2001 South First Street Champaign, Illinois 61820 +1 (217) 384.6330 Davis Power Consultants...

2001 South First StreetChampaign, Illinois 61820+1 (217) 384.6330 Davis Power Consultants

Strategic Location of Renewable Generation Based

on Grid Reliability

PowerWorld Users’ Group MeetingNovember 2-3, 2005

The CALIFORNIA ENERGY COMMISSION and DAVIS POWER CONSULTANTS contributed to the development of this analysis.

2

Strategy

• Identify links between electricity needs in the future and available renewable resources.

• Optimize development and deployment of renewables based on their benefits to:– Electricity system– Environment– Local economies

• Develop a research tool that integrates spatial resource characteristics and planning analysis.

3

Objectives

• Investigate the extent to which renewable distributed electricity generation can help address transmission constraints

• Determine performance characteristics for generation, transmission and renewable technology

• Identify locations within system where sufficient renewable generation can effectively address transmission problems

4

Objectives

• We want to determine the impact of large-scale distributed projects on grid security.

• We need to:– Identify weak transmission elements and

define metrics that assess system security.

– Find locations where new generation would enhance the security of the grid.

– Combine maps of beneficial locations with maps of energy resources.

5

Methodology

• Simulation– Power Flow

– Contingency Analysis

• Security Metrics

• Results– Weak Elements

– Security Indices

– Visualization

6

Power flow Simulation

• Identify weak elements in the system by simulating impacts from lost transmission or capacity (NERC N-1 contingency)

• More importantly, can identify locations in system where new generation can provide grid reliability benefits.

7

Normal Operation Example

100 MW

50 MW

280 MW 187 MW

110 MW 40 Mvar

80 MW 30 Mvar

130 MW 40 Mvar

40 MW 20 Mvar

1.00 pu

1.01 pu

1.04 pu1.04 pu

1.04 pu

0.9930 pu1.05 pu

A

MVA

A

MVA

A

MVA

A

MVA

A

MVA A

MVA

A

MVA

A

MVA

67 MW

67 MW

33 MW 32 MW

57 MW 58 MW

21 MW

21 MW

66 MW 65 MW

11 MW

11 MW

23 MW

42 MW

43 MW 28 MW 29 MW

23 MW

23 MW

150 MW

200 MW 0 Mvar

200 MW 0 Mvar

A

MVA

29 MW 28 MW

OneThree

Four

Two

Five

Six Seven

23 MW

87%

A

MVA

82%

A

MVA

System does not have normal operation thermal violations

8

Contingency Example

100 MW

50 MW

280 MW 188 MW

110 MW 40 Mvar

80 MW 30 Mvar

130 MW 40 Mvar

40 MW 20 Mvar

1.00 pu

1.01 pu

1.04 pu1.04 pu

1.04 pu

0.9675 pu1.05 pu

A

MVA

A

MVA

A

MVA

A

MVAA

MVA

A

MVA 45 MW

45 MW

55 MW 53 MW

0 MW 0 MW

58 MW

56 MW

52 MW 51 MW

26 MW

25 MW

43 MW

36 MW

37 MW 24 MW 25 MW

30 MW

30 MW

150 MW

200 MW 0 Mvar

200 MW 0 Mvar

A

MVA

25 MW 24 MW

OneThree

Four

Two

Five

Six Seven

44 MW

83%

A

MVA

83%

A

MVA

95%

A

MVA

156%

A

MVA

Suppose there is a fault and this line is disconnected

Planning Solutions:New line to bus 3

OR New generation

at bus 3

Then this line getsoverloaded

(is a weak element)This is a serious problem for the

system

9

Contingency Analysis

• Security is determined by the ability of the system to withstand equipment failure.

• Weak elements are those that present overloads in the contingency conditions (congestion).

• Standard approach is to perform a single (N-1) contingency analysis simulation.

• A ranking method will be demonstrated to prioritize transmission planning.

10

Results Organized by Lines, then Contingencies

Sum each value-100 to find the Aggregate Percentage ContingencyOverload (APCO)

Then multiplyby limit to getthe Aggregate MW ContingencyOverload (AMWCO)

11

100 MW

50 MW

280 MW 187 MW

110 MW 40 Mvar

80 MW 30 Mvar

130 MW 40 Mvar

40 MW 20 Mvar

1.00 pu

1.01 pu

1.04 pu1.04 pu

1.04 pu

0.9930 pu1.05 pu

A

MVA

A

MVA

A

MVA

A

MVA

A

MVAA

MVA

A

MVA

A

MVA

67 MW

67 MW

33 MW 32 MW

57 MW 58 MW

21 MW

21 MW

66 MW 65 MW

11 MW

11 MW

23 MW

42 MW

43 MW 28 MW 29 MW

23 MW

23 MW

150 MW

200 MW 0 Mvar

200 MW 0 Mvar

A

MVA

29 MW 28 MW

OneThree

Four

Two

Five

Six Seven

23 MW

87%A

MVA

82%A

MVA

28211470

AMWCO

Weak Element Visualization

12

Determination of Good Locations

Overloaded Linein this direction

New Source

Sink

Transfer helps mitigate the overload by means

of a counter-flow

13


• Generation could be located to produce counter-flows that mitigate weak element contingency overloads.

