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  • 101.
    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.

  • 102.
    Chen, Yushun
    et al.
    Chinese Academy of Sciences, Wuhan, China.
    Zhang, Shuanghu
    China Institute of Water Resources and Hydropower Research, Beijing, China .
    Huang, Desheng
    Ministry of Environmental Protection of People's Republic of China, Policy Research Center for Environment and Economy, Beijing, China .
    Li, Bailian
    University of California, Riverside, Riverside, United States .
    Liu, Junguo
    South University of Science and Technology of China, Shenzhen, China .
    Liu, Wenjin
    Orient Landscape Industry Group Ltd., Beijing, China.
    Ma, Jing
    China Institute of Water Resources and Hydropower Research, State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, Beijing, China .
    Wang, Fang
    China Institute of Water Resources and Hydropower Research, State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, Beijing, China .
    Wang, Yong
    Alabama A and M University, Huntsville, United States .
    Wu, Shengjun
    Chinese Academy of Sciences, Beijing, China .
    Wu, Yegang
    Shanghai BoDa Development Corporation, Shanghai, China .
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Guo, Chuanbo
    Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China .
    Xin, Wei
    Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China .
    Wang, Hao
    China Institute of Water Resources and Hydropower Research, Beijing, China .
    The development of China's Yangtze River Economic Belt: how to make it in a green way?2017Ingår i: Science Bulletin, ISSN 2095-9273, Vol. 62, nr 9, s. 648-651Artikel i tidskrift (Refereegranskat)
  • 103.
    Chiaramonti, D.
    et al.
    Univ Florence, Italy.
    Maniatis, K.
    Univ Florence, Italy.
    Tredici, M.R
    Univ Florence, Italy.
    Verdelho, V.
    EABA, Lisbon, Portugal.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH, Stockholm, Sweden.
    Life Cycle Assessment of Algae Biofuels: Needs and challenges2015Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 154, s. 1049-1051Artikel i tidskrift (Övrigt vetenskapligt)
  • 104.
    Choi, Byungchul
    et al.
    Chonnam Natl Univ, South Korea.
    Park, Su Han
    Chonnam Natl Univ, South Korea.
    Chiarmonti, David
    RE CORD Renewable Energy COnsortium R&D, Garbagnate Monastero, LC, Ital.
    Bae, Hyeun-Jong
    Chonnam Natl Univ, South Korea.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol KTH, Stockholm, Sweden.
    Sustainable alcohol fuels promoting mobility and climate stabilization: The 21st International Symposium on Alcohol Fuels2015Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 160, s. 561-565Artikel i tidskrift (Refereegranskat)
  • 105.
    Chusova, Olga
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Remediation of TNT-contaminated water by using industrial low-cost residue pine bark2015Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    In the process of demilitarization of explosives, army ammunition plants generate a waste stream known as pink water. The principal component of the wastewater is the nitro-aromatic compound 2,4,6-trinitrotoluene (TNT). Although the persistence of TNT when dissolved in surface water is very limited due to its susceptibility to photo- and biotransformation, discharge of pink water to the environment has been prohibited in Sweden, the U.S. and many other countries for decades because of the toxicity of the compound and its metabolites to various ecological receptors.

    The most frequently used method for treatment of pink water in Sweden today is adsorption on activated carbon, which as well as being costly, creates a sludge that must be incinerated off site.

    In many countries, the timber industry residue pine bark is discarded and has no high value application. The overall aim of this thesis was to investigate the potential of pine bark for the removal of TNT from contaminated water such as pink water. Several batch studies and a column experiment were conducted. Acetonitrile extraction of pine bark and 16S rRNA sequencing for analysis of the indigenous bacterial community of pine bark were used to investigate its performance in the treatment of pink water.

    The results show that pine bark has great potential as an adsorbent medium for TNT from contaminated pink water. Simultaneous use of biotransformation and adsorption methods was shown to be an improvement over adsorption alone for the removal of TNT from contaminated water bodies. Pine bark showed higher affinity towards the amino metabolites of TNT than for TNT itself. Molecular analysis of the indigenous microbial community of pine bark and chemical analysis of its acetonitrile extracts provided evidence for its ability to biotransform TNT and its metabolites. The efficiency of the transformation was enhanced by the addition of glucose and/or inoculum.

    Overall, this work demonstrates the versatility of this organic industrial residue with respect to pink water treatment. Not only does it have a high affinity towards TNT and its amino metabolites, but its native microbial community even in the absence of external inoculation can also be taken advantage of, opening new possibilities for remediation of pink water.

  • 106.
    Chusova, Olga
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nolvak, H.
    Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, Tartu 51014, Estonia.
    Nehrenheim, Emma
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Truu, J.
    University of Tartu, Estonia.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Oopkaup, K.
    University of Tartu, Estonia.
    Truu, M.
    University of Tartu, Estonia.
    Effect of pine bark on the biotransformation of trinitrotoluene and on the bacterial community structure in a batch experiment2014Ingår i: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 35, nr 19, s. 2456-2465Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Pine bark, a low-cost industrial residue, has been suggested as a promising substitute for granular activated carbon in the on-site treatment of water contaminated with 2,4,6-trinitrotoluene (TNT). However, the complex organic structure and indigenous microbial community of pine bark have thus far not been thoroughly described in the context of TNT-contaminated water treatment. This two-week batch study examined the removal efficiency of TNT from water by (1) adsorption on pine bark and (2) simultaneous adsorption on pine bark and biotransformation by specialized TNT-biotransforming microbial inocula. The bacterial community composition of experimental batches, inocula and pine bark, was profiled by Illumina sequencing of the V6 region ofthe 16S rRNA gene. The results revealed that the inocula and experimental batches were dominated by phylotypes belonging to the Enterobacteriaceae family and that the tested inocula had good potential for TNT biotransformation. The type of applied inocula had the most profound effect on the TNT-transforming bacterial community structure in the experimental batches. The indigenous microbial community of pine bark harboured phylotypes that also have a potential to degrade TNT. Altogether, the combination of a specialized inoculum and pine bark proved to be the most efficient treatment option for TNT-contaminated water.

