Power System Emergency - 6 March 2014 - · PDF filePower System Emergency - 6 March 2014 ......

Power System Emergency -6 March 2014

Brian Dames

Chief Executive

7 March 2014

2

Key Message

Overview of the Power Emergency Declaration

System Status

Understanding load shedding

Conclusion

3

Key Message

Overview of the Power Emergency

System Status


Conclusion

Key messages

• Eskom declared an emergency at 06:00 on 6 March 2014 and for the first time since 2008, implemented rotational load shedding at 08:00. The emergency was lifted at 22:00 on 6 March 2014 and load shedding stopped

• This was a painful yet necessary decision to protect the electricity power system from a total black-out. A total black-out would have significant consequences on the South African economy

• Eskom’s power stations are old and the system is tight. Any event impacting >1500MW, could have a significant impact on the availability of supply

• While we are committed to provide early warning, this was the earliest we could communicate as the system status changed rapidly in the early hours of the morning of 6 March 2014

• Eskom is in a better position than in 2008 to manage the situation.

- experience and knowledge of managing this complexity, appropriate emergency and communication protocols in place and open and transparent communication with stakeholders, including the media

• The system will remain tight up to the end of Summer and throughout Winter, until a substantial part of the build programme delivers capacity

• It remains important for all customers to maintain or achieve 10% electricity savings especially in the commercial, industrial and residential sectors. 4

2008 vs. 2014 load shedding

5

2008 2014

Communication of

system status

Inadequate pre-communication

of system constraints

-Pro-active communication (Quarterly

system updates, summer/winter comm’s)

- Improved communication with

customers, media and other stakeholders

Executive management

oversight (pre-incident)

Inadequate integration

between functions prior to the

incident

Executive team assigned, Emergency

command centre (ERCC) established,

weekly reviews, alignment with

shareholder

Country demand

reduction protocols

No country protocol in place National Code of Practice, based on multi-

stakeholder input, approved by NERSA

Load shedding (small

customers)

Schedules developed during

the critical constraint

Prepared and published by Eskom and

Metros before the emergency as per Code.

Load curtailment (large

customers)

No pre-agreement Signed curtailment agreements

Preparedness Limited exercises and tests. Regular operational and two national

multi-stakeholder exercises.

Visibility Limited visibility of key

processes

Detailed information via Generation and

Customer Nerve Centres & National

Control Help Desk

Declaration of an

emergency

Once system was nearing

instability.

In line with the National Code of Practice.

Coal supplies Unhealthy levels – on average

below ten days no wet coal

Healthy levels – on average at 45 days

Wet coal procedures in place

As a reminder - electricity usage in Summer and Winter…

Sept-March – Spring/Summer

‘Live Lightly’

• Table Mountain profile

• Constrained all day incl. from 5 - 9pm

• Air-conditioning, geysers & pool pumps

primarily impact demand

• Commercial, agricultural & residential

customers can make the biggest

difference

April-Aug – Autumn/Winter

‘Beat the Peak’

• Peak profile

• Constrained from 5pm – 9pm

• Electrical heating, geysers, & pool

pumps primarily impact demand

• Residential customers can make the

biggest difference as demand

increases in the evenings

20,000

22,000

24,000

26,000

28,000

30,000

32,000

34,000

36,000

38,000

23:00 02:00 05:00 08:00 11:00 14:00 17:00 20:00 23:00 02:00

MW Summer & Winter load profiles

Typical Winter Day

Winter Peak Profile

Summer flat (Table Mountain profile)

6

7

Key Message


System Status


Conclusion

Overview of events leading up to the emergency

• The already constrained power system was further impacted by the following

events:

- The continuous rain in the last few days resulted in poor coal quality

resulting in additional load losses at our power stations

- A rapid change on the system in the early hours of 6 March 2014, as we

lost additional units at our power stations (4 x Kendal, 1 x Majuba, 1 x

Grootvlei - 3320MW lost by 05:00).

- There was limited available generation at Drakensberg and Palmiet

- Eskom utilised all emergency reserves at its disposal:

- Open-cycle gas turbines were brought on-line

- Demand market participation (DMP) including Emergency from key

industrial customers were utilised

• Over and above the utilisation of emergency reserves there was a shortage

of 3000 MW at 08:00. To manage the frequency levels and to protect the

national system from total collapse, controlled load shedding was

implemented immediately and unavoidably at short notice.

