriers, as well as the future focuses on R&D and commercialisation. This review work indicated that the IEC technology has potential to be an alternative to conventional mechanical vapour compression refrigeration systems to take up the air conditioning duty for buildings. Owing to the continuous progress in technology innovation, particularly the M-cycle development and associated heat and mass transfer and material optimisation, the IEC systems have obtained significantly enhanced cooling performance over those the decade ago, with the wet-bulb effectiveness of greater than 90% and energy efficiency ratio (EER) up to 80. Structure of the IEC heat and mass exchanger varied from flat-plate-stack, tube, heat pipe and potentially wave-form. Materials used for making the exchanger elements (plate/tube) included fibre sheet with the single side water proofing, aluminium plate/tube with single side wicked setting (grooved, meshed, toughed etc), and ceramic plate/tube with single side water proofing. Counter-current water flow relevant to the primary air is considered the favourite choice; good distribution of the water stream across the wet surface of the exchanger plate (tube) and adequate (matching up the evaporation) control of the water flow rate are critical to achieving the expected system performance. It was noticed that the IEC devices were always in combined operation with other cooling measures and the commonly available IEC related operational modes are (1) IEC/DEC system; (2) IEC/DEC/mechanical vapour compression system; (3) IEC/desiccant system; (4) IEC/chilled water system; and (5) IEC/heat pipe system. The future potential operational modes may also cover the IEC-inclusive fan coil units, air handle units, cooling towers, solar driven desiccant cycle, and Rankine cycle based power generation system etc. Future works on the IEC technology may focus on (1) heat exchanger structure and material; (2) water flowing, distribution and treatment; (3) incorporation of the IEC components into conventional air conditioning products to enable combined operation between the IEC and other cooling devices; (4) economic, environment and social impacts; (5) standardisation and legislation; (6) public awareness and other dissemination measures; and (7) manufacturing and commercialisation. All above addressed efforts may help increase the market ratio of the IEC to around 20% in the next 20 years, which will lead to significant saving of fossil fuel consumption and cut of carbon emission related to buildings.

  • 29.
    Eid, Cherrelle
    KTH, School of Electrical Engineering (EES).
    Managing electric flexibility from Distributed Energy Resources: A review of incentives for market design2016In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 64, p. 237-247Article in journal (Refereed)
    Abstract [en]

    In many electric systems worldwide the penetration of Distributed Energy Resources (DER) at the distribution levels is increasing. This penetration brings in different challenges for electricity system management; however if the flexibility of those DER is well managed opportunities arise for coordination. At high voltage levels under responsibility of the system operator, trading mechanisms like contracts for ancillary services and balancing markets provide opportunities for economic efficient supply of system flexibility services. In a situation with smart metering and real-time management of distribution networks, similar arrangements could be enabled for medium- and low-voltage levels. This paper presents a review and classification of existing DER as flexibility providers and a breakdown of trading platforms for DER flexibility in electricity markets.

  • 30.
    Ejdemo, Thomas
    et al.
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Söderholm, Patrik
    Luleå University of Technology, Department of Business Administration, Technology and Social Sciences, Social Sciences.
    Wind power, regional development and benefit-sharing: The case of Northern Sweden2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 47, p. 476-485Article in journal (Refereed)
    Abstract [en]

    This paper addresses the question of how investments in wind power can promote regional development and employment, as well as how different benefit-sharing instruments (e.g., community funds etc.) can be used to strengthen the positive impacts. The objectives of the paper are to provide: (a) a survey of previous regional-economic assessments of wind power projects; as well as (b) a quantitative assessment of the employment impacts of an ongoing wind farm investment in the Swedish county of Norrbotten under different benefit-sharing scenarios. Our model-based input–output analysis confirms many of the findings of previous research, such as significant construction work impacts, especially in the presence of local manufacturing. The analysis also illustrates that in the absence of any benefit-sharing mechanism, the employment impacts for Norrbotten during the operating phase will be modest (with an employment multiplier of 1.4). However, even if a relatively low share of the wind power revenues is assumed to accrue to the local government this would have significant positive impacts on employment rates. For this reason, additional research on various types of benefit-sharing instruments is called for, including studies of the associated challenges and trade-offs

