About the Author

Dr Susan Claire Scholes is a postdoctoral research associate with the Supergen Energy Networks Hub at Newcastle University

The new extraordinary?

On 10^th May 2020, the GB electricity network encountered an extraordinary occurrence which, with the increase of electricity generation by renewable sources, is unlikely to remain extraordinary in future times. 

During the early hours of the morning on Sunday 10^th May, there was forecasted high wind along with other inflexible generation that would lead to an excess of electricity generation at a time of low demand.  This could lead to system instability and the associated problems of system imbalance.  Shortly before this event, National Grid Electricity System Operator (ESO) had introduced a new control mechanism that was targeted at the changes in power needs and potential excess generation as a result of the COVID-19 pandemic (less capacity required by industry along with greater numbers of people working from home).  This was the voluntary termination of distributed generation known as Optional Downward Flexibility Management (ODFM).

Optional Downward Flexiblity Management (ODFM)

ODFM is a new tool to balance the system at times of low demand.  When extremely low demand coincides with periods of higher generation due to renewable sources this could lead to significant operational risk.  ODFM allows providers to offer termination of their services for a period of time to reduce electricity generation and help balance the system.  Along with this, the National Grid has also recently approved a Grid Code modification allowing the ESO to instruct a Distribution Network Operator (DNO) to disconnect embedded generation in emergency events.  On May 10^th 2020, the forecast suggested the need to use the Grid Code service during a period of high forecasted wind generation and low demand in the early hours of the morning.  During the actual event, however, the timing of this wind peak shifted to between the hours of 04:00 – 07:00 and emergency termination of embedded distributed generation was not necessary¹.  Embedded generation was cut through the new ODFM service.  The peak generation was further managed using Market Coupling, with lower importing from and some exporting to our European links via the interconnectors. 

The interconnector use can be seen in the figures below.  Figure 1 shows the interconnector use during this period of low demand and high generation in GB (04:00 – 07:00 outlined), where import to GB is positive and export from GB is negative.  The second figure (Figure 2) is the interconnector use a week earlier during normal demand and generation.  These clearly show that the Market Coupling service was taken advantage of on 10^th May.

Services from interconnectors

Selling power to the continent to create exports on the interconnectors, to help balance our system, is an action that National Grid ESO prioritises above the new ODFM, providing the associated costs (price differentials) are financially beneficial to GB; and is an example of the many services interconnectors could provide to the electricity system.

Further services that could be on offer from the interconnectors include Short Term Operating Reserve (STOR), black start or frequency response.  Of course, the availability of these services will depend on the price differential to allow it to be financially beneficial to use the interconnectors in this way.  Currently GB has 5 GW of interconnector capacity (2 GW to France (IFA), 1 GW to the Netherlands (BritNed), 500 MW to Northern Ireland (Moyle) (although only half of this is available due to subsea cabling defects), 500 MW to the Republic of Ireland (East West) and the most recent addition 1 GW to Belgium (NEMO)).  Further interconnectors are planned; at the time of writing an additional 6.7 GW of power is scheduled to become available through new interconnector links by 2022.  This will more than double the power that is available to Great Britain through the interconnectors.  This increase in power availability through the numerous additional interconnectors is likely to have an effect on the price differences between countries.  The predicted decreased price differential will reduce the earnings from the sale of power through the interconnectors so the purchase from/to Europe will be less financially beneficial, potentially leading to other opportunities for the use of interconnectors for ancillary services.

Multi-Vector Solutions

There are other potential solutions for an imbalance of demand and generation in the future.  These are multi-vector solutions that involve the whole energy system.  Excess electricity generation could be used to create hydrogen to then either be stored for future use; or this hydrogen could be blended into the gas network.  In addition to this, the consumer could play a more active role in system demand by participating in active demand response (ADR).  In ADR the consumer may adjust their demand in response to the requirements of the ESO; importantly, the consumer would need to have the flexibility to increase demand or reduce demand (e.g. charging of electric vehicles at appropriate times, smart appliances such as washing machines and dishwashers).

Limitations of interconnectors?

There may, however, be limitations on the use of interconnectors for these balancing services.  The time difference between GB and the interconnected countries is one hour, and therefore times of low demand in GB are likely to also be times of low demand in these countries.  Furthermore, power exchanges over the interconnectors are driven by price differences, whether it is cheaper to import power or more beneficial to export power.  During times of low demand and high generation, we would need to ensure we are exporting power, which would mean ensuring our prices encourage this, but we would still be reliant on the need of other countries to import this power.  In addition to this, the capacity on the interconnectors may be capped due to operability constraints, thus limiting the power availability for these services.

