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Integration of Renewables in Power Systems by Multi-Energy System Interaction

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "F: Electrical Engineering".

Deadline for manuscript submissions: closed (30 June 2020) | Viewed by 48179

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Guest Editor
Department of Energy Technology, Aalborg University, Aalborg, Denmark
Interests: multienergy systems; renewables; storages; electrification of transport and heating sector; hierarchical control; demand response; grid flexibility; hosting capacity; power flow; protection in distribution grids
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Guest Editor
Department of Energy Engineering, Aalborg University, Aalborg, Denmark
Interests: smart grids; multicarrier energy systems; grid integration of distributed energy systems; electric distribution systems; demand response

Special Issue Information

Dear Colleagues,

This Special Issue will focus on the interaction between different energy vectors that is between electrical, thermal, gas, and transportation systems, with the purpose of optimizing the future energy system. More and more renewable energy is integrated into the electrical system, and to optimize the usage and ensure that full production can be hosted and utilized, the power system has to be controlled in a more flexible manner—as an example, using excess electricity in the thermal system, using heat pumps or electrical boilers, and storing energy as thermal energy in storage tanks or in the district heating system. Another solution is to use and store electrical energy in the batteries of electrical vehicles, either to be used for transport or to be fed back to the power system again (V2G principle). The gas system can also be involved, using electrolyzers and storing hydrogen. In order not to overload the electrical distribution grid, the new large loads have to be controlled using demand response, perchance through a hierarchal control set-up where some controls are dependent on price signals from the spot and balancing market, but also where local real-time control and coordination are performed based on local voltage or frequency measurements where grid hosting limits are not violated. We welcome contributions on multienergy systems to explore the different possibilities for the future smart energy system with a huge interaction among the different energy systems. The topics of interest include, but are not limited to:

  • Modeling, optimization, and analysis of multienergy systems;
  • Planning, operation, and control;
  • Interaction and coupling between different energy supply systems and networks;
  • Flexible demand and energy storages;
  • Energy efficiency and management;
  • Reliability and security of multienergy systems;
  • Cyberphysical systems, information and communication infrastructure, and data analytics;
  • Market, social, regulatory frameworks and policies for multienergy systems.

Prof. Dr. Birgitte Bak-Jensen
Assoc. Prof. Dr. Jayakrishnan Radhakrishna Pillai
Guest Editors

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Keywords

  • multienergy systems
  • renewable energy
  • energy storages
  • flexible demand
  • electrification of transport and heating sector
  • hierarchical control
  • demand response
  • grid flexibility
  • hosting capacity

Published Papers (16 papers)

