N. Keith Tovey, M.A. PhD, C.Eng MICE Н.К.Тови М.А., д-р технических...

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N. Keith Tovey, M.A. PhD, C.Eng MICE Н.К.Тови М.А., д-р технических наук

Energy Science DirectorLow Carbon Innovation Centre

University of East Anglia, Norwich

The changing face of the Electricity Market in the UKИзменяющееся лицо рынка электроэнергии в Британии

Руководитель по энергетическим исследованиям Центр экологических инноваций

Университет Восточной Англии, Норвич

Regulation in Electricity Supply

CLIMATE CHANGE GOVERNANCE AND COMPLIANCE

NBS-M017 2013

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Course WEB Page http://www2.env.uea.ac.uk/energy/energy.htm or http://www.uea.ac.uk/~e680/energy/energy.htm

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• A brief review of the UK Electricity Industry prior to 1990 under State Ownership.

– differences in approach between England / Wales and Scotland.

• Fuels used for generation

• Fuel Diversity – The Shannon-Wiener Index• The Electricity Markets in the 1990s after Privatisation • The New Electricity Trading Arrangements NETA (2001)• The British Electricity Trading and Transmission

Arrangements (BETTA).• The Supply of Electricity since 1990• Conclusions

The changing face of the Electricity Market in the UKИзменяющееся лицо рынка электроэнергии в Британии

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The Generation and Distribution of Electricity has always been different in Scotland compared to England and Wales

(Шотландия всегда отличалась от Англии и Уэльса в плане производства и распределения э/э )

Scotland Шотландия

Scotland (Шотландия):

Two vertically integrated companies supplying discrete

areas (Две вертикально интегрированных компании,

снабжающие отдельные территории)

England and Wales

Англия и Уэльс

England and Wales (Англия и Уэльс):

One Generating Company (CEGB) and 12 Regional

Electricity Suppliers

(Одна генерирующая компания (CEGB) и 12

региональных поставщиков).

EdF

Electricité de France EDF

2000 MW

Northern Ireland

Северная Ирландия

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Scottish Hydro

Scottish Power

Northern

Yorkshire

Eastern

London

East Midlands

SEEBOARDSWEB Southern

NORWEB

MANWEB

Midlands

SWALEC

Scotland

Шотландия

England & Wales

Англия

и Уэльс

Structure of Electricity Supply in early 1990s Структура

системы энергоснабжения в начале 1990 г.г.


Vertical Integration Вертикальная интеграция

• two companies две компании

England and Wales Англия и Уэльс

12 Regional Supply Companies 12 региональных компаний

also Distributed Network Operators а также распределяющие сетевые операторы

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Electricity Generation in the UK Производство электроэнергии в Великобритании

Until 2006, growth averaged 1.8% over previous 20 years

In recent years gas has overtaken coal as dominant fuel and nuclear has declined

Coal + Oil

Nuclear

Gas (CCGT)

Renewables

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Implications of daily/weekly/monthly variations in fuel use for Electricity Generation

The carbon factor for electricity generation in UK is ~ 540g/kWhVaries from

• Hour to hour• Day to day• Week to week• Month to month

• See

Current accounting only uses Grid annual average. In future accounting may relate to emissions associated with time of use Thus a heavy industry with high electricity demand in day time could significantly reduce its carbon emissions by operating overnight rather than during day.

www.bmreports.com

Daily fuel mix in electricity Generation11th January 2010

Weekly fuel mix in electricity Generation11 - 17th January 2010

Mon Tues Wed Thurs Fri Sat Sun

Notice higher proportion of coal used during day time hence a higher carbon emission factor.

• The Shannon-Weiner Index (H) is defined as:

H = - pI ln pI

where pi is the proportion of the ith fuel.

The index value increases with number of items and also the relative proportions of items

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Shannon – Wiener Index of Fuel Mix Diversity

With three fuels, the maximum value reaches 1.09 when all the fuels are in equal proportions.

In Norway where Hydro provides 99.5%, the index for the three fuels used is just 0.035.

Shannon – Wiener Index of Fuel Mix Diversity• Shannon – Wiener Index is a measure of diversity originally developed as a

measure of biodiversity.