• The stage 3 load shedding resulted in a 20% reduction in demand enabling

National Control to balance the system

8

Cross-border impact during an emergency

• During Eskom system emergencies the following applies to exports:

• All non-firm energy supplies are reduced to zero,

• All firm energy supplies are reduced by 10%,

• Trading Partners are required to enforce the 10% reduction on their customer

base,

• Trading Partners are required to utilize all their own generation capacity to the

maximum,

• Energy which may inadvertently be drawn out of the Eskom system is charged

at emergency generation rates,

• The interruptibility of the specific customer agreements is activated by

National Control as the system requires it.

9

Generation challenges

• Generally Eskom’s power stations are oldand are impacted by frequent break downs.Increased boiler tube leaks are the primaryreason behind generator outages. Outageslips and extensions have taken muchlonger than initially planned due to the stateof the plant when opened up for inspectionas well as some performance issues inexecution.

• Over this week, some power stations in theMpumalanga area were further challengeddue to the high, continuous rainfall over thepast eight days that impacted coal quality(wet coal). This severely impacted theirability to effectively handle and feed coal tothe boilers at the power stations

• The result is that key power stations in thearea are operating at additional reducedoutputs

Coal stockyard under water

Conveyor belt impacted by wet coal

10

Wet vs. dry coal stockyard

11

• Wet stockyard• Dry stockyard

Wet vs. dry coal on conveyors

12

Wet

Wet

Dry

Kendal sequence of events (1)

Wednesday

Experienced problems

handling wet fine coal.

Took load losses up to

400 MW from 21:00

Coal stock level above target at 56 days.

Have experienced consistent heavy rain since Friday last week

Wet fine coal

1

2

3

During shift change-over

fine and wet coal received

from opencast mine with low

delivery of dry coal from

underground mine.

Supplemented shortfall with

fine and wet coal from

stockpile. This makes handling

of coal on conveying plant

difficult - causing blockages

and incline conveyor belts

slipping

2014-03-07 14

2. Coal Handling Plant Overview

Kendal sequence of events (2)

15

Thursday

Trips due to empty coal

bunkers during early hours of

Thursday Unit six 01:22

Unit one 01:40

Unit two 02:26

Unit five 07:58

Units were

recovered during the

day by getting dryer,

coarser

underground coal

By 17:26 all

units at Kendal

back on load

4

56

Kendal coal stock yard

16

Coal stock yard 1.3 km x

800 m

By having a robust

supply plan for all our

primary energy

resources, able to face

and recover from:

Wet coal management initiatives since 2008

Infrastructure Process Measurement and

Control

Guided flow chutes at

Duvha

Adequate coal stockpile

holding

Annual rain season

readiness audit for power

stations

Staithe bypass

conveyors

5 day coarse coal

stockpile at critical

stations

External rain season

audit of mines

Wet coal management

procedures per station

Review of management

and operating

procedures

Initiatives investigated but not implemented due to cost constraints

Re-claimers Covered stockpiles Additives

• Conveyor fire incident in December 2013 resulted in total supply to Duvha being sourced via road transport

• Middelburg Mining Services (MMS) constrained to supply full volume due to infrastructure and process flow

• Additional volumes available from MMS North Plant, however road construction and associated safety risk makes supply infeasible

• Additional coal supply sourced from various short term sources

• Feed to station constrained by current weather conditions

• Weather conditions impacting on return to service of conveyor system

• Supply in the latter part of March 2014

Duvha Power Station Coal Supply Constraints

Coal stocks at sufficient levels

Actual Stock days F2008, F2012, F2013 vs YTD Actual F2014

19

25 2522

20 19 1817 18

15

1213 13

4039 39

3638

41 4144 43

4139 3938

3940 42

43 4445

47 4748

494748

51 50 5152

5456 55

48

45 46

0

10

20

30

40

50

60

APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR

Sto

ck d

ays

Months

2007/8 2011/12 2012/13 2013/14

• Current coal stock piles are at healthy levels, in average of 45 days.

• Power stations that are highly dependent on road deliveries like Grootvlei, Komati and Tutuka stock days

have dropped below alarm level in February mainly due to mine and road deliveries slow ramp up after

the festive period , social unrest around specific routes and rain.

