Smart Energy and Smart Grids Future challenges and smart solutions for the electricity system UKERC Summer School Wyboston Lakes 7 July 2015 Dave Openshaw UK Power Networks Consumers Million 8.1 Service Area km² 29,250 Underground Network km 139,024 Overhead Network km 46,704 Energy Distributed TWh 84.8 Peak Demand GW 16.2 UK Power Networks holds three electricity distribution licences: EPN (serving the East of England) SPN (serving the South-East of England) and LPN serving the bulk of London 2011. UK Pow er Netw orks. All rights reserved 2 GB electricity system topology 132,000 volts 33,000 volts Wind farms 25,000 volts 400,000 and 275,000 volts Railway supplies Solar PV farms Distribution substation 11,000 volts Primary substation 400/230 volts 11,000 volts National Grid entry point exit point Distributed Generation I&C consumers SME consumers Domestic consumers Homes with Street furniture micro-generation • Electricity transmission is at 400kV or 275kV in England and Wales (also 132kV in Scotland) - typical electricity distribution voltages are 132kV, 66kV, 33kV, 11kV, 25kV (rail traction) and 400/230V • Major power stations, large offshore windfarms and European interconnectors are connected to the transmission system but renewable generation (mainly onshore wind and solar PV) and CHP is now increasingly being connected to distribution systems © 2011. 2011. UK UK Pow Power Networks. Al lrights rightsreserved reserved er Netw orks. All 3 Future challenges and smart solutions Context • The UK Carbon Plan • Future energy scenarios Implications for supply and demand • Future generation scenarios • DG and micro-generation scenarios • Demand growth scenarios • EV charging and heat pump demand scenarios Wider system implications • Frequency stability • Power quality • Voltage management Smart solutions • Smart metering • Smart grid solutions Overall implications for the electricity distribution business model • The evolution from passive to smart DNO • The transition from smart DNO to Distribution System Operator 2011. UK Pow er Netw orks. All rights reserved 4 Decarbonisation – the role for renewable generation, heat and transport • The Carbon Plan sets out how the UK will achieve decarbonisation within the framework of energy policy: to make the transition to a low carbon economy while maintaining energy security, and minimising costs to consumers • The UK renewable Energy Roadmap identifies a range of renewable generation technologies which will make a significant contribution to UK’s ‘15% by 2020’ renewable energy target • Renewable heat, heat pumps and electric vehicles will displace conventional fossil fuel based technologies and further contribute to UK’s decarbonisation targets • The UK Solar PV Strategy has the ambition of approaching 20GW of solar PV capacity early in the next decade (from 2020) 2011. UK Pow er Netw orks. All rights reserved 5 Future energy scenarios (National Grid) • National Grid has developed four energy scenarios which consider different futures for electricity • Gone Green, Slow Progression and Low Carbon Life all emphasise low carbon generation but whilst GG and SP assume large scale renewables, LCL assumes a greater contribution from micro-generation and DG • GG and LCL both assume significant growth in EVs but only GG assumes significant growth in heat pumps. Source – National Grid Future Energy Scenarios 2011. UK Pow er Netw orks. All rights reserved • No Progression reflects economic constraints on achieving decarbonisation ambitions 6 Implications for supply and demand 2011. UK Pow er Netw orks. All rights reserved 7 Future generation scenarios solar nuclear gas CCS offshore wind onshore wind 2011. UK Pow er Netw orks. All rights reserved interconnectors Source – National Grid Future Energy Scenarios 8 ‘Low Carbon Life’ DG and micro-generation projections Distributed generation with installed capacity above 1MW DG and micro-generation with installed capacity below 1MW • This scenario implies a major shift from centrally dispatched ‘synchronous’ generation to widely distributed - but intermittent - forms of generation 2011. UK Pow er Netw orks. All rights reserved Source – National Grid Future Energy Scenarios Scenario: Low Carbon Life 9 Penetration of renewable generation (example EPN network) • Significant areas of UK Power Networks’ EPN region are now approaching DG saturation levels • Across UKPN, accepted connection offers for DG developments >5MW have been received for: • Kings Lynn • Norwich • Peterborough - 2731MW of solar PV - 343MW of onshore wind • Cambridge • Ipswich - 605MW other • Luton • Aylesbury • Chelmsford • Tilbury © 2011. UK Power Networks. Al l rights reserved 10 Electricity demand scenarios • These charts show the wide variations in peak power demand and annual consumption under different scenarios • Low Carbon Life and Gone Green are characterised