• Higher index values occur with higher diversity.

• But there is no absolute upper limit.

• There is a maximum diversity index for a given number of fuels (e.g. species, fuels) when all items are in same proportion, but index will be higher for a greater number items.

• Index is low if one item dominates

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Variation in maximum value of Index with number of items. The situation occurs when all items have equal proportion.

e.g. with 6 fuel types the maximum value of index would be 1.8.

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Shannon – Wiener Index of Fuel Mix Diversity Exercise

Selected link for EXCEL Spreadsheet Template

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Transmission Network in the UK

Transmission throughout England, Wales and Scotland became unified on April 1st 2005

400 kV

275 kV

132 kV

Historically transmission networks have been different in England and Wales compared to Scotland

Исторически, сети передачи э/энергии в Англии и Уэльсе отличались от сетей Шотландии


England and Wales


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+1643

+7525

-4709

-1963

+418

Generating Capacity Surplus/Deficit

on February 12th 18:00

+ve: generating capacity exceeding demand

-ve: demand exceeding generating capacity

Most Generating Capacity is in the North - most demand is in South

MWInterconnector to Scotland

Interconnector to France

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• Decision on how electricity was to be generated was done on a generating set basis

• Generating Sets to run were selected on Merit Order.

• Based on Marginal Costs• (i.e. the fuel costs - цены на нефть)

Some generating sets were run OUT of MERIT ORDER where system constraints were an issue.

• Generators sold electricity to Regional Electricity Boards

• Electricity Boards sold to consumers in their Area only

• Prices to consumers varied between regions

Electricity Generation - pre 1990

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Central Electricity Generating BoardЦентральное

12 Regional Electricity Companies

•Coal (Угольные) Fired Power Stations

•Oil (Нефтяные) Fired Power stations

•Gas Turbine (Газовы турбины) Stations

• Hydro Stations (ГЭС)

•Nuclear Stations (Атомные)

•Transmission (Трансмиссия)

National Power

PowerGen

Nuclear Electric

National Grid Company

12 Regional Electricity Companies

Privatisation of Electricity Supply Industry 1990

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Typical UK Electricity Demand in Winter

2003 and 2005

0

10

20

30

40

50

60

0 24 48 72 96 120 144 168

GW

4th - 10th January 2003

11th - 17th January 2003

12th - 18th February 2005

Sat Sun Mon Tues Wed Thurs Fri

0

10

20

30

40

50

60

0 3 6 9 12 15 18 21 24

Hours

GW

4th January 2003

11th January 2003

16th February 2005

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Comparison of Demand Forecast and Outcome

Predicted and Actual Demand 27th - 28th September 2008

05

101520

253035

4045

0 6 12 18 24 30 36 42 48

time (hours)

GW

predicted

actual

Data for 48 hour period covering 27th and 28th September 2008

Note: there was an alert on 28th from period 45 (i.e. 22:30) meaning no actual data is available from this time.

Obtaining Information from BMREPORTS• Total Demand for electricity on a half hour basis may be

accessed from: www.bmreports.com

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INDO: Initial Demand Out-turn

ITSDO: Initial Transmission Demand Out-turn – includes transmission losses etc

What is today’s demand: What are today’s wholesale prices?

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• A brief review of the UK Electricity Industry prior to 1990. • The Electricity Markets in the 1990s after Privatisation

– the first system know as the “Pool”.– Some Countries operate a derivative of the “Pool”

• Operation of the Pool – the bidding Process

• The New Electricity Trading Arrangements NETA (2001)• The British Electricity Trading and Transmission Arrangements

(BETTA).• The Supply of Electricity since 1990• Conclusions

The changing face of the Electricity Market in the UK

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Eastern **

Industry-Промышленность

Independents-Независимые

Electricité de France

Innogy

Nuclear Electric *

BNFL (Magnox)

PowerGen

RECs

Licensed Suppliers

Лицензированные

поставщики

Consumers

Потребители

Second Tier

Consumers

Вторичные потребители

The

Pool

Пул

Scottish Nuclear

(Атомная) *

ConsumersПотребители

Scottish Hydro

Scottish Power ScotlandШотландия

England and Wales


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• Only the Generators (>100 MW) bid into the POOL to supply electricity e.g. National Power (now Innogy), PowerGen etc

