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

Drivers for Change

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 Analogy

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

Can we ‘Predict and Provide’without a Smarter Grid?

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 – could helpto limit frequency fall

Source-RLTec

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

Conclusions

It is a Challenge and an Opportunity forNational Grid and other stakeholders

But,It need join up effort between

industry and government

GenerationMore flexible and

responsive

NetworkMore active and

intelligent

Demandsmarter and well

co-ordinated