  • 31.
    Ekström, Rickard
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Ekergård, Boel
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Leijon, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Electrical damping of linear generators for wave energy converters: A review2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 42, p. 116-128Article, review/survey (Refereed)
    Abstract [en]

    The electrical damping of point-absorber wave energy converters is crucial to optimize the power output. Many circuit topologies have been proposed, but the possible increase in power absorption must be weighed against parameters such as cost, reliability and control system complexity. In this paper, the known electrical damping circuits are categorized, described and compared. The hydrodynamic damping of the buoy is covered, and how a linear generator can be used as a power take-off unit to apply a damping force. A qualitative comparison of the circuits is presented in the end. A more complex and costly power electronics system may be viable for wave energy converters (WECs) of large-scale power rating. However, for farm operation with small-scale WECs, a simpler and passive damping may be more suitable.

  • 32.
    Enrichi, Francesco
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.
    Quandt, Alexander
    School of Physics and Materials for Energy Research Group, University of the Witwatersrand, Johannesburg.
    Righini, Giancarlo C.
    Historical Museum of Physics and Study & Research Centre “Enrico Fermi”.
    Plasmonic enhanced solar cells: Summary of possible strategies and recent results2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 82, no 3, p. 2433-2439Article in journal (Refereed)
    Abstract [en]

    Plasmonic structures for light manipulation at sub-wavelength scale have received great interest in the field of photovoltaic (PV) solar cells for their potential to significantly enhance the cell's efficiency.

    The performance of any solar cell is determined by the capability to absorb incoming light and produce electric charges, which, in turn, has a number of limiting factors. One is related to the ever-reducing size and acceptance angle of the active region. Another is the limited spectral sensitivity of the active material, which cannot make use of significant parts of the solar spectrum.

    Correspondingly, the energy harvesting may be improved in two ways, namely by adopting light trapping schemes and by exploiting spectral modification processes to shift frequencies of the solar spectrum, which are initially not absorbed, into the region of maximum absorption of the cell.

    Plasmonic nanoparticles (NPs) can give a significant boost to both these aspects, by scattering and concentrating the electromagnetic field into the active region of the device, and by doing that within specific spectral regions, which can be properly tuned by optimizing the size, shape, distribution of the plasmonic NPs, and by choosing the right surrounding medium.

    During the last ten years, many papers have been published on very specific issues, but also on general properties of plasmonics applied to solar cells, with a strong increase between 2006 and 2012, followed by a period of significant, but stable, literature productivity. Given these premises, an organized and schematic summary of the main strategies and of the recent results on the field is given in this review, where different plasmonic approaches are compared and discussed, also by recalling specific examples from the literature and providing a few key conclusions to understand the main aspects and the future perspectives of the field.

  • 33.
    Fiedler, Frank
    Dalarna University, School of Technology and Business Studies, Environmental Engineering.
    The state of the art of small-scale pellet-based heating systems and relevant regulations in Sweden, Austria and Germany2004In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 8, no 3, p. 201-221 Article in journal (Refereed)
    Abstract [en]

    The emphasis of this report is on the actual technology of small-scale pellet combustion units and important regulations concerning emissions and pellets. Wood as a heating source has a long tradition in Sweden, but the use of compressed wood pellets in domestic stoves and boilers is rather new. Based on a literature survey, information from manufacturers and test institutes, this report gives an overview about existing technology and investigates how mature it is already. Some comparisons were made to similar heating units in Austria, where this technique is also widely used. It could be seen that the Austrian boilers are more sophisticated including a high level of comfort for the user. On the other hand the simpler Swedish boilers are significantly less expensive, and it is questionable if Swedish costumers are willing to pay for the higher comfort. Relevant regulations concerning emissions and fuel quality are also reported and compared between Sweden, Germany and Austria. In addition some interesting non-official certificates and environmental labels are presented. These give an outlook to future, probably more stringent, regulations.

