Black Start from Non‑Traditional Generation Technologies

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Black Start from Non‑Traditional Generation Technologies Black Start from Non‑Traditional Generation Technologies Network Innovation Allowance June 2019 Technology capability and readiness for distributed restoration In partnership with: National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration Contents Executive summary 02 5 Technology capability – Resilience and restoration characteristics of 1 Introduction – Black Start emerging generation technologies 28 in Great Britain 04 5.1 Large and small wind power 28 1.1 Background 04 5.2 Solar PV power 31 1.2 The evolving energy landscape 05 5.3 Battery storage 33 1.3 Opportunities for non‑traditional 5.4 I&C DSR 35 technologies 06 5.5 Synchronous DERs 37 1.4 The future of Black Start 08 5.6 Electric vehicles and V2G 40 1.5 Project approach 09 5.7 Performance matrix 42 2 Non‑traditional technologies 11 6 Technology readiness 45 2.1. Non‑traditional technologies considered for Black Start 11 7 Technology readiness level 2.2. Growth of DER technologies 11 of non‑traditional technologies 48 7.1 Large wind 48 3 Existing Black Start 7.2 Small wind 49 technical requirements 19 7.3 Solar PV 49 3.1 Existing technical capability requirements 20 7.4 Battery storage 50 3.2 Procurement of technical capability 20 7.5 I&C DSR 50 3.3 The role of a Local Joint Restoration Plan 21 7.6 Synchronous DER 51 3.4 Applying technical requirements 7.7 Electric vehicles 51 to non‑traditional technologies 22 7.8 Summary of TRLs 52 4 Resilience and restoration performance characteristics 24 8 Barriers and roadmaps 53 4.1. Shutdown resilience characteristics 24 4.2 Black Start performance 25 9 Technology roadmaps 56 4.3 Restoration capabilities 27 10 References 61 Appendix A – TRL tables 62 b 01 National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration Executive summary • The ability to self‑start is a key attribute of conventional • Synchronous DER (e.g. biomass) can provide many TNEI Services Ltd (TNEI) was commissioned by National Grid ESO Black Start providers; and it is one that most of the same services as conventional Black Start to investigate the capability of non‑traditional technologies in the non‑traditional technologies and DER have limited providers, however this is typically on a much smaller or no capability. Sites can be limited by myriad of scale and so this must be considered when setting restoration of the GB power system in the event of a partial or total factors, including having no back‑up generation on site, technical requirements and “levels of service”. system shutdown. The project is a Network Innovation Allowance or insufficient resource at the time of the shutdown This is relevant for all DER sites, which are smaller (battery storage)/Black Start (solar). Several solutions are but more numerous than conventional providers. (NIA) project initiated by National Grid ESO, with support from readily available to address this issue, but all require a • A common issue throughout all DER sites is the resilience SP Energy Networks. The overall aim of the NIA project was to route to market for DER to justify the additional expense. of the communications infrastructure which, at present, • The majority of converter‑connected DER sites operate is typically not adequate to meet the requirements for provide insight into the capability of several prevalent non‑traditional with grid‑following inverters, rather than grid‑forming Black Start. A minimum level of resilience is stipulated technologies: wind, solar, storage, demand side response (DSR) inverters, which means they cannot generate their own in Connection Agreements and rarely are sites voltage signal for the purposes of network energisation incentivised to provide more than this minimum level. and electric vehicles (EV), to provide ancillary services to National and creating a Power Island. Instead, the grid‑following A route to market for DER would encourage more inverters require a voltage signal to latch onto which sites to incur additional cost to meet the necessary Grid ESO in the event that the GB network requires a Black Start. must first be created by a site with grid‑forming resilience requirements. capability. Upgrading this capability is straightforward • None of the technical barriers which exist are Responding to the significant changes in the energy An extensive research and stakeholder engagement if the necessary incentives are put in place. insurmountable, they only require appropriate landscape in the past decade, National Grid ESO are exercise yielded important insights into the capability commercial and regulatory support to ensure seeking to understand how renewable generation and of non‑traditional technologies, currently deployed these can be addressed to the benefit of all. distributed energy resources (DER) could facilitate the extensively across GB, to provide Black Start services. restoration of the GB power system with the decline It is recognised that a significant proportion of the and decommissioning of traditional Black Start providers non‑traditional technology in GB is connected (larger, synchronous power stations). The creation of to distribution networks and is much smaller smaller, distributed power islands is of particular interest in size than conventional Back Start provider as a result, whereby these would be initiated on distribution sites i.e. large synchronous power stations. networks and grow to energise the transmission network. This project has considered the technical capability of the As such, it is assumed that Black Start providers in future technologies, the challenges of creating and maintaining will not have to meet all of the technical requirements and small power islands with high penetrations of renewables services procured by National Grid ESO, but instead can and DER, and how to better predict the reliability and provide more discrete services along the restoration timeline availability of renewable generation in such a scenario. in accordance with their capabilities and strengths. The capability of the different technologies has been The project has three distinct deliverables: assessed according to their Shutdown Resilience • Report 1: Overview of the capability of non‑traditional Characteristics, their Black Start Performance and their technologies to provide Black Start and restoration Restoration Capabilities. services; The key findings from the technology capability • Report 2: Investigation of the challenges around power and readiness review are summarised as: system strength and stability specifically in relation to power islands with high penetrations of renewables • With the exception of EVs (which are not yet prolific and converter‑based technology; and enough to be considered viable in this context), all non‑traditional technologies investigated have • Report 3: A sophisticated planning tool specifically characteristics and capabilities that could be utilised designed to simulate distributions for the reliable output by National Grid ESO to support a Black Start and of wind over periods of hours to days, and how these restoration effort. distributions vary on timescales of months and years. • Much uncertainty surrounds the resource availability This report is Report 1, one of the three deliverables from of battery storage (state of charge at the time the “Black Start from Non‑Traditional Technologies” project. of shutdown) at the time of a Black Start but this The report outlines the existing Black Start technical can be improved through providing a route to market requirements set out by National Grid ESO and should for DER such that these sites are incentivised be reviewed in response to the evolving generation to ensure a minimum level of charge at all times. landscape in GB. • Similar concerns around the uncertainty of wind and solar resource are evident. Some of this uncertainty can be mitigated through better modelling tools (see Report 3) to increase confidence and provide a minimum level of assurance that this resource can or will be available as and when required. 02 03 National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration National Grid ESO | June 2019 Technology Capability and Readiness for Distributed Restoration 1 Introduction – Black Start in Great Britain Once this Power Island is established, the priority is The islands have an abundance of renewable resource, 1.1 Background to restore electrical supplies to other generators which 1.2 The evolving energy most prominently wind and wave/tidal, and they are Black Start is the process of restoring the National do not have Black Start capability by energising the landscape exploiting this to the fullest. The Orkney Isles are now Electricity Transmission System (NETS) following the transmission network. These generators then join this a net exporter of electrical power, a far cry from the highly unlikely, but highly impactful, event of a partial growing network to progressively restore demand across Over the past decade, the energy landscape in GB, previous status quo of reliance on importing fossil fuel or total shutdown. National Grid Electricity System the country until full restoration is achieved. and indeed in the majority of developed countries, generated power from the Scottish mainland. They have Operator (ESO) is responsible for ensuring there is an has changed
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