Dr William Hung MBA, PhD, BSc, CEng FIET
System Technical SpecialistNational Grid
Managing the Future NationalTransmission System
– A Smarter Way
National Grid – The power of action
National Grid may have a good track record99.9999% Reliability
But,we are not complacent…
Learning from the past Planning for the future
Generation mixchallenges
Smart GridInnovations
Smarter EnergyBalancing
The Changing Generation Mix
05
10152025303540
GW
Gas
Coal
CCS
Wind
Other RenewableNuclearInterconnectors
Total Connected Generation (GW)
2010 2020 2030 2050
2020:
28GW of wind plus 9GW ofhydro, tidal, biomass
11GW nuclear available post2.5GW of closures and 3GWnew build
Demand remains flat - growth isoffset by energy efficiency andsmart metering
15 GW of embedded generation
2050:
30GW of nuclear now providesmajority of baseload generation
Increased demand withelectrification of
Transport (mainly during2030s)
Heat (growth from 2020)
The Network Challenge: ElectricityTransmission
future potential investment toconnect Scottish renewables
existing network
potential wind farm sites
future potential load relatedinvestment to 2017
potential nuclear sites
Gas CCGT Coal CCS
Nuclear Wind Renewable
Interconnector CHP Other
2010
2020
~75GW
~110GW
Anticipatory Investment in ElectricityTransmission
future potentialinvestment to connectScottish renewables
existing network
potential wind farmsites
future potential onshoreload related investment
potential nuclearsites
£4.7bn of proposedreinforcements
Programme of extrainvestment identifiedto March 2012
What are the Issues on FrequencyControl and System Security?
There will be an important role for Smart Demands
Challenges to System Frequency Control & Security of Supply
Maintain security and quality of supply standards
Economic purchase of Ancillary Services
System users/ service provider commitments Grid Code/CUSC/MSA
Transmission Licence Obligations
Closure of flexible and responsive plant(eg conventional coal, gas and oil stations)
New plants are less flexibility and less responsive(eg clean coal, supercritical boiler, IGCC, CCS,new nuclear)
Domination of wind farms – intermittency issues Secured generation loss – increase to 1800 MW
from 1320 MW Significant increase of small embedded
generation – less robust and invisible to SystemOperators
Future Challenges
Frequency control requirements Statutory 0.5 Hz, Operational 0.2 Hz & SD 0.07Hz
Cover instant generation loss of up to 1320 MW Avoid load disconnection - keep above 48.8 Hz 9 Stages of demand disconnection and up to 60%
Frequency Control Performance
Frequency Control/Wheel Pulling Analogy
Generators Vehicles
Frequency Wheel speedDemand level Slope gradientLoad variations Bumpy road
TV pickup Big rockLargest generation loss Largest truck stalledBlackout Wheel run away
Typical Frequency Incidents
49.20
49.30
49.40
49.50
49.60
49.70
49.80
49.90
50.00
50.10
12:2
4:00
12:2
5:00
12:2
6:00
12:2
7:00
12:2
8:00
12:2
9:00
Note:On this occasionGas Turbines startedat 12:29:20
Primary Response 0 - 30 secs
Secondary Response 30 secs - 30 mins
freqcont.ppt 009 24/02/99
Low Frequency Automatic DemandDisconnection Incident - 27th May 2008
48.6
48.8
49
49.2
49.4
49.6
49.8
50
50.2
50.4
11:3
0
11:3
1
11:3
2
11:3
3
11:3
4
11:3
5
11:3
6
11:3
7
11:3
8
11:3
9
11:4
0
11:4
1
11:4
2
11:4
3
11:4
4
11:4
5
11:4
6
11:4
7
11:4
8
11:4
9
11:5
0
11:5
1
11:5
2
11:5
3
11:5
4
11:5
5