  • 34.
    Fischer, David
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Fraunhofer Institute for Solar Energy Systems, Germany.
    Madani, Hatef
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    On heat pumps in smart grids: A review2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 70, p. 342-357Article, review/survey (Refereed)
    Abstract [en]

    This paper investigates heat pump systems in smart grids, focussing on fields of application and control approaches that have emerged in academic literature. Based on a review of published literature technical aspects of heat pump flexibility, fields of application and control approaches are structured and discussed. Three main categories of applications using heat pumps in a smart grid context have been identified: First stable and economic operation of power grids, second the integration of renewable energy sources and third operation under variable electricity prices. In all fields heat pumps - when controlled in an appropriate manner - can help easing the transition to a decentralized energy system accompanied by a higher share of prosumers and renewable energy sources. Predictive controls are successfully used in the majority of studies, often assuming idealized conditions. Topics for future research have been identified including: a transfer of control approaches from simulation to the field, a detailed techno-economic analysis of heat pump systems under smart grid operation, and the design of heat pump systems in order to increase flexibility are among the future research topics suggested.

  • 35. Gasparatos, A.
    et al.
    von Maltitz, G. P.
    Johnson, Francis X.
    Stockholm University, Stockholm Environment Institute.
    Lee, L.
    Mathai, M.
    Puppim de Oliveira, J. A.
    Willis, K. J.
    Biofuels in sub-Sahara Africa: Drivers, impacts and priority policy areas2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 45, p. 879-901Article in journal (Refereed)
    Abstract [en]

    There has been a growing interest in jatropha- and sugarcane-based biofuels across Sub-Sahara Africa. Biofuel expansion in the region reflects policy concerns related to energy security, poverty alleviation and economic development. However, biofuels have also been linked to numerous environmental and socioeconomic impacts such as GHG emissions, water availability/pollution, deforestation, biodiversity loss, poverty alleviation, energy security, loss of access to land and food security to name just a few. Yet there is (a) an insufficient understanding of these impacts (and their synergies) in Sub-Sahara Africa, and (b) a lack of policies that could regulate the biofuel sector and ensure its viability while at the same time preventing its negative impact. The aim of this literature review is to synthesize the current knowledge about biofuel impacts in Africa and to identify priority policy areas that should be targeted for enhancing biofuel sustainability in the continent. The findings of this review indicate that biofuel impacts can be positive or negative depending on several factors such as the feedstock, the environmental/socio-economic context of biofuel production, and the policy instruments in place during biofuel production, use and trade. In most cases there are significant trade-offs but at least part of the negative impacts can be mitigated through careful planning. The incomplete and piecemeal understanding of these trade-offs combined with agronomic, institutional and market failures are currently the most important barriers for the viability and sustainability of biofuel investments in the continent.

  • 36.
    Goyal, Rahul
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics. Indian Institute of Technology, Department of Mechanics & Industrial Engineering, Roorkee .
    Gandhi, Bhupendra K.
    Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee .
    Cervantes, Michel
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Fluid and Experimental Mechanics.
    PIV measurements in Francis turbine: A review and application to transient operations2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, no 2, p. 2976-2991Article in journal (Refereed)
    Abstract [en]