• The National Grid Company published projected demands for the following day and invited bids

• The Generators supplied bids for each generating set in each station for each half-hour period of the following day

• The NGC sorted bids to determine which generating sets would be used for each particular period, and which ones would have capacity made available

The Operation of The Electricity Pool: 1990 – 2001

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Bid from company B £19.31 per MWh

Bid from company A £19.20 per MWh (0.96R / kWh)

Bid from company D £19.40 per MWhBid from company E £19.50 per MWh

Bid from company C £19.32 per MWh

Range of bids from companies in range £18 - £19 per MWh

0.90 - 0.95 Roubles per kWh

Range of bids from companies in range £15 - £18 per MWh

0.75 - 0.9 Roubles per kWh

Range of bids from companies in range <£15 per MWh

0.75 Roubles per kWh

10000 MW

10000 MW

10000 MW

1250 MW1250 MW

1250 MW1250 MW1250 MW

32500 MW

System Marginal

Price

= £19.31

SMP

Companies up to and

including B successful

£1 ~ 50 Roubles

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• All Companies who were successful were paid the SMP for all units generated irrespective of what their bid was

• The bids were for the single half-hour period and fresh bids were required for all half hour periods

• It was possible for companies to bid £0 and this would guarantee that they generated and paid SMP

– However, if all Companies did the same they would have to generate electricity for nothing

• In addition to the SMP, there was also a capacity charge relating to the generating capacity which was requested to be available

The Operation of The Electricity Pool

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• Capacity Charge paid to all Generators who had been requested to have capacity available.

-based on formula(по формуле): LOLP * (VOLL - SMP)

Loss of Load Probability

The Operation of The Electricity Pool

VOLL: was set by the Regulator at around £2400 per MWH

LOLP: normally a very low figure but could become significant if there was a shortfall in generating

Capacity Charge: signal to ensure sufficient capacity was available.

Pool Input Price (PIP) = SMP + LOLP * (VOLL - SMP)

Value of Lost Load

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•Some Power Stations constrained “ON” to ensure security of supply even when their bid was more expensive

(Некоторые электростанции constrained “ON” обеспечить снабжение, даже в случае более дорогих заявок)

•Some Power Stations constrained “OFF” even when their bid was cheaper (-excess of capacity in one region)

(Некоторые электростанции constrained “OFF” обеспечить снабжение, даже в случае более дешевых заявок)

•Constrained Stations paid their “Bid” Price (уплачивали их «заявочную» цену)

•POOL Output Price: (POP) = Pool Input Price + Uplift

•Uplift represented the additional charges incurred to National Grid Company because of System Constraints

•Suppliers purchased Electricity at Pool Output Price (Поставщики закупают э/э на Пуле по цене производителя)

Электрический пулSystem Constraints (Система давления):

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Электрический пул: A Review

Need for strong Regulatory Body to ensure prices were not fixed.

Evidence suggested price manipulation took place in early years.

Regulator required major generators to dispose of some stations.

The lack of Demand Side Bidding was a weakness Charges for Transmission Losses were averaged over

whole Network. •Customers in North subsidised those in South

•Generators in South subsidised those in North

• These issues have been partly resolved under BETTASeparate discussions relating to Distribution Charges are also under way

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Changes in Regional Electricity Companies in the 1990s

• Mergers

Scottish Hydro & Southern become Scottish & Southern

• Take-over

Scottish Power takes over MANWEB

• Vertical Integration

• nPower acquire Midlands

• PowerGen acquire East Midlands

• United Utilities formed

– in NORWEB areaPowerGen

nPower

United Utilities

Scottish & Southern

Scottish & Southern

Scottish

Power

Scottish

Power

1990

c. 1998

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• The New Electricity Trading Arrangements NETA (2001)• The British Electricity Trading and Transmission Arrangements

(BETTA).

– BETTA essentially extended NETA to cover Scotland.

