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  • 1. Bai, Q.
    et al.
    Guo, Z.
    Li, H.
    Yang, Xiaohu
    KTH, School of Chemical Science and Engineering (CHE).
    Jin, L.
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Experimental investigation on the solidification behavior of phase change materials in open-cell metal foams2017In: Energy Procedia, Elsevier Ltd , 2017, Vol. 142, p. 3703-3708Conference paper (Refereed)
    Abstract [en]

    This study presented an experimental investigation on solidification behavior of fluid saturated in highly porous open-cell copper foams. Particular attention has been made on the effect of pore parameters (pore density and porosity) on the solidification behavior. A purposely-designed apparatus was built for experimental observations. Results showed that the copper foam had a great effect on solidification and the full solidification time can be saved up to 50%, especially preventing the decrease in solidification rate during the later stage of phase change. The smaller the porosity is, the faster the solidification rate will be. Pore density was found to have little influence upon the solidification rate. In addition, the local natural convection does exist but it has a slight effect on solidification, leading to the slant of the solid-liquid interface.

  • 2.
    Benavente Araoz, Fabian Andres
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Lundblad, Anders
    Res Inst Sweden, RISE, Div Safety & Transport Elect, SE-50462 Boras, Sweden..
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Zhang, Yang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Cabrera, Saul
    UMSA Univ Mayor San Andres, Carrera Ciencias Quim, Inst Invest Quim, La Paz, Bolivia..
    Lindbergh, Göran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Photovoltaic/battery system sizing for rural electrification in Bolivia: Considering the suppressed demand effect2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 235, p. 519-528Article in journal (Refereed)
    Abstract [en]

    Rural electrification programs usually do not consider the impact that the increment of demand has on the reliability of off-grid photovoltaic (PV)/battery systems. Based on meteorological data and electricity consumption profiles from the highlands of Bolivian Altiplano, this paper presents a modelling and simulation framework for analysing the performance and reliability of such systems. Reliability, as loss of power supply probability (LPSP), and cost were calculated using simulated PV power output and battery state of charge profiles. The effect of increasing the suppressed demand (SD) by 20% and 50% was studied to determine how reliable and resilient the system designs are. Simulations were performed for three rural application scenarios: a household, a school, and a health centre. Results for the household and school scenarios indicate that, to overcome the SD effect, it is more cost-effective to increase the PV power rather than to increase the battery capacity. However, with an increased PV-size, the battery ageing rate would be higher since the cycles are performed at high state of charge (SOC). For the health centre application, on the other hand, an increase in battery capacity prevents the risk of electricity blackouts while increasing the energy reliability of the system. These results provide important insights for the application design of off-grid PV-battery systems in rural electrification projects, enabling a more efficient and reliable source of electricity.

  • 3.
    Campana, Pietro Elia
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Wästhage, Louise
    Mälardalen Univ, Sch Business Soc & Engn, Future Energy Ctr, S-72123 Vasteras, Sweden..
    Nookuea, Worrada
    Mälardalen Univ, Sch Business Soc & Engn, Future Energy Ctr, S-72123 Vasteras, Sweden..
    Tan, Yuting
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Optimization and assessment of floating and floating-tracking PV systems integrated in on- and off-grid hybrid energy systems2019In: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 177, p. 782-795Article in journal (Refereed)
    Abstract [en]

    Considering the targets of Thailand in terms of renewable energy exploitation and decarbonization of the shrimp farming sector, this work evaluates several scenarios for optimal integration of hybrid renewable energy systems into a representative shrimp farm. In particular, floating and floating-tracking PV systems are considered as alternatives for the exploitation of solar energy to meet the shrimp farm electricity demand. By developing a dynamic techno-economic simulation and optimization model, the following renewable energy systems have been evaluated: PV and wind based hybrid energy systems, off-grid and on-grid PV based hybrid energy systems, ground mounted and floating PV based hybrid energy systems, and floating and floating-tracking PV based hybrid energy systems. From a water-energy nexus viewpoint, floating PV systems have shown significant impacts on the reduction of evaporation losses, even if the energy savings for water pumping are moderate due to the low hydraulic head. Nevertheless, the study on the synergies between water for food and power production has highlighted that the integration of floating PV represents a key solution for reducing the environmental impacts of shrimp farming. For the selected location, the results have shown that PV systems represent the best renewable solution to be integrated into a hybrid energy system due to the abundance of solar energy resources as compared to the moderate wind resources. The integration of PV systems in off-grid configurations allows to reach high renewable reliabilities up to 40% by reducing the levelized cost of electricity. Higher renewable reliabilities can only be achieved by integrating energy storage solutions but leading to higher levelized cost of electricity. Although the floating-tracking PV systems show higher investment costs as compared to the reference floating PV systems, both solutions show similar competiveness for reliabilities up to 45% due to the higher electricity production of the floating-tracking PV systems. The higher electricity production from the floating-tracking PV systems leads to a better competitiveness for reliabilities higher than 90% due to lower capacity requirements for the storage systems.

  • 4.
    Campana, Pietro Elia
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Zhang, J.
    Univ Maryland, Dept Geog Sci, College Pk, MD 20742 USA..
    Yao, T.
    Sci Syst & Applicat Inc SSAI, Lanham, MD 20706 USA.;NASA, Goddard Space Flight Ctr, Greenbelt, MD 20771 USA..
    Andersson, S.
    Swedish Meteorol & Hydrol Inst, SE-60176 Norrkoping, Sweden..
    Landelius, T.
    Swedish Meteorol & Hydrol Inst, SE-60176 Norrkoping, Sweden..
    Melton, F.
    NASA ARC CREST, Moffett Field, CA 94035 USA.;Calif State Univ Monterey Bay, Sch Nat Sci, Seaside, CA 93955 USA..
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Future Energy Ctr, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden.;KTH Royal Inst Technol, Dept Chem Engn, SE-10044 Stockholm, Sweden..
    Managing agricultural drought in Sweden using a novel spatially-explicit model from the perspective of water-food-energy nexus2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 197, p. 1382-1393Article in journal (Refereed)
    Abstract [en]

    Using a multi-disciplinary approach, this paper integrated spatial analysis with agricultural and energy system modelling to assess the impacts of drought on crop water demand, water availability, crop yield, and electricity requirements for irrigation. This was done by a novel spatially-explicit and integrated water-food-energy nexus model, using the spatial climatic data generated by the mesoscale MESAN and STRANG models. In this study, the model was applied to quantify the effects of drought on the Swedish irrigation sector in 2013, a typical drought year, for a specific crop. The results show that drought can severely affect the crop yield if irrigation is not applied, with a peak yield reduction of 18 t/ha, about 50 % loss as compared to the potential yield in irrigated conditions. Accordingly, the water and energy requirements for irrigation to halt the negative drought effects and maintain high yields are significant, with the peaks up to 350 mm and 700 kWh per hectare. The developed model can be used to provide near real-time guidelines for a comprehensive drought management system. The model also has significant potentials for applications in precision agriculture, especially using high-resolution satellite data.

