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  • 1.
    Abas, N.
    et al.
    University of Gujrat, Hafiz Hayat Campus, Gujrat, Pakistan.
    Kalair, A. R.
    COMSATS University Islamabad, Islamabad, Pakistan.
    Seyedmahmoudian, M.
    Swinburne University, Australia.
    Naqvi, M.
    Karlstad University.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Khan, N.
    COMSATS University Islamabad, Islamabad, Pakistan.
    Dynamic simulation of solar water heating system using supercritical CO2 as mediating fluid under sub-zero temperature conditions2019Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 161, artikel-id 114152Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    CO2 is becoming increasingly important as a mediating fluid, and simulation studies are indispensable for corresponding developments. In this study, a simulation-based performance investigation of a solar water heating system using CO2 as a mediating fluid under sub-zero temperature condition is performed using the TRNSYS® software. The maximum performance is achieved at a solar savings fraction of 0.83 during July. The as lowest solar savingss fraction of 0.41 is obtained during December. The annual heat production of the proposed system under Fargo climate is estimated to be about 2545 kWh. An evacuated glass tube solar collector is designed, fabricated and tested for various climate conditions. Moreover, a detailed comparison of the system's performance at sub/supercritical and supercritical pressures shows that the annual heat transfer efficiency of the modeled system is 10% higher at supercritical pressure than at sub/supercritical pressures. This result can be attributd to the strong convection flow of CO2 caused by density inhomogeneities, especially in the near critical region. This condition resuls in high heat transfer rates.

  • 2.
    Bai, Q.
    et al.
    School of Human Settlements and Civil Engineering, Xi'An Jiaotong University, Xi'an, China.
    Guo, Z.
    School of Human Settlements and Civil Engineering, Xi'An Jiaotong University, Xi'an, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yang, Xiaohu
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Jin, L.
    School of Human Settlements and Civil Engineering, Xi'An Jiaotong University, Xi'an, China.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology (KTH), Stockholm, Sweden.
    Experimental investigation on the solidification behavior of phase change materials in open-cell metal foams2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 3703-3708Artikel i tidskrift (Refereegranskat)
    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. 

  • 3.
    Benavente, F.
    et al.
    Department of Chemical Engineering, Applied Electrochemistry, KTH Royal Institute of Technology, Stockholm, Sweden.
    Lundblad, A.
    Division of Safety and Transport/Electronics, RISE, Research Institutes of Sweden, Borås, Sweden.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Department of Chemical Engineering, Applied Electrochemistry, KTH Royal Institute of Technology, Stockholm, Sweden.
    Zhang, Y.
    Department of Chemical Engineering, Applied Electrochemistry, KTH Royal Institute of Technology, Stockholm, Sweden.
    Cabrera, S.
    Instituto de Investigaciones Químicas, Carrera de Ciencias Químicas, UMSA Universidad Mayor de San Andrés, Bolivia.
    Lindbergh, G.
    Department of Chemical Engineering, Applied Electrochemistry, KTH Royal Institute of Technology, Stockholm, Sweden.
    Photovoltaic/battery system sizing for rural electrification in Bolivia: Considering the suppressed demand effect2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 235, s. 519-528Artikel i tidskrift (Refereegranskat)
    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.

  • 4.
    Benavente-Araoz, F.
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Lundblad, A.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, Y.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Cabrera, S.
    UMSA Universidad Mayor de San Andrés, Bolivia.
    Lindbergh, G.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Loss-of-load probability analysis for optimization of small off-grid PV-battery systems in Bolivia2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 3715-3720Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study evaluates the use of energy storage technologies coupled to renewable energy sources in rural electrification as a way to address the energy access challenge. Characteristic energy demanding applications will differently affect the operating conditions for off-grid renewable energy systems. This paper discusses and evaluates simulated photovoltaic power output and battery state of charge profiles, using estimated climate data and electricity load profiles for the Altiplanic highland location of Patacamaya in Bolivia to determine the loss of load probability as optimization parameter. Simulations are performed for three rural applications: household, school, and health center. Increase in battery size prevents risk of electricity blackouts while increasing the energy reliability of the system. Moreover, increase of PV module size leads to energy excess conditions for the system reducing its efficiency. The results obtained here are important for the application of off-grid PV-battery systems design in rural electrification projects, as an efficient and reliable source of electricity.

  • 5.
    Bian, Caiyun
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Academy of Chinese Energy Strategy, China University of Petroleum-Beijing, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lin, L.
    Academy of Chinese Energy Strategy, China University of Petroleum-Beijing, Beijing, 102249, China.
    Yu, Z.
    Department of Energy and Petroleum EngineeringUniversity of Stavanger, Norway.
    Finding the optimal location for public charging stations - A GIS-based MILP approach2019Ingår i: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, s. 6582-6588Konferensbidrag (Refereegranskat)
    Abstract [en]

    Electric Vehicles (EVs) have achieved a significant development because of the continuous technology revolution and policy supports in recent years, which leads to a larger demand of charging stations. Strategies about how to find the optimal location for charging facilities are urgently needed in order to further assist the development of EVs. This paper focus on the return of investments on EV charging stations and proposes a Mixed Integer Linear Programming (MILP) model based on Geographic Information System (GIS) to identify the optimal location of charging stations in cities. Traffic flow data and land-use classifications are used as important inputs, and six important constraints are included in the MILP model with the objective function of maximizing the total profits of new charging stations. The effectiveness of the proposed method is then demonstrated by implementing a case study in Västerås, Sweden.

  • 6.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    PV water pumping systems for agricultural applications2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Grassland and farmland degradation is considered as one of the worst environmental and economic threats for China. The degradation process negatively affects food and water security, economy, society and climate changes.

    Photovoltaic water pumping (PVWP) technology for irrigation is an innovative and sustainable solution to curb the grassland degradation. At the same time it can promote the conservation of farmland, especially in remote areas of China. The combination of PVWP technology with water saving irrigation techniques and sustainable management of the groundwater resources can lead to several benefits. These include enhancing grassland productivity, halting wind and rainfall erosion, providing higher incomes and better living conditions for farmers.   

    This doctoral thesis aims to bridge the current knowledge gaps, optimize system implementation and prevent system failures. This work represents thus a step forward to solve the current and future nexus between energy, water and food security in China, using PVWP technology for irrigation.

    Models for the dynamic simulations of PVWP systems, irrigation water requirements (IWR) and crop response to water have been presented and integrated. Field measurements at a pilot PVWP system in Inner Mongolia have been conducted to analyse the reliability of the models adopted. A revision of the traditional design approaches and a new optimization procedure based on a genetic algorithm (GA) have been proposed to guarantee the match between IWR and water supply, to minimize the system failures and to maximize crop productivity and thus the PVWP system profitability and effectiveness.

    Several economic analyses have been conducted to establish the most cost effective solution for irrigation and to evaluate the project profitability. The possible benefits generated by the PVWP system implementation have been highlighted, as well as the effects of the most sensitive parameters, such as forage price and incentives. The results show that PVWP system represents the best technical and economic solution to provide water for irrigation in the remote areas compared to other traditional water pumping technologies. The environmental benefits have been also addressed, evaluating the CO2 emissions saving achievable from the PVWP system operation. The assessment of the feasible and optimal areas for implementing PVWP systems in China has been conducted using spatial analysis and an optimization tool for the entire supply chain of forage production. The results show that the potentials of PVWP systems in China are large. Nevertheless, the feasible and optimal locations are extremely sensitive to several environmental and economic para­meters such as forage IWR, groundwater depth, and CO2 credits that need to be carefully taken into account in the planning process.   

