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Publications (10 of 11) Show all publications
Daraei, M., Campana, P. E., Avelin, A. & Thorin, E. (2021). A multi-criteria analysis to assess the optimal flexibility pathway for regional energy systems with high share of renewables. In: : . Paper presented at International Conference on Applied Energy, ICAE 12th.
Open this publication in new window or tab >>A multi-criteria analysis to assess the optimal flexibility pathway for regional energy systems with high share of renewables
2021 (English)Conference paper, Oral presentation only (Refereed)
National Category
Energy Systems Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-54035 (URN)
Conference
International Conference on Applied Energy, ICAE 12th
Available from: 2021-04-29 Created: 2021-04-29 Last updated: 2023-09-25Bibliographically approved
Daraei, M., Campana, P. E. & Thorin, E. (2021). Corrigendum to “Power-to-hydrogen storage integrated with rooftop photovoltaic systems and combined heat and power plants”. [Appl. Energy 276 (2020) 115499] (Applied Energy (2020) 276, (S0306261920310114), (10.1016/j.apenergy.2020.115499)). Applied Energy, 281, Article ID 116079.
Open this publication in new window or tab >>Corrigendum to “Power-to-hydrogen storage integrated with rooftop photovoltaic systems and combined heat and power plants”. [Appl. Energy 276 (2020) 115499] (Applied Energy (2020) 276, (S0306261920310114), (10.1016/j.apenergy.2020.115499))
2021 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 281, article id 116079Article in journal, Editorial material (Other academic) Published
Abstract [en]

The authors regret that there is a typo mistake in Table 3 in the paper. The value of “Hydropower” in the table was incorrectly written 831 GWh; however, it shall be 83 GWh. The revised table is as follows: The authors would like to apologize for any inconvenience caused. 

Place, publisher, year, edition, pages
Elsevier Ltd, 2021
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-52385 (URN)10.1016/j.apenergy.2020.116079 (DOI)000591381100003 ()2-s2.0-85094599201 (Scopus ID)
Available from: 2020-11-10 Created: 2020-11-10 Last updated: 2021-02-17Bibliographically approved
Daraei, M., Campana, P. E., Avelin, A., Jurasz, J. & Thorin, E. (2021). Impacts of integrating pyrolysis with existing CHP plants and onsite renewable-based hydrogen supply on the system flexibility. Energy Conversion and Management, 43, Article ID 114407.
Open this publication in new window or tab >>Impacts of integrating pyrolysis with existing CHP plants and onsite renewable-based hydrogen supply on the system flexibility
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2021 (English)In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 43, article id 114407Article in journal (Other academic) Published
Abstract [en]

The share of renewable energy sources in the primary energy use is increasing worldwide. Given the intermittency of the energy supply from renewables, it is important to increase flexibility in the system to respond to the imbalances between energy demand and supply. Several flexibility options such as power storage and energy integration are currently in use, mostly at small scales. The increased energy supply from renewables and the flexibility solutions can influence the production planning of existing thermal energy conversion plants. In this study, integration of energy technologies including a hydrotreated pyrolysis oil production integrated with existing CHP plants is investigated as a flexibility solution. The system interacts with potential power generation from rooftop PV systems integrated with power-to-hydrogen storage. A cost-optimization model is developed using MILP method. The study focuses on the system flexibility and operational strategy of the existing CHP plants considering market trends, climate changes, and future energy developments with increased penetration of heat pumps and electric vehicles but less fossil fuels use. The results indicate that the suggested integrated system can increase the local energy supply by 33 GWh. Moreover, the power-to-hydrogen storage and onsite hydrogen use can increase the share of renewables in energy supply by 6%. Optimization of the developed scenarios for future energy-related changes indicates that the market trends could significantly reduce the performance of the system by 21% but increase the penetration of renewables in the system by 8%. Overall, scenario analysis shows the potential of using such a polygeneration system for flexible energy supply including existing CHP plants. 