– There were few changes in England and Wales apart from Transmission issues

– Operation of the Trading Market remained the same

– Although minor modification take place all the time

• In BETTA

• Both Generating and Demand Side Bidding Takes Place

• Most Electricity is traded outside Balancing Mechanism

• Favours those who guarantee specific levels of generation/supply in advance

• Favours those who can guarantee flexibility in output / demand at short notice.

The changing face of the Electricity Market in the UK

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The basic principles Основные принципы

Operation of BETTA

• Generators and Suppliers are penalised if they deviate from their agreed level of generation / supply.

• System security is maintained via the Balancing Mechanism

• Renewable Generators e.g. Wind and small CHP (~10 MW) can be adversely affected.

• Generation and Supply focuses on:

• Balancing Mechanism (BM) Units Generating BM Units: Demand BM Units Trading between Generating and Demand BM Units

– Only the volume traded ( not price) has to be notified.

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NETA/ BETTA The Balancing Mechanism: A Summary

Day Before Current Day

IPN FPN

Gate Closure

Real

Time

30

mins3.5 hours 1 hour

Operation of Balancing Mechanism

• Changes to contract position cannot be made after Gate Closure• Balancing Mechanism provides System Security

• Initial Physical Notification (IPN) – 24 hours in advance System Operator checks sufficient capacity is available.

• Final Physical Notification (FPN)

Gate Closure for Real Time Period of 30 mins Initially 3.5 hours before REAL Time later reduced to 1 hour.

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Generators and suppliers are penalised if they deviate from their contract position at the final physical notification (FPN).

The System Operator negotiates with balancing Mechanism (BM) units to increase/decrease the amount of electricity available to maintain system security and ensure system remains stable.

NETA/ BETTA: Operation of the The Balancing Mechanism:

• Case 1:

• Too little electricity on the system

– Generators can OFFER to INCREASE output

– Suppliers can OFFER to REDUCE consumption

Time

FPNOFFER Time

FPNOFFER

• If OFFER is agreed then Generators / Suppliers are PAID for any electricity increased / reduced under the OFFER.

Separate charges apply for these services.

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The Balancing Mechanism Балансирующий механизм

The New Electricity Trading Arrangements

Новая система оптовой торговли НЕТА

• To allow system to remain stable

• Too little electricity on the system

–Generators can OFFER to INCREASE output

–Suppliers can OFFER to REDUCE consumption

Time

FPNOFFER

Time

FPNOFFER

• If OFFER is agreed then Generators / Suppliers are PAID for any electricity increased / reduced under the OFFER.

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Case 2: Too much electricity on the system

The New Electricity Trading Arrangements

– Generators can BID to REDUCE output

– Suppliers can BID to INCREASE consumption

• If BID is agreed then Generators / Suppliers PAY for any reduction in generation / increase in demand under the BID.

Time

FPNOFFER

BidFPN

OFFER

Bid

Time

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The Balancing Mechanism: Offers and Bids

Generators / Suppliers may submit OFFERs or BIDs which differ for different levels of deviation from the Final Physical Notification

National Grid Company normally accepts OFFERS / BIDS which are cheapest unless System Constraints prevent this.

25 - 50 MW: £30 per MWh (1.5 Roubles per kWh)

50 - 100 MW: £50 per MWh (2.5 Roubles per kWh)

0 - 25 MW: £20 per MWh (1 Rouble per kWh) FPN окончательная физическая нотификация

Example of Differential Offers from a Generator

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What happens if System Operator has got it wrong?

• OFFERs / BIDs cannot be cancelled

• UNDO BID removes an OFFER and is usually less than the OFFER

• UNDO OFFER removes a BID and is usually more than the BID

• OFFERs / UNDO BIDs [ or BIDs / UNDO OFFERs] are submitted in pairs

OFFER / UNDO BID: Pair +2

OFFER / UNDO BID: Pair +1

BID / UNDO OFFER: Pair -1

BID / UNDO OFFER: Pair -2

FPN

The Balancing Mechanism: Undo Offers/Undo Bids

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FPNPaid SSP

FPN

Actual Metered Volume

Pays SBP

Charges for imbalance depend on whether BM unit is deviating in same direction as overall system or not.