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Research

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22 pages, 2707 KiB  
Article
Technical Approaches and Institutional Alignment to 100% Renewable Energy System Transition of Madeira Island—Electrification, Smart Energy and the Required Flexible Market Conditions
by Hannah Mareike Marczinkowski and Luísa Barros
Energies 2020, 13(17), 4434; https://0-doi-org.brum.beds.ac.uk/10.3390/en13174434 - 27 Aug 2020
Cited by 18 | Viewed by 2751
Abstract
The integration of renewable energy (RE) in energy systems can be approached in many ways depending on local possibilities. Evaluating this in the limited context of islands, this paper presents a multi-energy system transition to a 100% RE share in a two-folded technical [...] Read more.
The integration of renewable energy (RE) in energy systems can be approached in many ways depending on local possibilities. Evaluating this in the limited context of islands, this paper presents a multi-energy system transition to a 100% RE share in a two-folded technical analysis. The case study of Madeira Island using the EnergyPLAN modeling tool is used to show strengths and weaknesses of, on the one hand, electrifying all transport and heating demands on an island, while remaining demands are supplied with biomass, and, on the other hand, additional smart charging, vehicle-to-grid, thermal collectors and storages, as well as electrofuel production and storages. Technical results indicate the potentials and advantages of the second approach with 50% less biomass and no curtailment at 1–3% higher costs, compared to the first one with 7% of production curtailed. The technical analysis is supported by the institutional analysis that highlights the balancing needs through additional flexibility and interaction in the energy system. For maximum flexibility, of both demand and grid, and successful implementation of 100% RE, investment incentives and dynamic tariffs are recommended entailing more dynamic consumer involvement and strategic energy planning. Full article
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31 pages, 2982 KiB  
Article
A GIS-Based Planning Approach for Urban Power and Natural Gas Distribution Grids with Different Heat Pump Scenarios
by Jolando M. Kisse, Martin Braun, Simon Letzgus and Tanja M. Kneiske
Energies 2020, 13(16), 4052; https://0-doi-org.brum.beds.ac.uk/10.3390/en13164052 - 05 Aug 2020
Cited by 10 | Viewed by 4487
Abstract
Next to building insulation, heat pumps driven by electrical compressors (eHPs) or by gas engines (geHPs) can be used to reduce primary energy demand for heating. They come with different investment requirements, operating costs and emissions caused. In addition, they affect both the [...] Read more.
Next to building insulation, heat pumps driven by electrical compressors (eHPs) or by gas engines (geHPs) can be used to reduce primary energy demand for heating. They come with different investment requirements, operating costs and emissions caused. In addition, they affect both the power and gas grids, which necessitates the assessment of both infrastructures regarding grid expansion planning. To calculate costs and CO2 emissions, 2000 electrical load profiles and 180 different heat demand profiles for single-family homes were simulated and heat pump models were applied. In a case study for a neighborhood energy model, the load profiles were assigned to buildings in an example town using public data on locations, building age and energetic refurbishment variants. In addition, the town’s gas distribution network and low voltage grid were modeled. Power and gas flows were simulated and costs for required grid extensions were calculated for 11% and 16% heat pump penetration. It was found that eHPs have the highest energy costs but will also have the lowest CO2 emissions by 2030 and 2050. For the investigated case, power grid investments of 11,800 euros/year are relatively low compared to gas grid connection costs of 70,400 euros/year. If eHPs and geHPs are combined, a slight reduction of overall costs is possible, but emissions would rise strongly compared to the all-electric case. Full article
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23 pages, 6882 KiB  
Article
Coordinated Flexibility Scheduling for Urban Integrated Heat and Power Systems by Considering the Temperature Dynamics of Heating Network
by Wei Wei, Yaping Shi, Kai Hou, Lei Guo, Linyu Wang, Hongjie Jia, Jianzhong Wu and Chong Tong
Energies 2020, 13(12), 3273; https://0-doi-org.brum.beds.ac.uk/10.3390/en13123273 - 24 Jun 2020
Cited by 6 | Viewed by 2382
Abstract
The coordinated heat-electricity dispatch of the urban integrated energy system (UIES) helps to improve the system flexibility, thereby overcoming the adverse effects caused by the random fluctuations of renewable energy (RE) and promoting the penetration of RE. Among them, the dynamic characteristics of [...] Read more.
The coordinated heat-electricity dispatch of the urban integrated energy system (UIES) helps to improve the system flexibility, thereby overcoming the adverse effects caused by the random fluctuations of renewable energy (RE) and promoting the penetration of RE. Among them, the dynamic characteristics of the urban heat network (UHN) are important features that need to be considered for the operating scheduling of the UIES. This paper aims to establish a flexibility scheduling model for UIES based on the dynamic characteristics of the UHN. First, the typical structure and key equipment model of the urban integrated heat and power system (UIHPS) with the dynamic characteristics of the UHN is proposed. Then, the definition and model of the UIHPS flexibility and the assessment index of the flexibility are developed. Moreover, a flexibility scheduling model for a UIHPS that considers the dynamic characteristics of a UHN is established. Finally, the validity of the proposed model is validated by case studies, and the applicability of flexibility scheduling and the effect of heat load (HL) are analyzed. Full article
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14 pages, 2150 KiB  