    Penetration of solar and wind energy into the grid network has raised the concern for grid stability which is generally balanced by operating the hydropower plants over a wide range. This results in several issues, such as rotor-stator interaction (RSI), vortex breakdown, rotating vortex rope (RVR), pressure shocks, vibration, and noise which may lead to failure. Particle Image Velocimetry (PIV) has been used to understand several physical mechanisms in the flow at various operating conditions. A non-negligible uncertainty may arise in the measurements due to calibration, abbreviation, and distortion of the light. Various parameters such as laser sheet thickness, particle type, particle size, particle density, camera resolution, image size and number of images may affect the quality of the measurements. In the present work, a review of PIV measurements performed in hydraulic turbines, mainly Francis, has been carried out. The objective is to develop an experimental set up to perform steady and transient measurements on a model Francis turbine. A maximum deviation of 1.8% in absolute velocity is estimated in the present study as compared to 2–3% reported in the previously performed measurements on Francis turbines. The repeatability of transient measurements is also investigated by extracting two velocity points on a PIV plane

  • 37.
    Grabbe, Mårten
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Lalander, Emilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Lundin, Staffan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Leijon, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    A review of the tidal current energy resource in Norway2009In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 13, no 8, p. 1898-1909Article, review/survey (Refereed)
    Abstract [en]

    As interest in renewable energy sources is steadily on the rise, tidal current energy is receiving more and more attention from politicans, industrialists, and academics. In this article, the conditions for and potential of tidal currents as an energy resource in Norway are reviewed. There having been a relatively small amount of academic work published in this particular field, closely related topics such as the energy situation in Norway in general, the oceanography of the Norwegian coastline, and numerical models of tidal currents in Norwegian waters are also examined. Two published tidal energy resource assessments are reviewed and compared to a desktop study made specifically for this review based on available data in pilot books. The argument is made that tidal current energy ought to be an important option for Norway in terms of renewable energy.

  • 38. Grottera, Carolina
    et al.
    Barbier, Carine
    Sanches Pereira, Alessandro
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Research Group on Bioenergy, Institute of Energy and Environment, University of São Paulo (USP), São Paulo, Brazil.
    Weiss de Abreu, Mariana
    Uchôa, Christiane
    Tudeschini, Luís Gustavo
    Cayla, Jean-Michel
    Nadaud, Franck
    Pereira Jr, Amaro Olimpio
    Cohen, Claude
    Teixeira Coelho, Suani
    Linking electricity consumption of home appliances and standard of living: A comparison between Brazilian and French households2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 94, p. 877-888Article in journal (Refereed)
    Abstract [en]

    Solutions based exclusively on technology are unlikely to fully deliver a transition towards a low-carbon society. Shifts in consumption patterns and lifestyles associated with technological solutions are essential to achieve safe GHG concentration levels. Considering households' consumption patterns, residential electricity consumption represents a major issue, as it is closely related to lifestyle choices and living standards. In this context, this paper discusses how specific electricity requirements may vary across different deciles of living standard in Brazil and France. The present evaluation is based on specific electricity consumption and its corresponding carbon dioxide emissions for different home appliances used for food conservation, lighting, daily chores (e.g. cloth washing), as well as information and leisure. Results ratify, on the one hand, the significant income gap existing between French and Brazilian households. On the other hand, they show that differences regarding specific electricity requirements in the two countries are lower than intuitively expected. Hence, they evidence a converging trend in electricity requirements between the two countries, especially among higher income deciles.

  • 39.
    Gueymard, Christian A.
    et al.
    Solar Consulting Serv, Colebrook, NH USA.
    Bright, Jamie M.
    Australian Natl Univ, Fenner Sch Environm & Soc, Canberra, ACT, Australia.
    Lingfors, David
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Habte, Aron
    Natl Renewable Energy Lab, Golden, CO USA.
    Sengupta, Manajit
    Natl Renewable Energy Lab, Golden, CO USA.
    A posteriori clear-sky identification methods in solar irradiance time series: Review and preliminary validation using sky imagers2019In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 109, p. 412-427Article, review/survey (Refereed)
    Abstract [en]

