{"id":243,"date":"2020-06-30T14:13:06","date_gmt":"2020-06-30T13:13:06","guid":{"rendered":"https:\/\/blogs.ncl.ac.uk\/supergenenhub\/?p=243"},"modified":"2020-06-30T16:28:00","modified_gmt":"2020-06-30T15:28:00","slug":"potential-use-of-interconnectors-for-exteme-events-leading-to-net-zero-and-after","status":"publish","type":"post","link":"https:\/\/blogs.ncl.ac.uk\/supergenenhub\/2020\/06\/30\/potential-use-of-interconnectors-for-exteme-events-leading-to-net-zero-and-after\/","title":{"rendered":"Potential use of interconnectors for exteme events; leading to net-zero and after"},"content":{"rendered":"\n

About the Author<\/h2>\n\n\n\n
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Dr Susan Claire Scholes<\/a> is a postdoctoral research associate with the Supergen Energy Networks Hub at Newcastle University <\/p>\n\n\n\n

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The new extraordinary?<\/h2>\n\n\n\n

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nOn\n10th<\/sup> May 2020, the GB electricity network encountered an\nextraordinary occurrence which, with the increase of electricity generation by\nrenewable sources, is unlikely to remain extraordinary in future times.  \n\n\n\n<\/p>\n\n\n\n

During the early hours of the morning on Sunday 10th<\/sup> 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<\/a> (ODFM). <\/p>\n\n\n\n

Optional Downward Flexiblity Management (ODFM)<\/h2>\n\n\n\n

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<\/a> modification allowing the ESO to instruct a Distribution Network Operator (DNO) to disconnect embedded generation in emergency events.  On May 10th<\/sup> 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 \u2013 07:00 and emergency termination of embedded distributed generation was not necessary1<\/sup>.  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.  <\/p>\n\n\n\n

The interconnector use can be seen in the figures\nbelow.  Figure 1 shows the interconnector\nuse during this period of low demand and high generation in GB (04:00 \u2013 07:00 outlined),\nwhere import to GB is positive and export from GB is negative.  The second figure (Figure 2) is the\ninterconnector use a week earlier during normal demand and generation.  These clearly show that the Market Coupling\nservice was taken advantage of on 10th<\/sup> May.<\/p>\n\n\n\n

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Figure 1: Interconnector usage on Sunday, 10 May 2020 (Elexon)<\/em> <\/figcaption><\/figure>\n\n\n\n
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Figure 2: Interconnector usage on Sunday, 3 May 2020 (Elexon)<\/em> <\/figcaption><\/figure>\n\n\n\n

Services from interconnectors<\/h2>\n\n\n\n

Selling power to the continent to create exports on the\ninterconnectors, to help balance our system, is an action that National Grid\nESO prioritises above the new ODFM, providing the associated costs (price differentials)\nare financially beneficial to GB; and is an example of the many services\ninterconnectors could provide to the electricity system.<\/p>\n\n\n\n

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

Multi-Vector Solutions<\/h2>\n\n\n\n

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

Limitations of interconnectors?<\/h2>\n\n\n\n

There may, however, be limitations on the use of interconnectors\nfor these balancing services.  The time\ndifference between GB and the interconnected countries is one hour, and therefore\ntimes of low demand in GB are likely to also be times of low demand in these\ncountries.  Furthermore, power exchanges\nover the interconnectors are driven by price differences, whether it is cheaper\nto import power or more beneficial to export power.  During times of low demand and high\ngeneration, we would need to ensure we are exporting power, which would mean\nensuring our prices encourage this, but we would still be reliant on the need\nof other countries to import this power. \nIn addition to this, the capacity on the interconnectors may be capped\ndue to operability constraints, thus limiting the power availability for these\nservices. <\/p>\n\n\n\n

Lessons Learnt<\/h2>\n\n\n\n

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

On 10th<\/sup> May 2020, intelligent use of the\ninterconnectors allowed us to prioritise electricity generation from renewable\nsources within GB.  This demonstrates the\nbenefits of interconnectors to:<\/p>\n\n\n\n