National Category
Energy Engineering Energy Systems
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-54036 (URN)10.1016/j.enconman.2021.114407 (DOI)000679381500008 ()2-s2.0-85108584322 (Scopus ID)
Available from: 2021-04-29 Created: 2021-04-29 Last updated: 2022-11-25Bibliographically approved
Daraei, M. (2021). Production Planning of CHP plants in transition towards energy systems with high share of renewables. (Doctoral dissertation). Västerås: Mälardalen University
Open this publication in new window or tab >>Production Planning of CHP plants in transition towards energy systems with high share of renewables
2021 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The global energy system is undergoing a transformative change towards renewable energies. The share of Renewable Energy Sources (RES) and bioenergy in the world’s primary energy use has increased in the recent years. Based on the EU Roadmap 2050 energy plan, the share of renewables in final energy use in Europe will reach at least 55%, a 45% increase from its share today.

Due to the intermittent energy supply from renewables, their high penetration in energy systems can jeopardize the system flexibility, in terms of the balance between energy demand and supply. Lack of system flexibility could cause energy curtailments, increase system costs, or make renewables unreliable sources of energy. Moreover, the expansion of the renewable energy supply could influence the operational strategy of existing energy systems like Combined Heat and Power (CHP) plants. Therefore, the current study focuses on increasing system flexibility of a CHP-dominated regional energy system with increased renewable power supply. Two flexibility options, including a polygeneration strategy and large-scale energy storage using power-to-gas technology, were modelled. The system is then optimized using a Mixed Integer Linear Programming (MILP) method to investigate the production planning of CHP plants in a renewable-based energy system with higher level of flexibility. Different technical and market factors could influence the results of the optimization model, and thereby system flexibility. Thus, the study is carried out under various scenarios for better understanding of the future challenges regarding energy supply, market prices, and climate change.

The investigation provides an increased knowledge of production planning for the existing CHP plants with increased interaction with renewables. Based on the overall observations of this thesis, the proposed power storage system contributes to the increased system flexibility. However, the study suggests polygeneration and integration strategy as the optimal pathway to increase RES penetration and to support system flexibility, considering future energy developments and changes in energy demand and supply.

Place, publisher, year, edition, pages
Västerås: Mälardalen University, 2021
Series
Mälardalen University Press Dissertations, ISSN 1651-4238 ; 335
National Category
Energy Systems Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-54037 (URN)978-91-7485-507-4 (ISBN)
Public defence
2021-06-18, Delta + digitalt via Zoom, Mälardalens högskola, Västerås, 09:00 (English)
Opponent
Supervisors
Available from: 2021-04-29 Created: 2021-04-29 Last updated: 2021-07-01Bibliographically approved
Daraei, M., Campana, P. E. & Thorin, E. (2020). Power-to-hydrogen storage integrated with rooftop photovoltaic systems and combined heat and power plants. Applied Energy, 276, Article ID 115499.
Open this publication in new window or tab >>Power-to-hydrogen storage integrated with rooftop photovoltaic systems and combined heat and power plants
2020 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 276, article id 115499Article in journal (Refereed) Published
Abstract [en]

The growing share of intermittent renewable energy sources for power generation indicates an increasing demand for flexibility in the energy system. Energy storage technologies ensure a balance between demand and supply and increase the system flexibility. This study investigates increased application of renewable energy resources at a regional scale. Power-to-gas storage that interacts with a large-scale rooftop photovoltaic system is added to a regional energy system dominated by combined heat and power plants. The study addresses the influence of the storage system on the production planning of the combined heat and power plants and the system flexibility. The system is modeled and the product costs are optimized using the Mixed Integer Linear Programming method, as well as considering the effects on CO2 emissions and power import into the regional system. The optimization model is investigated by developing different scenarios for the capacity and cost of the storage system. The results indicate that the proposed storage system increases the system flexibility and can reduce power imports and the marginal emissions by around 53%, compared with the current energy system. There is a potential to convert a large amount of excess power to hydrogen and store it in the system. However, because of low efficiency, a fuel cell cannot significantly contribute to power regeneration from the stored hydrogen. Therefore, for about 70% of the year, the power is imported to the optimized system to compensate the power shortfalls rather than to use the fuel cell. 