Article
Reactive Power Control Method for Enhancing the Transient Stability Total Transfer Capability of Transmission Lines for a System with Large-Scale Renewable Energy Sources
by Yuwei Zhang, Wenying Liu, Fangyu Wang, Yaoxiang Zhang and Yalou Li
Energies 2020, 13(12), 3154; https://0-doi-org.brum.beds.ac.uk/10.3390/en13123154 - 17 Jun 2020
Cited by 6 | Viewed by 1983
Abstract
With the increased proportion of intermittent renewable energy sources (RES) integrated into the sending-end, the total transfer capability of transmission lines is not sufficient during the peak periods of renewable primary energy (e.g., the wind force), causing severe RES power curtailment. The total [...] Read more.
With the increased proportion of intermittent renewable energy sources (RES) integrated into the sending-end, the total transfer capability of transmission lines is not sufficient during the peak periods of renewable primary energy (e.g., the wind force), causing severe RES power curtailment. The total transfer capability of transmission lines is generally restricted by the transient stability total transfer capability (TSTTC). This paper presents a reactive power control method to enhance the TSTTC of transmission lines. The key is to obtain the sensitivity between TSTTC and reactive power, while the Thevenin equivalent voltage is the link connecting TSTTC and reactive power. The Thevenin theorem states that an active circuit between two load terminals can be considered as an individual voltage source. The voltage of this source would be open-circuit voltage across the terminals, and the internal impedance of the source is the equivalent impedance of the circuit across the terminals. The Thevenin voltage used in Thevenin’s theorem is an ideal voltage source equal to the open-circuit voltage at the terminals. Thus, the sensitivities between TSTTC and the Thevenin equivalent voltages of the sending-end and receiving-end were firstly derived using the equal area criterion. Secondly, the sensitivity between the Thevenin equivalent voltage and reactive power was derived using the total differentiation method. By connecting the above sensitivities together with the relevant parameters calculated from Thevenin equivalent parameter identification and power flow equation, the sensitivity between TSTTC and reactive power was obtained, which was used as the control priority in the proposed reactive power control method. At last, the method was applied to the Gansu Province Power Grid in China to demonstrate its effectiveness, and the accuracy of the sensitivity between TSTTC and reactive power was verified. Full article
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15 pages, 726 KiB  
Article
Maximizing Solar PV Dissemination under Differential Subsidy Policy across Regions
by Jeongmeen Suh and Sung-Guk Yoon
Energies 2020, 13(11), 2763; https://0-doi-org.brum.beds.ac.uk/10.3390/en13112763 - 01 Jun 2020
Cited by 5 | Viewed by 1850
Abstract
This study investigates the effect of a renewable energy dissemination policy on investment decisions regarding solar photovoltaic (PV) installation. We present a theoretical model and conduct a simulation analysis to estimate the total capacity of solar PV generators according to a given subsidy [...] Read more.
This study investigates the effect of a renewable energy dissemination policy on investment decisions regarding solar photovoltaic (PV) installation. We present a theoretical model and conduct a simulation analysis to estimate the total capacity of solar PV generators according to a given subsidy policy. We show how the capacity maximizing subsidy policy depends on the total amount of subsidy budget, interest rate, the expected amount of solar resource and land price in each region. We particularly focus on the improvements of solar PV capacities under the same subsidy budget when the subsidy policy is changed from uniform (equal for all regions) to differential (varying over regional characteristics). This improvement is shown through a case study using Korean data. Full article
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35 pages, 2306 KiB  
Article
Flexibility Assessment of Multi-Energy Residential and Commercial Buildings
by António Coelho, Filipe Soares and João Peças Lopes
Energies 2020, 13(11), 2704; https://0-doi-org.brum.beds.ac.uk/10.3390/en13112704 - 28 May 2020
Cited by 1 | Viewed by 1782
Abstract
With the growing concern about decreasing CO 2 emissions, renewable energy sources are being vastly integrated in the energy systems worldwide. This will bring new challenges to the network operators, which will need to find sources of flexibility to cope with the variable-output [...] Read more.
With the growing concern about decreasing CO 2 emissions, renewable energy sources are being vastly integrated in the energy systems worldwide. This will bring new challenges to the network operators, which will need to find sources of flexibility to cope with the variable-output nature of these technologies. Demand response and multi-energy systems are being widely studied and considered as a promising solution to mitigate possible problems that may occur in the energy systems due to the large-scale integration of renewables. In this work, an optimal model to manage the resources and loads within residential and commercial buildings was developed, considering consumers preferences, electrical network restrictions and CO 2 emissions. The flexibility that these buildings can provide was analyzed and quantified. Additionally, it was shown how this model can be used to solve technical problems in electrical networks, comparing the performance of two scenarios of flexibility provision: flexibility obtained only from electrical loads vs. flexibility obtained from multi-energy loads. It was proved that multi-energy systems bring more options of flexibility, as they can rely on non-electrical resources to supply the same energy needs and thus relieve the electrical network. It was also found that commercial buildings can offer more flexibility during the day, while residential buildings can offer more during the morning and evening. Nonetheless, Multi-Energy System (MES) buildings end up having higher CO 2 emissions due to a higher consumption of natural gas. Full article