Example shows cases where imbalance is in same direction as system

Установлено в двустороннем

порядке договаривающ

имися сторонами

Settled bilaterally between

contracting parties

Установлено в двустороннем порядке между

сторонами

Settled bilaterally between parties

Actual Metered Volume

The Balancing Mechanism: Imbalance Charges

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Regional Supply

Ownership

Distributed Network Ownership in 2004

Scottish & Southern

nPower

E.ON (PowerGen)


Distributed Network

Ownership Владение

распределительной сети

Distributed Network Ownership in 2005

In 2007, Scottish Power became part of Iberdrola

Scottish & Southern

United Utilities

CE Electric UK

Western Power

PowerGen

Aquila

Central Networks

Western Power

IberdrolaScottish Power


IberdrolaScottish Power

UKPower Networks

Distributed Network Ownership in 2010/11

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Changes when BETTA came into force – April 1st 2005• Integrated Trading System operating England and Wales with

Scotland

• Before BETTA– System and Transmission Network Operator in England and

Wales was National Grid Company (NGC).– System and Transmission Network Operator in South of

Scotland was Scottish Power– System and Transmission Network Operator in North of

Scotland was Scottish and Southern

• After BETTA– National Grid Company become System Operator for whole of

England, Wales and Scotland.– NGC now Transmission operator for England and Wales– In Scotland the two companies now hold the respective

transmission Network Licences– Issues of differences in Transmission Protocol had to be resolved –

including the use of the Inter connector– Charges for Transmission Losses had to be addressed

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Example of System Sell Price (SSP) and System Buy Price (SBP) corresponding with First Point of Triad 2010-2011.

Impact on System Sell and Buy Prices

Sunday 6th December 2010 Monday 7th December 2010

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How well has it performed since starting on 27th March 2001?

Wholesale prices rose rapidly in 2004/2005, fell sharply from mid 2006, rose rapidly since mid 2007 then fell but are less stable.

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UK becomes net importer of gas

Completion of Langeled Gas Line to Norway

Oil reaches $140 a barrel

Impact on Wholesale Charges

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2

5

B £20 to £25 per kW

25

26

G - £5 to £0 per kW

2327 H - £10 to -£5 per kW

Generator Connection Charges under BETTA Плата за подключение к

генератору энергоснабжения по BETTA

18 F £0 to £5 per kW

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21 22

17

1

A > £25 per kW

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12

D £10 to £15 per kW

11

10

7 9

C £15 to £20 per kW

8

613

19

14

16

20

15

E £5 to £10 per kW

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No. Zone Name Tariff (£/kW)

1 North Scotland 25.4189712 East Aberdeenshire 22.7951393 Western Highlands 26.1468954 Skye and Lochalsh 30.2519195 Eastern Grampian and Tayside 21.5460496 Central Grampian 19.7502087 Argyll 18.5155688 The Trossachs 16.4919229 Stirlingshire and Fife 16.40382510 South West Scotland 15.52981411 Lothian and Borders 12.83610812 Solway and Cheviot 11.07268513 North East England 8.64103214 North Lancashire and The Lakes 7.475188

Generation Connection Charges from April 1st 2013

Note: Updated Values on those in handout and current as of October 2013

These are general charges for each area in addition there are additional charges reflecting the capabilities of the local regions around each substation

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No. Zone Name Tariff (£/kW)15 South Lancashire, Yorkshire and Humber 6.34209216 North Midlands and North Wales 5.18403217 South Lincolnshire and North Norfolk 3.48647018 Mid Wales and The Midlands 2.44290919 Anglesey and Snowdon 7.40903920 Pembrokeshire 5.56612821 South Wales 2.91658822 Cotswold 0.03875623 Central London -4.44237224 Essex and Kent 0.19139725 Oxfordshire, Surrey and Sussex -1.69243726 Somerset and Wessex -3.04519327 West Devon and Cornwall -5.165609

Generation Connection Charges from April 1st 2013

In addition there is a local sub-station tariff which varies from as much as £+5.805051 per kW at Edinbane on Skye in the SHETL area to as little -£0.742416 per kW at Mark Hill in the SPTL area.

• Beware!!!!

• The TRIAD Approaches!!!

on 1st November!

What is the TRIAD?

