Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019)

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Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019)

CSIR Energy Centre

CSIR Energy Centre Pretoria. 15 April 2019

v1.1

JARRAD WRIGHT

[email protected]

JOANNE CALITZ

[email protected]

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Key takeaways

A constrained power system meant South Africa had to loadshed again in Q1-2019

• The RSA power system again became constrained in Q1-2019 with Eskom needing to loadshed (Stage 4 at times)

• Causes of loadshedding have been cited as high unplanned plant failures on the thermal coal fleet, the loss of Cahora Bassa import from Mozambique followed by intensive use of diesel (at OCGTs) and water (at pumped storage schemes) which eventually depleted

¹

• This has been the most intensive loadshedding experienced in RSA with 595 GWh of load shed just in March 2019 of the total 769 GWh in Q1-2019 (there was 1325 GWh of loadshedding throughout 2015)

The utility-scale VRE fleet notably contributed to limit the extent of loadshedding in Q1-2019

• The utility-scale VRE fleet

²

contributed 2 975 GWh (5.3%) to the RSA power system in Q1-2019 with monthly contributions ranging from 4.9-6.0%, weekly contributions from 4.1-7.0% and daily contributions from 2.9-7.7%

• During loadshedding periods, the utility-scale VRE fleet contributed 357 GWh of the total 2975 GWh from VRE during Q1-2019 i.e. loadshedding could have increased from 769 GWh to 1126 GWh (a 46% increase)

• Instantaneous contributions from the VRE fleet during loadshedding periods was up to 2.3 GW i.e. without the VRE fleet, loadshedding stage 5 & 6 could have been envoked

1Department of Public Enterprises, UPDATE : ESKOM ELECTRICITY SUPPLY, 03 April 2019;

21.5 GW solar PV, 2.0 GW wind and 0.5 GW CSP (CSP is marginally dispatchable considering coupling with thermal storage) RSA = Republic of South Africa; VRE = variable renewable energy

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100 600

200 300 400

250

0 450

50 550

150 350 500

Apr- 18 21

6

Jul- 18 9 3

GWh of load shedding

306

164

122

5 42

Jan- 15

Feb- 19 200

Nov- 15 71

Feb- 15

36 36

Mar- 15

60

Nov- 18 122

156

77

Aug- 15 56 May-

15

Jul- 15

40 260

Jun- 15

84 19

Oct- 15

Dec- 15

Jan- 18

Aug- 18

384

Feb- 18

Mar- 18

May- 18

Sep- 18

15 Oct-

18 24

Jun- 18

106 32 Dec-

18 Jan-

19 36

54 190

Sep- 15

Mar- 19 63

283

Apr- 15

233 178

49 3

43 138

174 595

184

27 12

63

Stage 4 Stage 3 Stage 2 Stage 1

First 3 months of 2019 – most intensive loadshedding in March with 595 GWh of 769 GWh in 2019... 1325 GWh throughout 2015

Year 2015 2016 2017 2018 2019

Energy

(GWh)

1325 - - 192 769 Duration

(hours)

858 - - 127 272

Notes: Load shedding assumed to have taken place for the full hours in which it was implemented. Practically, load shedding (and the Stage) may occassionally change/end during a particular hour; Total GWh calculated assuming Stage 1 = 1 000 MW, Stage 2 = 2 000 MW, Stage 3 = 3 000 MW, Stage 4 = 4 000 MW Sources: Eskom Twitter account; Eskom se Push (mobile app); CSIR analysis

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Loadshedding in 2015 predominantly during high demand periods (day and evening peaks)… most recently in 2019 this has been day/night

Hour of the day -->

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Total

Jan 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Feb 0 0 0 0 0 0 0 0 8 10 10 10 10 14 14 14 14 14 14 14 14 14 0 0 174

