Multi Vector Energy Distribution System Modelling and Optimisation with Integrated Demand Side Response

Lead Research Organisation: University of Bath
Department Name: Electronic and Electrical Engineering

Abstract

Electricity and natural gas networks, as two major energy transport infrastructure, have traditionally been planned and operated independently from each other. Electricity generation was dominated by coal, oil and nuclear power stations prior to 1990, when the "dash for gas" brought a significant number of gas-fired power stations into the generation mix. These geographically dispersed large power stations have created a loose link between natural gas and electricity networks at the energy source. As the pace of decarbonising our electricity section accelerates, the two energy networks will progressively become more closely linked by end users, driven by the electrification of heat and major efficiency improvements. This presents critical new challenges to the traditional network modelling, operation and optimisations, in particular as they were developed independently for natural gas and electricity networks. The traditional methods do not take into account of the substantial rise in the interaction between the two networks, i.e. how a change in gas demand/resource might impact the demand/generation of the electrical system and vice versa.

The vision of this research is to develop a statistical model for combined gas and electricity systems at the distribution level that can efficiently simulate the interactions across the energy vector under severe uncertainties. The developed model will then be fed to the novel optimal operation strategies to manage the two systems for encouraging increased use of renewables and infrastructure and promoting customer interaction with the systems. This fellowship will address this vision by developing highly efficient network sampling methodologies, multi-vector probabilistic energy flow and optimisation tools that will transform the modelling and analysis of highly integrated systems. These new developments will: i) enable detailed real-time analyses of energy flows and capacity bottlenecks of the highly integrated energy systems with high accuracy and in reasonable time scale, ii) assist network operators to optimise the performance of the existing energy systems to minimise the cost of integrating low carbon generation and demand, and iii) assist policy makers to design effective policies and regulations for economic and sustainable energy network development.

Planned Impact

The industrial beneficiaries are domestic consumers, network operators, renewable generation, and energy suppliers.
1. The ultimate beneficiaries will be end domestic customers. The multi-vector energy systems provide two routes to transmit energy, which provide more flexibility for end customers to interact with multi-vector systems over time. They can have low energy costs by storing and generating energy as appropriate, or switching demand from one type of source to the other in response to energy prices and energy system conditions.
2. Network operators will benefit from the research. The research develops fundamentally new approaches in modelling multi-vector energy carriers, which underpins the optimisation of demand response to increase the utilisation of existing energy transport infrastructure. The optimal management will provide cheaper alternatives by exploring the potential capacity from the existing infrastructure to release network constraints to support demand and generation growth. By doing so, the needed network investment can be deferred or ideally avoided, without compromising network security and quality of supply.
3. Renewable generation can also benefit. Due to the intermittency, renewable energy can not be dispatched to serve base loads and are normally constrained off when the electricity networks are congested. This incurs not only monetary loss for renewable generation companies but also a waste of clean energy for the society. The proposed research provides an alternative route- gas networks for renewable energy to be delivered to end-use customers. The benefits for renewable generation are the reduction in output constraint at the time of electricity systems being stressed.
4. The last group beneficiary is energy suppliers. Energy suppliers have to pay network operators for their use of the energy systems to transport energy. The proposed research can maximise the existing energy infrastructure to minimise future reinforcement or upgrades needed to support increasing generation and demand. This decreasing investment means energy suppliers will pay less for using the infrastructure.

The benefits to the UK society lies in assisting national energy security and cleanness, helping policy making, and promoting business opportunities.
1. The multi-vector energy networks will improve security of supply. When one system is undergoing sever interruption or congestion, the other system will still function properly as a backup to transport the energy. The linkage between the two energy systems reduces end customers' energy interruption and deterioration in security and quality of supply during severe times. The multi-vector systems can also enable more penetration of renewable energies, which are wasted due to network congestion. It will reduce the nation's dependence on scarce fossil-fired resources and increase national energy security and cleanness.
2. The proposed work will be valuable for future low carbon energy system modelling, planning, and operation. It is not only because it will enable more renewable penetration on a large but also because more efficient utilisation of existing energy transport infrastructure. It will benefit renewable penetration, investment saving and CO2 reduction. The findings will inform the energy network regulator, policy makers, and the government on the paradigm shift needed in the design, operation, and management of energy systems for a low carbon future.
3. The work will also inform new knowledge and research areas. The proposed research will benefit several academic communities through the large-scale, multi-level, non-linear modelling and optimisation of closely coupled gas and electricity networks. The scientific knowledge from this research creates new business opportunities for third parties who are interested in providing services for multi-vector energy system planning, operation and economics, and implementation of cross-vector demand response.