by significant demand increases but with different trajectories – albeit converging beyond 2025 • Under No and Slow progression, demand continues to fall with little or no recovery Source – National Grid Future Energy Scenarios 2011. UK Pow er Netw orks. All rights reserved 11 EV and heat pump demand Source – National Grid Future Energy Scenarios 2011. UK Pow er Netw orks. All rights reserved • Gone Green and Low Carbon Life project high exponential growth in EV demand • Gone Green projects a similar growth rate in heat pump demand • Under Slow and No Progression EV demand growth accelerates slowly 12 Wider system implications 2011. UK Pow er Netw orks. All rights reserved 13 Frequency stability challenges • Wind and solar PV generation has minimal short-run marginal cost of production and hence will always have higher ‘merit order’ than other generation technologies (even nuclear) • Hence under future low demand / high (wind and solar PV) generation scenarios, synchronous generation will be constrained off • In these circumstances, system inertia will be low resulting in reduced frequency stability (higher rate of change of frequency) • In the event of a major loss of infeed this will lead to an enhanced risk of frequency collapse leading to wide scale supply interruptions – including operation of low frequency demand disconnection relays Source – National Grid System Operability Framework 14 Power quality challenges • A further consequence of reduced synchronous generation is lower system strength • Under future low demand / high (wind and solar PV) generation scenarios system fault levels will decline well below current levels • This will lead to power quality challenges in the form of deeper and more prolonged voltage dips and increased harmonic distortion • A further effect will be a possible system resonance shift to lower order harmonics Source – National Grid System Operability Framework 2011. UK Pow er Netw orks. All rights reserved 15 Voltage management challenges • Reactive / real powwer ratios are declining – i.e. reactive exports at GSPs are falling faster than power exports • A number of possible reasons – e.g. increased cable capacitance, less reactive demand, energy efficient lighting (CfLs exporting VArs) and distribution connected solar PV • At many GSPs distribution networks are exporting VARs to the transmission system – in 2013 DNOs were net suppliers of reactive power to the transmission system for 39% of the time • REACT project (NG led with DNO support) is exploring reasons but no firm conclusions as yet • ENTSO-E Demand Connection Code may disallow VAr exports from Distribution to Transmission systems • If this trend continues, DNOs will need to develop more comprehensive voltage management techniques • The T&D interface is not unique – DNOs may begin to experience issues at each voltage transformation stage • HV/LV substations will be particularly challenged due to continued proliferation of rooftop solar PV Source – National Grid System Operability Framework 2011. UK Pow er Netw orks. All rights reserved 16 Smart solutions 2011. UK Pow er Netw orks. All rights reserved 17 Smart metering system Smart Electricity Meter Comms Hub In-Home Display Data via two communication service providers (CSP) and one data service provider (DSP) – each contracted to DCC CSPs - Arqiva (North) Telefonica (Midlands & South) Single licensed Data Communications Company (DCC) Capita DSP - GGI WAN technology: long range radio and GPRS Home area network (HAN) technology: 2.4GHz and 868MHz ZigBee Micro-generation (FIT) meter Consumer Access Devices / Smart Appliances Power status polling Load switch operation Messaging Power outage alerts Voltage level (hh avg. rms) Hi/Lo voltage alert Extreme Hi/Lo voltage alert Voltage sag/swell log MD (hh avg.) Network Operator 4Q hh profile Asset Management & Control Centre Network Operator Revenue Management D Flows DUoS charges DCC Central Hub HH consumption Messaging Tariff change etc. Suppliers • From DCC Live (2016) and up to completion of rollout (2020?) DNOs will have an increasingly comprehensive (and necessary) suite of LV network utilisation data – along with real-time power outage and power quality data • But processes and systems will be necessary to extract the benefits whilst meeting the licence obligation regarding protection of data privacy © 2011. UK Power Networks. Al l rights reserved 18 Smart grid solutions (example UKPN projects) UK Power Networks is developing and trailing a range of ‘smart grid’ solutions to the emerging low carbon challenges to our business. Some of these projects combine technological and commercial innovation to provide solutions not only to resolve local network challenges but also the wider GB system challenges 1. Low Carbon London - industrial & commercial demand side response 2. Low Carbon London – residential