Mar 13 13 13 13 13 13 13 13 19 30 31 32 33 33 33 34 34 34 34 34 34 34 29 13 595

No load shedding No load shedding 2015

2016 2017

2019 2018

Notes: Load shedding assumed to have taken place for the full hours in which it was implemented. Practically, load shedding (and the Stage) may occassionally change/end during a particular hour; Total GWh calculated assuming Stage 1 = 1 000 MW, Stage 2 = 2 000 MW, Stage 3 = 3 000 MW, Stage 4 = 4 000 MW Sources: Eskom Twitter account; Eskom se Push (mobile app); CSIR analysis

No

Loadshedding

Intensive loadshedding Loadshedding intensity (per year)

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5

100 450 100

BW 2 BW 4

BW 1 BW 3

100

BW 3.5 BW 4

Expedited

150 50 200 200 450

649 559

676 650

686

BW 2 BW 3 BW 3.5

BW 1 BW 4 BW 4

Expedited 787

1 362

650

415 591

398

BW 3.5 BW 3

BW 1 BW 2 BW 4 BW 4

Expedited 627

417 435

813

591

Supply Sources

Notes: RSA = Republic of South Africa. Wind excludes Eskom’s Sere wind farm (100 MW). BW = Bid Window. PPA = Power Purchase Agreement. BW 4 includes BW 4 additional.

Sources: Eskom; DoE IPP Office

Procured and operational capacity under RSA’s RE IPP Procurement Programme (REIPPPP) with only 100 MW of CSP added in Q1-2019

2078 MW 1479 MW

Capacity operational

(1 January 2019)

400 MW 2078 MW 1479 MW 500 MW

435

415 398

BW 4 BW 3

BW 2

BW 1 BW 3.5 BW 4

Expedited 627

417

813

591

649 559 787

676 650

686

BW 4 Expedited BW 2

BW 1 BW 3 BW 3.5

650 1 362

BW 4

200 100 450

100

BW 2 50

BW 4

BW 1 BW 3 BW 3.5 BW 4

Expedited

150 200 200 450

Capacity operational

(31 March 2019)

Solar PV procured, PPAs not signed yet Solar PV procured, PPAs signed

Solar PV operational

Wind procured, PPAs not signed yet

Wind operational Wind procured, PPAs signed

CSP procured, PPAs not signed yet CSP procured, PPAs signed CSP operational

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6

257 560

1 075

300 400 500

210

960

965

1 460

2 078 2 078 2 078

1 479

1 479 1 479 1 479

467

2018 3 857

2013 2015

3 139

2014 2016

200

2020 2 040

2017

3 957 4 057

2019 (Q1) 1 520

+1 053

+520

+1 094

+718 +100 +100

Wind Solar PV CSP Supply Sources

Notes: RSA = Republic of South Africa. Solar PV capacity = capacity at point of common coupling. Wind includes Eskom’s Sere wind farm (100 MW).

Sources: Eskom; DoE IPP Office

From 1 November 2013 to 31 March 2019, 2 078 MW of wind, 1 479 MW of large-scale solar PV and 500 MW of CSP became operational in RSA

Capacity operational

[MW]

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Notes: Wind includes Eskom’s Sere wind farm (100 MW). CSP energy measured from date when more than two CSP plant were commissioned.

Wind and solar PV energy excludes curtailment and is thus lower than actual wind and solar PV generation Sources: Eskom; DoE IPP Office

In Q1-2019 - 3.0 TWh of wind, solar PV and CSP energy was produced in RSA with estimates of over 12 TWh for 2019 expected

Supply Sources Annual energy produced

[TWh] 12.4

4.7

5.0

0.05

2013

6.5

1.1

2014

1.1

2.2

2.5 1.6

2015

2.6

3.7 0.01

9.0

2.2

0.5

2016

3.3

0.7

2017

3.3

6.9

1.0

9.4

2018

0.9 0.4

2019 2020

0.1

10.8

Wind

Estimate for rest of 2019

Solar PV

CSP

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8

176 121 137

649

485 503

337

273 294

0 100 200 300 400 500 600 700 800 900 1 000 1 100 1 200 1 300 1 400

Monthly electricity production in GWh

1 161

880 933

5.0%

6.0%

4.9%

Monthly electricity production of SA’s wind, solar PV and CSP fleet ranging from 4.9-6.0% (similar to previous year)

Solar PV Wind CSP

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Supply Sources

Note: Wind generation includes Eskom’s 100 MW Sere wind farm. CSP energy only measured from date when more than two CSP plant were commissioned.