  • 5.
    Ding, Jing
    et al.
    Sun Yat Sen Univ, Sch Engn, Guangzhou 510006, Guangdong, Peoples R China..
    Du, Lichan
    Sun Yat Sen Univ, Sch Engn, Guangzhou 510006, Guangdong, Peoples R China..
    Pan, Gechuanqi
    Sun Yat Sen Univ, Sch Engn, Guangzhou 510006, Guangdong, Peoples R China..
    Lu, Jianfeng
    Sun Yat Sen Univ, Sch Engn, Guangzhou 510006, Guangdong, Peoples R China..
    Wei, Xiaolan
    South China Univ Technol, Sch Chem & Chem Engn, Guangzhou 510640, Guangdong, Peoples R China..
    Li, Jiang
    Natl Supercomp Ctr Guangzhou, Guangzhou 510006, Guangdong, Peoples R China..
    Wang, Weilong
    Sun Yat Sen Univ, Sch Engn, Guangzhou 510006, Guangdong, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Energy, Vasteras, Sweden.
    Molecular dynamics simulations of the local structures and thermodynamic properties on molten alkali carbonate K2CO32018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 220, p. 536-544Article in journal (Refereed)
    Abstract [en]

    Molten carbonate salts have received particular attention for high-temperature thermal energy storage and heat Molecular dynamics simulation transfer applications due to desirable thermal characteristics, such as wide operating temperature range, low Molten alkali carbonates causticity and excellent thermal stability. In this study, molecular dynamics (MD) simulations were performed Local structures on molten alkali carbonate K2CO3 based on an effective pair potential model, a Born-Mayer type combined with Thermodynamic properties a Coulomb term. The radial distribution functions (RDF) and coordination number curves of the molten salt were characterized to explore the temperature dependences of macroscopic properties from microscopic view. The results suggest that the distance between K2CO3 particles is getting larger with temperature increasing, resulting in the increase of molar volume and the diminished ability of resistance to shear deformation and heat transfer by vibration between ions. Besides, it can be concluded that the structure of CO32- is inferred reasonably to be ortho-triangular pyramid from the comprehensive analysis of local structures including the angular distribution functions (ADF). Moreover, the thermodynamic properties were simulated in detail from 1200 to 1600 K including the density, thermal expansion coefficient, specific heat capacity, sheer viscosity, thermal conductivity and ion self-diffusion coefficient, which was hard to be measured from experiments under high-temperature extreme conditions, All the simulation results are in satisfactory agreement with available experimental data with high accuracy, and the minimum simulation error is as low as 1.42%.

  • 6. Ding, Y.
    et al.
    Shao, C.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. School of Business, Society and Engineering, Mälardalen University, SE-72123 Västerås, Sweden.
    Song, Y.
    Zhang, C.
    Guo, C.
    Economical flexibility options for integrating fluctuating wind energy in power systems: The case of China2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 228, p. 426-436Article in journal (Refereed)
    Abstract [en]

    The inherent stochastic nature of wind power requires additional flexibility during power system operation. Traditionally, conventional generation is the only option to provide the required flexibility. However, the provision of the flexibility from the conventional generation such as coal-fired generating units comes at the cost of significantly additional fuel consumption and carbon emissions. Fortunately, with the development of the technologies, energy storage and customer demand response would be able to compete with the conventional generation in providing the flexibility. Give that power systems should deploy the most economic resources for provision of the required operational flexibility, this paper presents a detailed analysis of the economic characteristics of these key flexibility options. The concept of “balancing cost” is proposed to represent the cost of utilizing the flexible resources to integrate the variable wind power. The key indicators are proposed respectively for the different flexible resources to measure the balancing cost. Moreover, the optimization models are developed to evaluate the indicators to find out the balancing costs when utilizing different flexible resources. The results illustrate that exploiting the potential of flexibility from demand side management is the preferred option for integrating variable wind power when the penetration level is below 10%, preventing additional fuel consumption and carbon emissions. However, it may require 8% of the customer demand to be flexible and available. Moreover, although energy storage is currently relatively expensive, it is likely to prevail over conventional generation by 2025 to 2030, when the capital cost of energy storage is projected to drop to approximately $ 400/kWh or lower. 

  • 7.
    Firmansyah, Husni
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Tan, Yuting
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Power and methanol production from biomass combined with solar and wind energy: analysis and comparison2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 576-581Conference paper (Refereed)
    Abstract [en]

    This study addresses the techno-economic analysis and comparison of systems for power and methanol production from biomass combined with solar and wind energy, from both technical and economic perspectives. Three different systems, based on Integrated Gasification Combined-Cycle (IGCC), Oxy-fuel combustion, and syngas gasification, were evaluated. The hydrogen required for methanol production comes from water electrolysis driven by solar and wind energy. In addition, the effect of location was discussed.

  • 8. Gao, X.
    et al.
    Wei, P.
    Xie, Y.
    Zhang, S.
    Niu, Z.
    Lou, Y.
    Yang, Xiaohu
    KTH.
    Jin, L.
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Experimental investigation of the cubic thermal energy storage unit with coil tubes2017In: Energy Procedia, Elsevier Ltd , 2017, p. 3709-3714Conference paper (Refereed)
    Abstract [en]

    This study presented experimental investigations on the thermal performance of a thermal energy storage (TES) unit with coil tubes. A designed test rig was built and the melting heat transfer characteristics (melting front and temperature distribution) inside the TES unit were examined. The effects of charging flow rate on the overall phase change process were examined. The results showed that natural convection accelerated the thermal energy transport in the melt phase in the top region, but weakened the heat transfer in the bottom region; this resulted in the unmelt PCM at the bottom. The melting heat transfer was overall enhanced by the increase in inlet flow rate, indicating that the full charging time can be shortened by a larger flow rate.