dynamic time-of-use tariff 3. Flexible Plug & Play Networks – smart grid and communications technologies and active network management to provide headroom for renewable DG 4. Smarter Network (electricity) Storage – distribution network and wider system support 5. KASM (Kent Active System Management) – management of a highly active network through a contingency analysis tool – minimising constraints on DG export 6. Fault Current Limiter – creating additional headroom for urban DG Further information on UK Power Networks’ smart grid projects can be found on our innovation website: http://innovation.ukpowernetworks.co.uk/innovation/en/ 2011. UK Pow er Netw orks. All rights reserved 19 Case Study 1 - Low Carbon London - I&C Demand Response The challenge • highly loaded substations • requirement to design to remain firm under n-1 • typically brief periods when substation is out of firm • extremely expensive and disruptive grid reinforcement 4 x 15MVA 33/11kV intact The opportunity I&C customers with flexible demand and/or standby generation • air cooling load, industrial scale refrigeration, supermarket lighting N-1 • Ideally dispatching post-fault and only when demand exceeds firm capacity (to minimise constraints on availability of DSR for other purposes – e.g. flexible STOR / DSBR) • obviating the need for costly and disruptive network reinforcement • maximising capability of DSR to provide whole-system benefits The LCL trial • 18MW of DSR - 77% generation, 23% demand turn-down - procured across 37 sites • Dependability assessed at 70 – 80% for generation, 54 – 64% for demand turn down • Sufficient confidence to defer £43m reinforcement for UKPN’s networks over ED1 2011. UK Pow er Netw orks. All rights reserved 20 I&C Demand Response required demand response for various demand characteristics Demand above firm capacity Firm capacity Potential DSR dispatch event Demand Note: DSR dispatch would normally occur only under unplanned network single circuit outage conditions – hence potential conflict with other calls on DSR (e.g. STOR) is small (esp. summer peaking substations) Source: Poyry – Low Carbon London Project – synergies and conflicts in the use of DSR for national and local issues 2011. UK Pow er Netw orks. All rights reserved 21 Case Study 2 Low Carbon London residential dynamic time-of-use tariff tariff Trial purpose: to investigate the network demand impact of dynamic ToU Tariffs designed to maximise usage of zero carbon / marginal cost generation ‘Economy Alert’ tariff details: • Designed by EDF Energy • 1100 trial participants (plus control group) • 12 month trial • Smart meters installed by EDF Energy • Emulating ‘wind following’ tariff • based on historic wind data • reflecting day-on-day and within day variation in generation output • Strong price (per kWh) signals • 67.20p HIGH • 11.76p NORMAL • 3.99p LOW • Min 24 hour notice • Message delivered via IHD with SMS option 2011. UK Pow er Netw orks. All rights reserved 22 Dynamic Time of Use Tariffs Results Default price Low price Mean DSR (kW) High price Household performance rank against measured DSR, by price band Rank of households 2011. UK Pow er Netw orks. All rights reserved 23 Dynamic Time of Use Tariffs Consumer behaviour insights • • • • As anticipated, ‘wet’ appliances appear to have the greatest flexibility Tariff complexity appears not to be an issue for most consumers Many appeared to welcome the organisational planning imposed by the day-ahead pricing notification In general, customers appear to be keen to participate in Time of Use tariffs Appliances for which households reported flexibility in avoiding high prices on the tariff 2011. UK Pow er Netw orks. All rights reserved 24 Case study 3 - Flexible Plug & Play Networks facilitating renewable generation The Challenge: • Generator dominated network • Additional wind and solar PV farms wishing to connect • Existing network constraints • Potentially prohibitive connection charges • Unacceptable delays in connection • Undermining business case for projects 2011. UK Pow er Netw orks. All rights reserved 25 Flexible Plug & Play Networks The Solution: • Dynamic line ratings • Active DG management • Quad booster • IEC 61850 communications • Innovative contracts – quotabased DG curtailment quad booster Current status: • 54.40MW of accepted offers (15 projects) within the trial area of which 24.75MW is now connected • Expected annual curtailment given anticipated diversity of output with current mix of generation ~2% radio mesh comms 2011. UK Pow er Netw orks. All rights reserved 26 Case study 4 - Smarter Network Storage grid-scale electrical energy storage (Leighton Buzzard) • 6MW / 10MWh Li Ion Battery • Installed adjacent to Leighton Buzzard 33/11kV substation • Restoring firm capacity to the substation and avoiding need for a 3rd 33kV circuit and 33/11kV transformer • Batteries charged