• The new injection of power requires decreasing generation somewhere else.– A good assumption is that generation will be

decreased across the system or each control area using participation factors.

14

TLR for Normal Operation

• Need to know how the new generation at a certain bus will impact the flows in a transmission element.

→ Transmission Loading Relief (TLR)

→ Since a TLR is calculated for every bus, the TLR can be used to rank locations that would be beneficial for security.

,ΔMWFlow

TLRΔMWInjection

BRANCHBUS BRANCH

BUS

jki jk

i

15

Specify the weak transmission element

Specify the sink of the transfer

Sensitivities are calculated for each bus

16

TLR for Contingencies

• Need to consider contingencies

• Contingency Transmission Loading Relief (TLR) Sensitivity is the change in the flow of a line due to an injection at a bus assuming a contingency condition.

,, ,

ΔContMWFlowTLR

ΔMWInjectionBRANCH CONT

BUS BRANCH CONT

BUS

jk ci jk c

i

17


• Equivalent TLR (ETLR):

, ,

Overloaded Contingencies that Elements overloaded branch

,

Contingent Violations

ETLR = TLR

TLR

BUS BUS BRANCH CONT

BUS CONTVIOL

i i jk c

jkjk

i v

v

18


• Weighted TLR (WTLR) using post-contingency TLRs:

,

Contingent Violations

CODir

WTLR = TLRSysAMWCO

MWCO

CONTVIOL

CONTVIOLBUS BUS CONTVIOL

CONTVIOL

i i v

v v

vN

,

Branches

CODir

WTLR = TLRSysAMWCO

AMWCO

BRANCH

CONTBUS BUS BRANCH

BRANCH

jk

i i jk

jk jk

N

• Weighted TLR (WTLR) using base case TLRs:

19

Weighted TLR (WTLR)

• Complexity: A TLR is computed for each bus, to mitigate a weak element, under a contingency.

• We want a single “weighted” TLR for each bus.

Buses

Weak Elements

Contingencies

Buses

WTLR

20

Calculating WTLRs

• The contingency information (severity and number) of a weak element can be captured by calculating the Aggregate MW Contingency Overload (AMWCO).

• This effectively converts the cube to a table.

Buses

Weak Elements

Buses

Weak Elements

Contingencies

21

Calculating WTLRs

• Need to mitigate the weakest elements first

• Weight the TLR by the weakness of each element, which is given by the AMWCO.

Buses

Weak Elements

Buses

WTLR

22

Meaning of the WTLR

• A WTLR of 0.5 at a bus means that 1MW of new generation injected at the specific bus is likely to reduce 0.5 MW of overload in transmission elements during contingencies.

• Thus, if we inject new generation at high impact buses, re-dispatch the system, and rerun the contingencies, the overloads will decrease.

• Note that the units of the WTLR are:

[MW Contingency Overload]

[MW Installed]

23

Large Case Example

• Project for the California Energy Commission (CEC).– Needed to simulate N-1 contingencies (about

6,000 for California)

– Simulation developed for 2003, 2005, 2007 and 2017 summer peak cases.

– In 2003, there were 170 violating contingencies, 255 contingency violations, and 146 weak elements.

24

Process Overview

Power Flow Cases

Identify Weak

Elements

Evaluate Locations(WTLR)

GIS Overlay

Test Power Injections at Select

Locations

MARIPO SA

MAD ERA

FRESN O

MERCED

TULARE

KIN GS

MO N TERREY

SAN BEN ITO

SAN TA CLARASAN TA CRUZ

IN YO

MO N O

STAN ISLAUS

PWR 1PWR 1

PWR 1

TO ULUMN E

ALPIN E

CALAVERAS

AMAD O R

EL D O RAD O

SAN MATEO

ALAMED A

MARIN

CO N TRA CO STA

SAN JO AQ UIN

SACRAMEN TO

YO N O

SO LAN O

N APA

SO N O MA

LAKE

MEN D O CH IN O

CO LUSA

SUTTER

BUTTE

GLEN N

PLACER

N EVAD A

SIERRA

YUBA

PLUMAS

TEH AMA

TRIMITY

H UMBO LD TSH ASTA

LASSEN

MO D O C

SISKIYO U

D EL N O RTE

SAN LUIS O BISPO

KERN

SAN TA BARBARA

VEN TURA

LO S AN GELES

SAN BERN ARD IN O

RIVERSID E

IMPERIAL

SAN D IEGO

O RAN GE

25

Result: Weak Element Distribution

0

50

100

150

200

250

300

350

400

0 20 40 60 80 100 120 140 160 180 200 220 240

# Weak Elements

APCO 2003 2005 2007

Both number and weakness of elements increase with time

26

Identification of Weak Elements

2007 2017

The spatial distribution of weak elements seems to follow an identifiable pattern.