Publications

10 25 50
 
Description Once blending H2 into natural gas systems, it is essential to consider the security and quality of natural gas. I have developed a mathematical tool to measure the change of gas quality due to the blending. In addition, a novel optimal management tool is designed to manage the blending by mixing H2 with other gases.

It is also found that in multi-vector energy systems, there are severe uncertainties from renewable, flexible demand, and energy prices. Traditional deterministic or stochastic approaches cannot model the uncertainties effectively and they could cause huge economic losses. By contrast, the two-stage optimisation approach is more effective in capturing uncertainties and thus minimise the costs incurred due to the uncertainties.

For a flexible future energy system with nearly zero emissions, energy storage plays an essential role. Apart from electricity energy storage, natural gas, heating/cooling via borehole storage are also important. By coordinating these systems, it is possible to capture on their advantages to produce various services needed by the energy systems.
Exploitation Route It essential to consider gas quality when blending H2 into gases. The management tools can help to manage the blending, which can maintain not only gas quality but also pipeline security.

Two-stage robust optimisation as a new mathematical model, it can be a better tool for managing energy systems with severe uncertainties.

Technology and policy should be developed to encourage the coordination planning and operation of these storage systems.
Sectors Energy,Government, Democracy and Justice

 
Description I have been discussing with local councils in Shanghai (China) to adopt my research in multi-vector demand response scheme there to mobilize demand response for their energy balancing. I have secured a project from a Chinese institute to develop novel energy management systems for integrated microgrid systems. The techniques and approaches were developed from this project. I have been sponsored by the British Council to work with ESTIA France to develop a roadmap towards low-carbon communities for UK and France. This work can inform policy making and developments of new technologies.
Sector Energy
Impact Types Economic

 
Description Discuss the potential applicaiton of my resarch to Shanghai power networks in China
Geographic Reach Asia 
Policy Influence Type Contribution to a national consultation/review
Impact To quantity the importance of demand response in Shanghai to support local electricity network balancing.
 
Description Alliance Hubert Curien programme
Amount € 5,000 (EUR)
Organisation British Council 
Sector Charity/Non Profit
Country United Kingdom
Start 10/2019 
End 09/2021
 
Description Coordinated Development of New Energy Technologies and Multi-Energy Internet
Amount £24,000 (GBP)
Funding ID 2016-RLWK7-10435 
Organisation British Council 
Sector Charity/Non Profit
Country United Kingdom
Start 08/2017 
 
Description Energy management system for integrated micro grids
Amount £111,000 (GBP)
Organisation Government of Shanghai 
Sector Public
Country China
Start 04/2017 
End 03/2018
 
Description Global Research Scholarship Scheme - Energy, energy systems and the environment (Mr Yongzhi Zhou)
Amount £6,000 (GBP)
Organisation University of Bath 
Sector Academic/University
Country United Kingdom
Start 09/2015 
End 04/2016
 
Title Alternative gases 
Description A new model for quantifying the impact of alternative gases on gas systems. 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact A generic dynamic multi-vector energy system model by linking electricity and gas networks for quantifying the impact of alternative gases and hydrogen on gas pipelines 
 
Title Blending H2 into natural gas systems 
Description I have developed a novel approach to analyse the impact of blending H2 into natural gas systems. Many natural gas quality indexes, Wobbe index, Combustion Potential can be quantified. 
Type Of Material Data analysis technique 
Provided To Others? No  
Impact A journal paper is under preparation. 
 
Title Chance-constrained energy hub 
Description This research develops a chance-constrained optimisation model for energy hubs. This method can respect the tolerance of overloading for branches for a short period. 
Type Of Material Computer model/algorithm 
Year Produced 2018 
Provided To Others? Yes  
Impact No yet. 
URL https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8436429
 
Title Leontief Matrix 
Description I have developed a techno-economic model for multi-vector system analysis. 
Type Of Material Data analysis technique 
Provided To Others? No  
Impact A technical-economic model by Leontief Matrix and system risk technique for quantifying the importance of energy supply to other economic sectors 
 
Title Pearson Product-Moment 
Description My student has developed a statistic model by using Pearson Product-Moment for modelling the correlation between customer energy usage profiles and external weather conditions 
Type Of Material Data analysis technique 
Provided To Others? No  
Impact It can be used for modelling the correlation between customer energy usage profiles and external weather conditions. 
 