  • 107.
    Chusova, Olga
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nõlvak, H.
    University of Tartu, Tartu, Estonia.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Truu, J.
    University of Tartu, Tartu, Estonia.
    Truu, M.
    University of Tartu, Tartu, Estonia.
    Oopkaup, K.
    University of Tartu, Tartu, Estonia.
    Nehrenheim, Emma
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Biotransformation of pink water TNT on the surface of a low-cost adsorbent pine bark2015Ingår i: Biodegradation, ISSN 0923-9820, E-ISSN 1572-9729, Vol. 26, nr 5, s. 375-386Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This two-week anaerobic batch study evaluated 2,4,6-trinitrotoluene (TNT) removal efficiency from industrial pink water by (1) adsorption on low-cost adsorbent pine bark, and (2) adsorption coupled with TNT biotransformation by specialised microbial communities. Samples of the supernatant and acetonitrile extracts of pine bark were analysed by HPLC, while the composition of the bacterial community of the experimental batches, inocula and pine bark were profiled by high-throughput sequencing the V6 region of the bacterial 16S rRNA gene. Integrated adsorption and biotransformation proved to be the most efficient method for TNT removal from pink water. The type of applied inoculum had a profound effect on TNT removal efficiencies and microbial community structures, which were dominated by phylotypes belonging to the Enterobacteriaceae family. The analysis of acetonitrile extracts of pine bark supported the hypothesis that the microbial community indigenous to pine bark has the ability to degrade TNT.

  • 108.
    Cuneo, A.
    et al.
    Thermochemical Power Group, Università di Genova, Italy.
    Zaccaria, Valentina
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Tucker, D.
    U.S. DOE National Energy Technology Laboratory, Morgantown, United States.
    Sorce, A.
    Thermochemical Power Group, Università di Genova, Italy.
    Gas turbine size optimization in a hybrid system considering SOFC degradation2018Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 230, s. 855-864Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The coupling of a pressurized solid oxide fuel cell (SOFC) and a gas turbine has been proven to result in extremely high efficiency and reduced emissions. The presence of the gas turbine can improve system durability compared to a standalone SOFC, because the turbomachinery can supply additional power as the fuel cell degrades to meet the power request. Since performance degradation is an obstacles to SOFC systems commercialization, the optimization of the hybrid system to mitigate SOFC degradation effects is of great interest. In this work, an optimization approach was used to innovatively study the effect of gas turbine size on system durability for a 400 kW fuel cell stack. A larger turbine allowed a bigger reduction in SOFC power before replacing the stack, but increased the initial capital investment and decreased the initial turbine efficiency. Thus, the power ratio between SOFC and gas turbine significantly influenced system economic results.

  • 109.
    Da Silva, Edna
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Säterskog, M.
    Saab AB, Linköping, Sweden.
    Camacho, R. G. R.
    Federal University of Itajubá, Itajubá, MG, Brazil.
    Sarmiento, A. L. E.
    FederalCenter of Technology Education, Rio de Janeiro, RJ, Brazil.
    Preliminary design optimization of an organic Rankine cycle radial turbine rotor2017Ingår i: PROCEEDINGS OF THE ASME TURBO EXPO: TURBINE TECHNICAL CONFERENCE AND EXPOSITION, 2017, VOL 3, American Society of Mechanical Engineers (ASME) , 2017, Vol. 3, artikel-id V003T06A018Konferensbidrag (Refereegranskat)
    Abstract [en]

    The present study describes the application of a preliminary design approach for the optimization of an organic Rankine cycle radial turbine. Losses in the nozzle the rotor have initially been modelled using a mean-line design approach. The work focuses on a typical small-scale application of 50 kW, and two working fluids, R245fa (1,1,1,3,3,-pentafluoropropane) and R236fa (1,1,1,3,3,3-hexafluoropropane) are considered for validation purposes. Real gas formulations have been used based on the NIST REFPROP database. The validation is based on a design from the literature, and the results demonstrate close agreement the reference geometry and thermodynamic parameters. The total-to-total efficiencies of the reference turbine designs were 72% and 79%. Following the validation exercise, an optimization process was performed using a controlled random search algorithm with the turbine efficiency set as the figure of merit. The optimization focuses on the R245fa working fluid since it is more suitable for the operating conditions of the proposed cycle, enables an overpressure in the condenser and allows higher system efficiency levels. The R236fa working fluid was also used for comparison with the literature, and the reason is the positive slope of the saturation curve, somehow is possible to work with lower temperatures. Key preliminary design variables such as flow coefficient, loading coefficient, and length parameter have been considered. While several optimized preliminary designs are available in the literature with efficiency levels of up to 90%, the preliminary design choices made will only hold true for machines operating with ideal gases, i.e. typical exhaust gases from an airbreathing combustion engine. For machines operating with real gases, such as organic working fluids, the design choices need to be rethought and a preliminary design optimization process needs to be introduced. The efficiency achieved in the final radial turbine design operating with R245fa following the optimization process was 82.4%. A three-dimensional analysis of the flow through the blade section using computational fluid dynamics was carried out on the final optimized design to confirm the preliminary design and further analyze its characteristics.

  • 110.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    An overview of thermal biomass conversion technologies2013Ingår i: Technologies for Converting Biomass to Useful Energy: Combustion, gasification, pyrolysis, torrefaction and fermentation / [ed] Erik Dahlquist, CRC Press, 2013, 1, s. 1-4Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Officially the use of biomass for energy use globally is only 10-13 % of the total energy demand of 140 000 TWh/y. Still, the production of biomass annually is in the range of 270 000 TWh/y. Most of it obviously is not used very efficiently, although some is also used as food. There is thus a need for new methods for converting biomass into refined products like chemicals, fuels, wood and paper products, heat, cooling and electric power. The different type of conversion methods covered is biogas production, bio-ethanol production, torrefaction, pyrolysis, high temperature gasification and combustion. These methods are covered as well as principals for controlling the processes. The suitability for the different methods for different type of biomass as well as different versions of the methods is presented – both existing methods and those being developed for the future. System optimization using modeling methods and simulation is covered as well as analysis of advantages of different solutions. Many key-experts from all over the world are presenting the keys of their specialties to give us an up-to-date view of the situation all over the world. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 111.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Biomass as Energy Source: Resources, Systems and Applications2013Samlingsverk (redaktörskap) (Refereegranskat)
    Abstract [en]

    The use of energy is approximately 140 000 TWh per year globally. It is then interesting to note that biomass production is approximately 270 000 TWh/year, or roughly twice as much. This shows that biomass is not a marginal energy resource but more than enough to cover all our needs for both energy and food, if just the biomass is used efficiently. There has been a lot of discussion about using food for energy. This is quite relevant, and if we look at all resources like agricultural and forestry waste, the need to use food for energy is not needed. We can cover all our needs anyhow. The resources we have available and some other aspects like using the energy efficiently is covered in this book. One way of using energy efficiently is to use waste biomass or cellulosic materials in bio refineries, where production of fibers and products from fibers is combined with production of most chemicals we need in our daily life. This includes clothes, soap, perfume, medicines etc. Conventional pulp and paper applications are also covered. But it also includes bio-fuel for vehicles and even fuel for aviation is covered. It also includes production of heat, cool and electricity. That is, biomass can cover all our needs. The difficulty is to use the resources efficiently without harming the productivity long term. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 112.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Energy, different forms2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 245-264Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 113.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Energy resources and regional balances2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 157-179Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 114.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Environment friendly contribution of the microbes to energy conversion2016Ingår i: Microbiological Industrial Hygiene, Nova Science Publishers, Inc. , 2016, s. 349-359Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    There is enough biomass annual growth to replace all fossil fuels used principally. Still, only a small portion of this is actually used efficiently. In this chapter we discuss the resources and how they can be utilized in different ways. Especially use in bio-refineries is discussed, where both full scale plants and future directions is addressed. Concerning future directions for bio-refineries an EU project ABOWE demonstrated how organic waste can be used for production of chemicals like 2,3-butanediol, valeric acid, hydrogen and other organic acids. After this crops for food is discussed and how waste from agriculture can be utilized as source for production of the chemicals and crops with different metabolic paths are discussed briefly, C3, C4 and CAM crops. C3 crops are the most common while C4 and CAM have more efficient systems for CO2 fixation and also have much higher efficiency from sun to chemicals. Also other applications are presented like extraction of metals using microorganisms and production of meat replacement using fungi. Finally obstacles for the efficient utilization of biomass are discussed. 