A modified measure of peak demand over winter period

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Demand Connection Charges 2012 - 2013

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Demand Connection Charges 2012 - 2013

The Triad occurs in the period 1st November – 28th/29th February

It is the mean of the following:

1)The maximum demand in any one half hour in the above time period.

2)The second highest demand in any one half hour provided it is separated from (1) by at least 10 days.

3)The third highest demand in any one half hour period provided that it is separated from (1) and (2) by at least 10 days

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Demand Zone Name TRIAD Demand (£/kW)

Energy Consumed (p/kWh)

1 Northern Scotland 11.048877 1.515130

2 Southern Scotland 16.789820 2.362577

3 Northern 22.346537 3.079732

4 North West 25.184470 3.651462

5 Yorkshire 25.485035 3.508859

6 N Wales & Mersey 25.631093 3.665429

7 East Midlands 28.213308 3.956866

8 Midlands 29.201069 4.148986

9 Eastern 29.891866 4.153363

10 South Wales 27.541773 3.685374

11 South East 32.827362 4.564101

12 London 34.083066 4.601445

13 Southern 33.752057 4.741274

14 South Western 33.551731 4.598152

Demand Connection Charges from April 1st 2013

This table has updated figures for 1st October 2013

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Example how TRIAD charges can be mitigated

Peak demand occurs at time of TRIAD - form process workingShift process by say 2 hours will reduce the TRIAD charge by over 25% or £13628 - see handout

494949

N.K. Tovey (杜伟贤 ) M.A, PhD, CEng, MICE, CEnv Н.К.Тови М.А., д-р технических наук

Recipient of James Watt Gold Medal

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NBS-M017 2013

8. Regulated Power Zones and Smart Grids

CLIMATE CHANGE GOVERNANCE AND COMPLIANCE

• Transmission and Distribution Networks are critical to electricity security.

• Losses on line:

= I 2 R where I is the current and R is resistance

• the power transmitted P = V * I - V = voltage

– Typical UK domestic voltage - 240V

– European Voltage - 220V

– North American Voltage 110V

• These are nominal voltages and system must control voltages within a narrow band of this.

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REGULATED POWER ZONES

Voltage%loss relative to 240

V

240 100.0%

11000 0.047603%

33000 0.005289%

132000 0.000331%

400000 0.000036%

Losses are reduced by increasing voltage

• The consequence of resistive losses is that the transmission and distribution cables heat up and may typically be running at 50o C+

• As they heat up they expand and the cables will sag more at mid-span with a the possibility of a flashover.

• This means that there will be less sag when the cable temperature is lower – i.e. in winter and also in times of higher wind speeds when the cooling effect of the wind will be greatest.

There is thus a maximum power load that any cable can take and this limits the number of connections that can be made.

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A further problem with AC transmission is that current flows mostly through the skin with much of the cross section not used effectively.Unlike DC

Traditional way to allocate generation connections:• Order of application according to potential maximum connection

capacity up to total capacity of transmission/distribution line.• A safe approach which ensures that transmission/ distribution lines are

not overloaded.

BUT• May not make optimum use of transmission capacity.

Example:• Suppose a line has 2000 MW capacity – a typical 400 kV ciruit capcity• Order of connection allocations:

– Generator 1: 1000 MW – say with 2 x 500 MW sets– Generator 2: 500 MW– Generator 3: 500 MW – with 2 x 250 MW sets.

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• If all sets are generating – 2000MW i.e. capacity of line and no more sets can connect without the expense of transmission line upgrade.

• If generating sets are fossil fuel, then they may have a relatively high load factor and traditionally that has not been a problem.

• BUT if say one of Generator 1’s sets is not generating, only 1500 MW of the 2000 MW of the line capacity is used.

• BUT no new generators can connect as the inactive set may come back on line.

Grandfathering Rights53

REGULATED POWER ZONESGenerating Sets Total installed

capacity

Generator 1 2 x 500 MW 1000 MW



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Problem is exacerbated with generating plant of low load factor e.g. wind and was first identified in Orkney where significant renewable generation threatened to seriously overload distribution system.

Orkney is connected to mainland by 1 x 30 MW and 1 x 20 MW cable. A fossil fired power station on Flotta associated with the oil terminal must run for safety reasons typically around 4.5 MW.