    Although this doctoral thesis has used China as case study, PVWP technology can be applied for irrigation purposes all over the world both for off- and on-grid applications leading to several economic and environmental benefits.

    Ladda ner fulltext (pdf)
    fulltext
  • 7.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    PV water pumping systems for grassland and farmland conservation2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Grassland degradation is considered as one of the worst environmental and economic problems in China because of the negative impacts on water and food security. The application of the photovoltaic water pumping (PVWP) technology for irrigation is an innovative and sustainable solution to curb the progress of grassland desertification and to promote the conservation of farmland in remote areas. The combination of PVWP with water saving irrigation techniques and the sustainable management of the water resources enhances the grass productivity enabling to halt wind and rainfall erosion and to provide higher incomes and better living conditions for farmers. PVWP systems have been used for more than 40 years especially for drinking purposes, livestock watering and irrigation in small-medium size applications. Nevertheless, several knowledge gaps still exist and system failures still occur, which are mainly bounded to the system design procedure and optimization. The technical and economic feasibilities related to the system implementation, especially effectiveness and profitability, need to be addressed. Moreover, irrigation in remote areas constrained by availability of water resources has to be investigated for a better understanding of PVWP system integration with the environment and for optimization purposes. This thesis is to bridge the current knowledge gaps, optimize system implementation and prevent system failures 

     

    Validation of the models adopted and optimization of the system on the basis of solar energy resources and exploitable groundwater has been performed for a pilot PVWP system in Inner Mongolia. The match between the water supplied through the pumping system and the grass water demand has been studied, and the effects of pumping on the available resources and the crop productivity have been evaluated. The economic analyses have also been conducted in order to establish the most cost effective solution to provide water for irrigation and to evaluate the project profitability. In addition, the CO2 emission reductions by using PV technology have been assessed as well.

     

    It was found that the proper designed PVWP system represents the best technical and economic solution to provide water for irrigation in the remote areas compared to other water pumping technologies, such as diesel water pumping and wind power water pumping due to the high positive net present values and short payback periods.

    Ladda ner fulltext (pdf)
    fulltext
  • 8.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Cheng, Fu
    Ericson, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Andersson, Sandra
    Landelius, Tomas
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Modelling the diffuse component of solar radiation using artificial intelligence techniques2018Konferensbidrag (Refereegranskat)
  • 9.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Cioccolanti, Luca
    François, B.
    Jurasz, J.
    Zhang, Yang
    Stridh, Bengt
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    A Multi-Country Economic Analysis Of Lithium-Ion Batteries For Peak Shaving And Price Arbitrage In Commercial Buildings2018Konferensbidrag (Refereegranskat)
  • 10.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Daianova, L.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Desideri, U.
    Bioethanol Production from Lignocellulosic Biomass, Evaluation of the Potential Bioethanol Production in Three Swedish Regions2009Konferensbidrag (Refereegranskat)
  • 11.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Landelius, T.
    Swedish Meteorological and Hydrological Institute, Norrköping, Sweden.
    Andersson, S.
    Swedish Meteorological and Hydrological Institute, Norrköping, Sweden.
    Lundström, Lukas
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nordlander, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    He, T.
    Wuhan University, Wuhan, China.
    Zhang, J.
    Uppsala University, Uppsala, Sweden.
    Stridh, Bengt
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    A gridded optimization model for photovoltaic applications2020Ingår i: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 202, s. 465-484Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study aims to develop a gridded optimization model for studying photovoltaic applications in Nordic countries. The model uses the spatial and temporal data generated by the mesoscale models STRÅNG and MESAN developed by the Swedish Meteorological and Hydrological Institute. The model is developed based on the comparison between five irradiance databases, three decomposition models, two transposition models, and two photovoltaic models. Several techno-economic and environmental aspects of photovoltaic systems and photovoltaic systems integrated with batteries are investigated from a spatial perspective. CM SAF SARAH-2, Engerer2, and Perez1990 have shown the best performances among the irradiance databases, and decomposition and transposition models, respectively. STRÅNG resulted in the second-best irradiance database to be used in Sweden for photovoltaic applications when comparing hourly global horizontal irradiance with weather station data. The developed model can be employed for carrying out further detailed gridded techno-economic assessments of photovoltaic applications and energy systems in general in Nordic countries. The model structure is generic and can be applied to every gridded climatological database worldwide.

  • 12.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Leduc, S.
    IIASA, Laxenburg, Austria.
    Kim, M
    Korea Univ., Seul, Korea.
    Liu, J.
    Beijing Forestry Univ, Peoples R China.
    Kraxner, F.
    IIASA, Laxenburg, Austria.
    McCallum, I.
    IIASA, Laxenburg, Austria.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH Royal Inst Technol, Stockholm.
    Optimal grassland locations for sustainable photovoltaic water pumping systems in China2015Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, s. 301-307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Grassland is of strategic importance for food security of China because of the high number of livestock raised in those areas. Grassland degradation due to climate change and overgrazing is thus regarded as severe environmental and economic threat for a sustainable future development of China. Photovoltaic water pumping (PVWP) systems for irrigation can play an important role for the conservation of grassland areas, halting degradation, improving its productivity and farmers' income and living conditions. The aim of this paper is to identify the technically suitable grassland areas for the implementation of PVWP systems by assessing spatial data on land cover and slope, precipitation, potential evapotranspiration and water stress index. Furthermore, the optimal locations for installing PVWP systems have been assessed using a spatially explicit renewable energy systems optimization model based on the minimization of the cost of the whole supply chain. The results indicate that the PVWP-supported grassland areas show high potential in terms of improving forage productivity to contribute to supplying the local demand. Nevertheless, the optimal areas are highly sensitive to several environmental and economic parameters such as ground water depth, forage water requirements, forage price and CO2 emission costs. These parameters need to be carefully considered in the planning process to meet the forage yield potentials.

  • 13.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Leduc, S.
    Int Inst Appl Syst Anal, Laxenburg, Austria..
    Kim, M.
    Korea Univ, South Korea..
    Olsson, A.
    KTH Royal Inst Technol, Stockholm, Sweden..
    Zhang, J.
    Univ Maryland, USA..
    Liu, J.
    Int Inst Appl Syst Anal, Laxenburg, Austria.; South Univ Sci & Technol China, Sch Environm Sci & Engn, Shenzhen 518055, Peoples R China.;Beijing Forestry Univ, Sch Nat Conservat, Peoples R China..
    Kraxner, F.
    Int Inst Appl Syst Anal, Laxenburg, Austria..
    McCallum, I.
    Int Inst Appl Syst Anal, Laxenburg, Austria..
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Suitable and optimal locations for implementing photovoltaic water pumping systems for grassland irrigation in China2017Ingår i: APPLIED ENERGY, ISSN 0306-2619, Vol. 185, s. 1879-1889Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Grassland plays a key role for the food security of China because of the large number of livestock raised in those areas. Thus, grassland degradation due to climate change and overgrazing is considered as one of the most severe environmental and economic threat for the future sustainable development of China. Photovoltaic water pumping systems for irrigation can play a fundamental role for the conservation of grassland areas. This paper investigates the geospatial distribution of the technically suitable grassland locations for the implementation of photovoltaic water pumping systems. The technically suitable grassland areas were taken as starting point to assess the optimal locations. The assessment of the optimal locations was conducted using a spatially explicit optimization model of renewable energy systems based on the cost minimization of the whole forage supply chain. The results indicate that the photovoltaic water pumping systems provide high potential for improving forage productivity, contributing to meet the local demand. The optimal areas are highly sensitive to several environmental and economic parameters such as increased forage potential yield, forage management costs, forage water requirements, ground water depth, forage price and CO2 price. Most of the optimal areas are selected when the market forage price ranges from 300 to 500 $/tonne DM, indicating that the forage produced using PVWP technology for irrigation is already competitive compared to the imported forage.