    This study examines all known methods that have been proposed in the literature to identify clear-sky periods in historical solar irradiance time series. Two different types of clear-sky detection (CSD) methods are discussed: those (16 total) that attempt to isolate periods of 1-min or more cloudless conditions, and those (5 total) that only attempt to detect clear-sun periods. All methods are found to rely on a diversity of inputs and on a variety of tests that typically examine the smoothness of the temporal variation of global and/or direct irradiance. Using samples of a few days with variable cloudiness, it is shown that these methods all have obvious strengths and weaknesses. Although this justifies a detailed validation to determine which method(s) could be best suited in the practice of solar radiation modeling or other applications, the current lack of appropriate equipment at high-quality reference radiometric stations prevents such an endeavor. Only a preliminary study is conducted here at seven stations of the SURFRAD network in the U.S., where 1-min irradiance measurements are available, along with sky data from a Total Sky Imager (TSI). The many limitations of the latter prevent its data to be considered "ground truth" here. Nevertheless, the comparison of the results from all CSD methods and 1.2 million TSI observations from all SURFRAD sites provides important qualitative and quantitative information, using a variety of performance indicators. Overall, two CSD methods appear more robust and are recommended, pending better high-resolution and high-performance cloud observations from modern sky cameras to redo these tests.

  • 40.
    Gunasekara, Saman Nimali
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Martin, Viktoria
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Chiu, Justin NingWei
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Phase equilibrium in the design of phase change materials for thermal energy storage: State-of-the-art2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 73, p. 558-581Article, review/survey (Refereed)
    Abstract [en]

    This paper presents a review of phase equilibrium as a tool for accurately identifying suitable blended phasechange materials (PCMs) to be used for thermal energy storage (TES). PCM storage increases the overall energyefficiency for many applications, however, high cost and complex phase change phenomena in blends oftenundermine the benefits. The study of phase equilibrium as derived from phase diagrams is the key to solve theseissues. It enables the evaluation of PCM-suitability through indication of temperature-composition points, e.g.congruent melting compositions, eutectics and peritectics. To clearly stake out the opportunities of a phaseequilibrium-based design methodology, this paper reviews the state-of-the-art based on findings from fourdecades (1977–2016). On one hand, eutectics, salts-based systems, fatty acids, and alkanes dominate theexisting PCM literature. Here peritectics have often been erroneously praised as suitable PCMs despite the manyproblems depicted from a phase equilibrium point of view. On the other hand, the most PCM-ideal congruentmelting systems, as well as the blends of polyols, fats, metal alloys and organic-inorganic combinations lack fullattention. This work brings forward the knowledge on these insufficiently explored yet extremely suitable phaseequilibrium characteristics. In addition, comprehensive PCM-design thermal properties of these various blendsare presented, as a basis to further extensive explorations, and material category-based predictions.

  • 41.
    Gustavsson, Leif
    et al.
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Haus, Sylvia
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Lundblad, Mattias
    Swedish University of Agricultural Sciences.
    Lundström, Anders
    Swedish University of Agricultural Sciences.
    Ortiz, Carina A.
    Swedish University of Agricultural Sciences.
    Sathre, Roger
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Truong, Nguyen Le
    Linnaeus University, Faculty of Technology, Department of Built Environment and Energy Technology.
    Wikberg, Per-Erik
    Swedish University of Agricultural Sciences.
    Climate change effects of forestry and substitution of carbon-intensive materials and fossil fuels2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 67, p. 612-624Article in journal (Refereed)
    Abstract [en]

    We estimate the climate effects of directing forest management in Sweden towards increased carbon storage in forests with more land set-aside for protection, or towards increased forest production for the substitution of carbon-intensive materials and fossil fuels, relative to a reference case of current forest management. We develop various scenarios of forest management and biomass use to estimate the carbon balances of the forest systems, including ecological and technological components, and their impacts on the climate in terms of radiative forcing. The scenario with increased set-aside area and the current level of forest residue harvest resulted in lower cumulative carbon emissions compared to the reference case for the first 90 years, but then showed higher emissions as reduced forest harvest led to higher carbon emissions from energy and material systems. For the reference case of current forest management, increased harvest of forest residues gave increased climate benefits. The most climatically beneficial alternative, expressed as reduced cumulative radiative forcing, in both the short and long terms is a strategy aimed at high forest production, high residue recovery rate, and high efficiency utilization of harvested biomass. Active forest management with high harvest levels and efficient forest product utilization will provide more climate benefit, compared to reducing harvest and storing more carbon in the forest.