  • 9. Guo, S.
    et al.
    Liu, Q.
    Zhao, J.
    Jin, G.
    Wu, W.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. School of Business, Society and Engineering, Mälardalen University, 721 23 Västerås, Sweden.
    Li, H.
    Jin, H.
    Mobilized thermal energy storage: Materials, containers and economic evaluation2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 177, p. 315-329Article in journal (Refereed)
    Abstract [en]

    The transportation of thermal energy is essential for users who are located far away from heat sources. The networks connecting them achieve the goal in efficient heat delivery and reasonable cost, especially for the users with large heat demands. However, it is difficult to satisfy the heat supply of the detached or emergent users with the existing pipelines. Therefore, a promising alternative, called mobilized thermal energy storage (M-TES), was proposed to deliver the heat flexibly without the restriction of networks. In this paper, a review of studies on M-TES is conducted in terms of materials, containers and economic evaluation. The potential candidates of materials, such as sugar alcohols, hydrated salts, alkalies and zeolite are reviewed and compared based on their thermophysical properties, price, advantages and disadvantages. Various containers, including the shell-and-tube, encapsulated, direct-contact, detachable and sorptive types, are discussed from the aspects of configuration, performance and utilization. Furthermore, the studies on the economic evaluation of M-TES systems are summarized and discussed based on the analysis of the economic indicators, including initial cost, operating cost, revenue, subsidy and energy cost. Finally, the challenges and future perspectives for developing M-TES are presented.

  • 10. Hao, Y.
    et al.
    Li, W.
    Tian, Z.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. School of Business, Society and Engineering, Mälardalen University, SE 72123 Västerås, Sweden.
    Li, H.
    Jin, H.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering. School of Business, Society and Engineering, Mälardalen University, SE 72123 Västerås, Sweden.
    Integration of concentrating PVs in anaerobic digestion for biomethane production2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 231, p. 80-88Article in journal (Refereed)
    Abstract [en]

    Biogas produced from anaerobic digestion processes is considered as an important alternative to natural gas and plays a key role in the emerging market for renewable energy. Aiming at achieving a more sustainable and efficient biomethane production, this work proposed a novel energy system, which integrates concentrating photovoltaic/thermal (C-PV/T) hybrid modules into a biogas plant with chemical absorption for biogas upgrading. The investigated energy system was optimized based on the data from an existing biogas plant, and its techno-economic feasibility was evaluated. Results show that about 7% of the heat consumption and 12% of the electricity consumption of the biogas plant can be covered by solar energy, by using the produced heat in a cascade way according to the operating temperature of different processes. The production of biomethane can also be improved by 25,800 N m3/yr (or 1.7%). The net present value of the integrated system is about 2.78 MSEK and the payback period is around 10 years. In order to further improve the economic performance, it is of great importance to lower the capital cost of the C-PV/T module. 

  • 11.
    Jurasz, Jakub
    et al.
    AGH Univ Sci & Technol, Krakow, Poland.;Malardalen Univ, Vasteras, Sweden..
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    The potential of photovoltaic systems to reduce energy costs for office buildings in time-dependent and peak-load-dependent tariffs2019In: Sustainable cities and society, ISSN 2210-6707, Vol. 44, p. 871-879Article in journal (Refereed)
    Abstract [en]

    Electrical power generation across the world is facing dramatic changes for a variety of reasons related to reliability, economics and environmental concerns. Over recent years a significant increase has been observed in installed capacity of photovoltaic systems. Due to their typical seasonal and diurnal energy conversion patterns their integration into power systems creates new opportunities as well as threats. This paper intends to show how photovoltaics can contribute to reducing peak load in office buildings and thereby minimise expenditure on electricity during time- and peak-load-dependent energy prices/tariffs. An additional benefit is also provided to the national power system by reducing the need for peaking power stations. The calculations are performed for energy tariffs commonly used for commercial buildings in Poland. The simulation relies on climatic and price data for 2016. The results show significant potential for photovoltaics to reduce the peak load (from almost 60 kW to slightly over 44 kW) whilst simultaneously minimising energy costs to the building (from 1.2% up to 5.8% depending on the selected tariff). This study demonstrates the economic benefits of using PV system for reducing peak loads. A sensitivity analysis with regard to photovoltaics investment costs is carried out showing that the increasing investment costs have different impact on total energy cost depending on the considered energy tariff.

  • 12.
    Leung, Dennis Y. C.
    et al.
    Univ Hong Kong, Hong Kong, Hong Kong, Peoples R China..
    Yang, Hongxing
    Hong Kong Polytech Univ, Hong Kong, Hong Kong, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Editorial for Special Issue of the First International Conference on Applied Energy, ICAE'09, Hong Kong, January 5-7, 2009 at the journal, Applied Energy2010In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 87, no 9, p. 2861-2861Article in journal (Other academic)
  • 13. Li, H.
    et al.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Tan, Yuting
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Feasibility study about using a stand-alone wind power driven heat pump for space heating2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 228, p. 1486-1498Article in journal (Refereed)
    Abstract [en]

    Reducing energy consumption and increasing the use of renewable energy in the building sector are crucial to the mitigation of climate change. Wind power driven heat pumps have been considered as a sustainable measure to supply heat to the detached houses, especially those that even do not have access to the electricity grid. This work is to investigate the dynamic performance of a heat pump system driven by wind turbine through dynamic simulations. In order to understand the influence on the thermal comfort, which is the primary purpose of space heating, the variation of indoor temperature has been simulated in details. Results show that the wind turbine is not able to provide the electricity required by the heat pump during the heating season due to the intermittent characteristic of wind power. To improve the system performance, the influences of the capacity of wind turbine, the size of battery and the setpoint of indoor temperature were assessed. It is found that increasing the capacity of wind turbines is not necessary to reduce the loss of load probability; while on the contrary, increasing the size of battery can always reduce the loss of load probability. The setpoint temperature clearly affects the loss of load probability. A higher setpoint temperature results in a higher loss of thermal comfort probability. In addition, it is also found that the time interval used in the dynamic simulation has significant influence on the result. In order to have more accurate results, it is of great importance to choose a high resolution time step to capture the dynamic behaviour of the heat supply and its effect on the indoor temperature. 