Lessons Learnt

Extreme events of today may be an insight into our future challenges, for the net-zero greenhouse gas emissions target of 2050.  The changes in energy needs highlighted by the COVID-19 pandemic have allowed us to anticipate future energy dilemmas that may occur due to the likely excess electricity generation from renewables.  This has given us an advanced insight into the potential solutions for these problems.

On 10^th May 2020, intelligent use of the interconnectors allowed us to prioritise electricity generation from renewable sources within GB.  This demonstrates the benefits of interconnectors to:

• balance our system
• meet demand at a good price (importing from other countries) and
• export excess generation (to other countries at a low price) during times of low demand and high generation from renewable sources.

Thus, both ends of the interconnected countries benefit from this intelligent use of interconnector services.

References:

https://www.current-news.co.uk/news/national-grid-eso-reduces-embedded-generation-over-bank-holiday-weekend

Acknowledgements:

I would like to acknowledge the assistance of Dr Sara Walker and Dr David Greenwood, both from Newcastle University, in the preparation of this article.

From the 29 April to the 1 June 2020, the Supergen Energy Networks Hub organised and delivered a six week online conference programme which attracted more than 480 registrations.

Phil Taylor, opened the conference with an overview of the Energy Networks (EN) Hub introducing the Supergen EN Co-Investigators and the Research Project Coordinators, working across the hub from Newcastle, Leeds, Manchester, Cardiff and Bath and illustrating how the hub community has grown since starting in October 2018.

Phil discussed the core research programme as well as the activities and roles which are currently being undertaken by the hub as well as the 3 Working Groups on Architectures, Climate Adaptation & Mitigation and Markets & Regulation which have been established.

Conference Sessions:

Chaired by Nazmiye Ozkan, Cranfield University, we held three separate Network Interdependency sessions.  The first session was presented by Bethan Winter, Wales & West Utilities on Network Interdependencies: Gas Networks: The Key to Unlocking Renewable Energy. Bethan discussed how networks are becoming increasingly integrated and that investment in new technologies will be required with whole system and regional modelling essential to provide insight on future network usage.

The second session concentrated on the UK Power Blackout, August 2019 and this was presented by Janusz Bialek, Newcastle University.  Janusz talked about the UK power outage on the 9 August 2019 and what this tells us about GB power systems.  He advised that the power system reacted largely as expected to a non-secured contingency, however unexpected train failures caused wide spread disruption and public anger, concluding that interactions between the power system and critical infrastructures should be reviewed.

Spyros Skarvelis-Kazakos, Sussex University and Mathaios Panteli, Manchester University, presented our third Network Interdependencies session.  They presented the outline of their future work based on COVID19 and the impact of interdependent infrastructure including resilience and sector interdependencies.

Our session on Climate Adaptation & Mitigation was presented by Alberto Troccoli, World Energy & Meteorology Council (WEMC). Alberto discussed Energy & Meteorology (weather and climate), looking at the basics of climate modelling and climate impacts on networks which could potentially cause large losses. The session was chaired by Konstantinos Chalvatzis, University of East Anglia.

Mary Susan Abbo, Centre for Research in Energy and Energy Conservation (CREEC) presented a keynote presentation on Energy Networks in Uganda and Africa.  The presentation including statistics on the energy status in Uganda, noting that 69% of Ugandans use three stone fires for cooking.  Mary Susan discussed several large Hydropower Projects which are currently in planning across the country.

CREEC goal is to enhance access to modern types of energy through research, training and consultancy in East Africa

Mary Susan Abbo

A further session on International Perspectives was chaired by Jianzhong Wu, Cardiff University. Abhishek Shivakuma and Vignesh Sridharan, from KTH Royal Institute of Technology Stockholm, Sweden presented a session on Co-Creating Energy-Land-Water resource, planning models with national governments to achieve Sustainable Development Goals (SDG’s). The session looked at the challenges in working towards SDG’s as well as interlinkages between systems looking at OSeMOSYS (Open Source Energy Modelling System)

On the 11 May we welcomed our first panel session of the online conference.  Chaired by Karen Henwood, Cardiff University, the panel consisted of both Industry and Academia who presented on the Societal Perspectives of Energy Networks. The session was entitled: Network Resilience and Intersectoral Connectivity: Energy Infrastructure, Carbon Literacy and Vulnerability. The session started with a short talk from Peter Smith, National Energy Action (NEA).  Peter discussed existing drivers for fuel poverty and NEA’s collaborations with networks, as well as their previous and current work with GDNs and DNO’s and opportunities for upcoming RIIO2 consultation.