  • 42.
    Göransson, Kristina
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Söderlind, Ulf
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    He, Jie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Review of syngas production via biomass DFBGs2011In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 15, no 1, p. 482-492Article, review/survey (Refereed)
    Abstract [en]

    Production of high-quality syngas from biomass gasification in a dual fluidised bed gasifier (DFBG) has made a significant progress in R&D and Technology demonstration. An S&M scale bio-automotive fuel plant close to the feedstock resources is preferable as biomass feedstock is widely sparse and has relatively low density, low heating value and high moisture content. This requires a simple, reliable and cost-effective production of clean and good quality syngas. Indirect DFBGs, with steam as the gasification agent, produces a syngas of high content H2 and CO with 12-20 MJ/mn3 heating value. A good quality syngas from DFBGs can be obtained by optimised design and operation of the gasifier, by the use of active catalytic bed materials including internal reforming of tars and methane, and finally by a downstream cleaning process. This article reviews the whole process from gasification to high quality syngas. © 2010 Elsevier Ltd. All rights reserved.

  • 43.
    Hadin, Åsa
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Eriksson, Ola
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    Hillman, Karl
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Building, Energy and Environmental Engineering, Environmental engineering.
    A review of potential critical factors in horse keeping for anaerobic digestion of horse manure2016In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 65, p. 432-442Article, review/survey (Refereed)
    Abstract [en]

    Keeping horses causes environmental impacts through the whole chain from feed production to manure. According to national statistics, the number of horses in Sweden is currently 360,000 and is continuing to increase. This result in increasing amounts of horse manure that has to be managed and treated, which is currently done using practices that cause local, regional, and global environmental impacts. However, horse manure and its content of nutrients and organic material could be a useful fertiliser for arable land and a substrate for renewable energy production as biogas. The aim of the paper is to identify and describe potentially critical factors in horse keeping determining the amount (total mass) and characteristics (nutrient content and biodegradability) of horse manure, and thus the potential for anaerobic digestion. A systematic combining approach is used as a structural framework for reviewed relevant literature. All factors identified are expressed as discrete choices available to the horse keeper. In all, 12 different factors were identified: type and amount of feed, type and amount of bedding, mucking out regime, residence time outdoors, storage type and residence time of manure in storage, spreading and soil conditions, and transport distance and type of vehicle fuel used. Managing horses in terms of these factors is of vital importance in reducing the direct environmental impacts from horse keeping and in making horse manure attractive as a substrate for anaerobic digestion. The results are also relevant to environmental systems analysis, where numerical calculations are employed and different biogas system set-ups are compared to current and other treatments. In such assessments, the relevance and importance of the critical factors identified here and corresponding conditions can be examined and the most promising system set-up can be devised.

  • 44.
    Haikola, Simon
    et al.
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Anshelm, Jonas
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    Power production and environmental opinions: Environmentally motivated resistance to wind power in Sweden2016In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 57, p. 1545-1555Article in journal (Refereed)
    Abstract [en]

    Historically, every form of large scale power production in Sweden has given rise to organised, sustained and partly successful resistance motivated by environmental arguments. Since wind power is identified by the Swedish Parliament as an important energy source for the future and the wind power industry is expected to expand on a large scale, there is reason to believe that the already existing environmental opposition to wind power will continue to grow and will attempt to limit or at least partly obstruct the wind power expansion. In order to facilitate an understanding of this opposition and its possibility to significantly influence future wind power expansion in Sweden, this paper draws upon previous research on the opposition towards hydropower, nuclear power and biomass in Sweden, and discusses these findings in relation to previous research on wind power opposition.