  • 14.
    Lv, Yuexia
    et al.
    Qilu Univ Technol, Shandong Acad Sci, Sch Mech & Automot Engn, Jinan 250353, Shandong, Peoples R China.;Ningbo RK Solar Tech Ltd, Ningbo 315201, Zhejiang, Peoples R China..
    Si, Pengfei
    Tsinghua Univ, Sch Architecture, Beijing 100084, Peoples R China.;China Southwest Architecture Design & Res Inst Co, Chengdu 610041, Sichuan, Peoples R China..
    Rong, Xiangyang
    China Southwest Architecture Design & Res Inst Co, Chengdu 610041, Sichuan, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, S-72123 Västerås, Sweden..
    An Optimization Method for CCHP and River Water Source Heat Pump Combined System2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 592-597Conference paper (Refereed)
    Abstract [en]

    Combined Cooling, Heating and Power (CCHP) systems have been widely utilized in the buildings to achieve high efficiency cascade utilization of energy. Heat pump is another widely utilized technology to improve the building energy efficiency. The paper presents a hybrid system which integrates the CCHP with river water source heat pump to combine the advantages of these two technologies. A physical model with energy storage module was firstly developed for the combined system. A case study was further carried out to investigate the optimized configuration and operation performance of the combined system. Copyright

  • 15.
    Lv, Yuexia
    et al.
    Qilu Univ Technol, Shandong Acad Sci, Sch Mech & Automot Engn, Jinan, Shandong, Peoples R China.;Ningbo RK Solar Tech Ltd, Ningbo, Zhejiang, Peoples R China..
    Si, Pengfei
    Tsinghua Univ, Sch Architecture, Beijing, Peoples R China.;China Southwest Architecture Design & Res Inst Co, Chengdu, Sichuan, Peoples R China..
    Rong, Xiangyang
    China Southwest Architecture Design & Res Inst Co, Chengdu, Sichuan, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Energy, Vasteras, Sweden..
    Feng, Ya
    China Southwest Architecture Design & Res Inst Co, Chengdu, Sichuan, Peoples R China..
    Zhu, Xiaohong
    Sichuan Prov Architectural Design Inst, Chengdu, Sichuan, Peoples R China..
    Determination of optimum tilt angle and orientation for solar collectors based on effective solar heat collection2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 219, p. 11-19Article in journal (Refereed)
    Abstract [en]

    Determination of optimum tilt angle and orientation of solar collectors by maximizing the total solar radiation may overestimate the energy production benefits, because a considerable amount of solar radiation is ineffective for practical solar collectors. In this paper, the concept of effective solar heat collection is proposed to rule out the ineffective solar radiation that could not be converted to available energy. Accordingly, an optimized mathematical model is developed and used to determine the optimum tilt angle and orientation of solar collectors installed in Lhasa during the heating season. Compared with the total solar radiation based optimum results, there is a deviation of 5 degrees in the optimum orientations based on the effective solar heat collection. The case study shows that it is not advisable to adjust the optimum tilt angle on a monthly basis because there is no significance change in total solar energy gains in comparison with the case of no such adjustment during the heating season. In addition, the correction factors to achieving the maximum effective solar heat collection are given at different tilt angles and orientations to guide installation of solar collectors in practical engineering applications.

  • 16.
    Lv, Yuexia
    et al.
    Qilu Univ Technol, Shandong Acad Sci, Sch Mech & Automot Engn, Jinan 250353, Shandong, Peoples R China.;Ningbo RK Solar Tech Ltd, Ningbo 315201, Zhejiang, Peoples R China..
    Xia, Longyu
    Qilu Univ Technol, Shandong Acad Sci, Sch Mech & Automot Engn, Jinan 250353, Shandong, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, S-72123 Västerås, Sweden..
    Bi, Jinpeng
    Qilu Univ Technol, Shandong Acad Sci, Sch Mech & Automot Engn, Jinan 250353, Shandong, Peoples R China..
    Design of a Hybrid Fiber Optic Daylighting and PV Solar Lighting System2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 586-591Conference paper (Refereed)
    Abstract [en]

    Residential buildings with limited natural lighting are generally lit by fuel-based electricity which contributes to increase of CO2 concentration in the atmosphere. This paper presents the design of a hybrid fiber-optic daylighting and PV solar lighting system for household applications. The system is composed of a light collecting subsystem, a light guiding subsystem, an optical fiber light diffuser subsystem and corresponding control system. Preliminary system performance shows that, the developed system could provide comfortable and natural indoor illumination. Meanwhile, the hybrid lighting system can provide an average of 9h of electric lighting under clear sky conditions, and reduce 158.2kg of carbon dioxide emission in a year within the tested dark room of 5m(2).

  • 17.
    Lönnqvist, Tomas
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Sandberg, Thomas
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.).
    Birbue, Juan Cristóbal
    Olsson, Jesper
    Espinosa, Cecilia
    Thorin, Eva
    Grönkvist, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Gómez, María F.
    Large-scale biogas generation in Bolivia – a stepwise reconfiguration2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 180, p. 494-504Article in journal (Refereed)
    Abstract [en]

    Renewable energy is well recognized not only as resource that helps to protect the environment for future generations but also as a driver for development. Waste-to-energy systems can provide renewable energy and also improve sustainability in waste management. This article contributes a case study of stepwise reconfiguration of the waste management system in a developing country to the literature of transitions. The conditions for a systemic transition that integrates large-scale biogas generation into the waste management system have been analyzed. The method included a multi-criteria evaluation of three development steps for biogas, an economic analysis, and an institutional and organizational analysis. The results revealed economic as well as institutional and organizational barriers. Clearly, public and private sectors need to engage in sustainability. There is also a lack of pressure – mainly because of fossil fuel subsidies – that prevents a transition and creates a lock-in effect. To break the lock-in effect the municipality's institutional capacity should be strengthened. It is possible to strengthen biogas economically by integrated waste management services and sales of biofertilizer. A stepwise reconfiguration would be initiated by adopting technologies that are already established in many developed countries but are novelties in a Bolivian context – as a response to sustainability challenges related to waste management. The article focuses on the main challenges and the potential for biogas technology in Bolivia and a pathway towards a new, more sustainable system is suggested.

  • 18. Salman, C. A.
    et al.
    Naqvi, M.
    Thorin, E.
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Sweden.
    A polygeneration process for heat, power and DME production by integrating gasification with CHP plant: Modelling and simulation study2017In: Proceedings of the 9th International Conference on Applied Energy, Elsevier, 2017, Vol. 142, p. 1749-1758Conference paper (Refereed)
    Abstract [en]

    Biofuels are a good substitute for the transport sector petroleum fuels to minimize carbon footprint and greenhouse gases emissions. Di-Methyl Ether (DME) is one such alternative with properties similar to liquefied petroleum gas but with lower SOx, NOx, and particulate emissions. In this work, a polygeneration process, integrating an existing combined heat and power (CHP) plant with biomass gasification to synthesize DME, is proposed and modelled. Process integration is based on a hypothesis that the CHP plant provides the necessary heat to run the co-located gasification plant for DME synthesis and the waste heat from the gasification process is recovered and transferred to the CHP plant. The feed for gasification is taken as refuse derived fuel (RDF) instead of conventional wood derived biomass. The process integration leads to higher overall combined efficiency (up to 71%) which is greater than stand-alone efficiencies (up to 63%) but lower than stand-alone CHP plant efficiency (73.2%). The further technical evaluation shows that the efficiency of the polygeneration process is depends heavily on the gasifier capacity integrated with the existing CHP plant and also on the conversion route selected for DME synthesis i.e. recycling of unconverted syngas to the DME reactor or transferring it to the boiler of the CHP plant. The simulation results also indicate that once-through conversion yields less DME than recycling, but at the same time, once-through conversion affects the district heat and electric power production of the CHP plant lesser than by using the recycling route.