11:5
6
11:5
7
11:5
8
11:5
9
12:0
0
Loss of 345MW generation
Loss of 1237MW generation
Loss of 40MW wind farmsand > 92MW embeddedgeneration
Further 279MW embeddedgeneration losses
Automatic low frequency relayDemand disconnection, 546MW
Demand Control
England ‘v’ Sweden (20th June 2006, 8pm)
System Operation – Exceptional Events
TV Pick Ups met using combination of coal plant,French Interconnector & pump storage hydro
Demand 20 June 2006England vs Sweden
36000
36500
37000
37500
38000
38500
39000
39500
19:5
0:00
19:5
2:00
19:5
4:00
19:5
6:00
19:5
8:00
20:0
0:00
20:0
2:00
20:0
4:00
20:0
6:00
20:0
8:00
20:1
0:00
20:1
2:00
20:1
4:00
20:1
6:00
20:1
8:00
20:2
0:00
20:2
2:00
20:2
4:00
20:2
6:00
20:2
8:00
20:3
0:00
20:3
2:00
20:3
4:00
20:3
6:00
20:3
8:00
20:4
0:00
20:4
2:00
20:4
4:00
20:4
6:00
20:4
8:00
20:5
0:00
20:5
2:00
20:5
4:00
20:5
6:00
20:5
8:00
21:0
0:00
21:0
2:00
21:0
4:00
21:0
6:00
21:0
8:00
21:1
0:00
21:1
2:00
21:1
4:00
21:1
6:00
21:1
8:00
21:2
0:00
21:2
2:00
21:2
4:00
21:2
6:00
21:2
8:00
21:3
0:00
21:3
2:00
21:3
4:00
21:3
6:00
21:3
8:00
21:4
0:00
21:4
2:00
21:4
4:00
21:4
6:00
21:4
8:00
21:5
0:00
21:5
2:00
21:5
4:00
21:5
6:00
21:5
8:00
22:0
0:00
Time (Local)
Dem
and M
W
20th June 2006 30th May 2006
Half Time1800MW
Full Time1600MW
The future is not certain . . .
CCS technologies need tobe ‘tested and proven’
Based on deterministic planning standards (NETS SQSS), supported by cost benefit analysis
At Peak Demand
0
1
2
3
4
5
6
7
8
2015 2016 2017 2018 2019 2020
Pow
er F
low
(GW
)
Range of Transfers across Anglo-Scottish (B6) Boundaryrequired to accommodate between 11.4 & 6GW of
renewable generation in Scotland
11.4GW
6GW
Current Boundary Capability
Programmed Reinforcements for 2011
Year
Schwarze pumpe CCS, Germany
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
1 3 5 7 9 11 13 15 17 19 21 23 25 27
MW
h
Wind Generation Demand
February 2006 wind & demand data
High pressure, low temperature period – higher gas demand
Whilst the extended low wind period is unusual, the general volatility is typical
Wind Intermittency
IntermittencyCreates Significant Challenges…
There will be an important role for Smart Demands
Challenges to System Balancing and Security of Supply
How reliable is renewable generation as asource?
How much conventional capacity can itdisplace?
What are the system integration cost andbenefits?
Generation Capacity Adequacy How much T&D capacity is required to
effectively transport renewable power?
Can the network operation philosophy bechanged to maximise the benefit ofrenewable generation
What are the costs and benefits of activenetwork management?
Transmission & Distribution Networks
What are the needs for flexible generation andresponse reserve capability? What are thecosts?
What are the benefits of having flexibledemands?
Real Time System Balancing
Transmission reinforcement aloneis not sufficient …
..Meters
An informativedisplay showingenergy utilisationand cost
Increases consumers’sensitivity to energy pricesand thus reduces demand.
..GridsAutomation andefficient use ofnetwork systems
Facilitates network flexibilityin a complex generationpattern
..DemandAutomation of loads inindustrial plants,commercial buildings,superstores and home
Facilitates demand sideresponse in a world of moreinflexible generation
Flexing generation tomeet demand
Flexing demand tomeet generation
Maximising capacity with smart..