27

MARIPOSA

MADERA

FRESNO

MERCED

TULARE

KINGS

MONTERREY

SAN BENITO

SANTA CLARASANTA CRUZ

INYO

MONO

STANISLAUS

PWR 1PWR 1

PWR 1

TOULUMNE

ALPINE

CALAVERAS

AMADOR

EL DORADO

SAN MATEO

ALAMEDA

MARIN

CONTRA COSTA

SAN JOAQUIN

SACRAMENTO

YONO

SOLANO

NAPA

SONOMA

LAKE

MENDOCHINO

COLUSA

SUTTER

BUTTEGLENN

PLACER

NEVADA

SIERRA

YUBA

PLUMAS

TEHAMA

TRIMITY

HUMBOLDTSHASTA

LASSEN

MODOC

SISKIYOU

DEL NORTE

SAN LUIS OBISPO

KERN

SANTA BARBARA

VENTURA

LOS ANGELES

SAN BERNARDINO

RIVERSIDE

IMPERIAL

SAN DIEGO

ORANGE

Good Locations

New generation at green locations will tend to reduce the overloads.

New generation at red-yellow locations will tend to increase the overloads.

Note that higher imports would worsen system security.

28

Local WTLR Visualization

SAN MATEO

ALAMEDA

CONTRA COSTA

CASTROVL

CV BART

HICKS

JEFFERSN

LS PSTAS

MTCALF D

METCALF

METCALF

MTCALF E

MNTA VSA

MONTAVIS

MORAGA

MRAGA 1M

MRAGA 2M

MORAGA

MRAGA 3M

NEWARK F

NEWARK E

NEWARK E

NWK DIST

NEWARK D

NWRK 2 M

NEWARK D

MARTIN C

SANMATEO

SANMATEO

MARTIN C

SARATOGA

TESLA C

TESLA

TESLA E

TESLA JA

TESLA

TESLA JB

TESLA D

UAL COGN

SFIA

MILLBRAE

RAVENSWD

RAVENSWD

DMTAR_SL

SL BART SN LNDRO

JENNY

ALAMEDCT

OAK C115

STATIN L

WHISMAN

MOFT.FLD

LOCKHD 1

LOCKHD 2

S.L.A.C.

MT VIEW

STELLING

JARVIS

CRYOGEN

CYTE PMP

CMP EVRS

FREMNT

CLARMNT

LKWDBART

LKWD_JCT LAKEWD-M

LAKEWD-C

LK_REACT

SERRMNTE

EST PRTL

STATIN D

AMES BS2

AMES BS1 AMES J1B

AMES J1A

AMES DST

WOLFE

E. SHORE

EASTSHRE

EMBRCDRE

EMBRCDRD

LAWRENCE

ROSSTAP1

ROSSMOOR

ROSSTAP2

SANRAMON

TASSAJAR

TRACY

TRACY JC

TRACY

TRCY PMP

STATIN X

DLY CTYP

DALY CTY

GRANT

UCB SUB

UCB JCT1

CLY LNDG

SMATEO3M

STATIN J

ALTM MDW

OAKLND23

MFT.FD J

LCKHD J1

LCKHD J2

SLACTAP1

ADCC

TES JCT

TES SUB

FLOWIND2

JV ENTER

LLNL TAP

LLNLAB

LLNL

WND MSTR

DELTAPMP

VASONA

BELMONT

CLY LNG2

PLO ALTO

LONESTAR

SHREDDER

SHREDJCT

BAIR

JV BART

BAY MDWS

SFIA-MA

SHAWROAD

EST GRND

HNTRS PT

MISSON

LARKIN E

LARKIN F

LARKIN D

POTRERO

BAYSHOR1

BAYSHOR2

AMD JCT

A.M.D

APP MAT

PHLPS_JT

PHILLIPS

BRITTN

PIERCY

IBM-CTLE

IBM-BALY

IBM-HRRS

IBM-HR J

BAILY J3

BAILY J1 BAILY J2

EVRGRN 2

EVRGRN J EVRGRN 1

GILROY

MARKHM J

MARKHAM MARKHMJ2

SWIFT

STONE J

STONE

GEN ELEC

DIXON LD

MABURY

MABURY J

MCKEE

SN JSE A

SJ B E

SJ B F

EDENVALE

EDNVL J3 EDNVL J1

EL PATIO

TRIMBLE

NORTECH

MONTAGUE

ZNKER J1

ZANKER ZNKER J2

KIFER

SCOTT

FMC JCT

FMC

AGNEW

AGNEW J

MILPITAS

waksha j

WAUKESHA

ELLS GTY

KSSN-JC2

HJ HEINZ

TEICHERT

TH.E.DV.