Place, publisher, year, edition, pages
Oxford: Elsevier Ltd, 2020
Keywords
Flexibility, Hydrogen, Optimization, Power-to-gas, Production planning, Renewable energy sources, Cogeneration plants, Fuel cells, Hydrogen storage, Integer programming, Photovoltaic cells, Production control, Renewable energy resources, Energy storage technologies, Mixed integer linear programming, Optimization modeling, Regional energy systems, Renewable energy source, Rooftop photovoltaic systems, System flexibility, Electric power system interconnection, alternative energy, combined heat and power, energy resource, energy storage, fuel cell, photovoltaic system, power generation
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-49483 (URN)10.1016/j.apenergy.2020.115499 (DOI)000571786500002 ()2-s2.0-85088401042 (Scopus ID)
Available from: 2020-08-06 Created: 2020-08-06 Last updated: 2021-04-29Bibliographically approved
Daraei, M., Avelin, A., Dotzauer, E. & Thorin, E. (2019). Evaluation of biofuel production integrated with existing CHP plants and the impacts on production planning of the system – A case study. Applied Energy, 252, Article ID 113461.
Open this publication in new window or tab >>Evaluation of biofuel production integrated with existing CHP plants and the impacts on production planning of the system – A case study
2019 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 252, article id 113461Article in journal (Refereed) Published
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. 

Keywords
Electric vehicles, Energy systems, Mixed Integer Linear Programming, Optimization, Straw-based bioethanol, Transportation sector
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-44658 (URN)10.1016/j.apenergy.2019.113461 (DOI)000497968000059 ()2-s2.0-85067284871 (Scopus ID)
Available from: 2019-06-27 Created: 2019-06-27 Last updated: 2021-11-30Bibliographically approved
Daraei, M., Avelin, A. & Thorin, E. (2019). Optimization of a regional energy system including CHP plants and local PV system and hydropower: Scenarios for the County of Västmanland in Sweden. Journal of Cleaner Production, 230, 1111-1127
Open this publication in new window or tab >>Optimization of a regional energy system including CHP plants and local PV system and hydropower: Scenarios for the County of Västmanland in Sweden
2019 (English)In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 230, p. 1111-1127Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
Elsevier Ltd, 2019
Keywords
Electrical vehicle, Heat pump, Optimization, Production planning, Renewable energy resource, Algebra, Cogeneration plants, Economics, Electric power utilization, Energy policy, Environmental impact, Fossil fuels, Free energy, Heat pump systems, Hydroelectric power, Hydroelectric power plants, Integer programming, Planning, Power generation, Production control, Pumps, Renewable energy resources, Wind power, Clean energy supplies, Combined heat and power, Electrical vehicles, Heat pumps, Mixed-integer linear programming, Optimization modeling, Regional energy systems, Electric power system interconnection
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-43876 (URN)10.1016/j.jclepro.2019.05.086 (DOI)000474676300098 ()2-s2.0-85065879762 (Scopus ID)
Available from: 2019-06-11 Created: 2019-06-11 Last updated: 2021-11-30Bibliographically approved
Daraei, M., Thorin, E., Avelin, A. & Dotzauer, E. (2019). Potential biofuel production in a fossil fuel free transportation system: A scenario for the County of Västmanland in Sweden. In: Energy Procedia: . Paper presented at 10th International Conference on Applied Energy (ICAE2018), 22-25 August 2018, Hong Kong, China (pp. 1330-1336). Elsevier Ltd, 158
Open this publication in new window or tab >>Potential biofuel production in a fossil fuel free transportation system: A scenario for the County of Västmanland in Sweden
2019 (English)In: Energy Procedia, Elsevier Ltd , 2019, Vol. 158, p. 1330-1336Conference paper, Published paper (Refereed)
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.