Smart Demand meets Smart GridObjectives
Dynamic Demand and Active Demand SideManagement
Smart Grid = Paradigm shift in providing flexibility
From redundancy in assetsto more intelligentoperation throughincorporation of demandside and advancednetwork technologies insupport of real time gridmanagement
Source-HiDEF
The Future – Efficiency and Electrification
Electricity Heat Transport
Simple efficiencymeasures across
all sectorsAppliance efficiency Insulate homes
Efficient engines andintegrated transport
Decarbonisedelectricity fuels zero
emission vehicles Decarbonisedelectricity…
Heat pump
Mainly for new homesand decarbonisetransport
Decarbonise gasusing biomethane
BiomethaneCNG
Electrification of Transport and HeatPump Sectors
Value of Smart Demand – equivalent to a savingof almost 40GW of installed generation capacity
Source-HiDEF
Smart Fridges/Freezers – DisplacingPower Stations
Wind penetration
Cost savings £/FF/10yr
CO2 savings kg/FF/yr
Low High10-30
30-5015-3040-90
Source-HiDEF
Active Demand Side Management –Offset Wind Intermittency
WaterHeater HVAC
Generation flexibility
Cost savings £/kW/10yr
CO2 savings kg/kW/yr
High Low
3-15100-250<5075-100
Source-HiDEF
Operating the system in 2020
How to meet these challenges in the most economic andsustainable way whilst maintaining security of supply?
Active DistributionNetworks
SmartGrids &meters
GenerationDemand
Variable generation
Variable generation
Syntheticinertia
Distributed generation
ROCOF &Robustnessissues
Active Demand
30
35
40
45
50
55
60
00:0
0
01:0
0
02:0
0
03:0
0
04:0
0
05:0
0
06:0
0
07:0
0
08:0
0
09:0
0
10:0
0
11:0
0
12:0
0
13:0
0
14:0
0
15:0
0
16:0
0
17:0
0
18:0
0
19:0
0
20:0
0
21:0
0
22:0
0
23:0
0
Time of Day
Ele
ctri
city
Dem
and
(GW
)
2020 Demand ~ 15GWh (daily) - 1.5million vehicles
Typical winter dailydemand
Pea
k C
omm
utin
g Ti
me
12,000 miles p.a.
Pea
k C
omm
utin
g Ti
me
Optimal ChargingPeriod
Time of usetariffs
Inflexible generation
Variable generation
Large generation1800MW loss risk
What is a Smart Grid?
Two way communication - Sensing, automation andcontrol
Self Healing and resilient Asset optimisation Active power flow management Integration of renewable and distributed energy More reliable, more efficient networks
Customer Focused
Tools to engageconsumers with energy
efficiency
Network Focused
Integration of newsources of supply &
demand
Smart meters Improved information and awareness New energy services and tariffs Home automation & Demand response solutions More engaged, more efficient consumption
New Technology - to Make It Happen
All this has been used elsewhere, but not together in a densely meshednetwork
New technology is required to evolve the Transmission network andenable renewable generation
VSC Technology is still developing 2-3 year lead times for the larger cables Multi terminal HVDC has very limited
operational experience Control system optimisation
HVDC Wide area monitoring to control power
flows Dynamic circuit rating to manage
constraints Special protection schemes to facilitate
additional generation Automated control to manage complex
networks Congestion management control Opportunities to implement demand side
management
Smart Tools
Review of protection settings Sub-synchronous resonance Employed to control stability
Series capacitors
Warning - Uncontrolled Smart Demand couldJeopardise System Security
Balancing a system with significant volume of intermittent energy sources andincreased credible generation loss risk will require more flexible and smarterdemands to meet the renewable target and yet maintain the standards ofsecurity and quality of supply
An uncontrolled development of smart demands could jeopardise futuresystem security, for instance, fridges/freezers could provide frequency control,but under severe and sustained low frequency incidents they may jeopardisesystem frequency recovery as millions of f/f could cut in during this criticalperiod to maintain food integrity
Issues
Risks
Way ForwardNational Grid has been and will continue to work with the industry anduniversity researchers to provide expertise on future system needs and exploitthe potential of dynamic demands and active demand side management usinginnovative control techniques for future system frequency control and systembalancing purposes