  • 14.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hao, Yong
    Jin, H.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Optimal C-PV/T system integrated in biomethane production2018Konferensbidrag (Refereegranskat)
  • 15.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Li, Hailong
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Dynamic modelling of a pv pumping system with special consideration on water demandIngår i: Proceedings of ICAE2012 / [ed] Applied EnergyKonferensbidrag (Övrigt vetenskapligt)
    Ladda ner fulltext (pdf)
    Dynamic modelling of a pv pumping system with special consideration on water demand
  • 16.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dynamic modelling of a PV pumping system with special consideration on water demand2013Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 112, s. 635-645Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The exploitation of solar energy in remote areas through photovoltaic (PV) systems is an attractive solution for water pumping for irrigation systems. The design of a photovoltaic water pumping system (PVWPS) strictly depends on the estimation of the crop water requirements and land use since the water demand varies during the watering season and the solar irradiation changes time by time. It is of significance to conduct dynamic simulations in order to achieve the successful and optimal design. The aim of this paper is to develop a dynamic modelling tool for the design of a of photovoltaic water pumping system by combining the models of the water demand, the solar PV power and the pumping system, which can be used to validate the design procedure in terms of matching between water demand and water supply. Both alternate current (AC) and direct current (DC) pumps and both fixed and two-axis tracking PV array were analyzed. The tool has been applied in a case study. Results show that it has the ability to do rapid design and optimization of PV water pumping system by reducing the power peak and selecting the proper devices from both technical and economic viewpoints. Among the different alternatives considered in this study, the AC fixed system represented the best cost effective solution.

  • 17.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH Royal Inst Technol, Stockholm, Sweden.
    Techno-economic feasibility of the irrigation system for the grassland and farmland conservation in China: photovoltaic vs. wind power water pumping2015Ingår i: Energy Conversion and Management, ISSN 0196-8904, Vol. 103, nr 6, s. 311-320Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Photovoltaic water pumping (PVWP) and wind power water pumping (WPWP) systems for irrigation represent innovative solutions for the restoration of degraded grassland and the conservation of farmland in remote areas of China. The present work systematically compares the technical and economic suitability of such systems, providing a general approach for the design and selection of the suitable technology for irrigation purposes. The model calculates the PVWP and WPWP systems sizes based on irrigation water requirement (IWR), solar irradiation and wind speed. Based on the lowest PVWP and WPWP systems components costs, WPWP systems can compete with PVWP systems only at high wind speed and low solar irradiation values. Nevertheless, taking into account the average specific costs both for PVWP and WPWP systems, it can be concluded that the most cost-effective solution for irrigation is site specific. According to the dynamic simulations, it has also been found that the PVWP systems present better performances in terms of matching between IWR and water supply compared to the WPWP systems. The mismatch between IWR and pumped water resulted in a reduction of crop yield. Therefore, the dynamic simulations of the crop yield are essential for economic assessment and technology selection.

  • 18.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zaccaria, Valentina
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, Yang
    Stridh, Bengt
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Flexibility Services Provided by Building Thermal Inertia2018Konferensbidrag (Refereegranskat)
  • 19.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, J.
    Institute of Water Resources and Hydropower Research, Beijing, China .
    Liu, J.
    Institute of Water Resources and Hydropower Research, Beijing, China .
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Economic optimization of photovoltaic water pumping systems for irrigation2015Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 95, s. 32-41Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Photovoltaic water pumping technology is considered as a sustainable and economical solution to provide water for irrigation, which can halt grassland degradation and promote farmland conservation in China. The appropriate design and operation significantly depend on the available solar irradiation, crop water demand, water resources and the corresponding benefit from the crop sale. In this work, a novel optimization procedure is proposed, which takes into consideration not only the availability of groundwater resources and the effect of water supply on crop yield, but also the investment cost of photovoltaic water pumping system and the revenue from crop sale. A simulation model, which combines the dynamics of photovoltaic water pumping system, groundwater level, water supply, crop water demand and crop yield, is employed during the optimization. To prove the effectiveness of the new optimization approach, it has been applied to an existing photovoltaic water pumping system. Results show that the optimal configuration can guarantee continuous operations and lead to a substantial reduction of photovoltaic array size and consequently of the investment capital cost and the payback period. Sensitivity studies have been conducted to investigate the impacts of the prices of photovoltaic modules and forage on the optimization. Results show that the water resource is a determinant factor.

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  • 20.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Olsson, A.
    KTH Royal Institute of Technology, Stockholm.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    An economic analysis of photovoltaic water pumping irrigation systems2016Ingår i: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 13, nr 8, s. 831-839Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    ABSTRACT: Irrigation using the photovoltaic water pumping (PVWP) systems represents a sustainable and attractive solution, which can combat Chinese grassland desertification and promote a sustainable development of the agricultural sector. This paper investigates the economics of PVWP systems taking into consideration the effects of the key components on the initial capital cost (ICC), life cycle cost (LCC), and revenues. Sensitivity analyses are conducted regarding the crop yield and price, cost of photovoltaic modules, and system components included in the ICC. Results show that the cost of the PVWP system is the most sensitive parameter affecting the ICC under the assumptions made, especially the cost of the PV modules; whereas, the crop production and price affect the net present value (NPV) and payback period (PBP) clearly. The PVWP has surplus power output when the crop water demand is low or it is non-irrigation season. The potential benefit from selling the surplus electricity is also discussed. In addition, the indirect benefits of carbon sequestration and CO2 emission reduction by applying PVWP systems are addressed in this paper.

  • 21.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Olsson, Alexander
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Economic analysis of photovoltaic water pumping irrigation systems2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Irrigation through photovoltaic water pumping (PVWP) system represents one of sustainable and attractivesolutions regarding the problems related to the Chinese grassland desertification. This paper is to investigatethe economics of PVWP systems taking in consideration of the key parameters affecting the sizing, and furtherthe initial capital cost (ICC), the life cycle cost (LCC) and revenues. In particular photovoltaic (PV) modules cost,availability of the well and of the irrigation system, designing water-head, irrigated area and related waterdemand, fuel price and grass production are investigated for the sensitivity analysis. The possibility ofcombining water pumping with electricity production for maximizing benefits is also discussed. Both PVWP anddiesel water pumping (DWP) systems are compared in terms of ICC and LCC. LCC, sensitivity, break-even point(BEP), net present value (NPV) and payback period (PBP) analyses are used to compare and evaluate theeconomic feasibility of the different alternatives investigated. The results show that the availability of the welland the depth of the ground water resources are the most sensitive parameters affecting the initial capitalcosts whereas the grass production and incentives affect mainly the NPV and PBP. The co-benefits for carbonmitigation and carbon credit trading through implementing photovoltaic water pumping system for the Chinesegrassland are also addressed in this paper.