  • 115.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Från industri till akademi2013Ingår i: Bilden av ingenjören / [ed] Yvonne Eriksson och Ildiko Asztalos Morell, Stockholm: Carlsson , 2013, 1, s. 116--129Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [sv]

    Ingenjörens roll i samhället. Genusaspekter, historiska orsaker, internationella och nationella perspektiv.

  • 116.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Impact on climate and environment2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 265-268Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 117.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nonorganic and fossil resources: Known and estimated resources2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 181-205Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 118.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Population development, demography and historical perspective2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 73-92Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 119.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Technologies for Converting Biomass to Useful Energy: combustion, gasification, pyrolysis, torrefaction and fermentation2013Samlingsverk (redaktörskap) (Refereegranskat)
    Abstract [en]

    Officially the use of biomass for energy use globally is only 10-13 % of the total energy demand of 140 000 TWh/y. Still, the production of biomass annually is in the range of 270 000 TWh/y. Most of it obviously is not used very efficiently, although some is also used as food. There is thus a need for new methods for converting biomass into refined products like chemicals, fuels, wood and paper products, heat, cooling and electric power. The different type of conversion methods covered is biogas production, bio-ethanol production, torrefaction, pyrolysis, high temperature gasification and combustion. These methods are covered as well as principals for controlling the processes. The suitability for the different methods for different type of biomass as well as different versions of the methods is presented – both existing methods and those being developed for the future. System optimization using modeling methods and simulation is covered as well as analysis of advantages of different solutions. Many key-experts from all over the world are presenting the keys of their specialties to give us an up-to-date view of the situation all over the world. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 120.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Bundschuh, Jochen
    Biomass in different biotopes – an extensive resource2013Ingår i: Biomass as Energy Source: Resources, Systems and Applications / [ed] Erik Dahlquist, Taylor & Francis Group, 2013, 1, s. 87-108Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The use of energy is approximately 140 000 TWh per year globally. It is then interesting to note that biomass production is approximately 270 000 TWh/year, or roughly twice as much. This shows that biomass is not a marginal energy resource but more than enough to cover all our needs for both energy and food, if just the biomass is used efficiently. There has been a lot of discussion about using food for energy. This is quite relevant, and if we look at all resources like agricultural and forestry waste, the need to use food for energy is not needed. We can cover all our needs anyhow. The resources we have available and some other aspects like using the energy efficiently is covered in this book. One way of using energy efficiently is to use waste biomass or cellulosic materials in bio refineries, where production of fibers and products from fibers is combined with production of most chemicals we need in our daily life. This includes clothes, soap, perfume, medicines etc. Conventional pulp and paper applications are also covered. But it also includes bio-fuel for vehicles and even fuel for aviation is covered. It also includes production of heat, cool and electricity. That is, biomass can cover all our needs. The difficulty is to use the resources efficiently without harming the productivity long term. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 121.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Bundschuh, Jochen
    Pulp and paper industry – trends for the future2013Ingår i: Biomass as Energy Source: Resources, Systems and Applications / [ed] Erik Dahlquist, Taylor & Francis Group, 2013, 1, s. 229-234Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The use of energy is approximately 140 000 TWh per year globally. It is then interesting to note that biomass production is approximately 270 000 TWh/year, or roughly twice as much. This shows that biomass is not a marginal energy resource but more than enough to cover all our needs for both energy and food, if just the biomass is used efficiently. There has been a lot of discussion about using food for energy. This is quite relevant, and if we look at all resources like agricultural and forestry waste, the need to use food for energy is not needed. We can cover all our needs anyhow. The resources we have available and some other aspects like using the energy efficiently is covered in this book. One way of using energy efficiently is to use waste biomass or cellulosic materials in bio refineries, where production of fibers and products from fibers is combined with production of most chemicals we need in our daily life. This includes clothes, soap, perfume, medicines etc. Conventional pulp and paper applications are also covered. But it also includes bio-fuel for vehicles and even fuel for aviation is covered. It also includes production of heat, cool and electricity. That is, biomass can cover all our needs. The difficulty is to use the resources efficiently without harming the productivity long term. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 122.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Engvall, Klas
    KTH.
    Liliedahl, Trul
    KTH.
    Biomass and black liquor gasification2013Ingår i: Technologies for Converting Biomass to Useful Energy: COMBUSTION, GASIFICATION, PYROLYSIS, TORREFACTIONAND FERMENTATION / [ed] Erik Dahlquist, CRC Press, 2013, 1, s. 175-216Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Officially the use of biomass for energy use globally is only 10-13 % of the total energy demand of 140 000 TWh/y. Still, the production of biomass annually is in the range of 270 000 TWh/y. Most of it obviously is not used very efficiently, although some is also used as food. There is thus a need for new methods for converting biomass into refined products like chemicals, fuels, wood and paper products, heat, cooling and electric power. The different type of conversion methods covered is biogas production, bio-ethanol production, torrefaction, pyrolysis, high temperature gasification and combustion. These methods are covered as well as principals for controlling the processes. The suitability for the different methods for different type of biomass as well as different versions of the methods is presented – both existing methods and those being developed for the future. System optimization using modeling methods and simulation is covered as well as analysis of advantages of different solutions. Many key-experts from all over the world are presenting the keys of their specialties to give us an up-to-date view of the situation all over the world. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 123.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hakalehto, Elias
    Silveira, Semida
    KTH.
    Concluding remarks and perspectives on the future of energy systems using biomass2013Ingår i: Biomass as Energy Source: Resources, Systems and Applications / [ed] Erik Dahlquist, Taylor & Francis Group, 2013, 1, s. 263-266Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    The use of energy is approximately 140 000 TWh per year globally. It is then interesting to note that biomass production is approximately 270 000 TWh/year, or roughly twice as much. This shows that biomass is not a marginal energy resource but more than enough to cover all our needs for both energy and food, if just the biomass is used efficiently. There has been a lot of discussion about using food for energy. This is quite relevant, and if we look at all resources like agricultural and forestry waste, the need to use food for energy is not needed. We can cover all our needs anyhow. The resources we have available and some other aspects like using the energy efficiently is covered in this book. One way of using energy efficiently is to use waste biomass or cellulosic materials in bio refineries, where production of fibers and products from fibers is combined with production of most chemicals we need in our daily life. This includes clothes, soap, perfume, medicines etc. Conventional pulp and paper applications are also covered. But it also includes bio-fuel for vehicles and even fuel for aviation is covered. It also includes production of heat, cool and electricity. That is, biomass can cover all our needs. The difficulty is to use the resources efficiently without harming the productivity long term. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