Title Polynomials approximation 
Description I have developed an ultra-fast multi-vector energy system analysis tool which is realised by polynomials approximation 
Type Of Material Computer model/algorithm 
Provided To Others? No  
Impact It can approximate the states of multi-vector energy systems without whole-system simulation, saving a lot of computational time. 
 
Title Two-Stage Distributionally Robust Optimization for Energy Hub Systems 
Description This is a two-stage optimisation model for multi-vector energy system operation. 
Type Of Material Computer model/algorithm 
Year Produced 2019 
Provided To Others? Yes  
Impact This article proposes an innovative distributionally robust optimization model to operate EHS with an energy storage system (ESS), considering the multimodal forecast errors of photovoltaic (PV) power. Both battery and heat storage are utilized to smooth PV output fluctuation and improve the energy efficiency of EHS. This article proposes a novel multimodal ambiguity set to capture the stochastic characteristics of PV multimodality. A two-stage scheme is adopted, where 1) the first stage optimizes EHS operation cost, and 2) the second stage implements real-time dispatch after the realization of PV output uncertainty. The aim is to overcome the conservatism of multimodal distribution uncertainties modeled by typical ambiguity sets and reduce the operation cost of EHS. The presented model is reformulated as a tractable semidefinite programming problem and solved by a constraint generation algorithm. Its performance is extensively compared with widely used normal and unimodal ambiguity sets. The results from this article justify the effectiveness and performance of the proposed method compared to conventional models, which can help EHS operators to economically consume energy and use ESS wisely through the optimal coordination of multienergy carriers. 
URL https://purehost.bath.ac.uk/ws/files/197423706/Two_Stage_Distributionally_Robust_Optimization_for_En...
 
Title borehole system 
Description This research develops a multi-local energy system, which contains many energy vectors, particularly borehole, heating storage. 
Type Of Material Computer model/algorithm 
Year Produced 2018 
Provided To Others? No  
Impact Not yet. 
URL https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8550636
 
Description Beihang University 
Organisation Beihang University
Department Department of Aerospace Propulsion Theory and Engineering
Country China 
Sector Academic/University 
PI Contribution I visited Beihang University to give lectures on my research and also supervise students there, working multi-vector energy systems
Collaborator Contribution Beihang University has sent one visiting student to Bath, who spent three months at Bath working with me.
Impact 1. C. Gu and Y. Song, "Distribution Network Pricing for Uncertain Load Growth using Fuzzy Set Theory", IEEE Transactions on Smart Grid, 2016
Start Year 2014
 
Description Hohai University 
Organisation Hohai University
Country China 
Sector Academic/University 
PI Contribution We work together to use the metering system to monitor the security of wind turbines.
Collaborator Contribution This PI brings knowledge in wind power systems into the collaboration.
Impact Z Fu, Y Luo, C Gu, F Li, Y Yuan, Reliability analysis of condition monitoring network of wind turbine blade based on wireless sensor networks, IEEE Transactions on Sustainable Energy
Start Year 2017
 
Description Iowa State University 
Organisation Iowa State University
Department Department of Plant Pathology and Microbiology
Country United States 
Sector Academic/University 
PI Contribution This is a new collaborator in the US. The Fellowship helps the PI to expand his connection to the US. The collaboration mainly looks at improving local energy network efficiency through novel techniques in load modelling.
Collaborator Contribution Iowa State University will contribute to the project by developing mathematical load characterising tools.
Impact Journal paper under preparation. The PI is invited to visit Iowa University.
Start Year 2017
 
Description National Grid UK 
Organisation National Grid UK
Country United Kingdom 
Sector Private 
PI Contribution Joint proposal and publications.
Collaborator Contribution The two sides have drafted a NIA proposal submitted to NG strategy competition.
Impact C Gu, X Zhang, K Ma, J Yan, Y Song, Impact Analysis of Electricity Supply Unreliability to Interdependent Economic Sectors by an Economic-Technical Approach, 2018, Renewable Energy
Start Year 2017
 
Description Shanghai Jiao Tong University 
Organisation Shanghai Jiao Tong University
Country China 
Sector Academic/University 
PI Contribution I have been visiting Shanghai Jiao Tong University for a couple of times to discuss collaboration. I also have spent a bit time to work with researchers there design new control strategies for CHPs
Collaborator Contribution Shanghai Jiao Tong University has sent one visiting student and one scholar to work with me on the project. The scholar spent one year in Bath.
Impact 1. X. Lv, X. Liu, C. Gu, Y.Weng, "Determination of safe operation zone for an intermediate-temperature solid oxide fuel cell and gas turbine hybrid system", Energy, 2016 2. D. Xie, H. Chu, C. Gu, "A Novel Dispatching Control Strategy For EV's Intelligent Integrated Stations", IEEE Transactions on Smart Grid, 2015 3. C. Gu, D. Xie, J. Sun, X. Wang and Q. Ai, "Optimal Operation of Combined Heat and Power (CHP) System Based on Forecasted Energy Prices in Real-time Markets", Energies, 2015, 8(12), 14330-14345
Start Year 2014
 