Muditha Abeysekera, Cardiff University presented his work on Decarbonisation of the Public Sector which included a background of the public estate which consumes 6% of the UK’s energy supply, with the government spending over £2billion per annum on its energy bills. Muditha concluded his talk advising that ‘good quality energy data collection and analysis is an important area that needs improvement and that accessible, user -friendly ‘decision support tools’ are needed to identify improvement opportunities of public sector energy systems’.

Our third talk in this session was from Simon Roberts, Centre for Sustainable Energy (CSE). Simon discussed why we need an energy system that is both ‘smart and fair’ and the role of energy network companies in delivering it.

Keith Owen, Northern Gas Networks (NGN) discussed the Net Zero Challenge, GB Energy Consumption and advised on the numerous GB Gas Industry projects throughout the country, specifically those which NGN are involved in: HyDeploy and H21 (Link) as well as an update on the InTEGReL (Integrated Transport Electricity and Gas Research Laboratory) project based in Gateshead which is in collaboration with Newcastle University, Northern Powergrid and Siemens among others.

Carlos Ugalde-Loo, Cardiff University presented his work on flexibility provision in District Cooling Systems looking at Integrated Energy Systems (IES) and how ‘IES can use complementary advantages of having various energy vectors.’ We also had presentations from Spyros Skarvelis-Kazakos, Sussex University and John Barton, Loughborough University which included information on the role of hydrogen storage in resource aggregation and virtual power plants as well as Hydrogen and Heat Delivery. The session was chaired by Upul Wijayantha, Loughborough University.

The Early Career Researcher (ECR) session on the 20 May, chaired by Robin Preece, Manchester University consisted of several presenters from Academia and Industry.  The session focused on Career Pathways for Early Career Researchers starting with a talk from Keith Bell, Strathclyde University and his pathway to becoming a Professor as well as a talk from Tingyan Guo, consultant at Deloitte and how she has moved into Industry following completion of her PhD in Electrical Energy and Power Systems.  We also had talks from Rose Chard, Energy Systems Catapult, Celia Butler, Synopsys, Jacqueline Edge, Imperial College and Nick Wooley, ev.energy.

As part of the conference we held an offshore session which was hosted by Lars Johanning, University of Exeter and featured talks from Industry and Academia. Simon Cheeseman, Offshore Renewable Energy Catapult discussed Tidal Stream & Hydrogen System Integration, how the energy system will differ significantly to the existing energy system in 2050, with the majority of electricity expected to be generated by renewable sources including offshore wind.

Ajit Pillai, University of Exeter talked about the complex bathymetry which is considered when locating wind turbines such as high seabed slope and wrecks and AI approaches for the Offshore Cable Network reliability based design. The third talk in this session was from David Parish, Planet A solutions, discussed a case for symbiotic, cross vector, multi technology networks and the need for a flexible microgrid with cross vector energy flows preventing network stress.

Michael Pollitt, Cambridge University spoke about the Regulation of Energy Markets including his work on the MERLIN (Modelling the Economic Reactions Linking Individual Networks) project.

‘Having a supportive regulatory environment around flexibility procurement is crucial’

The session also included a talk from Rebecca Willis, Lancaster University. Rebecca discussed getting Energy Governance right, the GB Energy Governance: current institutions and responsibilities which include BEIS, DfT and Defra and how an Energy Transformation Commission, a coordinating body, may be able to act on behalf of the government by pulling together the different government departments

The Digital Networks Session, chaired by Myriam Neaimeh, Alan Turing Institute involved 3 presentations from Myriam, Dragan Cetenovic, Manchester University and Xavier Bellekens, Strathclyde University. 

[Cyber Security] costing £27billion p.a)

The session included information on Digital Twinning, a cloud based platform to modernise energy data access and network planning as well as real-time state estimation and FDI (False Data Injection) attacks and the challenges of cyber-threat detection and mitigation for energy networks. Understanding complex threats from Tier 1 to Tier 6 attackers and the energy challenges which need to be thought about in anticipation of a Cyber attack.

Our final conference session was an Industrial keynote from Emma Pinchbeck, Energy UK and Rebecca Williamson, Renewable UK.