  • 124.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hellstrand, S.
    Nolby Ekostrategi, Kil, Sweden.
    Preface2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. v-viKapitel i bok, del av antologi (Refereegranskat)
  • 125.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hellstrand, StefanMälardalens högskola, Akademin för ekonomi, samhälle och teknik, Industriell ekonomi och organisation. Nolby Ekostrategi, Kil, Sweden.
    Natural resources available today and in the future: How to perform change management for achieving a sustainable world2017Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [en]

    This book focuses on providing an overview of all our available natural resources, considering the sustainability and potential for power generation of each. Energy efficiency prospects of each natural resource are examined in the context of society's key energy needs- Heating/cooling, Electric Power, Transportation and Industrial Production. Geography, climate and demographics are all discussed as key vectors impacting the comparative opportunities for self-sustenance around the globe. The authors provide in-depth coverage of renewable energy upscale and energy efficiency improvements in industry and society within a historical context, including a keen look at the variable effectiveness of different policy tools that have been used to support the transition away from unsustainable resource use. Finally, suggestions for more sustainable futures are provided, from improved policy measures, to new technological horizons in areas from offshore wind and marine energy to biogas and energy storage. 

  • 126.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hellstrand, Stefan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    System perspective2017Ingår i: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, s. 1-56Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 127.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Mirmoshtaghi, Guilnaz
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Larsson, Eva K.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Engvall, K.
    KTH Royal Institute of Technology, Stockholm, Sweden .
    Liliedahl, T.
    KTH Royal Institute of Technology, Stockholm, Sweden .
    Dong, C.
    North China Electric Power University, Beijing, China.
    Hu, X.
    North China Electric Power University, Beijing, China.
    Lu, Q.
    North China Electric Power University, Beijing, China.
    Modelling and Simulation of Biomass Conversion Processes2015Ingår i: Proceedings - 8th EUROSIM Congress on Modelling and Simulation, EUROSIM 2013, 2015, s. 506-512, artikel-id 7004995Konferensbidrag (Refereegranskat)
    Abstract [en]

    By utilizing biomass gasification, the energy contentof the biomass can be utilized to produce gas to be used forcogeneration of heat and power as well as other energy carrierssuch as fuels for vehicles. The concept is suitable forapplication to existing CHP plants as well as for utilizing spentliqour in small scale pulp and paper mills. The introductionwould enable flexible energy utilization, use of problematicfuels as well as protects the environment by e.g. avoiding therelease of toxic substances. In this paper, the possibilities todevelop this concept is discussed. In this paper we comparedifferent gasification processes with respect to what gas qualitywe get, and how the gasification can be modelled usingdifferent modelling approaches, and how these can becombined. Results from simulations are compared toexperimental results from pilot plant operations in differentscales and with different processes like CFB and BFBTechnologies, athmospheric and pressurized, and using steam,air and oxygen as oxidizing media.

  • 128.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Comparison of Gas Quality from Black Liquor and Wood Pellet Gasification Using Modelica Simulation and Pilot Plant Results2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 992-998Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and methanol etc. To perform system analysis of such integration, it is important to gain knowledge of relevant input data on expected synthesis gas composition by gasifying different types of feed stock. In this paper, the synthesis gas quality from wood pellets gasification (WPG) has been compared with black liquor gasification (BLG) through modeling and experimental results at pilot scale. In addition, the study develops regression models like Partial Least Squares (PLS) made from the experimental data. The regression models are then combined with dynamic models developed in Modelica for the investigation of dynamic energy and material balances for integrated plants. The data presented in this study could be used as input to relevant analysis using e.g. ASPEN plus and similar system analysis tools. 

  • 129.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology (KTH), Sweden.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hartwell, Philip
    BioRegional MiniMills Ltd, UK.
    Experimental and numerical investigation of pellet and black liquor gasification for polygeneration plant2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 204, s. 1066-1064Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It is vital to perform system analysis on integrated biomass gasification in chemical recovery systems in pulp and paper and heat and power plants for polygeneration applications. The proposed integration complements existing pulp and paper and heat and power production systems with production of chemicals such as methane and hydrogen. The potential to introduce gasification-based combined cycles comprising gas turbines and steam turbines to utilize black liquors and wood pellets also merits investigation. To perform such analysis, it is important to first build knowledge on expected synthesis gas composition by gasifying at smaller scale different types of feed stock. In the present paper, the synthesis gas quality from wood pellets gasification has been compared with black liquor gasification by means of numerical simulation as well as through pilot-scale experimental investigations. The experimental results have been correlated into partial least squares models to predict the composition of the synthesis gas produced under different operating conditions. The gas quality prediction models are combined with physical models using a generic open-source modelling language for investigating the dynamic performance of large-scale integrated polygeneration plants. The analysis is further complemented by considering potential gas separation using modern membrane technology for upgrading the synthesis gas with respect to hydrogen content. The experimental data and statistical models presented in this study form an important literature source for future use by the gasification and polygeneration research community on further integrated system analysis.

  • 130.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH, Energiprocesser.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH, Energiprocesser.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hartwell, Philip
    BioRegional MiniMills Ltd., United Kingdom.
    Modeling of Black Liquor Gasification2016Konferensbidrag (Refereegranskat)
  • 131.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH, Energiprocesser.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH, Energiprocesser.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hartwell, Philip
    BioRegional MiniMills Ltd., United Kingdom.
    Modeling of Wood Gasification in an Atmospheric CFB Plant2016Konferensbidrag (Refereegranskat)
  • 132.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nordlader, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Christian
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB Process Industries AB, Västerås, Sweden.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Control of waste water treatment combined with irrigation2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    In waste water treatment using biological treatment processes normally phosphorous, nitrous compounds as well as organic matterare removed.It is also important to remove or kill pathogens that otherwisecould cause diseases. The surplus of bio-sludge is used to produce biogas. In thepaper four different alternatives for system design and operations of systems was discussed. The alternatives integrates thewaste water treatment and irrigation offarmland using the water taken out from different positions in the waste water treatment plant.