Description Sichuan University 
Organisation Sichuan University
Country China 
Sector Academic/University 
PI Contribution New methods to model mulit energy systems particularly at loca level.
Collaborator Contribution New methods to model electric vehicles and also the control strategies for electric vechies.
Impact S Hu, Y Xiang, J Liu, C Gu, X Zhang, Y Tian, Z Liu, J Xiong, Agent-based coordinated operation strategy for active distribution network with distributed energy resources, IEEE Transactions on Industry Applications 55 (4), 3310-3320 C Gu, C Tang, Y Xiang, D Xie, Power-to-gas management using robust optimisation in integrated energy systems, Applied energy 236, 681-689 D Huo, C Gu, K Ma, W Wei, Y Xiang, S Le Blond, Chance-constrained optimization for multienergy hub systems in a smart city, IEEE Transactions on Industrial Electronics 66 (2), 1402-1412 X Yan, C Gu, F Li, Y Xiang, Network pricing for customer-operated energy storage in distribution networks, Applied energy 212, 283-292 W Yang, Y Xiang, J Liu, C Gu, Agent-Based Modeling for Scale Evolution of Plug-In Electric Vehicles and Charging Demand, IEEE Transactions on Power Systems, 2018
Start Year 2018
 
Description Tianjin University 
Organisation Tianjin University
Country China 
Sector Academic/University 
PI Contribution The PI is working together with Tianjin University China to study the state estimation for multi-energy system.
Collaborator Contribution This PI brings knowledge in multi-energy system modelling into the collaboration.
Impact Shaoyun Ge, Xiaoou Liu, Hong Liu, Chenghong Gu, and Lukun Ge, Research on unit commitment optimization of high permeability wind power generation and P2G Journal of Renewable and Sustainable Energy 10, 034702 (2018); https://doi.org/10.1063/1.5012777
Start Year 2017
 
Description Zhejiang University in China 
Organisation Zhejiang University
Country China 
Sector Academic/University 
PI Contribution I have visited Zhejiang University to give lectures on multi-energy system modelling and economics in July 2015 and January 2016. Working as a visiting scholar, I stayed at Zhejiang for one month to have in-depth discussion on the proposed research with Zhejiang researchers.
Collaborator Contribution Zhejiang University has sent one PhD student, working with me on the project. I have been appointed as a Visiting Researcher by Zhejiang University since 10/2014 for a period of 3 years.
Impact C. Gu and Y. Song, "Distribution Network Pricing for Uncertain Load Growth using Fuzzy Set Theory", IEEE Transactions on Smart Grid, 2016
Start Year 2014
 
Description An invited talk at UK-China researcher link workshop in 2017 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact This is an UK-China workshop to bring together researchers UK and China to discuss the lateste progress and futhre direction of Enegy Internet research.
Year(s) Of Engagement Activity 2017
URL http://me.sjtu.edu.cn/news/11120.html
 
Description Bath seminar 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Third sector organisations
Results and Impact I have introduced my research work on the second Bath/Tsinghua smart grid workshop held in October 2015, hosted by Bath.
Year(s) Of Engagement Activity 2015
 
Description International Conference on Global Energy Interconnection 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact I am going to present the research finding at 2016 International Conference on Global Energy Interconnection, March 2016 Beijing China.
Year(s) Of Engagement Activity 2016
 
Description University visit 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact I was invited to gave a 'invited talk' on multi-energy system modelling by Durham University for postgraduate students.
The students were very active and interested in looking at the energy landscape from a new aspect.
Year(s) Of Engagement Activity 2016
 
Description Visit to Belfast 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact I was invited to give a presentation to introduce my fellowship research on 'UK-China' consortium on shaping low carbon energy further.
There were around 50 participants from both UK and China, including researchers, industrialists and government representatives. They were very interested in my work and there were many questions and discussions afterwards.
Year(s) Of Engagement Activity 2016
 
Description Visit to China 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact I was invited by Zhejiang University, Beihang University, Shanghai Jiao Tong University to give lectures on multi-energy system modelling and economics in July 2015 and January 2016.
Year(s) Of Engagement Activity 2014,2015,2016