Wind and solar PV energy excludes curtailment and is thus lower than actual wind and solar PV generation.

Sources: Eskom; CSIR Energy Centre analysis

Capacity operational (1 Jan-31 Mar)

2078 MW 1479 MW

500 MW

% of total system load

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Monthly electricity production from wind, solar PV, CSP, residual load and loadshedding impact in Q1-2019

0 18

2 10 20

4 6 8 12 14 16 22

19.3 Monthly electricity

production in TWh

18.2 16.8 18.2 17.9

19.8

Loadshedding Solar PV

Residual Load CSP Wind

Notes: Pumping load excluded. Wind generation includes Eskom’s 100 MW Sere wind farm.

Supply Sources

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Capacity operational (1 Jan-31 Mar)

2078 MW 1479 MW

500 MW

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10

0 50 100 150 200 250 300 350 400 450

13 22 37 40 43

Electricity production in GWh/week

1 4 7 10 16 19 25 28 31 34 46 49 52

5.9%

5.7%

6.9%

6.1%

4.5%

5.6%

4.5%

5.2%4.9%

5.8%

4.8%

4.1%

Weekly contribution from utility-scale RE in first 3 months of 2019 ranges from 4.1-6.9% of total system demand

Note: Design as per Fraunhofer ISE.

% of total system load

CSP Solar PV Wind Supply Sources 2078 MW 1479 MW Capacity operational

500 MW

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Weekly electricity production wind, solar PV, CSP, residual load and loadshedding in Q1-2019

0 500 1 000 1 500 2 000 2 500 3 000 3 500 4 000 4 500 5 000

1 40

Electricity production in GWh/week

4 7 10 13 16 19 22 25 28 31 34 37 43 46 49 52

Supply Sources

Note: Week 1 only 6 of 7 days; Design as per Fraunhofer ISE. Pumping load excluded.

Loadshedding

Wind CSP Solar PV Residual Load 2078 MW 1479 MW Capacity operational

500 MW

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For Jan-Mar 2019, electricity production from wind, solar PV and CSP was above 25 GWh/d 90% of the time with maximum of 48 GWh/d

0 5 10 15 20 25 30 35 40 45 50

Electricity production in GWh/day

Supply Sources

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Note: Design as per Fraunhofer ISE.Wind includes Eskom‘s Sere wind plant.

Wind Solar PV CSP 2078 MW 1479 MW Capacity operational (end of month)

400 MW

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Daily electricity production of between 543-666 GWh in Jan 2019 with VRE contributing 5-8%

0 100 200 300 400 500 600 700 800

21 GWh/day

7

3 4 15 17

1 2 5 6 8 9 10 11 12 13 14 16 18 19 20 22 23 24 25 26 27 28 29 30 31

CSP Solar PV Wind Residual Load

Loadshedding Supply

Sources 2078 MW 1479 MW Capacity operational (end of month)

Note: Design as per Fraunhofer ISE. Daily production excludes pumping load. Wind includes Sere.

400 MW

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Daily electricity production of between 593-672 GWh/d in Feb 2019, VRE supplied 3-6% of system demand and up to 7% of load was shed

0 100 200 300 400 500 600 700 800

2 30

GWh/day

24 28

15 13

1 3 4 5 6 7 8 9 10 11 12 14 16 17 18 19 20 21 22 23 25 26 27 29 31

Residual Load

Loadshedding Solar PV CSP Wind Supply Sources Capacity operational (end of month)

2078 MW 1479 MW

500 MW

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Daily electricity production of 538-658 GWh/d in Mar 2019, VRE contributed 3-7% everyday and up to 14% of load was shed

0 100 200 300 400 500 600 700 800

28 31

27 GWh/day

2

1 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 29 30

Solar PV CSP Wind

Loadshedding

Residual Load Supply Sources Capacity operational (end of month)

2078 MW 1479 MW

500 MW

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16 0.0 2.0

0.5 1.0 1.5 2.5 3.0 3.5 4.0

GW

CSP Solar PV Wind

Hourly VRE production in Jan 2019 shows periodic solar PV and CSP;

wind varies but contributes notably during evening peaks

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Supply Sources

Note: Design as per Fraunhofer ISE. Pumping load excluded.

