Wind Power

Wind Installed in Ireland

Source: EirGrid

Projected installed capacity of wind in Ireland by 2020

Source: www.cer.ie CER/08/260 16th Dec 2008

Does Ireland have highest wind penetration in the world ?

US EU China India UK Nordic Ireland

Figures for end of 2007 in most casesSource: Global wind energy outlook 2008, www.eia.doe.gov , EirGrid, UK National Grid, NORDEL, Eurelectric

Does Ireland have highest wind penetration in the world ?

Figures for end of 2007 in most casesSource: Global wind energy outlook 2008, EirGrid, UK National Grid, NORDEL, Eurelectric

UCTE Nordic UK Ireland

Annual new wind capacity installed by region

Source: Global wind energy outlook 2008

UK projections

Source: www.national grid.com, seven year

Wind forecasting

Source: Bernhard Hasche

Wind forecasting

Source: P. Pinson

Extreme Sag?!

Research in Wind IntegrationWhy could Ireland lead the world ?

Research in Wind IntegrationWhy could Ireland lead the world ?

Europe

588,000MW

Nordic

85,000MWUK

78,000MWIreland

8,100MW

Didn’t update these - see newly added slides at start of presentation

Does Ireland have highest wind penetration in the world ?

Wind Capacity as a % of Installed Generation Capacity

7.28% 5.28%

7.58%

19.70%

1.08%1.52%

0%

5%

10%

15%

20%

25%

30%

35%

40%

UK Nordic Ireland Europe

Operational Contracted Applications

Didn’t update these - see newly added slides at start of presentation

Renewable Resources

Renewable ResourcesCost

Volume

The winner: Wind !

Wind installed worldwide

Wind Power

Why Wind Power

• Hydro is mostly fully developed and can have negative environmental impact

• Most viable form of renewable energy - economics • Good resource

– On land– Off shore

• Alternatives– Wave, photovoltaic, tidal, geothermal – technically challenging

and/or uneconomic– Biomass – economically marginal – space requirements

Extraction of Wind Energy

• Comes from sun - 174,423 TW

• How many hours is the energy equivalent to Ireland’s electrical energy consumption ?

• Less than 2% of radiated solar power converted into wind power

• Varies, difficult to predict

• Assume all kinetic energy is converted, power of wind calculated by product of mass flow rate with

• Continuity equation states• Total available power becomes

• In wind turbine, total available energy cannot be recovered – would require wind to stop completely, no flow through turbine

• - performance coefficient

wm2

2wv

w wm v

31

2w wP Av

pC

Energy capture efficiency

Energy capture efficiency

• For a wind turbine maximum• max = 0.59 • Generator and gearbox efficiency

• Ng = generator efficiency 80% or possibly more for a permanent magnet generator or grid-connected induction generator)

• Nb = gearbox/bearings efficiency (depends, could be as high as 95% if good)

pC

pC

31

2captured g b pP N N AC v

3

3 3

6 1 44 4

18 3 27P MW

31

2captured g b pP N N AC v

Question

A 4MW wind turbine generator has a cut in speed of 4 M/s and reaches its maximum power output at 18 M/s.

What is its power output at (a) 2 M/s(b) 6 M/s(c) 20 M/sIf the blade diameter was increased by 10 % recalculate the power output at 6M/s.

Solution

(a) 0 MW(b) We know power output at 18 M/s is 4MW at 1/3 speed i.e. 6 M/s all

other things being equal then as the relationship is cubic wrt speed then.

(c) At 20 M/s it is maxed out at 4MW – and may actually have cut out

If we increase the blade diameter by 10% we increase the cross sectional area A by (1.1)2 = 1.21 i.e. 21 % -

41.21*

27P MW

Harvesting: Supply demand balance

Harvesting renewables in Ireland

Consumer “demand” is a moving target

DAILY LOAD CURVES

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MW

19-Dec-06

18-Jul-06

Some Engineering: System Frequency Control

DAILY LOAD CURVES

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19-Dec-06

18-Jul-06

System Frequency Demand

Supply

Storage is €€€€€€

Demand

Supply

System Frequency

Frequency control: Ireland

DAILY LOAD CURVES

2000

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19-Dec-06

18-Jul-06

Wind Variability

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00 00:00

Half-hour

Win

d O

utp

ut

Day 5Day 13Day 14Day 15Day 26

Wind Power Forecasting

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 100 200 300 400Distance (km)

Corr

Coeff

0

0.05

0.1

0.15

0.2

0.25

0.3

0 6 12 18 24Forecast Horizon (hours)

Std

. D

ev.

of

For

ecas

t E

rror

Frequency Variations due to Wind

Frequency

49.75

49.8

49.85

49.9

49.95

50

50.05

50.1

50.15

50.2

0 600 1200 1800 2400 3000 3600 4200 4800 5400 6000 6600 7200 7800 8400 9000 9600

Time, sec

Hz

29-Sep-06 06-Oct-06

Blackout: Italy (5 % decline in system frequency)

3100

3200

3300

3400

3500

3600

3700

09:51:21 09:52:06 09:52:51 09:53:36 09:54:21 09:55:06 09:55:51

Time

MW

48.8

49

49.2

49.4

49.6

49.8

50

50.2

Hz

SYSTEM GENERATION RESERVE

FREQUENCY

Frequency control & reserve

Research Question

With large wind penetrations how much additional reserve is required to operate

the power system ?

