GE Energy Asia Development Bank Wind Energy Grid Integration Workshop: Issues and Challenges for systems with high penetration of Wind Power Nicholas W

GE Energy

Asia Development BankWind Energy Grid Integration Workshop:

Issues and Challengesfor systems with high penetration of Wind PowerNicholas W. Miller

GE Energy ConsultingBeijingSeptember 22-23, 2013Disclaimer: The views expressed in this document are those of the author, and do not necessarily reflect the views and policies of the Asian Development Bank (ADB), its Board of Directors, or the governments they represent. ADB does not guarantee the accuracy of the data included in this document, and accept no responsibility for any consequence of their use. By making any designation or reference to a particular territory or geographical area, or by using the term “country” in this document, ADB does not intend to make any judgments as to the legal or other status of any territory or area.

Large Scale Integration – an introduction

3 Nicholas W. Miller, GE Energy

ConsultingADB Wind Integration Workshop

September 23-24, 2013

2004 New York3 GW Wind10% Peak

Load4% Energy

2005 Ontario15 GW Wind50% Peak

Load30% Energy

2006 California13 GW Wind3 GW Solar26% Peak

Load15% Energy

2007 Texas15 GW Wind25% Peak

Load17% Energy

2009 Western U.S.

72 GW Wind15 GW Solar50% Peak

Load27% Energy

2010 New England

12 GW Wind39% Peak

Load24% Energy

2008 Maui70 MW Wind39% Peak

Load25% Energy2010 Oahu500 MW Wind100 MW Solar55% Peak

Load25% Energy

GE’s Integration of Renewables Experience

PJM Study (underway)

96GW Wind22GW Solar30% Energy

Studies commissioned by utilities, commissions, ISOs...

• Examine feasibility of 100+ GW of new renewables

• Consider operability, costs, emissions, transmission

Need for fleet flexibility, new operating strategies and markets, transmission reinforcement, grid

friendly renewables

4Nicholas W. Miller, GE Energy Consulting

ADB Wind Integration WorkshopSeptember 23-24, 2013

Major Study Results :•Large interconnected power systems can

accommodate variable generation (Wind + Solar) penetration levels exceeding 30% of peak loads

•But not by doing more of the same…..

To reach higher levels of wind generation and other renewables:

•Get the infrastructure right

•And use it betterThe debate has changed: No longer: “Is it possible?”

Now: “How do we get there?”



Renewables (%)

EnablersS

yste

m C

ost

Impediments Enablers• Wind Forecasting• Flexible Thermal fleet

– Faster quick starts– Deeper turn-down– Faster ramps

• More spatial diversity of wind/solar

• Grid-friendly wind and solar• Demand response ancillary

services

Impediments• Lack of transmission• Lack of control area cooperation• Market rules / contracts

constraints• Unobservable DG – “behind the

fence”• Inflexible operation strategies

during light load & high risk periods

System CostUnserved Energy

Missing Wind/Solar Target

Higher Cost of Electricity

All grid can accommodate substantial levels of wind and solar power … There is

never a hard limit

Lessons Learned



-50 -40 -30 -20 -10 0 10 20 30 40 500

5

10

15

20

25

30

35

40

45

50

Farm power (MW per interval)

Fre

quen

cy (%

)

100MW Oahu + 200MW Lanai + 200MW Molokai

0.1% percentile (1min) = -12.27

0.1% percentile (5min) = -31.336

0.1% percentile (10min) = -49.305

Negative most (1min) = -22.479



99.9% percentile (1min) = 11.7685

99.9% percentile (5min) = 33.0615

99.9% percentile (10min) = 54.0865

Positive most (1min) = 22.5425



Interval = 1min

Interval = 5min

Interval = 10min

1 day1 min 1 hr 1 wk10 min1 sec

GovernorResponse

Governor Response Automatic

Generation Control

AGC Regulation Economic

DispatchEconomicDispatch

ArbitragePlanning

GovernorResponseInertiaInertia

Positive Sequence Load Flow (GE PSLFTM)

Interhour Renewables Variability AnalysisTM

Long-term Dynamic Simulations (AGC)TM

Multi-Area Production Simulation (GE MAPSTM)

GovernorResponseSupportVoltage

Statistical Wind Power Variability Assessments

-0.25 -0.2 -0.15 -0.1 -0.05 0 0.05 0.1 0.15 0.2 0.250

10

20

30

40

50

Power ramp (pu per interval)

Fre

quency

(%

)

0% percentile (10min) = -0.140% percentile (60min) = -0.450.1% percentile (10min) = -0.090.1% percentile (60min) = -0.27

99.9% percentile (10min) = 0.1099.9% percentile (60min) = 0.31100% percentile (10min) = 0.18100% percentile (60min) = 0.48

Interval = 10min

Interval = 60min

-150 -100 -50 0 50 100 1500

10

20

30

40

50

Power ramp (MW per interval)

Fre

quency

(%

)



Interval = 10min

Interval = 60min

2008

-0.25 -0.2 -0.15 -0.1 -0.05 0 0.05 0.1 0.15 0.2 0.250

10

20

30

40

50

Power ramp (pu per interval)

Fre

quency

(%

)



Interval = 10min

Interval = 60min

-150 -100 -50 0 50 100 1500

10

20

30

40

50

Power ramp (MW per interval)

Fre

quency

(%

)



Interval = 10min

Interval = 60min

2008

These tools are used together to identify, assess

and propose solutions for

managing the wind integration

challenges

A variety of tools across many timescales…Subhourly

7 Nicholas W. Miller, GE Energy

ConsultingADB Wind Integration Workshop


Western Wind & Solar StudyCan 35% wind and solar, by energy be integrated into the western United States?