  • 133.
    Dahlquist, Erik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Vassileva, Iana
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Campillo, Javier
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lundström, Lukas
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Energy efficiency improvements by renovation actions: in Lagersberg and Råbergstorp, Stoke on Trent and Allingsås2016Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report covers evaluation of some renovation projects and compares energy saving effects versus renovation costs.

    It can be seen that advanced renovation to passive house standard is significantly more expensive than “normal” renovation, but also gives significant improvement by a 62 % reduction of total energy and 85 % reduction in heat demand. The cost associated with the renovation is somewhere in the range of 130–570 €/m2, depending on how the total renovation costs are split between energy and other aspects. Probably somewhere in-between is most correct. This can be compared to mostly better heat control by measuring temperature in every third apartment and controlling heat supply to keep a constant temperature. This gives the possibility to have a significantly lower set point, 21 ºC instead of 24 ºC as earlier. Together with some other actions, 34 % energy savings were achieved at a cost of 28 €/m2. Also renovations with significantly more actions were evaluated, where the cost also is in-between.

    From this we can conclude that with more advanced and costly renovations we can achieve very strong reductions, which may be feasible if the renovation demand is high anyhow, while cheap and low cost actions can be good enough for quite good buildings.

    Also behavior with respect to energy use was evaluated. We here can see that the use is very different in different apartments depending on behavior. Energy information actions were giving positive effects on energy demand for the majority of investigated tenants, while approximately 25 % did not reduce or even increased their consumption.

  • 134.
    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.

  • 135.
    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%. 

  • 136.
    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.

  • 137.
    Dalenbäck, Jan-Olof
    et al.
    Chalmers tekniska högskola, Göteborg, Sverige.
    Lennermo, Gunnar
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Energianalys AB, Sverige.
    Andersson-Jessen, Per-Erik
    Kovacs, Peter
    Solvärme i fjärrvärmesystem: Utvärdering av primärkopplade system2013Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Sverige ärett föregångsland när det gälleratt använda solvärme i när-och fjärr-värmesystem.Under perioden 1982 till 1992 byggde vi en serie av anläggningar som alla var större än man byggt i något annat land. Stora bioenergitillgångar och ett stort behov att hitta ersättning för olja i fjärrvärme-systemen ledde parallellt till en mycket positiv utveckling för biobränsle i fjärr-värmesystem, främst flis, och tillsammans med ändrade villkor för demonstrations-anläggningar, kom intresset för stora solvärmeanläggningar av sig i Sverige.

    Med Bo01 i Malmö 2001 introducerades lokala solvärmesystem i fjärrvärme och med stöd från EU-direktiv med byggnadsfokus har det nu byggts ett antal mindre solvärmeanläggningar i anslutning till olika byggnader med fjärrvärme. De anläggningar som uppfördes på 80-och 90-talet ingick ofta i ett samordnat program med investeringsbidrag och tredjepartsutvärdering och det finns en mängd utvärderingsrapporter.De anläggningar som uppförts under 2000-talet har inte haft samma förutsättningar.Dessutom är det förhållandevis många som anslutits i fjärr-värmesystem.

    De har ofta initierats genom politiska beslut till del som ett resultat av nya krav på byggnaders energiprestanda och det finns inga andra utvärderingar än anläggningsägarnas egna. I den här rapporten görs en övergripande dokumentation och utvärdering av 22solvärmesystem som anslutits direkt till fjärrvärmesystemen och tagits i drift under perioden 2000till 2010. Utvärdering fokuserar på systemutformning, installation, driftuppföljning och värmeutbyte som kan ligga till grund för rekommendationer till nya anläggningar.

    Utvärderingen visar att många av anläggningarna har brister såväl med avseende på systemutformning som pådriftuppföljning och värmeutbyte.Det finns anlägg-ningar som ger mer än 300 kWh/år.m2solfångare, vilket får anses acceptabelt, men som medelvärde ger de 8 senast uppförda anläggningarna endast 240 kWh/år.m2 solfångare (2011-2012), varför det finns stort utrymme för förbättringar.

    Som en övergripande rekommendation föreslås att det bör genomföras ett upp-följningsprojekt under 2013 där de utvärderade anläggningarna följas upp under minst ett år så att alla fås att fungera på ett relevant sätt utgående från dess förutsättningar. Sedan bör erfarenheterna från de utvärderade anläggningarna sammanställas i en enkel projekteringsmall som kan användas i framtida anläggningar.

  • 138.
    Dall'Orto, Francesco
    et al.
    University of Parma, Italy.
    Zimmerman, Nathan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Vadiee, Amir
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Economic Aspect of Hybrid Heating and Cooling Systems in a Residential Building2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    District heating is a well-established technology; however, the use of individual heat pumps has been expanding and is now the main competitor to district heating. The prices for both electricity and district heating often vary over time because of the variation of raw material prices in the marketplace. Consequently, for the building owner it would be cost effective if they had the possibility to integrate both district heating and heat pumps. Aiding in the flexibility to switch between the two systems in order to choose the one with the lowest operating cost throughout the year. In the presented work, the modeling and control of a detached house integrated with both district heating and a heat pump are developed. The operating costs of both systems are computed considering the marketplace prices and the coefficient of performance of the heat pump, related to the external temperature. The results show that heat pumps can be well exploited during the spring and fall to cover base loads, and in the summer can be used for ambient cooling.

  • 139.
    Danish, M.
    et al.
    East China University of Science and Technology, Shanghai, China .
    Gu, X.
    East China University of Science and Technology, Shanghai, China .
    Lu, S.
    East China University of Science and Technology, Shanghai, China .
    Ahmad, A.
    Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Farooq, U.
    East China University of Science and Technology, Shanghai, China .
    Zhang, X.
    East China University of Science and Technology, Shanghai, China .
    Fu, X.
    East China University of Science and Technology, Shanghai, China .
    Miao, Z.
    East China University of Science and Technology, Shanghai, China .
    Xue, Y.
    East China University of Science and Technology, Shanghai, China .
    Efficient transformation of trichloroethylene activated through sodium percarbonate using heterogeneous zeolite supported nano zero valent iron-copper bimetallic composite2017Ingår i: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 308, s. 396-407Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Zeolite supported nano zero valent iron copper bimetallic composite (Z-nZVFe-Cu) was synthesized using an ion exchange method. The morphology and physico-chemical properties of the Z-nZVFe-Cu composite were determined using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET), energy dispersive X-ray spectra (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD). The results showed that iron and copper nano particles were well dispersed on the zeolite sheet. The degradation efficiency of trichloroethylene (TCE) achieved was more than 95% using Z-nZVFe-Cu as a heterogeneous Fenton like catalyst. An efficient removal of total organic carbon (TOC) was promoted as compared to zeolite supported iron nano composite (Z-nZVFe) and unsupported nano iron (nZVFe). Electron spin resonance (ESR) detection confirmed the intensity of hydroxyl radicals (OH[rad]) in the system. While benzoic acid (BA), a probe indicator for the quantification of OH[rad], demonstrated the higher intensity of hydroxyl radicals in Z-nZVFe-Cu as compared to Z-nZVFe and nZVFe. The less iron and copper leaching of from Z-nZVFe-Cu presented its higher stability and better catalytic activity, displaying its potential long term applications for TCE degradation in groundwater. 