Place, publisher, year, edition, pages
Elsevier Ltd, 2019
Keywords
Bioethanol, Energy system, Straw, Transport sector
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:mdh:diva-43132 (URN)10.1016/j.egypro.2019.01.327 (DOI)000471031701107 ()2-s2.0-85063892971 (Scopus ID)
Conference
10th International Conference on Applied Energy (ICAE2018), 22-25 August 2018, Hong Kong, China
Available from: 2019-04-18 Created: 2019-04-18 Last updated: 2021-11-30Bibliographically approved
Daraei, M., Thorin, E., Avelin, A. & Dotzauer, E. (2019). Potentials for increased application of renewables in the transportation system: A case study for Södermanland County, Sweden. In: Energy Procedia: . Paper presented at Applied Energy Symposium and Forum, Renewable Energy Integration with Mini/Microgrids, REM 2018, 29–30 September 2018, Rhodes, Greece (pp. 267-273). Elsevier Ltd
Open this publication in new window or tab >>Potentials for increased application of renewables in the transportation system: A case study for Södermanland County, Sweden
2019 (English)In: Energy Procedia, Elsevier Ltd , 2019, p. 267-273Conference paper, Published paper (Refereed)
Abstract [en]

In this study, possible alternations in a regional transport sector are assessed to increase the use of renewable resources. Three scenarios are developed aimed to investigate different alternatives including potential straw-based bioethanol supply to fuel regional cars with combustion engines, more use of Electrical Vehicles (EVs) with use of potential power from solar energy, and the feasibility of application of hybrid cars fueled with electricity and bioethanol. The evaluation considers the reduction in CO 2 emissions and increased balance in energy demand and supply. Results of the study indicate that application of hybrid vehicles with bioethanol-fueled engines and electrical motors could potentially reduce the CO 2 emissions compared with other proposed approaches in the studied scenarios. At the same time, there would be a balance in the system, so that, the bioethanol production from the available cereal straw in the region can meet the energy demand of suggested hybrid cars in wintertime. While, the energy supply from solar cells installed on the rooftop of the buildings can cover the electricity need of the motor during summer. This approach will also result in increased use of renewables in the transportation system.

Place, publisher, year, edition, pages
Elsevier Ltd, 2019
Keywords
EVs, Hybrid, Renewable resources, Solar cells, Straw-based bioethanol
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:mdh:diva-43133 (URN)10.1016/j.egypro.2018.12.061 (DOI)000471291100043 ()2-s2.0-85063808717 (Scopus ID)
Conference
Applied Energy Symposium and Forum, Renewable Energy Integration with Mini/Microgrids, REM 2018, 29–30 September 2018, Rhodes, Greece
Available from: 2019-04-18 Created: 2019-04-18 Last updated: 2021-11-30Bibliographically approved
Daraei, M. (2019). Production planning of CHP plants integrated with bioethanol production and local renewables. (Licentiate dissertation). Västerås: Mälardalen University
Open this publication in new window or tab >>Production planning of CHP plants integrated with bioethanol production and local renewables
2019 (English)Licentiate thesis, comprehensive summary (Other academic)
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.

Place, publisher, year, edition, pages
Västerås: Mälardalen University, 2019
Series
Mälardalen University Press Licentiate Theses, ISSN 1651-9256 ; 285
Keywords
CHP, Energy systems, Optimization, Polygeneration, Production planning, Renewable resources
National Category
Energy Engineering Energy Systems
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-45801 (URN)978-91-7485-445-9 (ISBN)
Presentation
2019-12-16, Beta, Mälardalen University, Västerås, 09:15 (English)
Opponent
Supervisors
Projects
SYDPOL-System Development for Power Plant Production Planning and Optimal Operations
Available from: 2019-10-23 Created: 2019-10-23 Last updated: 2019-11-14Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-7576-760x

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