  • 19.
    Shang, Nan
    et al.
    Zhejiang Univ, Coll Elect Engn, Hangzhou 310058, Zhejiang, Peoples R China..
    Lin, You
    Zhejiang Univ, Coll Elect Engn, Hangzhou 310058, Zhejiang, Peoples R China..
    Ding, Yi
    Zhejiang Univ, Coll Elect Engn, Hangzhou 310058, Zhejiang, Peoples R China..
    Ye, Chengjin
    Zhejiang Univ, Coll Elect Engn, Hangzhou 310058, Zhejiang, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Nodal market power assessment of flexible demand resources2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 235, p. 564-577Article in journal (Refereed)
    Abstract [en]

    With the incorporation of higher shares of intermittent renewable energies (RES), more flexible resources are required in power systems to keep load balance. Under some extreme circumstances, the flexible demand resources (FDRs) may have the potential to dominate and obtain excess benefits, preventing other FDRs from participating in the electricity markets. Therefore, it is of great significance to identify the key FDR market power locations and implement some corresponding regulations. However, the relevant researches in power systems focused on the supply side, rather than the demand side. In this paper, a novel nodal market power analysis method is proposed to evaluate the potential influence of FDRs on electricity markets. Firstly, a multi-state model is established to present the multiple power system operation states including the random failures of system components. Then, the nodal market power assessment model is established under each specific state and new indices are proposed to evaluate the nodal market power of FDRs quantitatively. Furthermore, the key FDR nodes in demand side with stronger power in capturing excess revenue are identified. The 24-bus IEEE Reliability Test System is modified to demonstrate the feasibility of the proposed method. The numerical results of the proposed method are capable to display the existence of market power in demand side, and provide some valuable guidance for classification and operation of electricity markets.

  • 20.
    Tian, Zhenyu
    et al.
    Chinese Acad Sci, Inst Engn Thermophys, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Hao, Yong
    Chinese Acad Sci, Inst Engn Thermophys, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Li, Wenjia
    Chinese Acad Sci, Inst Engn Thermophys, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Sustainable Dev Soc & Technol, SE-72123 Västerås, Sweden..
    Li, Hailong
    Mälardalen Univ, Sch Sustainable Dev Soc & Technol, SE-72123 Västerås, Sweden..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Sustainable Dev Soc & Technol, SE-72123 Västerås, Sweden..
    Jin, Hongguang
    Chinese Acad Sci, Inst Engn Thermophys, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Integrating concentrating PVs in biogas upgrading2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 598-603Conference paper (Refereed)
    Abstract [en]

    Biogas produced from anaerobic digestion processes has been considered as an important alternative to natural gas and plays a key role in the emerging market for renewable energy. By removing CO2, biogas can be upgraded to vehicle fuel. Chemical absorption is one of the widely used upgrading technologies, which advantages include high purity and low loss of biomethane. However, chemical absorption usually suffers from the high consumption of thermal energy, which is required by the regeneration of the solvent. Aiming at achieving a more sustainable and efficient biomethane production, this work proposed a novel system, which integrate concentrating photovoltaic/thermal hybrid (C-PV/T) in the upgrading of biogas. Due to the ability to produce electricity and heat simultaneously and efficiently, C-PV/T can provide the demands of both the electricity and heat. By doing dynamic simulation of the energy production of C-PV/T, the technical feasibility of such a system is analyzed. Based on the design to meet the heat demand of solvent regeneration, without energy storage, the produced heat can cover 17% of the heat demand of the solvent regeneration, but 51.1% of the electricity demand; meanwhile, 140.3 MWh excess electricity can be sold for one year.

  • 21.
    Wang, Fu
    et al.
    Ningbo Univ, Fac Maritime & Transportat, Ningbo 315211, Zhejiang, Peoples R China..
    Zhu, Yingming
    Sichuan Univ, Inst New Energy & Low Carbon Technol, Chengdu 610065, Sichuan, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Performance of solar PV micro-grid systems: A comparison study2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 570-575Conference paper (Refereed)
    Abstract [en]

    Two solar PV micro-grid systems were stablished in this paper to examine and investigate their operation ability according to TOU price. Battery storage was used to adjust the operation strategies and bring in different economic benefits. Heat storage and simulation loads were also chosen to simulate the load variation. The power generation of the PV was comprehensively compared in two locations with different solar resources. The power output from PV systems in Ningbo is higher than that in Sichuan under local climate conditions, the accumulated power generation in Ningbo is 40% more than the power output in Sichuan. A preliminary operation strategy shows that the micro-grid can be continuously operated in the set mode. The battery storage has the capacity to achieve the economic optimization of the micro-grid systems.

  • 22.
    Wang, Ke
    et al.
    Beijing Inst Technol, Ctr Energy & Environm Policy Res, Beijing, Peoples R China.;Beijing Inst Technol, Sch Management & Econ, Beijing, Peoples R China.;Beijing Key Lab Energy Econ & Environm Management, Beijing, Peoples R China.;Sustainable Dev Res Inst Econ & Soc Beijing, Beijing, Peoples R China..
    Yang, Kexin
    Beijing Inst Technol, Ctr Energy & Environm Policy Res, Beijing, Peoples R China.;Beijing Inst Technol, Sch Management & Econ, Beijing, Peoples R China..
    Wei, Yi-Ming
    Beijing Inst Technol, Ctr Energy & Environm Policy Res, Beijing, Peoples R China.;Beijing Inst Technol, Sch Management & Econ, Beijing, Peoples R China.;Beijing Key Lab Energy Econ & Environm Management, Beijing, Peoples R China.;Sustainable Dev Res Inst Econ & Soc Beijing, Beijing, Peoples R China..
    Zhang, Chi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Shadow prices of direct and overall carbon emissions in China's construction industry: A parametric directional distance function-based sensitive estimation2018In: Structural Change and Economic Dynamics, ISSN 0954-349X, E-ISSN 1873-6017, Vol. 47, p. 180-193Article in journal (Refereed)
    Abstract [en]

    Construction industry, together with building materials industries supplying it, is one of China's largest emitters of CO2. Structural change in construction industry has been promoted to mitigate CO2. This paper estimates CO2 shadow price of construction industry and its supporting materials industries in China so as to help them to mitigate CO2 cost-effectively. A parametric directional distance function model, taking into account all possible directional vectors, is applied to address issues regarding arbitrary selection of direction that will affect estimation of shadow price. Results show that there is larger potential for CO2 reduction in supporting material industries than in construction industry itself and shadow price of overall CO2 is much lower than that of direct CO2. The existence of enlarging heterogeneity in shadow prices among different regions provides strong support for introducing a national carbon trading market, thereby helping construction industry and building materials industries to reduce their abatement costs.