Conceptual challenge

Wind Variation and Forecast Information

Load Variation and Forecast Information

Conventional GenerationInformation and OutageProbabilities

Required SystemReliability

Willingness toPay for Reliability

Probabilistic Calculations

, ,1 1 ,

,, , ,

1 1 1 ,

, ,1

1 1 1

1 1 1

1

G Gh

h i h i hi i total h

G GGh i h

i h j h j hi j j total h

j i j i

G

i h j hj

RPLSNO FOP POP

R PnafoFOP FOP POP

POP FOP

,,

1 1 ,

1 1GG

h i hj h

i j total hj i

R PnapoPOP

1,

2,

1, 2, ,

,

1,

2,

1, 2, ,

,

1:, ,.........

2:

1:, ,.........

2:

h h

h h

h h h h G h

G h h

h h

h h

h h G h

G h h

PLSFO PLSNO

PLSFO PLSNO

S PLSNO Hr FOP FOP FOP

PLSFO PLSNO

PLSPO PLSNO

PLSPO PLSNO

Hr POP POP POP

P

PL

LSPO PLSNO

System Reserve Requirements

Doherty, R. and O’Malley, M.J., “New approach to quantify reserve demand in systems with significant installed wind capacity”, IEEE Transactions on Power Systems”, Vol. 20, pp. 587 -595, 2005.

ILEX Energy, UCD, QUB and UMIST, “Operating reserve requirements as wind power penetration increases in the Irish electricity system”, Sustainable Energy Ireland, 2004.

Forecast errors

0%

2%

4%

6%

8%

10%

12%

14%

16%

18%

20%

0 MW 200MW

400MW

600MW

800MW

1000MW

1200MW

1400MW

1600MW

1800MW

2000MW

Installed Wind Capacity

Sta

nd

ard

dev

iati

on

of

win

d e

rro

r

Fast (1.25 min)

Slow (30 min)

1 Hour

4 Hour

Reserve targets

ILEX Energy, UCD, QUB and UMIST, “Operating reserve requirements as wind power penetration increases in the Irish electricity system”, Sustainable Energy Ireland, 2004.

250 MW

300 MW

350 MW

400 MW

450 MW

500 MW

550 MW

600 MW

650 MW

0 200 400 600 800 1000 1200 1400 1600 1800 2000

Re

ser

ve

Ta

rge

t

Installed Wind capacity (MW)

Fast (1.25 min)Slow (30 min)1 hour4 hour

Wind Capacity Credit

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0 500 1000 1500 2000 2500 3000 3500Wind Capacity (MW)

Cap

acity

Cre

dit

Gas Turbines NOx

Lean Premix

Wind power and emissions

Denny, E., and O’Malley, M.J., “Wind Generation, Power System Operation and Emissions Reduction” IEEE Transactions on Power Systems”, Vol. 21, pp. 341 – 347, 2006.

Portfolio Diversification: Plant mix

Is large scale storage a solution for wind ?

Research Question

Storage Economics Case # 1

850MW Wind, Capital cost storage, € 0 million/MWh

0

50

100

150

200

0 5000 10000 15000 20000 25000 30000 35000

MWh Storage

Pro

fit

€mill

ion

Storage Economics Case # 2

850MW Wind Capital Cost storage €0.1Milion/MWh

-150

-100

-50

0

50

100

150

0 5000 10000 15000 20000 25000 30000 35000

MWh Storage

Pro

fit

€m

illi

on

Storage Economics Case # 3

850MW Wind, Capital cost storage, € 0.5 million/MWh

-1400

-1200

-1000

-800

-600

-400

-200

0

200

0 5000 10000 15000 20000 25000 30000 35000

MWh Storage

Pro

fit

€m

illio

n

Turbines & pumpsTurbines & pumps

Upper reservoirUpper reservoir

Lower reservoirLower reservoir

Electrical energy stored as water at a height

Used for limited energy storage Limited resource Very fast reaction time

Pumped Storage (Turlough hill)

Research QuestionWill the slow inertial response

characteristics of wind turbine generators impact future power systems adversely?