  • 22.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Olsson, Alexander
    Zhang, Chi
    Berretta, Sara
    Hailong, Li
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    On-grid photovoltaic water pumping systems for agricultural purposes: Comparison of the potential benefits under three different incentive schemes2014Konferensbidrag (Övrigt vetenskapligt)
  • 23.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Varini, Maria
    Chiche, Ariel
    Zhang, Y.
    Zhang, Chi
    Lundblad, Anders
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    High Share Renewable Islands Through Synergies Between Energy Networks2018Konferensbidrag (Refereegranskat)
  • 24.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology, Stockholm, Sweden.
    Wästhage, Louise
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nookuea, Worrada
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Tan, Y.
    Royal Institute of Technology, Stockholm, Sweden.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology, Stockholm, Sweden.
    Optimization and assessment of floating and floating-tracking PV systems integrated in on- and off-grid hybrid energy systems2019Ingår i: Solar Energy, ISSN 0038-092X, E-ISSN 1471-1257, Vol. 177, s. 782-795Artikel i tidskrift (Refereegranskat)
    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.

  • 25.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yang, Z.
    KTH Royal Institute of Technology, Sweden.
    Anders, Lundblad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH Royal Institute of Technology, Sweden.
    An Open-source Platform for Simulation and Optimization of Clean Energy Technologies2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 946-952Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper is to describe an open-source code for optimization of clean energy technologies. The model covers the whole chain of energy systems including mainly 6 areas: renewable energies, clean energy conversion technologies, mitigation technologies, intelligent energy uses, energy storage, and sustainability. Originally developed for optimization of renewable water pumping systems for irrigation, the open-source model is written in Matlab® and performs simulation, optimization, and design of hybrid power systems for off-grid and on-grid applications. The model uses genetic algorithm (GA) as optimization technique to find the best mix among power sources, storage systems, and back-up sources to minimize life cycle cost, and renewable power system reliability. 

  • 26.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH Royal Inst Technol, Dept Chem Engn, Stockholm, Sweden..
    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, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. 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 nexus2018Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 197, s. 1382-1393Artikel i tidskrift (Refereegranskat)
    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.

  • 27.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, Jie
    Yao, Tian
    Andersson, Sandra
    Landelius, Tomas
    Melton, Forrest
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Modelling the water-food-energy nexus during agricultural drought in Sweden2018Konferensbidrag (Refereegranskat)
  • 28.
    Campana, Pietro Elia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhu, Y.
    Chengdu University, China.
    Brugiati, Elena
    Università Degli Studi di Perugia, Italy.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    PV water pumping for irrigation equipped with a novel control system for water savings2014Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 61, s. 949-952Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Typically, PV water pumping (PVWP) systems for irrigation are normally designed based on the worst conditions, such as high water demand and low solar irradiation. Therefore, the installed PVWP systems become oversized in most of time. Since the conventional control systems don't optimize the water supply, the water losses are increased. To remedy the problems related to the operation of the oversized systems, a novel control system is proposed. The control unit interacts between water demand and water supply in order to pump only the amount required by crops. Moreover, the novel control system substitutes the conventional protection approach with a method based on the ground water resources availability and response. The novel control system represents an innovative solution for water savings in PV watering applications.

  • 29.
    Chen, B.
    et al.
    Beijing Normal University, China.
    Xiong, R.
    Beijing Institute of Technology, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Sun, Q.
    Shandong University, Jinan, China.
    Yang, J.
    China University of Geosciences, Beijing, China.
    Pathways for sustainable energy transition2019Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 228, s. 1564-1571Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Energy transitions are ongoing processes all over the world. While sustainable solutions are envisioned for the future, many societies are still under high-carbon and high-pollution energy regime borne by fossil fuels. How to design pathways towards sustainable energy transition has attracted worldwide concerns. Understanding the possible transition pathways of the energy system requires the integration of new energy technologies, environmental sciences, economics and management. This Special Issue of Journal of Cleaner Production targets to collect the latest research results on sustainable energy systems, discover innovative avenues and inspiring models and share knowledge on energy system modelling and management. In this paper, we identify 4 themes on sustainable energy transition pathways including: (1)Sustainable energy economics and management; (2)Renewable energy generation and consumption; (3)Environmental impacts of energy systems; and (4)Electric vehicle and energy storage. Theories, technologies, innovative models, and successful experiences are discussed accordingly. It is suggested that creative, robust and audacious strategies in governance, management and education are needed to boost sustainable energy transition across various scales and sectors.

  • 30.
    Chen, Chang
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, Key Laboratory China of Refrigeration Technology of Tianjin, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, Key Laboratory China of Refrigeration Technology of Tianjin, 300134, China.
    Li, X.
    Tianjin University of Commerce, Key Laboratory China of Refrigeration Technology of Tianjin, China.
    Wang, Y.
    Tianjin University of Commerce, Key Laboratory China of Refrigeration Technology of Tianjin, China.
    Zhu, K.
    Tianjin University of Commerce, Key Laboratory China of Refrigeration Technology of Tianjin, China.
    Feasibility of using thermal inertia to shift the peak energy demand of buildings2018Ingår i: International Heat Transfer Conference, Begell House Inc. , 2018, s. 4419-4424Konferensbidrag (Refereegranskat)
    Abstract [en]

    Peak load introduces stress to the grid as supplied electricity is inadequate during peak demand period. In order to relieve the stress of grid and ensure the electricity supply, peak load shifting is an effective option. Buildings are consuming a huge amount of energy for space heating, ventilation and cooling. Using building thermal inertia to shift peak load has attracted more and more attention. By using thermal inertia, heat supplied during off-peak periods can be stored in the construction materials, and used in peak demand hours. However, peak shaving shall not sacrifice the indoor thermal comfort. The objective of this work is to investigate the impact of demand shifting by using thermal inertia on the indoor temperature. In order to understand how the demand shifting impacts the thermal comfort. A CFD model is developed to simulate an office room in winter time. Three cases that represent different shifting strategies are studied. According the results, when increasing the heating temperature, using thermal inertia of buildings can shift peak load, guarantee indoor thermal comfort and save energy. © 2018 International Heat Transfer Conference. All rights reserved.

  • 31.
    Chen, S.
    et al.
    Academy of Chinese Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Li, M.
    Academy of Chinese Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Zhang, Q.
    Academy of Chinese Energy Strategy, China University of Petroleum-Beijing, Changping, Beijing, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Study on the Oil Import/Export Quota Allocation Mechanism in China by Using a Dynamic Game-Theoretic Model2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 3856-3861Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    With the rapid progress of oil market reform in China, independent refineries (small companies) get more and more oil import/export quotas, which will bring big impacts on the whole market and society. However, whether the impacts are positive or negative is highly dependent on the quota allocation mechanism and prices in global/domestic market markets. Therefore, in the present study, considering the game relationships among the six agents including state-owned companies, independent refineries, domestic and foreign oil product consumers, and domestic and foreign crude oil producers, in order to calculate the detailed impacts, a game-theoretic analysis model was developed. The impacts of different quota mechanism are analyzed and compared, and the optimal quota mechanism in different price scenarios is obtained based on the developed model. 