  • 23.
    Wang, C. S.
    et al.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Sustainable Dev Soc & Technol, S-72123 Vasteras, Sweden.
    Jia, H. J.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Wu, J. Z.
    Cardiff Univ, Sch Engn, Cardiff CF24 3AA, S Glam, Wales..
    Yu, J. C.
    State Grid Tianjin Elect Power Co, Tianjin 300010, Peoples R China..
    Xu, T.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Zhang, Y.
    Malardalen Univ, Sch Sustainable Dev Soc & Technol, S-72123 Vasteras, Sweden..
    Renewable and distributed energy integration with mini/microgrids2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 237, p. 920-923Article in journal (Other academic)
  • 24.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Royal Inst Technol, Stockholm, Sweden.;Malardalen Univ, Vasteras, Sweden..
    Biofuels in Asia2009In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 86, p. S1-S10Article in journal (Other academic)
  • 25.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Dahlquist, E.
    Malardalen Univ, IGEC III, Vasteras, Sweden..
    Yang, H.
    Hong Kong Polytech Univ, Hong Kong, Hong Kong, Peoples R China..
    Guest editorial for a special issue on green energy2008In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 32, no 12, p. 1065-1065Article in journal (Other academic)
  • 26.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Dahlquist, Erik
    Editorial for Special Issue of the Third International Green Energy Conference, VisterAs, Sweden, June 18-20, 2007 at Applied Energy2009In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 86, no 2, p. 125-125Article in journal (Other academic)
  • 27.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Jin, H. G.
    Chinese Acad Sci, Inst Engn Thermophys, Beijing 100864, Peoples R China..
    Editorial for Special Issue of the IGEC-IV, the 4th International Green Energy Conference (IGEC-IV), Beijing, China, October 20-22, 2008 at the journal, Applied Energy2010In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 87, no 9, p. 2769-2769Article in journal (Other academic)
  • 28.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Wu, J.
    Yang, Y.
    Li, H.
    Wang, H.
    Wang, X.
    Editorial cleaner energy for cleaner city2018In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 152, p. 1-2Article in journal (Refereed)
  • 29.
    Yang, Xiaohu
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Institute of the Building Environment & Sustainability Technology, School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, PR China; School of Sustainable Development of Society and Technology, Mälardalen University, 721 23 Västerås, Sweden.
    Bai, Q.
    Guo, Z.
    Niu, Z.
    Yang, C.
    Jin, L.
    Lu, T. J.
    Yan, J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. School of Sustainable Development of Society and Technology, Mälardalen University, 721 23 Västerås, Sweden.
    Comparison of direct numerical simulation with volume-averaged method on composite phase change materials for thermal energy storage2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 229, p. 700-714Article in journal (Refereed)
    Abstract [en]

    Melting heat transfer in open-cell metal foams embedded in phase-change materials (PCMS) predicted by the volume-averaged method (VAM) was systematically compared with that calculated using direct numerical simulation (DNS), with particular attention placed upon the contribution of natural convection in the melt region to overall phase change heat transfer. The two-temperature model based on the assumption of local thermal non-equilibrium was employed to account for the large difference of thermal conductivity between metallic ligaments and PCM (paraffin). The Forchheimer extended Darcy model was employed to describe the additional flow resistance induced by metal foam. For the DNS, a geometric model of metal foam based on tetrakaidehedron cells was reconstructed. The DNS results demonstrated significant temperature difference between ligament surface and PCM, thus confirming the feasibility of local thermal non-equilibrium employed in VAM simulations. Relative to the DNS results, the VAM combined with the two-temperature model could satisfactorily predict transient solid-liquid interface evolution and local temperature distribution, although pore-scale features of phase change were lost. The presence of natural convection affected significantly the melting front shape, temperature distribution and full melting. The contribution of natural convection to overall phase change heat transfer should be qualitatively and quantitatively given sufficient consideration from both macroscopic (VAM) and microscopic (DNS) point of views. Besides, practical significance and economic prospective using metal foam in TES unit for WHR system to provide residential heating or hot water is discussed and analyzed.

  • 30.
    Yang, Xiaohu
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Xi'an Jiaotong University, Xi'an, China.
    Bai, Q.
    Zhang, Q.
    Hu, W.
    Jin, L.
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University (MDH), Västerås, Sweden.
    Thermal and economic analysis of charging and discharging characteristics of composite phase change materials for cold storage2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 225, p. 585-599Article in journal (Refereed)
    Abstract [en]

    This study conducted both experimental and numerical investigations on the solidification behavior in a metal foam composite phase change material (PCM) for cold storage. Volume-average-method was adopted with the help of Forchheimer-Darcy equation to model the fluid flow through porous media. Experimental measurements were performed to validate the analytical model and the numerical method, with good agreement achieved. Local thermal equilibrium and non-equilibrium states were justified numerically and experimentally. Effect of pore morphological parameters (porosity and pore density) upon the solidification features of composite PCM were investigated. For the appliance of composite PCM to cold storage, techno-economic characteristics was also assessed. Results demonstrated that the full solidification time for metal foams with a porosity of 0.93 and 0.97 can be saved 87.5% and 76.7% respectively compared with pure water. It indicated that porosity of metal foam played a dominant role in heat transfer enhancement; while pore density seemed to have little influence on phase change behavior according to the results. Local natural convection in the unsolidified phase caused a remarkable promotion of the interface evolution, and the full solidification time with natural convection considered can be saved by 14.3% compared with pure conduction for the case with the same porosity of 0.97. The economic analyses indicated that using composite PCM was profitable with a short payback period less than 2 years.

  • 31. Yang, Y.
    et al.
    Zhang, Yang
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Campana, P. E.
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Sweden.
    Peak-shaving and profit-sharing model by Aggregators in residential buildings with PV- a case study in Eskilstuna, Sweden2017In: Proceedings of the 9th International Conference on Applied Energy, Elsevier, 2017, Vol. 142, p. 3182-3193Conference paper (Refereed)
    Abstract [en]

    Nowadays, photovoltaic (PV) system combined with energy storage systems is playing increasing significant role in residential buildings in Sweden. At the same time it brings reliability problems because of the intermittency of electricity production and exceptionally distributed reservoir which is followed by the peak-valley electricity prices and power grid fluctuations. There is an increasing need for new business model and economic paradigm for a third party aggregator to bridge the gap between Power Grid and end-users. Providing the valuable electricity services at scale and breaking regulatory arbitrage, aggregators help to deliver desired levels of residents' engagements, value-added services and feasible level of unbundling of electricity market. This paper analyzes how the aggregators grab the indisputable business opportunity to interact between residents and Power Grid from the perspective of physical electricity flows and benefits share of peak-shaving. We employ a real case in Eskilstuna in Sweden to design new business model and validate using data. And the result indicates the compatibility of the aggregator service and its business model. It further sheds light on the pricing model of generated electricity by PV system, and benefits share ratio design.