• Duvha Power Station stock days dropped due to the conveyor fire, but are being maintained around 14

days

• In anticipation of long duration rainfall, strategic stockpiles are set aside for such situations. However,

given the duration of this rainfall period these strategic stockpiles have been depleted.

Open cycle gas turbines

• Costly liquid fuelled gas turbines in the Western Cape continue to be used during the day, as an emergency resource, to meet the required demand

• Very expensive

• We are currently managing the utilisation of these units to safeguard fuel levels

Ankerlig Gourikwa

20

21

Key Message


System Status


Conclusion

February 2014 compared to February 2013

• There is an average difference between 1000 MW and 2200 MW over peak periods

• IPP supply expired Dec 2013

2014-03-07 22

4 – 5 February 2013, 10 – 11 February 2014 (Monday – Tuesday)

2014

2013

Difference

Available capacity to meet demand

23

• The emergency of 20 and 21 February 2014 was particularly tight from the

Thursday afternoon and into the Friday afternoon.

• A substantial change can be seen on the emergency of the 6th March when

the available capacity was much lower than the entire day’s demand

Emergency declared

Emergency declared

4 Kendal units lost

Prognosis for the next two weeks

• Rainy weather conditions are

forecast until the beginning of

next week

• Any small change on the system

could have a significant impact:

risks include fuel shortages,

increased plant maintenance

• This plan considers a forced

outage allowance of 6500 MW.

This does not cater for

significant events such as those

experienced this week which will

result in much tighter operations

and reliance on emergency

reserves.

24

Prognosis for the next two months

• The risk of emergency conditions

developing remains with us for the rest of

March and into April.

• From a planning perspective, the

unplanned outages are expected to

reduce as we go into winter.

• Planning is consistently in the “red” which

makes us extremely vulnerable to any

unforeseen events.

• Koeberg unit 2 is scheduled to come out

of service for planned maintenance in the

third week of March.

• Decision on license agreements on Kriel

PS expected in the latter part of March

201425

Supply-side: Renewable IPPs gain momentum

• The Department of Energy introduced three bid windows for the Renewable Independent Power Purchase Programme

• Of the 19 Renewable IPPs connected to the grid, 3 projects (99 MW) have achieved their contractual Commercial Operation Date (COD) and 8 projects are generating Early Operating Energy. Expect the last project of Bid Window 1 by no later than the first half of 2015

Bid Date MW Power

Purchase

Agreements

Type of Technology Status

(As at 21 February 2014)

1 5 Nov. 2012 1416 28 Wind, Solar PV,

Solar CSP

- 19 of 28 connected

- 3 projects achieved

COD; 8 projects in

Early Operating

- Last plant commercial

expected by Feb 2015

2 9 May 2013 1044 19 Wind, Solar PV,

Solar CSP, Landfill &

Biomass

- Progressing well

3 - Bid Window

3 still to be

concluded

17 bidders for 1456 MW - Wind, Solar PV, Solar CSP, Landfill and

Biomass technology

26

Supply-side: Cross-border IPPs

• Only until recently was Eskom allowed to conclude power purchase agreements with regional independent power producers

• While Eskom is committed to use IPPs, most contracts could not be concluded due to high price expectation

•

27

Project Type Potential Eskom

off-take

Status

Kudu Natural

gas

800 MW 600 MW Eskom spent substantial time negotiating.

PPA could not be concluded due to price

Mmamabula Coal 1 200 MW 900 MW • IG MOU signed

• Due to high price expectation could not be

signed

• Explicit linkage to coal price which was

higher than the Eskom coal cost

• New regulations implemented in RSA

making the DoE the procurer

Zesco Coal and

Hydro

200 MW 200 MW Could not be concluded due to high price

expectation

Kariba South Hydro 120 MW 50 MW Could not be concluded due to high price

expectation

Continued progress with New Build …

• Eskom is committed to completing the

new build programme and has put the

necessary resources in place to do so

• Work has resumed at Ingula pumped-

storage scheme after the safety incident

• Medupi and Kusile continue to

demonstrate world-class safety

performance (0.1 lost time incident rate).

Medupi’s first unit is still expected to be

synchronised in the second half of 2014

and Kusile’s first unit following a year

thereafter.

• The technical C&I issues at both Kusile

and Medupi are being addressed with the

on-boarding of Siemens.