during off-peak periods – available for dispatch in the event of an outage during a peak period Li Ion batteries Battery and power electronics enclosure • Market opportunities include: - Power Purchase Tolling Agreements with Suppliers - TRIAD avoidance - STOR and Fast Reserve service to the SO - Dynamic and Fast Frequency Response services to the SO 2011. UK Pow er Netw orks. All rights reserved 27 Smarter Network Storage leveraging the capability across the supply chain 2011. UK Pow er Netw orks. All rights reserved 28 Smarter Network Storage Functionality Peak Shaving SNS uses its stored energy to meet peak demand which reduces the load on the network. This defers the need for network reinforcement to meet peak demand. Frequency Regulation SNS can regulate the grid frequency through power exchanges. This assists National Grid in stabilising the frequency of the wider electricity system. Reactive Power Support SNS has 7.5MVAr of reactive power capability. Reactive power can improve power factor, reduce losses and support voltage levels on both the local network and wider system Reserve Tolling / Wholesale Market SNS provides reserve capacity and can be triggered remotely to export power. This assists National Grid in balancing electricity demand and supply. SNS can provide energy based on a given energy delivery profile. This can be used to manage imbalance risk and assist in hedging against peak electricity prices; including reducing TRIAD charges for Suppliers 2011. UK Pow er Netw orks. All rights reserved 29 Case study 5 – Kent Active System Management (KASM) 2011. UK Pow er Netw orks. All rights reserved • Network runs interconnected with NG transmission system • 650MW of connected generation (mainly wind) • 300MW additional generation seeking connection (mainly solar PV) • Two existing interconnectors (France 2GW and Netherlands 1GW) • Two additional interconnectors planned (1GW France and 1GW Belgium) 30 KASM - Contingency Analysis Tool • Multiple scenarios for variable generation export and interconnector flows • Parts of distribution network approaching reverse power limits • 34 contingency scenarios need to be analysed • Worse case scenarios surrounding minimum demand / maximum generation (no diversity) and unplanned outage • Need to be able to quickly determine generation constraint actions • Essential to have realtime monitoring and contingency analysis capability 2011. UK Pow er Netw orks. All rights reserved 31 Case study 6 - Short Circuit Level Management Features and benefits: • Fault Current Limiter (pre-saturated core) • HV fault current / voltage dip limiting • Maintaining low source impedance • Allowing greater penetration of DG 2011. UK Pow er Netw orks. All rights reserved 32 Implications for the electricity distribution business model 2011. UK Pow er Netw orks. All rights reserved 33 The current evolution from ‘passive’ to ‘smart’ DNO Traditional Distribution Network Operator Managing a Largely Passive Network Passive - Smart Transition Smart Distribution Network Operator Managing an Increasingly Smart Network Smart Grid Technologies to Support an Active Network Advanced Control Room Operating & Network Visualisation Systems Active Network Management Self- Reconfiguring Networks On-line Diagnostics PMUs Monitoring & State Estimation Advanced SCADA & Telecommunications Actively Dispatched DSR & DG Phase Shifting Transformers Network Connected Storage Fault Current Limiters Integrated Voltage & PF Control D-Stacoms & Switched Capacitors Voltage Regulators & Phase Balancers Dynamic Line & Plant Ratings Adaptive Protection Network Meshing & Soft NOPs 34 2011. UK Pow er Netw orks. All rights reserved The future evolution to Distribution System Operator Future Distribution System Operator Smart Distribution Network Operator Managing an Active Network and Supporting System Balancing Managing an Increasingly Smart Network Flexible Demand Smart Grid Technologies to Support an Active Network Demand Response DG Constraining on/off Contracts Distributed Storage Energy Storage Smart Appliances Air Cooling Heat Pumps Electric Vehicles DNO – DSO Transition Di s patchable Resources Balancing & Reserve Services Transmission SystemServices Operator Balancing & Reserve Suppliers & Intermediaries Ancillary Services System Balancing Frequency Control & Constraint Management Bid – Offer Acceptances Supplemental Balancing Reserve Demand Side Balancing Reserve Fast Reserve STOR / Flexible STOR Frequency Response Black Start Pre-Gate Closure Contacts Pre-Gate BM Unit Transactions Ancillary and Commercial Services Reactive power Commercial Aggregation Virtual Power Plants Demand Side Management Energy Efficiency Smart metering Commercial Building Energy Services Home Energy Services Flexible Tariffs 2011. UK Pow er Netw orks. All rights reserved Balancing & Reserve Services Customer Services 35 Thank you