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19 pages, 3412 KiB  
Article
An Optimal Day-Ahead Thermal Generation Scheduling Method to Enhance Total Transfer Capability for the Sending-Side System with Large-Scale Wind Power Integration
by Yuwei Zhang, Wenying Liu, Yue Huan, Qiang Zhou and Ningbo Wang
Energies 2020, 13(9), 2375; https://0-doi-org.brum.beds.ac.uk/10.3390/en13092375 - 09 May 2020
Cited by 3 | Viewed by 1657
Abstract
The rapidly increasing penetration of wind power into sending-side systems makes the wind power curtailment problem more severe. Enhancing the total transfer capability (TTC) of the transmission channel allows more wind power to be delivered to the load center; therefore, the curtailed wind [...] Read more.
The rapidly increasing penetration of wind power into sending-side systems makes the wind power curtailment problem more severe. Enhancing the total transfer capability (TTC) of the transmission channel allows more wind power to be delivered to the load center; therefore, the curtailed wind power can be reduced. In this paper, a new method is proposed to enhance TTC, which works by optimizing the day-ahead thermal generation schedules. First, the impact of thermal generation plant/unit commitment on TTC is analyzed. Based on this, the day-ahead thermal generation scheduling rules to enhance TTC are proposed herein, and the corresponding optimization models are established and solved. Then, the optimal day-ahead thermal generation scheduling method to enhance TTC is formed. The proposed method was validated on the large-scale wind power base sending-side system in Gansu Province in China; the results indicate that the proposed method can significantly enhance TTC, and therefore, reduce the curtailed wind power. Full article
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23 pages, 3839 KiB  
Article
Cost-Effectiveness of Carbon Emission Abatement Strategies for a Local Multi-Energy System—A Case Study of Chalmers University of Technology Campus
by Nima Mirzaei Alavijeh, David Steen, Zack Norwood, Le Anh Tuan and Christos Agathokleous
Energies 2020, 13(7), 1626; https://0-doi-org.brum.beds.ac.uk/10.3390/en13071626 - 02 Apr 2020
Cited by 12 | Viewed by 2664
Abstract
This paper investigates the cost-effectiveness of operation strategies which can be used to abate CO 2 emissions in a local multi-energy system. A case study is carried out using data from a real energy system that integrates district heating, district cooling, and electricity [...] Read more.
This paper investigates the cost-effectiveness of operation strategies which can be used to abate CO 2 emissions in a local multi-energy system. A case study is carried out using data from a real energy system that integrates district heating, district cooling, and electricity networks at Chalmers University of Technology. Operation strategies are developed using a mixed integer linear programming multi-objective optimization model with a short foresight rolling horizon and a year of data. The cost-effectiveness of different strategies is evaluated across different carbon prices. The results provide insights into developing abatement strategies for local multi-energy systems that could be used by utilities, building owners, and authorities. The optimized abatement strategies include: increased usage of biomass boilers, substitution of district heating and absorption chillers with heat pumps, and higher utilization of storage units. The results show that, by utilizing all the strategies, a 20.8% emission reduction can be achieved with a 2.2% cost increase for the campus area. The emission abatement cost of all strategies is 36.6–100.2 (€/tCO 2 ), which is aligned with estimated carbon prices if the Paris agreement target is to be achieved. It is higher, however, than average European Emission Trading System prices and Sweden’s carbon tax in 2019. Full article
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19 pages, 4738 KiB  
Article
Integration of Hydrogen into Multi-Energy Systems Optimisation
by Peng Fu, Danny Pudjianto, Xi Zhang and Goran Strbac
Energies 2020, 13(7), 1606; https://0-doi-org.brum.beds.ac.uk/10.3390/en13071606 - 01 Apr 2020
Cited by 22 | Viewed by 4304
Abstract
Hydrogen presents an attractive option to decarbonise the present energy system. Hydrogen can extend the usage of the existing gas infrastructure with low-cost energy storability and flexibility. Excess electricity generated by renewables can be converted into hydrogen. In this paper, a novel multi-energy [...] Read more.
Hydrogen presents an attractive option to decarbonise the present energy system. Hydrogen can extend the usage of the existing gas infrastructure with low-cost energy storability and flexibility. Excess electricity generated by renewables can be converted into hydrogen. In this paper, a novel multi-energy systems optimisation model was proposed to maximise investment and operating synergy in the electricity, heating, and transport sectors, considering the integration of a hydrogen system to minimise the overall costs. The model considers two hydrogen production processes: (i) gas-to-gas (G2G) with carbon capture and storage (CCS), and (ii) power-to-gas (P2G). The proposed model was applied in a future Great Britain (GB) system. Through a comparison with the system without hydrogen, the results showed that the G2G process could reduce £3.9 bn/year, and that the P2G process could bring £2.1 bn/year in cost-savings under a 30 Mt carbon target. The results also demonstrate the system implications of the two hydrogen production processes on the investment and operation of other energy sectors. The G2G process can reduce the total power generation capacity from 71 GW to 53 GW, and the P2G process can promote the integration of wind power from 83 GW to 130 GW under a 30 Mt carbon target. The results also demonstrate the changes in the heating strategies driven by the different hydrogen production processes. Full article