2078 MW 1479 MW Capacity operational (end of month)

400 MW

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17 2.0 4.0

0.0 1.0 2.5

0.5 1.5 3.0 3.5

GW

Wind Solar PV CSP

Hourly VRE electricity production in Feb 2019 shows how loadshedding could have increased to Stage 5-6 without VRE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Supply Sources

500 MW

3 2 1

4

Loadshedding stage

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18 0.0 2.0 1.5 1.0 0.5 2.5 3.0 3.5 4.0

GW

Solar PV Wind CSP

Hourly VRE electricity production in Mar 2019 shows again how loadshedding could have increased to Stage 5-6 without VRE

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Supply Sources

500 MW

4 3 2 1

Loadshedding stage

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19 0 5 15 20

10 25 30 35 40

GW

Supply Sources

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Hourly electricity production in Jan 2019 highlighting role of VRE fleet

400 MW

Residual Load

Loadshedding

CSP Solar PV Wind

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20 0 5 30

15 10 20 25 35 40

GW

Loadshedding

Residual Load Solar PV Wind CSP

Hourly electricity production in Feb 2019 with 5 days of loadshedding

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Supply Sources

500 MW 5 days of

loadshedding

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21 15

0 5 10 20 40

25 30 35

GW

Loadshedding Wind

CSP Solar PV

Residual Load

Hourly electricity production in Mar 2019 with 10 days of loadshedding

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

Supply Sources

500 MW 10 days of

loadshedding

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22

0 20 30

2 14 16

4 6 28

8 12 26 22 24 32 34

18 36

10

Power in GW

Loadshedding Wind

PV CSP

Residual (Eskom)

Significant contribution from VRE during loadshedding in Feb 2019 – 103 GWh and a maximum inst. contribution of 2.0 GW

500 MW

System demand

Monday Tuesday Wednesday Thursday Friday Saturday Sunday

Week of 11-17 February 2019

Supply Sources

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23

10 14 18 22 26 34

0 28

20 32 30 36

16

2 4 6 8 12 24

Power in GW

Loadshedding PV

Residual (Eskom) Wind

CSP

Supply Sources

Similarly, VRE provided valuable capacity during loadshedding in March 2019 – 254 GWh and a maximum inst. contribution of 2.3 GW

System demand

Monday Tuesday Wednesday Thursday Friday Saturday Sunday

Week of 18-24 March 2019

500 MW

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24

LDC = Load Duration Curve; ¹When demand is >90% of peak demand;

VRE = variable renewable energy (solar PV, wind and CSP) Sources: Eskom; CSIR Energy Centre analysis

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200

10

0 2 18 16 22 20 34

14 12 26

8 38

6 30

4 32

24 28 36 40

Hours of the year (sorted) Power in GW

-1.1 GW

System demand (before loadshedding)

Residual demand

(after VRE & loadshedding) System demand

(after loadshedding)

VRE reduced peak by 1.1 GW & high demand hours notably;

loadshedding could have increased by as much as 46% without VRE

LDC (1 Jan – 31 Mar 2019)

With VRE fleet, peak demand was reduced by 1.1 GW.

1

But more importantly, high demand hours¹ were reduced from 730 hrs to 144 hrs.

2

1

2

357 GWh of 2975 GWh from VRE was during loadshedding between Jan-Mar 2019.

Without VRE, loadshedding would have been more severe, it could have increased by 46% from 769 GWh to 1126 GWh.

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Brief analysis of variable renewable energy contribution during loadshedding (Q1-2019)