  • 32.
    Chen, S.
    et al.
    State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China.
    Liu, J.
    State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China.
    Wang, H.
    State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China.
    Yan, J.
    School of Chemical Science, Royal Institute of Technology, Stockholm, Sweden.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, J.
    State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing, China.
    Interaction relationship between urban domestic energy consumption and water use - A case study of Beijing and Shanghai2016Ingår i: Water Policy, ISSN 1366-7017, E-ISSN 1996-9759, Vol. 18, nr 3, s. 670-684Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Energy consumption and water use are inextricably linked. Combining research on energy consumption and water use in an urban context provides a scientific basis for the integrated planning of energy and water supply systems. Domestic energy and water are among the most consumed resources in urban environments. Furthermore, domestic resources represent an increasing proportion of the total resources consumed. This paper explores four key indicators of urban energy consumption (UEC) and water use in Beijing and Shanghai for the period of 2000 to 2011. Using correlation analysis, this study establishes the intrinsic relationship between UEC and water use. It also offers an analysis of the consumption trends of these two resources as well as their interactive relationship. The results show that urban domestic energy consumption (UDEC) and water use have a significant linear correlation: UDEC is positively correlated with water use, and the correlation coefficients of Beijing and Shanghai are 0.81 and 0.97, respectively. In Beijing, urban domestic energy and water use per capita are negatively correlated, with the high correlation coefficient of 0.93. In Shanghai, urban domestic energy and water use per capita are positively correlated, with the correlation coefficient of 0.90.

  • 33.
    Chen, S.
    et al.
    China University of Petroleum-Beijing, China.
    Zhang, Q.
    China University of Petroleum-Beijing, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, China.
    Mclellan, B.
    Kyoto University, Japan.
    Zhang, T.
    China University of Petroleum-Beijing, China.
    Tan, Z.
    Investment decision on shallow geothermal heating & cooling based on compound options model: A case study of China2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 254, artikel-id 113655Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Developing shallow geothermal energy is expected to play an important role to supply affordable, clean and reliable heating by many countries in the world. However, the development is mainly hindered by the high upfront investment costs and various risks involved in the exploration, construction and operation phases. The present study proposed a compound options model to explore the optimal investment timing and value based on the consideration of both investment and operational flexibilities. The Least Square Monte Carlo and Markov Chain Monte Carlo methods were employed in the model to find the solutions. A case study was carried out for China, and five scenarios were simulated to understand the effects of different policies including subsidy, carbon trading mechanism, preferential taxation and preferential electricity price. The obtained results show that, (i) the incentive policies are essential for the development of shallow geothermal energy, which can attract more investment before 2030; (ii) the government is suggested to carry out a preferential electricity price for shallow geothermal development, rather than increase the subsidy; (iii) the application of compound options method increases the investment value in all five scenarios, but its impact on investment timing varies.

  • 34.
    Dai, B.
    et al.
    Tianjin University of Commerce, Tianjin, China.
    Liu, S.
    Tianjin University of Commerce, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin University of Commerce, Tianjin, China.
    Sun, Z.
    Tianjin University of Commerce, Tianjin, China.
    Song, M.
    The University of Tokyo, Chiba, Japan.
    Yang, Q.
    Tianjin University of Commerce, Tianjin, China.
    Ma, Yitai
    The University of Tokyo, Chiba, Japan.
    Energetic performance of transcritical CO2 refrigeration cycles with mechanical subcooling using zeotropic mixture as refrigerant2018Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 150, s. 205-221Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Transcritical CO2 refrigeration cycle integrated with mechanical subcooling (MS) cycle operating with zeotropic mixture is proposed in this study, based on the concept of Lorenz cycle. An energetic model is developed and analyses are conducted in detail. A maximum overall coefficient of performance (COP) is achieved at the optimum discharge pressure and optimum subcooling degree. The maximum overall COP, optimum subcooling degree and discharge pressure are closely related to the temperature glide of the mixtures. The energy efficiency of the transcritical CO2 refrigeration cycle can be efficiently improved, and the high pressure can be reduced when mixtures with proper temperature glide are used as MS cycle refrigerant. Compared with pure R32, the overall COP is enhanced by 4.91%, and the discharge pressure decreases by 0.11 MPa at evaporation temperature of −5 °C and ambient temperature of 35 °C when R32/R1234ze(Z) (55/45) is employed as MS refrigerant. The mixtures with proper temperature glide are recommended. The thermal performance of the overall cycle can be enhanced more significantly for hot and warm climate regions, or relative low evaporation temperature applications, though a high subcooling degree is required to meet the optimum operation condition.

  • 35.
    Dai, B.
    et al.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Qi, H.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Liu, S.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Ma, M.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Zhong, Z.
    Foreign Economic Cooperation Office, Ministry of Ecology and Environment of the People's Republic of China, Beijing, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Song, M.
    Department of Human and Engineered Environmental Studies, The University of Tokyo, Chiba, Japan.
    Sun, Z.
    Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China.
    Evaluation of transcritical CO 2 heat pump system integrated with mechanical subcooling by utilizing energy, exergy and economic methodologies for residential heating2019Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 192, s. 202-220Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A transcritical CO 2 heat pump (HP) system for residential space heating integrated with direct dedicated mechanical subcooling (DMS) is proposed, and mathematical models are developed to study the annual energetic and economic performances considering the influence of frosting. The operation characteristics by adopting different heating terminals used in five typical cities are also assessed. The results show a maximum coefficient of performance (COP) is achieved at the optimum discharge pressure and subcooling degree. The COP is promoted by 24.4% and the discharge pressure is decreased by 2.093 MPa at the ambient temperature of −10 °C and water supply/return temperature of 45/40 °C. The seasonal performance factor (SPF) is enhanced more noticeably for severe cold region. For the case of Harbin using floor-coil radiator (FCR) or normal fan-coil unit (N-FCU) as heating terminal, SPF is improved by 32.0%. The highest SPF is achieved when small temperature difference fan-coil unit (STD-FCU) is employed. The exergy efficiency can also be apparently improved, especially for the cities located in severe cold region and using FCR or N-FCU as heating terminal due to the reduction in throttling loss of CO 2 system. The purchased equipment cost and electricity cost of the CO 2 HP with DMS are both lower than those of traditional CO 2 heat pump system. The CO 2 HP DMS system using STD-FCU as heating terminal shows superior economical efficiency to traditional system, with levelized annual total cost reduced by 7.51–15.27%. 

  • 36.
    Dai, Baomin
    et al.
    Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Qi, Haifeng
    Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Liu, Shengchun
    Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Zhong, Zhifeng
    Minist Ecol & Environm Peoples Republ China, Foreign Econ Cooperat Off, Beijing, Peoples R China..
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China.
    Song, Mengjie
    Univ Tokyo, Dept Human & Engn Environm Studies, Chiba 2778563, Japan..
    Ma, Muyu
    Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Sun, Zhili
    Tianjin Univ Commerce, Tianjin Key Lab Refrigerat Technol, Tianjin 300134, Peoples R China..
    Environmental and economical analyses of transcritical CO2 heat pump combined with direct dedicated mechanical subcooling (DMS) for space heating in China2019Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 198, artikel-id 111317Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An environmental and economical assessment model is developed, in order to evaluate the performances of transcritical CO2 heat pump system with dedicated mechanical subcooling (CO2 HPDMS). Introducing DMS to traditional CO2 HP system is an efficient method to reduce the primary energy consumption, which can be further decreased by using small temperature difference fan-coil unit (STD-FCU) as heating terminal. Using CO2 heat pump system for space heating is an environmentally-friendly heating method. The corresponding pollution emissions are only inferior to those of the wall hanging gas heater. The initial capital cost and operating cost of CO2 HPDMS system are both lower than those of CO2 HPBASE system, and the CO2 compressor cost accounts for about 80% of the overall initial capital cost. In contrast to other traditional heating methods, the payback periods of CO2 HPDMS system are not more than 9 years in most cases. If the CO2 compressor and electricity price are reduced by 20% and 28.79% respectively, the life cycle cost of CO2 HPDMS will be competitive to that of coal-fired boiler. In China, it is a promising way to adopt CO2 HPDMS for space heating in the near future with the assistant of electricity price subsidy and compressor price reduction.