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18 pages, 2894 KiB  
Article
Multi-Time Scale Optimization Scheduling Strategy for Combined Heat and Power System Based on Scenario Method
by Yunhai Zhou, Shengkai Guo, Fei Xu, Dai Cui, Weichun Ge, Xiaodong Chen and Bo Gu
Energies 2020, 13(7), 1599; https://0-doi-org.brum.beds.ac.uk/10.3390/en13071599 - 01 Apr 2020
Cited by 7 | Viewed by 1723
Abstract
The wind–heat conflict and wind power uncertainty are the main factors leading to the phenomenon of wind curtailment during the heating period in the northern region of China. In this paper, a multi-time scale optimal scheduling strategy for combined heat and power system [...] Read more.
The wind–heat conflict and wind power uncertainty are the main factors leading to the phenomenon of wind curtailment during the heating period in the northern region of China. In this paper, a multi-time scale optimal scheduling strategy for combined heat and power system is proposed. Considering the temporal dependence of wind power fluctuation, the intra-day wind power scenario generation method is put forward, and both day-ahead and intra-day optimization scheduling models based on the scenario method are established to maximize the system’s revenue. The case analyzes the impacts of the initial heat storage capacity of a heat storage device and different scheduling strategies on system revenue. It is verified that the scheduling strategy can better adapt to wind power uncertainty and improve the absorption capacity of wind power, while ensuring the safety and economical efficiency of system operation. Full article
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17 pages, 3395 KiB  
Article
Small-Signal Stability Analysis of Photovoltaic-Hydro Integrated Systems on Ultra-Low Frequency Oscillation
by Sijia Wang, Xiangyu Wu, Gang Chen and Yin Xu
Energies 2020, 13(4), 1012; https://0-doi-org.brum.beds.ac.uk/10.3390/en13041012 - 24 Feb 2020
Cited by 13 | Viewed by 2817
Abstract
In recent years, ultralow-frequency oscillation has repeatedly occurred in asynchronously connected regional power systems and brought serious threats to the operation of power grids. This phenomenon is mainly caused by hydropower units because of the water hammer effect of turbines and the inappropriate [...] Read more.
In recent years, ultralow-frequency oscillation has repeatedly occurred in asynchronously connected regional power systems and brought serious threats to the operation of power grids. This phenomenon is mainly caused by hydropower units because of the water hammer effect of turbines and the inappropriate Proportional-Integral-Derivative (PID) parameters of governors. In practice, hydropower and solar power are often combined to form an integrated photovoltaic (PV)-hydro system to realize complementary renewable power generation. This paper studies ultralow-frequency oscillations in integrated PV-hydro systems and analyzes the impacts of PV generation on ultralow-frequency oscillation modes. Firstly, the negative damping problem of hydro turbines and governors in the ultralow-frequency band was analyzed through the damping torque analysis. Subsequently, in order to analyze the impact of PV generation, a small-signal dynamic model of the integrated PV-hydro system was established, considering a detailed dynamic model of PV generation. Based on the small-signal dynamic model, a two-zone and four-machine system and an actual integrated PV-hydro system were selected to analyze the influence of PV generation on ultralow-frequency oscillation modes under different scenarios of PV output powers and locations. The analysis results showed that PV dynamics do not participate in ultralow-frequency oscillation modes and the changes of PV generation to power flows do not cause obvious changes in ultralow-frequency oscillation mode. Ultra-low frequency oscillations are mainly affected by sources participating in the frequency adjustment of systems. Full article
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24 pages, 4522 KiB  
Article
Medium- and Long-Term Integrated Demand Response of Integrated Energy System Based on System Dynamics
by Shuhui Ren, Xun Dou, Zhen Wang, Jun Wang and Xiangyan Wang
Energies 2020, 13(3), 710; https://0-doi-org.brum.beds.ac.uk/10.3390/en13030710 - 06 Feb 2020
Cited by 14 | Viewed by 2783
Abstract
For the integrated energy system of coupling electrical, cool and heat energy and gas and other forms of energy, the medium- and long-term integrated demand response of flexible load, energy storage and electric vehicles and other demand side resources is studied. It is [...] Read more.
For the integrated energy system of coupling electrical, cool and heat energy and gas and other forms of energy, the medium- and long-term integrated demand response of flexible load, energy storage and electric vehicles and other demand side resources is studied. It is helpful to mine the potentials of demand response of various energy sources in the medium- and long-term, stimulate the flexibility of integrated energy system, and improve the efficiency of energy utilization. Firstly, based on system dynamics, the response mode of demand response resources is analyzed from different time dimensions, and the long-term, medium-term and short-term behaviors of users participating in integrated demand response are considered comprehensively. An integrated demand response model based on medium-and long-term time dimension is established. Then the integrated demand response model of integrated energy system scheduling and flexible load, energy storage and electric vehicles as the main participants is established to simulate the response income of users participating in the integrated demand response project, and to provide data sources for the medium- and long-term integrated demand response system dynamics model. Finally, an example is given to analyze the differences in response behaviors of flexible load, energy storage and electric vehicle users in different time dimensions under the conditions of policy subsidy, regional location and user energy preferences in different stages of the integrated energy system. Full article