Goal: Assess the operating impacts and economics of wind and solar

•How do local resources compare to remote, higher quality resources delivered by long distance transmission?

•Can balancing area cooperation help manage variability?

•Do we need more reserves?

•Do we need more storage?

•How does geographic diversity help?

•What is the value of forecasting? 30% wind5% solar

In Footprint

20% wind3% solar

Out of Footprint

Source: NREL Western Wind & Solar Integration StudyFinal report http://www.nrel.gov/docs/fy10osti/47434.pdf

Executive summary http://www.nrel.gov/docs/fy10osti/47781.pdf



Study Area Dispatch - Week of July 10th - No Wind

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

MON JUL 10 TUE JUL 11 WED JUL 12 THU JUL 13 FRI JUL 14 SAT JUL 15 SUN JUL 16

MW

Nuclear Steam Coal Wind

Solar CSP w/ Storage Solar PV Combined Cycle

Gas Turbine Pumped Storage Hydro Hydro

Study Area Dispatch - Week of July 10th - 10%R

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000


MW


0

10,000

20,000

30,000

40,000

50,000

60,000

70,000


MW


0

10,000

20,000

30,000

40,000

50,000

60,000

70,000


MW

Week of July 10th (Peak-Load Season)

No Wind

10% Wind Energy

20% Wind Energy

30% Wind Energy



Study Area Dispatch - Week of April 10th - 10%R

0

10,000

20,000

30,000

40,000

50,000

MON APR 10 TUE APR 11 WED APR 12 THU APR 13 FRI APR 14 SAT APR 15 SUN APR 16

MW

Study Area Dispatch - Week of April 10th - No Wind

0

10,000

20,000

30,000

40,000

50,000


MW

Nuclear Steam Coal Wind

Solar CSP w/ Storage Solar PV Combined Cycle

Gas Turbine Pumped Storage Hydro Hydro


0

10,000

20,000

30,000

40,000

50,000


MW


0

10,000

20,000

30,000

40,000

50,000


MW

Week of April 10th (Loads are lower, winds are higher)

Nicholas W. Miller, GE Energy ConsultingADB Wind Integration Workshop


Operating Cost

• As the penetration of wind increases, the system operating cost (production cost) decreases.

• The savings is not proportional to the penetration level of wind

– Diminishing returns with increased penetration

• Wind forecast accuracy is important to capture all operating cost savings from increased wind penetration.

– Forecast has substantial and increasing impact as penetration level increases



Operating Cost Savings ($M)

0

5,000

10,000

15,000

20,000

25,000

Pre R L 10 R L 20 R L 30 R

Sa

vin

gs

($

M)

Operating Cost Savings ($M)



Locational Marginal Price (LMP)

• Wind is assumed to enter the market as a “zero cost” price taker.

– Wind generation revenues are assumed to equal their LMP market value

• As the penetration of wind increases, the LMP decreases.

– The highest priced hours see the largest impact.

– With perfect forecast of wind, LMP decreases for all hours

– With State of Art forecast, LMP may increase at times due to forecast errors

LMP is a good way to look at operational economic, even without full locational power markets



Generation Revenue ($B) - WECC

0

20

40

60

80

100

120

No Wind Pre R L 10 R L 20 R L 30 R

Re

ve

nu

e (

$B

)

Renewable

Non-Renew

Generator Revenues forAll of WECC ($B)

No Wind ExistingWind

10% WindEnergy

30% WindEnergy

20% WindEnergy



Impact on other resources

Thermal (especially coal) cycling

Hydro operation

Inter-area cooperation



Total Number of Starts

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

No Wind Pre R L 10 R L 10 R L 20 R L 30 R

CC

ST-COAL

Total Number of Generator Startsfor Combined Cycle and Coal Plants



How do hydro constraints affect these results?

Cost if you dispatch hydro to load only, not net load

Cost increase if hydro output kept flat over the

year

Ope

ratin

g co

st in

crea

se (

$M)

Scheduling and dispatch of hydro AFTER wind saves operating costs



Operating Cost Savings ($B) - WECC - 2006

0

5

10

15

20

25

Pre P I 10 P I 20 P I 30 P Pre R I 10 R I 20 R I 2020 R I 30 R

Savin

gs (

$B

illio

ns)

P = perfect wind forecast R = state-of-art wind forecast

$20B in savings$88/MWh of

wind

Operating Cost Savings due to Wind Forecasts

$2B in savingsFor “perfect”

forecasts

At 30% renewable energy penetration, this system CAN NOT operate without

forecasts



Savings from better inter-area cooperation

Full inter-area cooperation

Partial cooperation



Wind Curtailment is reduced by cooperation

Full cooperationPart cooperation

Business-as-usual

Documents

GE Energy Asia Development Bank Wind Energy Grid Integration Workshop: Issues and Challenges for systems with high penetration of Wind Power Nicholas W