  • 37.
    Desideri, U.
    et al.
    Università di Perugia.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Analysis and comparison between a concentrating solar and a photovoltaic power plant2014Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 113, s. 422-433Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Solar energy is a source, which can be exploited in two main ways to generate power: direct conversion into electric energy using photovoltaic panels and by means of a thermodynamic cycle. In both cases the amount of energy, which can be converted, is changing daily and seasonally, causing a discontinuous electricity production. In order to limit this drawback, concentrated solar power plants (CSP) and photovoltaic plants (PV) can be equipped with a storage system that can be configured not only for covering peak-loads but also for the base-load after the sunset or before the sunrise. In CSP plants it is the sun's thermal energy to be stored, whereas in PV applications it is the electrical energy to be stored in batteries, although this is not economically and environmentally feasible in large-scale power plants.The main aim of this paper is to study the performance of concentrated solar power plants equipped with molten salts thermal storage to cover a base load of 3MWel. In order to verify the possibility of storing effectively the thermal energy and to design a plant for base load operation, two locations were chosen for the study: Gela in southern Italy, and Luxor in Egypt. The electricity production of the CSP facilities has been analyzed and then compared with the electricity production of PV plants. Two different comparisons were done, one by sizing the PV plant to provide the same peak power and one using the same collectors surface. This paper has also highlighted some important issues in site selection and in design criteria for CSP plants used for base load operation.The high variability of the direct normal radiation during the year in southern Italy may cause several problems in CSP facilities, mainly related to the wide range of energy input from the sun. The more uniform and higher values of the solar radiation in the Egyptian location mitigates this problem and allows achieving higher efficiencies than in southern Italy. In most cases the electricity produced by the CSP plant is higher than that produced by a similar PV plant, because the presence of the storage system guarantees the continuity of electricity production even without solar radiation. An economic analysis based on the estimation of the levelized electricity cost (LEC) for both CSP and PV power plants located both in south of Italy and Egypt was carried out in order to investigate which is the most cost effective solution. In all the cases considered, the CSP facilities resulted the best option in terms of cost of electricity produced due to the continuity of energy production during the night hours.

  • 38.
    Dibdiakova, Janka
    et al.
    Norwegian Institute of Bioeconomy Research, Ås, Norway..
    Liang, Wang
    Sintef Energy Research, , Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Heating Value and Ash Content of Downy Birch Forest Biomass2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 1302-1308Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biomass from forestry sector provides an important contribution to meet the government's targets for increasing bioenergy production and utilization. Characterization of forest residues is critical for exploiting and utilizing them for energy production purpose. In present work, stem wood, stem bark, branches, top of trees from downy birch forest were sampled from different sites in South Norway and subjected to heating value and ash content measurement. Properties of different parts of trees vertically along the tree trunk and radially along the branch and crown level were assessed via the statistical model. The heating value of stem wood was in range 18.14-18.57 MJ/kg, of stem bark 18.50-18.72 MJ/kg and of branch wood 18.21-18.50 MJ/kg. The vertical dependence of heating value of downy birch stem wood was similar to that of stem bark. Regular decreasing of heating value towards the tree top was observed. Significantly higher heating value at level p<0.05∗of stem bark than the one of stem wood was observed. The ash content of downy birch branch wood did vary axially along the branch whereas there are only slight differences of ash content of branch within the crown. The stem bark has the highest ash content in range 2.0-2.5%, followed by branch wood in range of 1.0-1.6% and the lowest for stem wood in range of 0.3-0.5%.

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  • 39.
    Dibdiakova, Janka
    et al.
    Norwegian Forest & Landscape Inst, Norway.
    Wang, Liang
    Sintef Energy Res, Trondheim, Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Characterization of ashes from Pinus Sylvestris forest biomass2015Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, s. 186-191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Efficient and profitable biomass combustion is often limited by ash related operational problems. Knowledge of the ash melting and sintering is of important, in terms of predict and reduce ash-related problems in biomass-fired boilers. In this study, chemical composition and melting behaviors of ashes from the four parts of P. sylvestris trees were investigated. The four parts from Pinus sylvestris trees are stem wood, bark, branch base and twigs. A simultaneous thermal analyzer (STA) was used to characterize the melting behavior of selected biomass fuels in oxidizing atmosphere. Ash melting process was identified as the distinctive endothermic peaks on recorded DSC curves. The results showed that the stem wood of pine contains higher contents of most of the ash forming matters than other tree parts. Chemical composition of ashes from four parts of the pine tree is dominated by element Ca, K, Mg, Mn, P and Si. The K, Na and P contents in the twigs are significantly higher than that of stem wood, bark, and branch base indicating high tendency of ash melting and slagging. STA experiments indicated that the melting process of the studied fuel ashes start in the temperature range of 930-965 degrees C. Scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometry (EDX). Analyses results showed that the stem wood ash remains loose structure even after 1000 degrees C sintering treatment. But the ashes originated from top branch show sign of sintering at 1000 degrees C. The obtained results of present work can be considered as useful information within an industry interest for a prediction of the forest biomass ash melting behavior. 

  • 40.
    Ditaranto, M.
    et al.
    SINTEF Energy Research, Trondheim, Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hu, Y.
    University of South Wales, United Kingdom.
    Evaluation of a pre-combustion capture cycle based on hydrogen fired gas turbine with exhaust gas recirculation (EGR)2014Ingår i: Energy Procedia, 2014, s. 1972-1975Konferensbidrag (Refereegranskat)
    Abstract [en]

    Pre-combustion capture technology is a promising route to power generation with CO2 free emissions, by transforming the fossil hydrocarbon fuel into a hydrogen rich fuel with near zero Carbon containing species. This gaseous fuel also allows to use a high efficiency gas turbine into a coal based power plant. The gas turbine combustor however has to meet the challenge of high temperature flame responsible for unacceptable NOx emissions, and a highly reacting fuel impeding the use of conventional dry low NOx combustion technologies. The actual solution to this problem is to dilute the hydrogen fuel with up to 50% Nitrogen. This paper presents a concept where the exhaust gas of the gas turbine is recirculated (EGR) such as to deplete the air of oxygen to produce a low temperature combustion with undiluted hydrogen fuel while flame stability is still ensured by the highly reactive properties of hydrogen. The study compares the concept with a cycle using Selective Catalytic Reduction for NOx control.

  • 41.
    Ditaranto, M.
    et al.
    SINTEF Energy Research, Trondheim, Norway .
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Løvås, T.
    Norwegian University of Science and Technology, Trondheim, Norway .
    Concept of hydrogen fired gas turbine cycle with exhaust gas recirculation: Assessment of combustion and emissions performance2015Ingår i: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 37, s. 377-383Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A novel gas turbine cycle concept applicable to power plants with pre-combustion CO<inf>2</inf> capture or integrated gasification combined cycle (IGCC) is presented. These power plants use a hydrogen rich fuel with high reactive combustion properties which makes fuel dilution necessary to achieve low NOx emissions. The proposed novel gas turbine arrangement is set up as to avoid both fuel dilution and its consequent efficiency penalty, and breakthrough in low NOx combustion technology. In this concept, a high exhaust gas recirculation (EGR) rate is applied in order to generate an oxygen depleted working fluid entering the combustor, enough to reduce the high reactivity of hydrogen rich fuels. As a result, the combustion temperature in this environment is inherently limited, thus, keeping NOx formation rate low. A first order assessment of the combustion characteristics under such gas turbine operating conditions is made in the light of a numerical analysis of stability and NOx emissions potential. Both diffusion and premixed types combustor are considered according to the selected EGR rate. It is first shown that the flame stability could be maintained at EGR rates well above the maximum EGR limit found in conventional natural gas fired gas turbines. The study further shows that at these high EGR rates, considerable reductions in NOx emissions can be expected. The conclusion of this first order analysis is that there is a true potential in reducing the efficiency penalty induced by diluting the fuel in power plants with pre-combustion CO<inf>2</inf> capture. 