Burgar Hill had historic rights of around 7 MW with the European Marine Energy Centre (EMEC) a further 7MW also in this category.

Thereafter there were several other wind developments which threatened to exceed total capacity of cables to mainland as it was assumed that one of the two cables might be out of action giving only a maximum potential connection capacity of 20 MW.

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Total Historic Generating Capacity ~ 18.5 MWMinimum Demand in Orkney ~ 7 MWCapacity of smaller cable to mainland ~ 20 MW

Maximum Generation on Orkney which would not overload single mainland cable is

27 MW – i.e 8.5 MW new capacity could be connected.

But EMEC capacity is often 0 MW, and rarely is Burgar Hill at its rated output.

If dynamic dispatch of generation capacity is used much more generation could be connected.

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REGULATED POWER ZONESEvaluate total system capability at any one time C = mainland connection capacity (i.e. 20 or 30 or 50 MW) + instantaneous demand on Orkney

Subtract from this those generating connection which have grandfathering rights, but only up to the amount of instantaneous generation (NOT maximum connection rights)

This gives maximum additional capacity which can be connected at that time.

If this also is done on a first application first served basis, it would be possible to connect much more renewable generation than otherwise possible.

However, it may mean that wind turbines at the end of the queue may not be able to generate when wind speed is optimum and returns on investment are best

57

REGULATED POWER ZONESSuppose C = 60 MW – i.e. both cables operating and demand is 10 MW

If Flotta output is 7 MW and EMEC is 7MW and Burgar Hill say 3.5 MW (i.e less than rated connection of 7MW as wind speed is low – i.e. instantaneous load factor is 50%)

Available additional connection is 60 – 17.5 i.e 42.5 MW

If this were take by additional Wind at 50% load factor then 85 MW of additional capacity could connect.

BUT if wind speed increased to rated speed of wind turbines, Burgar Hill would now be at 7 MW and available capacity would be 39 MW.

If all of this were as wind turbines at rated output (i.e. 100% load factor) only 39 MW could actually generate and 46 MW would have to shut down at the time they were most productive.

Consequence of Dynamic Regulation of Power Zone• More effective use of transmission/distribution cables is made• A greater proportion of renewable energy can be brought on line at an

earlier stage

BUT• Those connecting last may find return on investment poor.

Lincolnshire RPZ operates only to transmit power from offshore wind farm• Does not primarily address demand, but cooling effect on cables to

minimise sag• In winter – higher wind speeds – greater output capacity from wind

turbines• BUT weather is cooler and cooling effect of wind on cables is greater so

cables can transmit more

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ELECTRIC VEHICLES: Widespread deployment of electric vehicles could adversely affect the generation of electricity – leading to less effective use of generating capacity.

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SMART GRIDS – DYNAMIC REGULATION of DEMAND

Existing peak demand occurs around 17:00 the time when most people return home .

Owners would potentially would start charging their vehicles potentially exacerbating the load profileElectric Vehicle demand from Dave Openshaw

http://81.29.73.156/~eeegrdev99/uploads/DOCS/778-20100726131949.pdf

Electric Vehicles with Smart Charging

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Strategy 1:Unrestricted charging as per previous slide

Strategy 2:Encourage people not to charge between 17:00 and 21:00 with a reduced tariff. Assume 75% take this up~ would remove light green area.

Strategy 3:Discharge remaining store in car batteries to help existing peak. i.e. move green area to red – at further reduced tariff – example shows 25% of people adopting this.

HEAT Pumps: Widespread deployment of Heat Pumps would exacerbate electricity demand

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Heat Pump demand from Dave Openshaw

http://81.29.73.156/~eeegrdev99/uploads/DOCS/778-20100726131949.pdf

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There is a less “peaky” demand from heat pumps than electric vehicles because of thermal store benefits from under floor heating,

Use of an additional thermal store could help further to fill mid-day peak and lop peak morning and evening periods for charge overnight.

N. Keith Tovey, M.A. PhD, C.Eng MICE Н.К.Тови М.А., д-р технических...

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Transcript of N. Keith Tovey, M.A. PhD, C.Eng MICE Н.К.Тови М.А., д-р технических...