  • 45. Hammar, Linus
    et al.
    Gullström, Martin
    Stockholm University, Faculty of Science, Department of Ecology, Environment and Plant Sciences.
    Dahlgren, Thomas G.
    Asplund, Maria E.
    Braga Goncalves, Ines
    Molander, Sverker
    Introducing ocean energy industries to a busy marine environment2017In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 74, p. 178-185Article, review/survey (Refereed)
    Abstract [en]

    The immense energy potential of the oceans is being increasingly recognized the world over, at the same time the integrity of marine ecosystems is challenged by pressure from multiple human activities. For good reasons environmental licensing procedures are precautionary and new industries must declare their detrimental impacts and provide mitigation measures. New ocean energy industries target renewable energy sources thus, on a grand scale, partly mitigating climate change. However, on-site environmental impacts are yet to be established. In this review we compare ocean energy industries with a wide range of conventional, better understood, human activities and outline environmental risks and research priorities. Results show that ocean energy systems are thought to incur many pressures, some familiar and others with yet unknown effects. Particular uncertainties regard ocean thermal energy conversion (OTEC) and large fast-moving turbines. Ocean energy industries should not be considered in isolation because the significance of environmental impacts depend on the full spectra of human activities in each area. Marine spatial planning provides a platform for holistic assessments and may facilitate the establishment of ocean energy industries, as long as risk-related uncertainties are reduced.

  • 46.
    Haraldsson, Joakim
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Johansson, Maria
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    Review of measures for improved energy efficiency in production-related processes in the aluminium industry: From electrolysis to recycling2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 93, p. 525-548Article, review/survey (Refereed)
    Abstract [en]

    The aluminium industry is facing a challenge in meeting the goal of halved greenhouse gas emissions by 2050, while the demand for aluminium is estimated to increase 2–3 times by the same year. Energy efficiency will play an important part in achieving the goal. The paper’s aim was to investigate possible production-related energy efficiency measures in the aluminium industry. Mining of bauxite and production of alumina from bauxite are not included in the study. In total, 52 measures were identified through a literature review. Electrolysis in primary aluminium production, recycling and general measures constituted the majority of the 52 measures. This can be explained by the high energy intensity of electrolysis, the relatively wide applicability of the general measures and the fact that all aluminium passes through either electrolysis or recycling. Electrolysis shows a higher number of emerging/novel measures compared to the other processes, which can also be explained by its high energy intensity. Processing aluminium with extrusion, rolling, casting (shape-casting and casting of ingots, slabs and billets), heat treatment and anodising will also benefit from energy efficiency. However, these processes showed relatively fewer measures, which might be explained by the fact that to some extent, these processes are not as energy demanding compared, for example, to electrolysis. In many cases, the presented measures can be combined, which implies that the best practice should be to combine the measures. There may also be a future prospect of achieving carbon-neutral and coal-independent electrolysis. Secondary aluminium production will be increasingly important for meeting the increasing demand for aluminium with respect to environmental and economic concerns and strengthened competitiveness. Focusing on increased production capacity, recovery yields and energy efficiency in secondary production will be pivotal. Further research and development will be required for those measures designated as novel or emerging.