  • 32.
    Yan, Jinyue
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Zhang, Zhien
    Chongqing Univ, Minist Educ China, Key Lab Low Grade Energy Utilizat Technol & Syst, Chongqing 400044, Peoples R China..
    Carbon Capture, Utilization and Storage (CCUS)2019In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 235, p. 1289-1299Article in journal (Refereed)
  • 33.
    Zhang, Chi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden..
    Yang, Jin
    China Univ Geosci, Sch Humanities & Econ Management, Beijing 100083, Peoples R China..
    Yu, Chaoqing
    Tsinghua Univ, Dept Earth Syst Sci, Beijing 100084, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, SE-72123 Vasteras, Sweden..
    Economic assessment of photovoltaic water pumping integration with dairy milk production2018In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 177, p. 750-764Article in journal (Refereed)
    Abstract [en]

    As dairy consumption grows, domestic dairy farms face challenges in reducing the cost of feeds and the production of high-quality milk for market demands. This paper aims to introduce and integrate solar energy into the milk production chain to investigate its economic performance. By collecting data on milk production processes from 11 dairy farms in China, we quantified electricity usage and costs of milk production to identify the best and worst cases. Crop yields response to the water demand and the electricity requirements of the dairy farms were considered. The study simulated scenarios of self-sufficiency at 20%, 80%, and 100%, in the identified farms by integrating a photovoltaic water pumping (PVWP) system to provide both power and water for alfalfa and other feeds' irrigation and subsequent milk production. We evaluated annual discounted cost, revenue and net profit under each scenario and case. The results showed that a dairy farm with an integrated PVWP system and self-sufficient feeds would lead to value add-ins, such as electricity saving with solar energy generation, economic cost saving of crops, and CO2 emission reduction. The analysis on return on investment (ROI) and internal rate of return (IRR) revealed that not all the self-sufficient feeds can bring positive marginal profit. Among the investigated scenarios and cases, the dairy farm marked out by the highest ROI with 3.12 and IRR with 20.4%, was the farm where the integrated PVWP system was used to reach 20% self-sufficiency (self-production of only alfalfa). The other scenarios and cases with higher levels of self-sufficiency showed lower ROIs and IRRs. This indicates that high self-production levels of feeds decrease the total profit due to high investment cost. Sensitivity analyses of crop price and operational cost were conducted for ROI with single and double factor approaches. Scale and production of feeds proportions should be carefully considered in improving the economic performance of dairy milk production.

  • 34.
    Zhang, Qi
    et al.
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China..
    Li, Hailong
    Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden.;Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Zhu, Lijing
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China..
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden.
    Lu, Huihui
    China Univ Petr, Acad Chinese Energy Strategy, Beijing 102249, Peoples R China.;Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden..
    Wallin, Fredrik
    Malardalen Univ, Sch Business Soc & Engn, Future Energy, Vasteras, Sweden..
    Sun, Qie
    Shandong Univ, Inst Thermal Sci & Technol, Jinan, Shandong, Peoples R China..
    Factors influencing the economics of public charging infrastructures for EV - A review2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 94, p. 500-509Article, review/survey (Refereed)
    Abstract [en]

    Growing concerns about energy conservation and the environmental impacts of greenhouse gas emissions over the world have promoted the development of the electric vehicles (EVs) market. However, one of the biggest barriers in the development of the EV market is the lack of the public charging infrastructure. This paper reviews the factors that can directly and indirectly influence the economics of the public charging infrastructure. The knowledge gaps, barriers and opportunities in the development of the charging infrastructure have been identified and analyzed. In order to promote the development of the public charging infrastructure, more research efforts should be paid on the impacts of psychological factors of customers and the technical development of charging infrastructures and EV batteries. The government support has been proved to play an important role, so that how the government policy can be tailored for the development of the charging infrastructure market should receive more attentions. In addition, the charging price as an endogenous factor should be considered more carefully in modelling the charging infrastructure market. New business models are also urgently needed to accelerate the future development of the public charging infrastructure.

  • 35.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Yang, Ying
    Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Lundblad, Anders
    RISE Res Inst Sweden, Div Safety & Transport Elect, SE-50462 Borås, Sweden..
    Yan, Jerry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen Univ, Sch Business Soc & Engn, SE-72123 Västerås, Sweden..
    Energy Flexibility through the Integrated Energy Supply System in Buildings: A Case Study in Sweden2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 564-569Conference paper (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energies requires more flexibility measures at the consumption side. Flexible energy prices have been placed by energy providers to promote flexibility measures from energy users. However, because of the current energy supply system in buildings, these flexible energy prices haven't been fully taken advantage of This study focuses on the integrated energy supply system in buildings. A Swedish office building is used as the case study. The integrated energy supply system is built by installing new components, including battery, heat pump and electrical heater, and hot water tank. Mixed Integer Linear Programming (MILP) problems are solved to determine the optimal component capacities and operation profiles. The results indicate that all the studied system configurations achieve lower net present cost (NPC) than the current system. It suggests that the integrated energy supply system can take advantage of the flexible energy prices and lower the overall energy cost in the building. Among the studied configurations, the combination of air source heat pump (ASHP) and electrical heater (EH) has the lowest investment cost. This combination also has the lowest NPC except in the scenario with low borehole cost.