Emma and Rebecca discussed how to get to net zero and the changing energy industry in relation to electricity, hydrogen and land use, etc as well as technology innovation to make use of onshore and offshore wind.

Chair, Sara Walker, Newcastle University, concluded the conference with a summary of the online programme.

Conclusion

Over the six week period we delivered fourteen online conference sessions with thirty-two speakers from Industry and Academia and a live attendance of between 50 – 100 delegates dialling in to each session. 

A feedback form has been sent through to all conference delegates, our aim is for their feedback to add to our own reflections.

[The conference] was a great event –lots of interesting discussions and ideas for potential proposals

In moving forward we aim to ensure sessions have a more diverse range of speaker and that dial in details can be distributed in a more efficient way.

‘The conference has gone from a potential another cancelled event to a great success!’

If you would like any further information regarding the online conference programme please contact Lindsey Allen or Linda Ward supergenen@newcastle.ac.uk

Feedback provided to BEIS Panel of Technical Experts on ‘Modelling de-rating factor ranges for interconnected countries in the capacity market in the 2020 Electricity Capacity Report’

The GB capacity market is designed to ensure that there is enough electrical generating capacity to meet peak demands. Approximately £700 million was allocated in the ‘T-4’ capacity auction in 2020, with the portfolio covering a range of technologies, including renewables, demand side response, and interconnectors. With the total capacity of electrical interconnectors doubling to more than 20% of peak demand in the next five years, they can and do make a substantial contribution to GB system security.

Determining a monetary value for the security contribution of interconnectors is difficult compared to that of either conventional or renewable capacity, as interconnectors can both increase and reduce system demands. Earlier this month, the Supergen Energy Network (SEN) Hub responded to a call for feedback from the Electricity Market Reform (EMR) Delivery Body on the methodology for calculating interconnector de-rating factors (a link to our response). The call is of interest to the SEN hub as it lies at the intersection of network operation with ‘Markets and Regulation’ and ‘Risk and Reliability’ work packages.

What is the GB Capacity Market for?

The UK Government’s EMR reforms of 2013 attempts to solve the ‘missing money’ problem in medium term planning of power systems. The problem states that energy-only markets fail to incentivise the building of generation due to the marginal cost of energy (in £/MWh) being too low when the system margin is tight. The EMR introduced a number of reforms to incentivise the investment in capacity required to meet system peaks, one of which was the GB capacity market.

For conventional generators (such as nuclear or gas), the method of calculating the capacity market value of a generator is relatively straightforward. Historic data from forced outages (periods where plant is unable to supply power due to unexpected equipment failure) are collected; from this, an overall de-rating factor is calculated based on the likelihood of a generator being unavailable during a system peak. A similar method can be used for renewable generators, based on the coincidence of meteorological patterns and demand. Generators are then paid in proportion to their de-rating factor.

How are the Interconnectors accounted for in the analysis?

Interconnectors are treated in a similar way in the calculation of their contribution to security, using de-rating factors. However, interconnectors are generally more complex than generators, with power flows largely driven by price differentials. For example, nuclear power on the French system tends to be inexpensive compared to gas turbines that are common in the GB system, and so the GB system frequently imports through the French interconnector. On the other hand, if the energy price is higher on the French system (perhaps due to unforeseen nuclear generation outages) then the interconnector is likely to export to France, potentially reducing security.

The EMR Delivery Body models the countries to which the GB system is connected using an ‘economic dispatch model’. Prices during system stress events are estimated and the resulting flows used to determine interconnector de-rating factors. The model uses many decades of weather data, allowing the impact of increasing penetrations of renewables in future years to be factored in.

The estimation of de-rating factors for interconnectors across many countries years into the future makes for a very challenging modelling task. Whilst the approach used by the EMR Delivery Body has only been presented at a high level (i.e., with few technical details), there were two issues which we identified and highlighted in our response. These points were based on a combination of our understanding of these high-level details (as described here) and the published capacity market rules.

What was our feedback?

We considered their approach using the principle of parsimony: a model should be as concise as possible, whilst still being able to explain all significant phenomenon. Implicitly, this requires a judgement of what constitutes the main ‘thing’ that a model is trying to predict or explain.

It follows, therefore, that the method should be validated against the model out-turn (the ‘reality’ the model is predicting). In this case, the out-turn is the expected flows of interconnectors during formal system stress events up to five years in the future. Only a validation against an approximation of this reality is likely to be meaningful, not least because there is yet to be a formal system stress event, but also because there are many exogenous factors (e.g. transmission constraints) which can have a significant impact on resultant power flows.