  • 140.
    Danish, M.
    et al.
    East China University of Science and Technology, Shanghai, China .
    Gu, X.
    East China University of Science and Technology, Shanghai, China .
    Lu, S.
    East China University of Science and Technology, Shanghai, China .
    Zhang, X.
    East China University of Science and Technology, Shanghai, China .
    Fu, X.
    East China University of Science and Technology, Shanghai, China .
    Xue, Y.
    East China University of Science and Technology, Shanghai, China .
    Miao, Z.
    East China University of Science and Technology, Shanghai, China .
    Ahmad, A.
    Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Qureshi, A. S.
    University of Sindh, Jamshoro, Pakistan.
    The Effect of Chelating Agents on Enhancement of 1,1,1-Trichloroethane and Trichloroethylene Degradation by Z-nZVI-Catalyzed Percarbonate Process2016Ingår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 227, nr 9, artikel-id 301Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study primarily focused on the performance of 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethylene (TCE) degradation involving redox reactions in zeolite-supported nanozerovalent iron composite (Z-nZVI)-catalyzed sodium percarbonate (SPC) system in aqueous solution with five different chelating agents (CAs) including oxalic acid (OA), citric acid monohydrate (CAM), glutamic acid (GA), ethylenediaminetetraacetic acid (EDTA), and L-ascorbic acid (ASC). The experimental results showed that the addition of OA achieved almost 100 % degradation of 1,1,1-TCA and TCE. The addition of CAM and GA also significantly increased the contaminant degradation, while excessive addition of them inhibited the degradation. In contrast, EDTA and ASC showed negative impacts on 1,1,1-TCA and TCE degradation, which might be due to the strong reactivity with iron and OH● scavenging characteristics. The efficiency with CA addition on 1,1,1-TCA and TCE degradation decreased in the order of OA > CAM > GA > no CAs > EDTA > ASC. The extensive investigations using probe compound tests and scavenger tests revealed that both contaminants degraded primarily by OH● and O2 –● in chelated Z-nZVI-catalyzed SPC system. The significant improvement in 1,1,1-TCA and TCE degradation efficiency was accredited due to the (i) increase in concentration of Fe2+ and (ii) continuous generation of OH● radicals and maintenance of its quantity, ensuring more stability in the aqueous solution. Finally, the complete mineralization of 1,1,1-TCA and TCE in the OA-chelated, Z-nZVI-catalyzed SPC system was confirmed without any chlorinated intermediate by-products detected, demonstrating a great potential of this technique in the application of groundwater remediation.

  • 141.
    Danish, M
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Xu, Minhui
    East China University of Science and Technology, Shanghai, China.
    Xiang, Zhang
    East China University of Science and Technology, Shanghai, China.
    Fu, Xiaori
    East China University of Science and Technology, Shanghai, China.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Miao, Zhouwei
    East China University of Science and Technology, Shanghai, China.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Nasir, Muhammad
    IRCBM, COMSATS Institute of Information Technology, Lahore, Pakistan.
    Role of reactive oxygen species and effect of solution matrix in trichloroethylene degradation from aqueous solution by zeolite-supported nano iron as percarbonate activator2016Ingår i: Research on chemical intermediates (Print), ISSN 0922-6168, E-ISSN 1568-5675, Vol. 42, nr 9, s. 6959-6973Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The role of reactive oxygen species (ROSs) and effect of solution matrix have been investigated for the degradation of trichloroethylene (TCE). Zeolite-supported nano iron (Z-nZVI) was synthesized as an activator to catalyze sodium percarbonate (SPC) with or without hydroxylamine, i.e. as reducing agent (RA). The probe tests confirmed the generation of OH·and O2−· in the Z-nZVI activated SPC system in absence of the RA, while the presence of RA significantly increased the generation of OH· and O2−· radicals. Scavenger tests demonstrated that OH· was the main ROS responsible for TCE degradation, whereas O2−· also participated in TCE degradation. From the solution matrix perspective, the experimental results confirmed significant scavenging effects of Cl− (1.0, 10.0, and 100 mmol L−1) and HCO3− (1.0 and 10.0 mmol L−1), whereas the scavenging effects were fairly impeded at 100 mmol L−1concentration of HCO3−. On the other hand, a considerable decline in scavenging effect was observed in the presence of RA in tested Cl− and HCO3− concentration ranges. In addition, negligible scavenging effects of NO3− and SO42− anions were found in all tested concentrations. The effect of initial solution pH on catalytic activity indicated a significant increase in the TCE degradation in the presence of RA even at higher pH value of 9. The results indicated that the Z-nZVI activated SPC system in presence of RA can effectively degrade chlorinated organic solvents, but it is important to consider the intensive existence of anions in groundwater.

  • 142.
    Danish, Muhammad
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Farooq, Usman
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Qamar Zaman, Waqas
    East China University of Science and Technology, Shanghai, China.
    Fu, Xiaori
    East China University of Science and Technology, Shanghai, China.
    Miao, Zhouwei
    East China University of Science and Technology, Shanghai, China.
    Brusseau, Mark L.
    The University of Arizona, US.
    Ahmad, Ayyaz
    University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    An efficient catalytic degradation of trichloroethene in a percarbonate system catalyzed by ultra-fine heterogeneous zeolite supported zero valent iron-nickel bimetallic composite2017Ingår i: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 531, s. 177-186Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Zeolite supported nano iron-nickel bimetallic composite (Z-nZVI-Ni) was prepared using a liquid-phase reduction process. The corresponding surface morphologies and physico-chemical properties of the Z-nZVI-Ni composite were determined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray spectra (EDS), Brunauer Emmett Teller (BET) adsorption, wide angle X-ray diffractometry (WA-XRD), and Fourier transform infrared spectroscopy (FTIR). The results indicated high dispersion of iron and nickel nano particles on the zeolite sheet with an enhanced surface area. Complete destruction of trichloroethene (TCE) and efficient removal of total organic carbon (TOC) were observed by using Z-nZVI-Ni as a heterogeneous catalyst for a Fenton-like oxidation process employing sodium percarbonate (SPC) as an oxidant. The electron spin resonance (ESR) of Z-nZVI-Ni verified the generation and intensity of hydroxyl radicals (OH). The quantification of OHelucidated by using p-chlorobenzoic acid, a probe indicator, confirmed the higher intensity of OH. The transformation products were identified using GC–MS. The slow iron and nickel leaching offered higher stability and better catalytic activity of Z-nZVI-Ni, demonstrating its prospective long term applications in groundwater for TCE degradation.