  • 36.
    Zhang, Chi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Sustainable Business Innovation of Photovoltaic Water Pumping Systems2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The development of renewable energy technology provides an effective approach to replace fossil fuels for greenhouse gas (GHG) emission. Technological innovation and transfer are the main driving forces in promoting renewable energy usage, because of the better efficiency and economic payback under an emission reduction target. With three of the mechanisms of emission trading originating from the Kyoto Protocol, the most wildly accepted and important mechanism between developed and developing countries is the Clean Development Mechanism (CDM). The CDM has been implemented contributing the most of the trading carbon credits. In this study, by extracting and building an exclusive database of issued Chinese CDM projects, a modified multivariable logistic regression model for technology transfer’s correlation test with 11 extended indicators was investigated for the first time. Renewable energy projects were analyzed with certified emission reduction (CER) sizes, economic development, and geographic scopes.In addition, technological innovation should also be enhanced with new business developments to demonstrate and scale up technologies for better economic and environmental performances. This doctoral thesis studied photovoltaic water pumping (PVWP) technology as a technological solution for integration with the new business model for development and co-benefits. The integration of PVWP with water saving irrigation techniques and sustainable management of water resources, leads to technical innovations, economic benefits, and climate benefits. Field measurements at a pilot PVWP system in Inner Mongolia were conducted with detailed economic performance analyses. Different scenarios for PVWP systems considering variant market incentives were proposed with internal rate of return (IRR), and discounted payback period analyses to develop a new business model approach for implementing PVWP systems with multi-value propositions. The environmental externalities were successfully addressed by evaluating the CO2 emission reduction credits. The economic assessment of feasible and optimal production processes for implementing PVWP systems in dairy milk production was conducted with self-supplied energy and forage assumptions. In comparison with other financing mechanisms, discrete choice model analyses were employed with interviews and costumer behavior surveys to explore the willingness to purchase through crowd funding mechanisms in financing integrated PVWP systems.The results showed that emission reduction mechanisms, such as CDM, have promoted the renewable energy development in China with the national incentives at an entrance level. Yet, the limited sizes and lower income from CERs of renewable energy projects than other projects, required renewable energy projects to develop more advanced technological innovations and business model innovations.  The PVWP systems represent the better technical and economic solutions under a feasible innovated business model in comparison with traditional photovoltaic (PV) systems and current PV business models. The dairy farms with integrated PVWP systems and self-sufficient feeds could improve their investment performance through extra energy saving and CO2 emission reductions. The semi-structured interviews and customer surveys’ results showed that customers can tolerate high prices, and are willing to crowd-fund nutritious and secure cow milk with environmental compensation characters. The results from the PVWP technology integration in China as a specific PV application study can be further applied for the business model of innovation of renewable energy systems in other regions of the world under emission reduction targets leading to economic and environmental benefits.

    The full text will be freely available from 2019-06-01 11:01
  • 37.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Lundblad, Anders
    Wandong, Zheng
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Planning and Operation of an Integrated Energy System in a Swedish BuildingManuscript (preprint) (Other academic)
    Abstract [en]

    The increasing capacities of variable renewable energies (VRE) require more flexibility measures. The integration of energy supplies in buildings forms integrated energy systems (IES). IESs can provide flexibility and help increase the VRE penetration level. To upgrade a current building energy system into an IES, several energy conversion and storage components need to be installed. How to decide the component capacities and operate the IES were investigated separately in studies on system planning and system operation. However, a research gap exists that the system configuration from system planning is not validated by real operation conditions in system operation. Meanwhile, studies on system operation assume that the IES configuration is predetermined. This work combines system planning and system operation. The IES configuration is determined by mixed integer linear programming in system planning. Real operation conditions and forecast errors are considered in the system operation. The operation profiles are obtained through different energy management systems. The results indicate that the system configuration from system planning can meet energy demands in real operation conditions. Among different energy management systems, the combination of robust optimization and receding horizon optimization achieves the lowest yearly operation cost. Meanwhile, two scenarios that represent high and low forecast accuracies are employed. Under the high and low forecast accuracy scenarios, the yearly operation costs are about 4% and 6% higher than those obtained from system planning.

  • 38.
    Zhang, Yang
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes.
    Campana, Pietro Elia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Yang, Ying
    Stridh, Bengt
    Lundblad, Anders
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Mälardalen University, Västerås, Sweden.
    Energy flexibility from the consumer: Integrating local electricity and heat supplies in a building2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 223, p. 430-442Article in journal (Refereed)
    Abstract [en]

    The increasing penetration level of renewable energy requires more flexibility measures to be implemented in future energy systems. Integrating an energy consumer's local energy supplies connects multiple energy networks (i.e., the electrical grid, the district heating network, and gas network) in a decentralized way. Such integration enhances the flexibility of energy systems. In this work, a Swedish office building is investigated as a case study. Different components, including heat pump, electrical heater, battery and hot water storage tank are integrated into the electricity and heat supply system of the building. Special focus is placed on the flexibility that the studied building can provide to the electrical grid (i.e., the building modulates the electricity consumption in response to the grid operator's requirements). The flexibility is described by two metrics including the flexibility hours and the flexibility energy. Optimization of the component capacities and the operation profiles is carried out by using Mixed Integer Linear Programming (MILP). The results show that the system fully relies on electricity for the heat demand when not considering the flexibility requirements of the electrical grid. This suggests that district heating is economically unfavorable compared with using electricity for the heat demand in the studied case. However, when flexibility requirements are added, the system turns to the district heating network for part of the heat demand. The system provides great flexibility to the electrical grid through such integration. The flexibility hours can be over 5200 h in a year, and the flexibility energy reaches more than 15.7 MWh (36% of the yearly electricity consumption). The yearly operation cost of the system slightly increases from 62,273 to 65,178 SEK when the flexibility hours increase from 304 to 5209 h. The results revealed that flexibility can be provided from the district heating network to the electrical grid via the building.

  • 39.
    Zhu, Yingming
    et al.
    Sichuan Univ, Inst New Energy & Low Carbon Technol, Chengdu 610065, Sichuan, Peoples R China..
    Wang, Fu
    Ningbo Univ, Fac Maritime & Transportat, Ningbo 315211, Zhejiang, Peoples R China.;Ningbo RX New Mat Tech Co Ltd, Ningbo 315200, Zhejiang, Peoples R China..
    Yan, Jinyue
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Energy Processes. Sichuan Univ, Inst New Energy & Low Carbon Technol, Chengdu 610065, Sichuan, Peoples R China..
    The Potential of Distributed Energy Resources in Building Sustainable Campus: The Case of Sichuan University2018In: RENEWABLE ENERGY INTEGRATION WITH MINI/MICROGRID / [ed] Yan, J Wang, C Yu, J Jia, H Wu, J Xu, T Zhang, Y, ELSEVIER SCIENCE BV , 2018, p. 582-585Conference paper (Refereed)
    Abstract [en]

    Distributed energy resources systems are decentralized, modular and more flexible technologies. These systems can comprise multiple generation and storage components. Sichuan University (SCU) has joined Global Urban Development program, and takes part in Sustainability Tracking, Assessment & Rating System, aims at a sustainable campus. So we investigated the potential of distributed energy resources, e.g. solar power, that can be used in SCU. Firstly, we build 4 micro-grids with a total 156 Kw PV capacities to collect the power generation data. The total roof area of SCU Jiangan campus is 165701 m(2), and the estimated installed capacity is 8.3MW-11.6MW. Based on this data, 33% similar to 46% power cost can be covered by PV power generation.

1 - 39 of 39
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