  • 47.
    Heier, Johan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology. Högskolan Dalarna, Energi och miljöteknik.
    Bales, Chris
    Högskolan Dalarna, Energi och miljöteknik.
    Martin, Viktoria
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
    Combining Thermal Energy Storage with Buildings: A Review2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 42, p. 1305-1325Article, review/survey (Refereed)
    Abstract [en]

    Thermal Energy Storage (TES) has been a topic of research for quite some time and has proven to be a technology that can have positive effects on the energy efficiency of a building by contributing to an increased share of renewable energy and/or reduction in energy demand or peak loads for both heating and cooling. There are many TES technologies available, both commercial and emerging, and the amount of published literature on the subject is considerable. Literature discussing the combination of thermal energy storage with buildings is however lacking and it is therefore not an easy task to decide which type of TES to use in a certain building. The goal of this paper is to give a comprehensive review of a wide variety of TES technologies, with a clear focus on the combination of storage technology and building type. The results show many promising TES technologies, both for residential and commercial buildings, but also that much research still is required, especially in the fields of phase change materials and thermochemical storage.

  • 48.
    Heier, Johan
    et al.
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology. KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Bales, Chris
    Dalarna University, School of Technology and Business Studies, Energy and Environmental Technology.
    Martin, Viktoria
    Department of Energy Technology, KTH.
    Combining Thermal Energy Storage with Buildings: A Review2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 42, p. 1305-1325Article in journal (Refereed)
    Abstract [en]

    Thermal Energy Storage (TES) has been a topic of research for quite some time and has proven to be a technology that can have positive effects on the energy efficiency of a building by contributing to an increased share of renewable energy and/or reduction in energy demand or peak loads for both heating and cooling. There are many TES technologies available, both commercial and emerging, and the amount of published literature on the subject is considerable. Literature discussing the combination of thermal energy storage with buildings is however lacking and it is therefore not an easy task to decide which type of TES to use in a certain building. The goal of this paper is to give a comprehensive review of a wide variety of TES technologies, with a clear focus on the combination of storage technology and building type. The results show many promising TES technologies, both for residential and commercial buildings, but also that much research still is required, especially in the fields of phase change materials and thermochemical storage.

  • 49.
    Hesaraki, Arefeh
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Holmberg, Sture
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Fluid and Climate Technology.
    Haghighat, Fariborz
    Seasonal thermal energy storage with heat pumps and low temperatures in building projects-A comparative review2015In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 43, p. 1199-1213Article, review/survey (Refereed)
    Abstract [en]

    Application of seasonal thermal energy storage with heat pumps for heating and cooling buildings has received much consideration in recent decades, as it can help to cover gaps between energy availability and demand, e.g. from summer to winter. This has the potential to reduce the large proportion of energy consumed by buildings, especially in colder climate countries. The problem with seasonal storage, however, is heat loss. This can be reduced by low-temperature storage but a heat pump is then recommended to adjust temperatures as needed by buildings in use. The aim of this paper was to compare different seasonal thermal energy storage methods using a heat pump in terms of coefficient of performance (COP) of heat pump and solar fraction, and further, to investigate the relationship between those factors and the size of the system, i.e. collector area and storage volume based on past building projects including residences, offices and schools.

  • 50.
    Hong, Yue
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Waters, Rafael
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Boström, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Eriksson, Mikael
    Engström, Jens
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Leijon, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
    Review on electrical control strategies for wave energy converting systems2014In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 31, p. 329-342Article, review/survey (Refereed)
    Abstract [en]

    Renewable energy techniques are now gaining more and more attention as the years pass by, not only because of the threat of climate change but also, e.g. due to serious pollution problems in some countries and because the renewable energy technologies have matured and can be depended upon an increasing degree. The energy from ocean waves bares tremendous potential as a source of renewable energy, and the related technologies have continually been improved during the last decades. In this paper, different types of wave energy converters are classified by their mechanical structure and how they absorb energy from ocean waves. The paper presents a review of strategies for electrical control of wave energy converters as well as energy storage techniques. Strategies of electrical control are used to achieve a higher energy absorption, and they are also of interest because of the large variety among different strategies. Furthermore, the control strategies strongly affect the complexity of both the mechanical and the electrical system, thus not only impacting energy absorption but also robustness, survivability, maintenance requirements and thus in the end the cost of electricity from ocean waves.

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