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21 pages, 3207 KiB  
Article
Flexibility from Electric Boiler and Thermal Storage for Multi Energy System Interaction
by Rakesh Sinha, Birgitte Bak-Jensen, Jayakrishnan Radhakrishna Pillai and Hamidreza Zareipour
Energies 2020, 13(1), 98; https://0-doi-org.brum.beds.ac.uk/10.3390/en13010098 - 24 Dec 2019
Cited by 15 | Viewed by 4129
Abstract
Active use of heat accumulators in the thermal system has the potential for achieving flexibility in district heating with the power to heat (P2H) units, such as electric boilers (EB) and heat pumps. Thermal storage tanks can decouple demand and generation, enhancing accommodation [...] Read more.
Active use of heat accumulators in the thermal system has the potential for achieving flexibility in district heating with the power to heat (P2H) units, such as electric boilers (EB) and heat pumps. Thermal storage tanks can decouple demand and generation, enhancing accommodation of sustainable energy sources such as solar and wind. The overview of flexibility, using EB and storage, supported by investigating the nature of thermal demand in a Danish residential area, is presented in this paper. Based on the analysis, curve-fitting tools, such as neural net and similar day method, are trained to estimate the residential thermal demand. Utilizing the estimated demand and hourly market spot price of electricity, the operation of the EB is scheduled for storing and fulfilling demand and minimizing energy cost simultaneously. This demonstrates flexibility and controlling the EB integrated into a multi-energy system framework. Results show that the curve fitting tool is effectively suitable to acknowledge thermal demands of residential area based on the environmental factor as well as user behaviour. The thermal storage has the capability of operating as a flexible load to support P2H system as well as minimize the effect of estimation error in fulfilling actual thermal demand simultaneously. Full article
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16 pages, 3324 KiB  
Article
Research on Double-Layer Optimal Scheduling Model of Integrated Energy Park Based on Non-Cooperative Game
by Feifan Chen, Haifeng Liang, Yajing Gao, Yongchun Yang and Yuxuan Chen
Energies 2019, 12(16), 3164; https://0-doi-org.brum.beds.ac.uk/10.3390/en12163164 - 16 Aug 2019
Cited by 14 | Viewed by 2064
Abstract
As the realization form of integrated energy system, integrated energy park is the key research object in the field of energy. Actual integrated energy parks are often partitioned internally. In order to take into account the interests of each zone in the optimal [...] Read more.
As the realization form of integrated energy system, integrated energy park is the key research object in the field of energy. Actual integrated energy parks are often partitioned internally. In order to take into account the interests of each zone in the optimal scheduling of integrated energy parks, a double-layer optimal scheduling model of integrated energy parks based on non-cooperative game theory is proposed. First, according to the operation of the integrated energy park, the output and cost model of the park is established. Second, with the minimum daily cost as the upper layer objective and the highest energy efficiency of the cogeneration system as the lower layer objective, a double-layer optimal scheduling model is established. Then based on non-cooperative game, the optimal operation strategy of each zone is obtained through the game among all the zones. An integrated energy park is taken as an example, the results show that the proposed model can make zones adjust their operation strategies more reasonably, thus helping to reduce the cost of the park and improve energy efficiency. Full article
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17 pages, 4601 KiB  
Article
Optimal Low-Carbon Economic Environmental Dispatch of Hybrid Electricity-Natural Gas Energy Systems Considering P2G
by Jing Liu, Wei Sun and Gareth P. Harrison
Energies 2019, 12(7), 1355; https://0-doi-org.brum.beds.ac.uk/10.3390/en12071355 - 09 Apr 2019
Cited by 24 | Viewed by 4088
Abstract
Power to gas facilities (P2G) could absorb excess renewable energy that would otherwise be curtailed due to electricity network constraints by converting it to methane (synthetic natural gas). The produced synthetic natural gas can power gas turbines and realize bidirectional energy flow between [...] Read more.
Power to gas facilities (P2G) could absorb excess renewable energy that would otherwise be curtailed due to electricity network constraints by converting it to methane (synthetic natural gas). The produced synthetic natural gas can power gas turbines and realize bidirectional energy flow between power and natural-gas systems. P2G, therefore, has significant potential for unlocking inherent flexibility in the integrated system, but also poses new challenges of increased system complexity. A coordinated operation strategy that manages power and natural-gas network constraints together is essential to address such challenges. In this paper, a novel low-carbon economic environmental dispatch strategy is presented considering all the constraints in both systems. The multi-objective black-hole particle swarm optimization algorithm (MOBHPSO) is adopted. In addition to P2G, a gas demand management strategy is proposed to support gas flow balance. A new solving approach that combines the effective redundancy method, trust region method, and Levenberg-Marquardt method is proposed to address the complex coupled constraints. Case studies that use an integrated IEEE 39-bus power and Belgian high-calorific 20-node gas system demonstrate the effectiveness and scalability of the proposed model and optimization method. The analysis of dispatch results illustrates the benefit of P2G for the wind power accommodation, and low-carbon, economic, and environmental improvement of integrated system operation. Full article
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Review