NUMMI

DUMBARTN

MOCCASIN

OAKDLTID

TUOLUMN

CRTEZ

PINEER

HILMAR

MT EDEN

OWENSTAP

OWNBRKWY

CARTWRT

MARITIME

LEPRINO

SAFEWAY

OI GLASS

EBMUDGRY

FIBRJCT2

FIBRJCT1

FIBRBJCT

FIBREBRD

DOMTAR

AEC_TP2

AEC_JCT

SFWY_TP2

AEC_300

AEC_TP1

SFWY_TP1 GWFTRACY

OWENSTP1

OWENSTP2

TCHRTJCT

TCHRT_T2TCHRT_T1

TCY MP1

TCY MP2

TESTAB12

TRAMAX11

LS ESTRS

N_LVMORE

VINEYD_D

VINEYARD

SLACTAP2

EDESTAP1

EDES

EDS GRNT

ELPT_SJ1

ELPT_SJ2

LS ESTRS

NORTHERN

NUMI TAP

NUMI JCT

SANPAULA

UAL TAP

EL ELP11

EVRMTC21

LS NWK11

LS NWK12

LS NWK13

METLS 11

METLS 12

METLS 13

MORSTA11

MORSTA21

MORSTA31

MORSTA41

MTCEVR11

NEWNEW11

SANMAR11

SANMAR12

SANPIT11

SN ELP11

BURLNGME

CAL MEC

DUBLIN

WTLR

29

1.50

0.75

0.00

–0.75

–1.50

WTLR

Eastern Interconnection

30

Towards a Locational Value

• Determination of locations where new generation would enhance security needs to be combined with availability and economics of energy resources.

• Valuation requires monetizing the security benefits.

31


• GIS spatial analysis techniques are needed to determine feasible generation alternatives for each location in a large-scale system.

$MW cost of least-cost alternative i ijc g

Based on existing energy potential and technology, a least-cost alternative can be determined for each location.

32


• Units of WTLR are [AMWCO/MW installed].

• The security cost/benefit can be obtained as follows: – Assume WTLR is negative: Injection reduces the

AMWCO

$, ,MW

cos i i k i k i

benefits k ts k

Value B C s

$$

AMWCO AMWCOMW

i MWi

i

cs

WTLR

33

Security-Penetration Curves

• Once a set of proposed sites is defined, the effect of simultaneous distributed injections with different levels of penetration can be simulated using security-penetration curves.

• The effectiveness of the solution is affected for large injections due to:– Local transfer capability of the grid– Reversed flows

34

Security-Penetration Curves

0

2,000

4,000

6,000

8,000

10,000

12,000

0 650 1300 2000 New Generation

SysAMWCO in 2005

69

500

115

230

35

Policy Analysis

• A fundamental goal of integrated electricity systems is to ensure dependable supply to customers.

• This goal cannot be achieved if the system consistently exhibits overloaded elements and congestion.

• System AMWCO can be utilized to:– Evaluate system security for different seasons/years– Design policy goals regarding security

• Can use security-penetration curves

36

Policy Analysis

0

2000

4000

6000

8000

10000

12000

14000

0 250 500 750 1000 1250 1500 1750 2000

New Generation

AMWCO2007 2005 2003

Indicates how much generation is needed to maintain the currentlevel of reliability.Approx. 500MW every two years(at strategic locations)

NewGen

AMWCO

Indicates the effect of new generationApprox. -3.5 MWCO/MW Installed

37

Policy Analysis

0

2000

4000

6000

8000

10000

12000

14000

0 250 500 750 1000 1250 1500 1750 2000

New Generation

AMWCO2007 2005 2003

0

2000

4000

6000

8000

10000

12000

14000

0 250 500 750 1000 1250 1500 1750 2000

New Generation

AMWCO2007 2005 2003

Generation needed to maintain the current level of reliability.

Generation needed in the next two years (2005) to solve the problems by 2017. Approx. 950MW

7300

38

Integrated Model

Power Flow Model

Weak Element Ranking

Spatial Rep. of New Generation

Contingency Analysis

EnergyResources

Maps of Energy Potential

List of Proposed SitesSecurity Indices

Generation Expansion

Security-Penetration

Curves

WTLR Calculation

GIS Spatial Overlay

Transmission Expansion

TransmissionPolicy

Energy Policy

2001 South First Street Champaign, Illinois 61820 +1 (217) 384.6330 Davis Power Consultants...

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Transcript of 2001 South First Street Champaign, Illinois 61820 +1 (217) 384.6330 Davis Power Consultants...