  • 143.
    Danish, Muhammad
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Farooq, Usman
    East China University of Science and Technology, Shanghai, China.
    Ahmad, Ayyaz
    University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Zhang, Xiang
    East China University of Science and Technology, Shanghai, China.
    Effect of solution matrix and pH in Z-nZVI-catalyzed percarbonate system on the generation of reactive oxygen species and degradation of 1, 1, 1-trichloroethane2017Ingår i: Water Science and Technology: Water Supply, ISSN 1606-9749, E-ISSN 1607-0798, Vol. 17, nr 6, s. 1568-1578Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study primarily focuses on evaluating the effects of solution matrix and pH for the generation of reactive oxygen species (ROSs) in Z-nZVI-catalyzed sodium percarbonate (SPC) system to degrade 1,1,1-trichloroethane (1,1,1-TCA) in the absence and presence of reducing agent (RA) i.e. hydroxylamine. 1,1,1-TCA degradation was 49.5% and 95% in the absence and presence of RA. Probe tests confirmed the generation of major hydroxyl radicals (OH•) and minor superoxide species (O2–•), and scavenger tests verified the key role of OH• and less of O2–• radicals. 1,1,1-TCA degradation decreased significantly in the presence of Cl− and HCO3–, while NO3– and SO42– have negligible effects in absence of RA. Addition of RA significantly enhanced 1,1,1-TCA degradation by generating more OH• and O2–• radicals in presence of anions. 1,1,1-TCA degradation increased in acidic range (1–5) while, an inhibitive trend from neutral to basic (7–9) was observed. On the contrary, a significant increase in 1,1,1-TCA degradation was observed with addition of RA in all pH values (1–9). In conclusion, the anions and pH significantly influenced the generation and intensity of ROSs and 1,1,1-TCA was effectively degraded in Z-nZVI-catalyzed SPC system in the presence of RA.

  • 144.
    Danish, Muhammad
    et al.
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Gu, Xiaogang
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Lu, Shuguang
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Degradation of chlorinated organic solvents in aqueous percarbonate system using zeolite supported nano zero valent iron (Z-nZVI) composite2016Ingår i: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 23, nr 13, s. 13298-13307Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Chlorinated organic solvents (COSs) are extensively detected in contaminated soil and groundwater that pose long-term threats to human life and environment. In order to degrade COSs effectively, a novel catalytic composite of natural zeolite-supported nano zero valent iron (Z-nZVI) was synthesized in this study. The performance of Z-nZVI-catalyzed sodium percarbonate (SPC) in a heterogeneous Fenton-like system was investigated for the degradation of COSs such as 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethylene (TCE). The surface characteristics and morphology of the Z-nZVI composite were tested using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Total pore volume, specific surface area, and pore size of the natural zeolite and the Z-nZVI composite were measured using Brunauer-Emmett-Teller (BET) method. SEM and TEM analysis showed significant elimination of aggregation and well dispersion of iron nano particles on the framework of natural zeolite. The BET N-2 measurement analysis indicated that the surface area of the Z-nZVI composite was 72.3 m(2)/g, much larger than that of the natural zeolite (0.61 m(2)/g). For the contaminant analysis, the samples were extracted with n-hexane and analyzed through gas chromatograph. The degradation of 1,1,1-TCA and TCE in the Z-nZVI-catalyzed percarbonate system were 48 and 39 % respectively, while strong augmentation was observed up to 83 and 99 %, respectively, by adding the reducing agent (RA), hydroxyl amine (NH2OH center dot HCl). Probe tests validated the presence of OH center dot and O-2(center dot-) which were responsible for 1,1,1-TCA and TCE degradation, whereas both free radicals were strengthened with the addition of RA. In conclusion, the Z-nZVI/SPC oxidation with reducing agent shows potential technique for degradation of groundwater contaminated by 1,1,1-TCA and TCE.

  • 145.
    Danish, Muhammad
    et al.
    E China Univ Sci & Technol, Peoples R China.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Farooq, Usman
    Gujarat Univ, Gujrat, Pakistan.
    Naqvi, Salman
    Univ Teknol PETRONAS, Univ Teknol PETRONAS, Malaysia.
    Characterization of South Asian agricultural residues for potential utilization in future 'energy mix'2015Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, s. 2974-2980Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper characterizes various locally available agricultural residues in South Asian region to evaluate their potential as feedstock for renewable energy production and contributing toward solving energy crisis and environmental issues. The thermo-chemical characterization has been performed in order to determine if the residues have potential to be used in biomass conversion technologies producing combined heat and power. The characterization methods for comparing different agricultural residues include proximate and ultimate analysis, heating value, ash content, thermo gravimetric analysis (TGA) and structural composition analysis (SCA). Widely available agricultural wastes in South Asian region were selected for the characterization i.e. bagasse, almond shell, corn cob, cotton stalks, wheat straw, sawdust, corn leaf, rice husk, rice straw, and corn straw. The analysis showed that the corn cob had the highest moisture content that will result in low energy efficiency of the thermal conversion technology due to energy requirement for drying. Whereas almond shell had the lowest moisture content. Ash and volatile contents were found to be highest in rice straw and almond shell respectively. The thermo gravimetric analysis showed that most of the agricultural residues can be easily decomposed and represent potential feedstock for biomass flexible combined heat and power systems through pyrolysis or gasification. (C) 2015 Published by Elsevier Ltd.

  • 146.
    Daraei, Mahsa
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Production planning of CHP plants integrated with bioethanol production and local renewables2019Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Production planning of an energy system is dependent on parameters such as energy demand and energy conversion technologies, which are influential in making decisions on operation strategy and optimal performance of the system. In accordance with the European Union energy policy, the share of renewable resources in the energy supply is growing. Improvement in energy technology is considered to be a pathway to achieve the target of 100% renewable power supply in Sweden by 2040. Increased utilization of renewable resources in energy systems and transportation sectors as well as improved energy conversion technologies would add complexity to the systems. Development of such complex systems depends on several key parameters, including availability of local resources, changes in daily energy use behavior, market price and weather conditions. Therefore, optimization and long-term production planning of such systems will be crucial considering the alternating nature of renewable resources.  

    The aim of this thesis is to develop an optimization model for a regional energy system to provide advanced knowledge for production planning for combined heat and power (CHP) plants. The energy system in the county of Västmanland in central Sweden is used as the case for study. The regional system consists of CHP plants, heat only boilers and renewable resources. Two different optimization cases are developed for the analysis, one with increased energy supply from local renewables, and the other with integrated transport fuels production in a polygeneration system. The model includes the whole chain from availability of resources to the final energy use. 