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22 pages, 1198 KiB  
Review
Applications of Triple Active Bridge Converter for Future Grid and Integrated Energy Systems
by Van-Long Pham and Keiji Wada
Energies 2020, 13(7), 1577; https://0-doi-org.brum.beds.ac.uk/10.3390/en13071577 - 01 Apr 2020
Cited by 18 | Viewed by 5127
Abstract
Renewable energy systems and electric vehicles (EVs) are receiving much attention in industrial and scholarly communities owing to their roles in reducing pollutant emissions. Integrated energy systems (IES), which connect different types of renewable energies and storages, have become common in many applications, [...] Read more.
Renewable energy systems and electric vehicles (EVs) are receiving much attention in industrial and scholarly communities owing to their roles in reducing pollutant emissions. Integrated energy systems (IES), which connect different types of renewable energies and storages, have become common in many applications, such as the grid-connected photovoltaic (PV) and battery systems, fuel cells and battery/supercapacitor in EVs. The advantages of all energy sources are maximized by utilizing connection and control strategies. Because many storage systems and household loads are mainly direct current (DC) types, the DC grid has considerable potential for increasing the efficiency of distribution grids in the future. In IES and future DC grid systems, the triple active bridge (TAB) converter is an isolated bidirectional DC-DC converter that has many advantages as a core circuit. Therefore, this paper reviews the characteristics of the TAB converter in current applications and suggests next-generation applications. First, the characteristics and operation modes of the TAB converter are introduced. An overview of all current applications of the TAB converter is then presented. The advantages and challenges of the TAB converter in each application are discussed. Thereafter, the potential future applications of the TAB converter with an adaptable power transmission design are presented. Full article
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