  • 42.
    Dong, Beibei
    et al.
    Tianjin Univ Commerce, Key Lab Refrigerat Technol Tianjin, Peoples R China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Univ Commerce, Key Lab Refrigerat Technol Tianjin, Peoples R China.
    Zhu, Kai
    Tianjin Univ Commerce, Key Lab Refrigerat Technol Tianjin, Peoples R China.
    PVTxy Properties of CO2 Mixtures for CCS: An Update of Experimental Data and Models Since 20092018Ingår i: JOINT INTERNATIONAL CONFERENCE ON ENERGY, ECOLOGY AND ENVIRONMENT ICEEE 2018 AND ELECTRIC AND INTELLIGENT VEHICLES ICEIV 2018, DESTECH PUBLICATIONS, INC , 2018Konferensbidrag (Refereegranskat)
    Abstract [en]

    The latest progress on the experimental data and theoretical models regarding PVTxy properties of CO2 mixtures has been updated. This review shows that more experimental data are available, such as the vapor liquid equilibrium (VLE) of CO2/NO and the density of CO2/O-2. But there are still some clear deficiencies: for example, there have been no data on VLE of CO2/COS and density of CO2/NH3; there are only few points on VLE of CO2/NH3 and CO2/N2O, and density of binary mixtures containing CO, N2O4, COS and H2S. Several new models exhibit advantages for calculating PVTxy properties of CO2 mixtures. For example, Equation of State for Combustion Gases and Combustion Gas-like Mixtures (EOS-CG) shows better accuracy on both phase equilibrium and density than GERG-2008 except for the critical region. Peng-Robinson+ residual Helmholtz energy-based model (PR + EOS/(E,Wilson)(ares)) displays significant improvement in the representation of high-pressure critical region (deviation decreasing from 12.6% to 1% for CO2/O-2/N-2) and wider application of polar and non-polar mixtures for VLE.

  • 43.
    Dong, Shuaili
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. China Univ Petr, Beijing, Peoples R China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhang, Qi
    China Univ Petr, Beijing, Peoples R China..
    Yu, Zhixin
    Univ Stavanger, Dept Energy & Petr Engn, Stavanger, Norway..
    Volatility of electricity price in Denmark and Sweden2019Ingår i: INNOVATIVE SOLUTIONS FOR ENERGY TRANSITIONS / [ed] Yan, J Yang, HX Li, H Chen, X, ELSEVIER SCIENCE BV , 2019, s. 4331-4337Konferensbidrag (Refereegranskat)
    Abstract [en]

    Under the pressure of global environmental climate change, all countries in the world are developing renewable energy such as hydropower, wind energy, and solar energy As a result, the electricity price varies in different patterns depending on the penetration of renewable energy. In this paper, a non-parametric model is employed to analyze the historical data of electricity spot price from Danish price areas of the Nord Pool (with high percentage of wind power), Swedish price areas of the Nord Pool (with high percentage of hydropower) and PJM market (with little renewable energy penetrated). The objective is to deeply understand the influence of renewable energies on electricity price volatility. It is found that electricity prices are more stable in Swedish price areas as hydropower is a more stable energy source. The electricity price in PJM market is also comparatively stable, only more volatile than Swedish market, as fossil fuels are dominant energy resources. For Danish price areas, the volatility of electricity prices is clearly affected by wind power, which is a highly intermittent energy resource.

  • 44.
    Du, F.
    et al.
    Department of Electronic and Electric Engineering, University of Strathclyde, Glasgow, United Kingdom.
    Zhang, J.
    Department of Electronic and Electric Engineering, University of Strathclyde, Glasgow, United Kingdom.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Galloway, S.
    Department of Electronic and Electric Engineering, University of Strathclyde, Glasgow, United Kingdom.
    Lo, K. L.
    Department of Electronic and Electric Engineering, University of Strathclyde, Glasgow, United Kingdom.
    Modelling the impact of social network on energy savings2016Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 178, s. 56-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is noted that human behaviour changes can have a significant impact on energy consumption, however, qualitative study on such an impact is still very limited, and it is necessary to develop the corresponding mathematical models to describe how much energy savings can be achieved through human engagement. In this paper a mathematical model of human behavioural dynamic interactions on a social network is derived to calculate energy savings. This model consists of a weighted directed network with time evolving information on each node. Energy savings from the whole network is expressed as mathematical expectation from probability theory. This expected energy savings model includes both direct and indirect energy savings of individuals in the network. The savings model is obtained by network weights and modified by the decay of information. Expected energy savings are calculated for cases where individuals in the social network are treated as a single information source or multiple sources. This model is tested on a social network consisting of 40 people. The results show that the strength of relations between individuals is more important to information diffusion than the number of connections individuals have. The expected energy savings of optimally chosen node can be 25.32% more than randomly chosen nodes at the end of the second month for the case of single information source in the network, and 16.96% more than random nodes for the case of multiple information sources. This illustrates that the model presented in this paper can be used to determine which individuals will have the most influence on the social network, which in turn provides a useful guide to identify targeted customers in energy efficiency technology rollout programmes.

  • 45.
    Du, Y.
    et al.
    College of Electronics and Information Engineering, Tongji University, Shanghai, China.
    Wang, C.
    College of Electronics and Information Engineering, Tongji University, Shanghai, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Song, Jingjing
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, B.
    School of Mechanical Engineering, Hubei University of Arts and Science, Hubei Province, China.
    Clustering heat users based on consumption data2019Ingår i: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, s. 3196-3201Konferensbidrag (Refereegranskat)
    Abstract [en]

    In today's district heating (DH) energy market, it is common to use user functional categories in price models to determine the heat price. However, users in the same category do not necessarily have the same energy consumption patterns, which potentially leads to unfair prices and many other practical issues. Taking into account heat usage characteristics, this work proposes two data-driven methods to cluster DH users to identify similar usage patterns, using practical energy consumption data. Efforts are focused on extracting representative features of users from their daily usage profiles and duration curves, respectively. Employing clustering based on these features, the resulting typical usage patterns and user category distributions are discussed. Our results can serve as potential inputs for future energy price models, demand-side management, and load reshaping strategies.