    The effect of different parameters relating to trends in energy demand and supply on operational strategy of the studied system is investigated by developing different scenarios. The potential solar power production from grid-connected solar cells installed on the rooftops of buildings in the region is added to the system in the base scenario. Then, the first scenario analyzes the increased application of heat pumps to replace the district heating in some of the buildings in the region. The influence of electrification of the transportation system as a result of increased penetration of electric vehicles is investigated in the second scenario. Two further scenarios evaluate the effects of integration of bioethanol production with existing CHP plants and increased application of bioethanol cars and hybrid vehicles in the regional transportation system. 

    The study demonstrates the importance of production planning of the energy system at the regional scale in relation to resource availability and energy imports. The main conclusion of this thesis is that the polygeneration and increased use of heat pumps could influence the production planning of the system in terms of fuel use, plants operation, fossil-based emissions, and energy demand and import. However, increased use of hybrid vehicles represents the optimal case for the mentioned parameters.

  • 147.
    Daraei, Mahsa
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Evaluation of biofuel production integrated with existing CHP plants and the impacts on production planning of the system – A case study2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 252, artikel-id 113461Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The increasing atmospheric CO2 concentration has caused a transformative shift in global energy systems, which is contributing to an increased use of renewables. Sweden is among the countries trying to shift to a fossil-fuel-free system in all energy sectors. This paper addresses the fuel demand and supply in the transportation sector in the county of Västmanland in Sweden. A Mixed Integer Linear Programming optimization model is developed to minimize cost in the studied system. The model is further used to investigate the influence of three different scenarios on production planning of regional Combined Heat and Power (CHP) plants: (1) straw-based biofuel production integrated with existing CHP plants to fuel combustion engine vehicles, (2) use of electric vehicles, and (3) use of hybrid vehicles fueled by both electricity and bioethanol. Potential solar power generation from rooftop solar cells is also included in the model. The energy system in scenario 2 is found to have the highest overall system efficiency; however, a large amount of power needs to be imported to the system. Hybrid vehicles can potentially reduce the electricity import and CO2 emissions compared to the current situation. Electricity production from rooftop solar collectors could provide the energy needs of the vehicles during summer, while regionally produced straw-based bioethanol integrated with CHP plants can satisfy the fuel needs of the vehicles in winter. This approach could affect the production planning of CHP plants, result in less fuel use and increase the share of renewable resources in the regional transportation system. 

  • 148.
    Daraei, Mahsa
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Optimization of a regional energy system including CHP plants and local PV system and hydropower: Scenarios for the County of Västmanland in Sweden2019Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 230, s. 1111-1127Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Providing the energy needs of the cumulatively increasing population has become a challenge for the regional energy systems in the world. The most critical challenge is to supply enough energy in the forms of heat and power during the cold and warm periods of the year with the lowest production cost and minimum environmental impacts. A solution is to increase the green energy supply from renewable energy resources such as solar, wind power, and hydropower. In order to apply this solution in the real energy system, potentials for clean energy supply in an optimized manner should be evaluated. In this study, an optimization model is developed for a regional energy system in the central part of Sweden. The studied system consists of Combined Heat and Power (CHP)plants and heat water boilers together with renewable energy supply from rooftop Photo Voltaic (PV)- solar collectors and regional hydropower plants. The General Algebraic Modeling System (GAMS)is used to create the model based on the Mixed Integer Linear Programming (MILP)method. The goal is to evaluate the influence of local renewable energy systems on the production planning of CHP plants in a region. Two different scenarios are investigated based on the extremes in energy supply and demand concerning the increased use of Electrical Vehicles (EVs)and more application of Heat Pumps (HPs)in the system. The results show that installation of rooftop PV systems has the potential to reduce the electricity import to the region; however, it will at the same time reduce the operation time of the CHP plans during the summer period. With increased use of HPs for heating, the shut off time for CHP plants is further increased. Increase in electric passenger cars penetration in the system has no impacts on the production profiles of the plants. The regional electricity demand grows significantly by more utilization of EVs and increased application of heat pumps in the studied system. The high electricity demand will mainly be satisfied by importing electricity from outside the region together with low production from CHP plants and the power generated by the rooftop PV systems and regional hydropower. The developed optimization model with studied scenarios can be applied to other energy systems to increase the knowledge of production planning and feasibility of a fossil fuel free energy system.

  • 149.
    Daraei, Mahsa
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Evaluation of potential fossil fuel free energy system: Scenarios for optimization of a regional integrated system2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 964-970Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Population growth and urbanization have led to increases in energy demand and consequently, greenhouse gas emissions. Therefore, the availability of the fossil fuel as the main source of energy supply has been changed. Utilization of renewable resources including solar, wind, and hydropower together with distributed energy systems could eliminate the dependency on fossil fuel energy sources. In this paper, energy use and supply trends have been studied for the Counties of Västmanland and Södermanland in Sweden in order to develop a scenario for the regional energy system in 2030. The aim is to use the scenario for evaluation of the impacts of regional renewable energy resources on the production planning of CHP plants. The scenario shows that there is not enough potential for electricity production from renewable resources such as solar, wind, and hydropower to fulfill the estimated demand in 2030. Around 75% of electricity needs in Västmanland and 89% of power demands in Södermanland need to be met by imported electricity to these regions. Efficiency improvements and a more complex energy system integrating also with other energy resources like biomass, waste and industrial waste heat are necessary to develop a sustainable energy system.

  • 150.
    Daraei, Mahsa
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Potential biofuel production in a fossil fuel free transportation system: A scenario for the County of Västmanland in Sweden2019Ingår i: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, s. 1330-1336Konferensbidrag (Refereegranskat)
    Abstract [en]

    Air pollution and increased CO2 concentration in atmosphere and other energy related issues caused a transformative shift in energy system which contributes to increased utilization of renewables as alternative to generate green energy carriers. The potential of renewable resources in different region and potential energy conversion have been largely considered by many researcher in many countries. The energy conversion technologies to produce heat, electricity, and transportation fuels have made impressive technical advances. Sweden has also been challenging with mitigation of CO2 emission and trying to shift into a fossil fuel free system in all energy sectors. This paper deals with the current status of fuel demand and supply in the transport sector in a County in Sweden. A scenario for a fossil fuel free transport sector at a regional level is developed to investigate the potential biofuel production from regionally produced straw. The results and analysis indicate that the potential for cereal based bioethanol production in the region is sufficient to meet the biofuel demand of the County. Using the fallow land for cereal cultivation, it is feasible to shift into a fossil fuel free transportation system where all passenger cars are fueled by bioethanol. The results and finding from the current paper will be used to develop further study on optimization of local biofuel production integrated with CHP plants considering application of other feedstock such as municipal wastes.

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