This point is particularly relevant as, until last year, the capacity market rules stated that the economic dispatch model should be compared against an historic benchmark. There are several reasons as to why this hindcast-based approach is not advisable – for example, the generating fleet in countries such as Germany is due to change significantly in the next five years. However, it is our view that the outputs of a model should still be validated publicly, with decision makers made aware of the method of validation and the results. The validation could be, for example, against periods of high Loss of Load Probability (LOLP), or some other indicator of system stress.

The second point we raise is on a similar topic. If you do compare historic interconnectors flows against the LOLP, it appears to be the case that some countries tend to export when the LOLP is high, whilst others tend to import. (Exports during stress periods could occur, for example, if two countries have highly correlated peak demands.) As a result, some interconnectors may in fact be tending to diminish the system security, even if most interconnectors are improving security. The capacity market rules do not explain how this effect could be taken into account in the analysis. Our judgement is that this is a major part of the ‘reality’ of interconnectors, which should therefore be recognised by the method.

What is the future for interconnectors within the GB system?

Generally, it is known that interconnectors provide huge benefits to the GB system. Social welfare benefits of interconnectors are measured in hundreds of millions of pounds per year, with strong evidence of positive impacts in terms of reduced system carbon intensity and increased network resilience. It is important, however, for methods of remuneration within the capacity market be made robust, so that decision makers and investors can be fully informed as to their value within the system, both today and in the future.

Read our response submitted to BEIS’ Panel of Technical Experts (PTE)

Author Bio

Dr Matthew Deakin is a postdoctoral research associate with the Supergen Energy Networks Hub at Newcastle University. His research interests include whole energy systems analysis, power system planning and operations, and smart grids.

Additional contributions to this post were made by Sarah Sheehy (Durham University), Dr David Greenwood (Newcastle University), Prof. Furong Li (University of Bath), Dr Robin Preece (University of Manchester), Dr Sara Walker and Prof. Phil Taylor (Newcastle University).

About the Author

Richard Smithson is a retired GP, married to Sue, father and grandfather, climate activist and concerned citizen, lives in Whitley Bay.

‘In the absence of decisive action from our politicians, it is important that local communities act together to reduce our carbon footprint. Increased use of hydrogen both in domestic supplies and transport would be a big step in the right direction. We are also considering community ownership of solar farms and promoting cycling and cheaper public transport  to get people out of their cars. Electric vehicles can help in the short term but there is no single solution and we must try a multifaceted approach’

Richard Smithson

The Event

While the UK is the first country to pass into law net-zero emissions by 2050, much work needs to be done across government, public, private and voluntary sectors, and communities to tackle this immense challenge. Some local governments, cities, institutions and universities have declared a climate emergency, but what are the next steps to actually ending greenhouse gas emissions in all sectors in the UK and throughout the world?

On the 5 March, the Supergen Energy Networks Hub (SupergenEN) in collaboration with the National Centre for Energy Systems Integration (CESI) and in association with Extinction Rebellion, held a Public Engagement event at the Dove Marine Laboratory, Cullercoats, Newcastle upon Tyne.

Over 65 people attended the meeting which focussed on the UK governments aim for net-zero emissions by 2050, discussing a multi vector energy approach and in particular, Hydrogen for Heat & Transport as well as Climate Change Adaptation – Resilience.

The talk by Phil Taylor, Newcastle University, introduced the Integrated Transport Electricity Gas Research Laboratory (InTEGRel) project, the UK’s first multi-sector energy networks research centre, a collaboration between Newcastle University, Northern Powergrid and Northern Gas Networks. As well as the e4future project, a collaboration between Newcastle University & Imperial College London and a number of Industrial and government partners including Nissan, e-on, National Grid and the Department for Business, Energy & Industrial Strategy (BEIS).

The talk was followed by a Q&A and a “post-it note” session. This enabled attendees to ask questions and write down their concerns and suggest ideas to reduce Carbon Emissions in the North Tyneside and wider region .

Questions included: Are schemes available for installing Domestic Solar Panels? What are the benefits of Tidal Energy and is this something that could be considered? Is it expensive to retrofit air source heat pumps to homes? When will Hydrogen Boilers be available to buy? Is Biomass worth exploring?

Outcomes

After the session we gathered a number of project ideas which we hope to look into in more detail with the help of the North Tynside Community and in collaboration with SupergenEN and CESI.

For more information please contact: supergenEN@newcastle.ac.uk or visit our website.