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Degradation Reference

Case

Miles Evans | EPRI

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Degradation Reference Case

▪ Based on CAISO Market case

– No ancillary services –just energy shifting

▪ Degradation is turned on

▪ Calendar degradationrate = 2%/yr

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Degradation Reference Case

▪ Enter an expected lifetime then compare the expected lifetime to the dynamic degradation results.

▪ Re-run the case with the dynamic degradation results as the expected lifetime. Repeat as necessary.

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Degradation Reference Case – Cycle Life Curve

▪ Each entry represents the number of cycles at that depth of discharge it would take to degrade the battery from its beginning of life to its end of life

▪ In json or command line, youcan change the EOL condition used to make this table. Default = 80%

▪ Default curve based on an aggregation of public LFP cycle life curves

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Degradation Reference Case – Cycle Life Curve

▪ This case contains a shorter-life cycle life curve than the default.

▪ Based on an older NMC cell

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Degradation Reference Case - Results

▪ …degradation_data.csv

▪ Labeling issue in columns B and C – look at column D

3750

3800

3850

3900

3950

4000

4050

0 50 100 150 200 250 300 350 400

Effe

ctiv

e En

ergy

Ca

pac

ity

(kW

h)

Day of the Year

Year-Ending SOH:95.1%

Implied lifetime:4.1 years

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Degradation Reference Case - Sensitivity

▪ Adjust variable O&M cost to suppress cycling

3800

3850

3900

3950

4000

1 6

11

16

21

26

31

36

41

46

51

56

61

66

71

76

81

86

91

96

101

106

111

116

121

126

131

136

141

146

151

156

161

166

171

176

181

186

191

196

201

206

211

216

221

226

231

236

241

246

251

256

261

266

271

276

281

286

291

296

301

306

311

316

321

326

331

336

341

346

351

356

361

366

Effe

ctiv

e En

ergy

Ca

pac

ity

Day of Year

$0/kWh $1/MWh $5/MWh $10/MWh $15/MWh $20/MWh $25/MWh $30/MWh $35/MWh $40/MWh $45/MWh

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Degradation Reference Case - Sensitivity

0

5

10

15

20

25

0 5 10 15 20 25 30 35 40 45 50

Life

(ye

ars)

Penalty ($/MWh)

40000

45000

50000

55000

60000

65000

70000

75000

80000

0 5 10 15 20 25 30 35 40 45 50

Year

ly V

alu

e ($

, yea

r 1

)

Penalty ($/MWh)

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Degradation Reference Case - Sensitivity

$0.00

$100,000.00

$200,000.00

$300,000.00

$400,000.00

$500,000.00

$600,000.00

0 5 10 15 20 25 30 35 40 45 50

Life

tim

e P

rese

nt

Val

ue

of

Ener

gy

Shif

tin

g ($

)

Penalty (M/kWh)

Lifetime Value Discount Rate = 7%

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Degradation Reference Case - Results

0

100

200

300

400

500

600

0 5 10 15 20 25 30 35 40 45 50

Equ

ival

ent

Cyc

les/

Year

Penalty ($/MWh)

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