  • 46.
    Frost, Anna. E.
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Maher, Azaza
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Patterns and temporal resolution in commercial and industrial typical load profiles2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 2684-2689Artikel i tidskrift (Refereegranskat)
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  • 47.
    Galanopoulos, Christos
    et al.
    Bremen Univ, Inst Environm Sci & Technol, D-28359 Bremen, Germany..
    Yan, Jinying
    KTH Royal Inst Technol, Chem Engn, SE-10044 Stockholm, Sweden.;Vattenfall AB, R&D, SE-16992 Stockholm, Sweden..
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Liu, Longcheng
    KTH Royal Inst Technol, Chem Engn, SE-10044 Stockholm, Sweden..
    Impacts of acidic gas components on combustion of contaminated biomass fuels2018Ingår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 111, s. 263-277Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The formation of high concentrations of acid gases; in combustion with large variations in fuel qualities, represents a major challenge for energy production from contaminated biomass fuels. This paper provides a comprehensive evaluation of the effects of acid gas formation and retention in the combustion of recycled wood fuels. A model has been developed based on the chemical reactions involved and empirical correlations from plant monitoring and testing. The model has been used to study the behaviour of acidic gas components in critical stages of a bubbling fluidised bed boiler process. Results indicate that the variation in type of fuel contamination is the most important issue to deal with in the combustion of recycled wood fuels. Peaks in the flue gas chlorine concentrations cannot be suppressed easily by conventional flue gas cleaning measures. Upon applying ammonium sulphate dosing for the protection of chlorine induced corrosions, it is sometimes difficult to maintain the required S/Cl ratio when large variations of fuel chlorine occur. Moreover, a high level of chlorine in the fuel can also indirectly affect the emission control of sulphur dioxide because it would require an increased level of ammonium sulphate decomposition, which results in a high level of SO2 in flue gas. The study also shows a beneficial effect of the recirculation of quench water from the flue gas condenser to the boiler. It offers opportunities for the optimisation of flue gas cleaning and flue gas condensation, for improving the efficiencies of water and wastewater treatment, as well as for emission reduction with a sustainable way.

  • 48.
    Guo, K.
    et al.
    University of Stavanger, Stavanger, Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yu, Z.
    University of Stavanger, Stavanger, Norway.
    In-situ heavy and extra-heavy oil recovery: A review2016Ingår i: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 185, s. 886-902Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to the growing global energy demand and increasingly limited availability of conventional or easy-to-produce crude oils, extensive attention is being paid to the exploitation of unconventional heavy and extra-heavy oils. However, their inherent properties, characterized by high viscosity and poor mobility, coupled with the complex reservoir configuration, make the desired recovery processes very challenging. Although several in-situ recovery techniques have been employed in oil reservoirs worldwide, most of them are still suffering from low sweep and displacement efficiencies, high capital investment, potential formation damage and negative environmental footprints. This paper aims to provide a comprehensive review of the existing in-situ heavy oil recovery techniques, which fall into three categories of thermal injection, chemical injection and gas injection. Different aspects including the fundamental principles, main features, applicability, and limitations of these recovery processes are elaborated sequentially to illustrate the current technology status. Underlying mechanisms causing the relatively low recovery factors will also be pinpointed. Furthermore, this paper focuses on the technology using novel and active catalysts for simultaneous heavy oil upgrading and recovery, especially in the case of metallic nanocatalysts. Rationales, advantages and challenges regarding this in-situ catalytic upgrading technology will be extensively described for their potential implementation in fields. It is noteworthy that many recovery techniques are still limited to the laboratory scale with needs for further investigations. Therefore, this paper also covers the evaluation standards and analytical methodologies of heavy and extra-heavy oil recovery to establish experimental screening criteria. In the end, economic and environmental aspects of the in-situ catalytic upgrading technology have been briefly discussed. The objective of this review is to present a wide range of expertise related to the in-situ heavy oil recovery processes, and to introduce the in-situ catalytic upgrading technology as an effective and environmental friendly heavy oil recovery process.

  • 49.
    Guo, K.
    et al.
    Univ Stavanger, Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yu, Zhixin
    Univ Stavanger, Norway.
    Size-Dependent Catalytic Activity of Monodispersed Nickel Nanoparticles for the Hydrolytic Dehydrogenation of Ammonia Borane2018Ingår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 1, s. 517-525Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nickel (Ni) nanoparticles (NPs) with controlled sizes in the range of 4.9-27.4 nm are synthesized by tuning the ratio of the nickel acetylacetonate precursor and trioctylphosphine in the presence of oleylamine. X-ray diffraction and transmission electron microscopy confirm the formation of the metallic Ni crystal phase and their monodispersed nature. These Ni NPs are found to be effective catalysts for the hydrolytic dehydrogenation of ammonia borane, and their catalytic activities are size-dependent. A volcano-type activity trend is observed with 8.9 nm Ni NPs presenting the best catalytic performance. The activation energy and turnover frequency (TOF) of the 8.9 nm NP catalyst are further calculated to be 66.6 kJ·mol-1 and 154.2 molH2·molNi -1·h-1, respectively. Characterization of the spent catalysts indicates that smaller-sized NPs face severe agglomeration, resulting in poor stability and activity. Three carbon support materials are thus used to disperse and stabilize the Ni NPs. It shows that 8.9 nm Ni NPs supported on Ketjenblack (KB) exhibit higher activity than that supported on carbon nanotubes and graphene nanoplatelets. The agglomeration-induced activity loss is further illustrated by immobilizing 4.9 nm Ni NPs onto KB, which exhibits significantly enhanced activity with a high TOF of 447.9 molH2·molNi -1·h-1 as well as an excellent reusability in the consecutive dehydrogenation of ammonia borane. The high catalytic performance can be attributed to the intrinsic activity of nanoparticulate Ni and the improved activity and stability due to the strong Ni/KB metal-support interactions.

  • 50.
    Guo, Kun
    et al.
    Univ Stavanger, Dept Petr Engn, N-4036 Stavanger, Norway.;Univ Stavanger, Natl IOR Ctr Norway, N-4036 Stavanger, Norway..
    Hansen, Vidar Folke
    Univ Stavanger, Dept Mech & Struct Engn & Mat Sci, N-4036 Stavanger, Norway..
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Malardalen Univ, Dept Energy Bldg & Environm, S-72123 Vasteras, Sweden..
    Yu, Zhixin
    Univ Stavanger, Dept Petr Engn, N-4036 Stavanger, Norway.;Univ Stavanger, Natl IOR Ctr Norway, N-4036 Stavanger, Norway..
    Monodispersed nickel and cobalt nanoparticles in desulfurization of thiophene for in-situ upgrading of heavy crude oil2018Ingår i: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 211, s. 697-703Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Monodispersed nickel (Ni) and cobalt (Co) nanoparticles (NPs) with different sizes are synthesized via the thermal decomposition of organometallic precursors by controlling the reaction temperature and surfactant amount. X-ray diffraction analysis of the as-prepared NP samples shows the formation of cubic Ni metal phases with good crystallinity, while the cubic Co metal samples are semi-amorphous. Transmission electron microscopy characterization further confirms that two Ni NP samples with average sizes of 9 and 27 nm, and Co NPs with an average size of 6 nm are successfully prepared with a narrow size distribution. Furthermore, catalytic performance of these monodispersed NPs towards the hydrodesulfurization (HDS) reaction, which plays a pivotal role in the upgrading of heavy crude oil, is evaluated under reservoir-relevant conditions using thiophene as a sulfur-containing model compound. Different parameters including particle size, catalyst dosage, hydrogen donor ratio, temperature, and reaction duration are systematically studied to optimize the catalytic HDS performance. The morphology and size of the spent NP catalysts after the reaction are also analyzed. The results show that the 9 nm Ni NPs exhibit the best HDS activity and stability compared with other catalysts, which suggests that such well-dispersed Ni NPs are promising candidates for the in-situ upgrading and recovery of heavy crude oil from underground reservoirs.

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