Fixed speed wind turbine generator

Doubly fed inductiongenerator wind turbine

Synchronous generator

Does not add to system inertia

Mullane, A. and O’Malley, M.J., “The inertial-response of induction-machine based wind-turbines”, IEEE Transactions on Power Systems, Vol. 20, pp. 1496 – 1503, 2005.

Frequency

Frequency response

Lalor, G ., Ritchie, J., Flynn, D. and O’Malley, M.J., “The Impact of Combined Cycle Gas Turbine Short Term Dynamics on Frequency Control”, IEEE Transactions on Power Systems”, Vol. 20, pp. 1456 - 1464, 2005.

Lalor, G., Mullane, A., and O’Malley, M.J., “Frequency Control and Wind Turbine Technologies”, IEEE Transactions on Power Systems”, Vol. 20, pp. 1903 – 1913, 2005.

Harvesting: Network Issues

The Network Challenge

GeneratorsDemand

110kV

220kV

275kV

400kV

Interconnector

Network protests

A

B

C

Network Planning

Research QuestionWith large quantities of distributed

generation how do we use the existing networks in an optimal manner ?

Maximizing network as energy harvesting device

38kV 7 Bus Test System

1

max

[ (1 ) (1 )]

100 10%. ( )

.

.

N

DGi ji LDi jij

i i

Geni

i

Installed i DGi Avail i

Max P P

subject to

V V

P

SCL Cos

P P P

etc

i N

Constrained optimization problem

Keane, A and M.J. O’Malley, “Optimal Allocation of Embedded Generation on Distribution Networks”, IEEE Transactions on Power Systems”, Vol. 20, pp. 1640 - 1646, 2005.

15.50

19.74

41.00

0

5

10

15

20

25

30

35

40

P (

MW

)

Optimal 0.5%

curtailment

Base case 0%

curtailment

Optimal 0%

curtailment

Keane, A and M.J. O’Malley, “Optimal Allocation of Embedded Generation on Distribution Networks”, IEEE Transactions on Power Systems”, Vol. 20, pp. 1640 - 1646, 2005.

Keane, A. and M. J. O’Malley, “Optimal utilisation of distribution networks as energy harvesting devices”, IEEE Transactions on Power Systems”, Vol. 22, pp. 467 – 475, 2007.

Maximizing network as energy harvesting device

Supply demand balance: Why curtail wind ?

MW

Time

Night time Demand

“Must run level”

Wind generation + “must run level”

System Operator

Must curtail this wind to keep supply demand balance

Economics of Grid Integration Studies

What is the optimal amount of grid connected wind energy ?

Research Question

Costs and Benefits of Wind Power

Costs• Capital costs – economies of scale• Operation and Maintenance• Network Upgrade Costs • Reserve Cost• Cycling Cost

Benefits• Capacity• Emissions• Fuel saving

Net Benefits

5% of System Operating Costs

Denny, E. and O’Malley, M.J. “Quantifying the Total Net Benefits of Grid Integrated Wind”, IEEE Transactions on Power Systems, Vol. 22, no. 2, pp. 605 -615, 2007.

All Island Renewable Grid Study

Joint Steering Group• DETI, DCMNR, CER, NIAUR

Governance

Working Group•Dept. CENR•Dept. ETI•CER•Niaur•System Operator NI•EirGrid•Sustainable Energy Irl•Action Renewables•MO’M

Peer Review

Consultants•ESBI•Riso et al.•TNEI et al.•Ecofys

Appointment

WS1: Resource

WS2B: Supply Demand Balance

WS3: Network

WS4: Economic

Portfolio scenarios

Costs

Emissions savings

Stakeholder impact

WS2A: Screening

Geo-spread scenarios Costs

All-Island Renewable Grid Study- Overview

Worksteam (WS)

WS2A: Optimal renewable penetration

0

20

40

60

80

100

234567891011120

10

20

30

40

50

60

Carbon Price (€/Ton CO2)Gas Price (€/GJ)

Opt

iam

l Pen

etra

tion

of R

enew

able

Ene

rgy

(%)

Renewable Penetration

Portfolio 4

Gas Price – High

Carbon Price – Mean

WACC – Mean

Wind Costs – Normal

RE Benefits – 5 €/MWh

.Doherty, R and M.J. O’Malley, “Establishing the role that wind generation may have in future generation portfolios”, IEEE Transactions on Power Systems”, Vol. 21, pp. 1415 – 1422, 2006.

Concluding Remarks

Research in Wind IntegrationWhy could Ireland lead the world ?

Europe

588,000MW

Nordic

85,000MWUK

78,000MWIreland

8,100MW

Does Ireland have highest wind penetration in the world ?

Wind Capacity as a % of Installed Generation Capacity

7.28% 5.28%

7.58%

19.70%

1.08%1.52%

0%

5%

10%

15%

20%

25%

30%

35%

40%

UK Nordic Ireland Europe

Operational Contracted Applications