28

Continued Progress with New Build

• Seven of the 46 wind-turbines at Sere PS are complete and the station’s 100MW is expected to be commissioned by 2014/2015

• Transmission power line construction is progressing well, major sections of the power grid (Western Cape, Limpopo and Gauteng) have been strengthened, although challenges still remain in terms of servitude acquisition.

29

30

Key Message


System Status


Conclusion

Balancing supply & demand

49.5 Hz

50.0 Hz

51.5 Hz

Generation Load

• Electricity demand must be matched in real time.

• Any mismatch in supply and demand is reflected in the system frequency.

• Strict frequency control is required in order to ensure system security.

• This requires 24/7/365 management of the integrated power system.

• This is a primary role of the System Operator (National Control)

31

Declaring a power emergency – NRS048

32

• On days when Eskom needs to reduce demand still further, afterutilising emergency reserves, the NRS048 protocol indicates thatEskom can declare a power emergency in order to protect the systemfrom a total blackout or collapse

• It does this by instructing key industrial customers to reduce load by10%.

• When all options have been exhausted, and if the demand stillexceeds available supply, Eskom initiates rotational load shedding.

• This is a scheduled process and is a controlled way of sharing theavailable electricity between all customers. By switching off parts ofthe network in a planned and controlled manner throughout the day,the system remains stable, and the impact is spread over a wider baseof customers.

Emergency demand reduction

• Demand reduction is executed in Stages.

• Each stage provides a given amount of demand depending on the season and time of day.

• The System Operator (National Control) determines the capacity shortfall and instructs the relevant stage of shedding to Eskom’s Top Customer division and Eskom’s Distribution control rooms.

• These control rooms in turn instruct the metros and municipalities to prepare for and implement load shedding.

• Procedures are in place to engage critical loads as defined in the Code of Practice (e.g. hospitals, airports, stadiums etc). These cannot all be kept off the schedules and therefore the necessity that these services keep back-up generators

33

Load shedding protocols

• Unlike 2008, where Eskom implemented load shedding through-out the day and for a few days at a time, load shedding will now be used only under emergency conditions for limited periods.

• For Eskom customers only, four schedules have been developed based on the possibility of risk and to ensure that it is applied in a fair and equitable manner:

• An ‘All Day Schedule’ (24 hour) – Applicable during Summer and Emergencies (any time of the year)

• Three schedules for ‘Peak Stages’ during (5pm to 9pm) – Applicable during Winter.

• Eskom schedules cater for Eskom supply areas only

• Customers supplied by municipalities need to contact

their municipalities directly.

• Municipal load shedding is managed independently

34

National Code of Practice (NRS 048-9)Demand reduction under system critical constraints & emergencies

• Mandatory demand reduction – shedding vs. curtailment

Stage Type Reduction obtained by

interrupting supply -

load shedding

Reduction obtained by

instructing reduction -

curtailment (pre-agreed)

Stage 070-100 MW

Unscheduled

(pre-agreed)

Ad hoc Load offered by customers

under the immediate curtailment

option (min 25% for 2 hrs)

Stage 11600-2000 MW

Scheduled /

Notified

Shed 5% of national non-

curtailment load at peak

Curtail 10% of normal demand

within 2h of notification

Stage 22500-3200 MW

Scheduled /

Notified



Stage 35000-6300 MW

Scheduled /

Notified



Curtail 20% of normal demand

within 2hrs of notification

Stage 4 Unscheduled

(instructed)

Shed >20% of national non-


As instructed by the National

System Operator at the time.

sys

tem

em

erg

en

cy

35

Monday Tuesday Wednesday Thursday Friday Saturday

06:00 Block 9 Block 1 Block 9 Block 1 Block 9 Block 1








Stage 1 ALL DAY Schedule: Eskom customers only

The current schedule is designed

to be fair if load shedding takes

place during most of the day.

36

Where to locate the load shedding schedules: http://loadshedding.eskom.co.za

Option 3 – Internet

Add slides

37

Where to locate the load shedding schedules

38

Option 3 – Internet

Add slides

39

Key Message


System Status


Conclusion

Help us to communicate better

• While the load shedding schedules for Eskom customers were loaded, the system failed to perform optimally. Complaints were received around the accessibility of the site in particular

• Our customer contact centres were inundated and due to the overload were unable to help all customers

• We saw significant uptake on social media and we trended on twitter. We recorded a significant increase in social media shares of messaging across all platforms (130 million compared to daily trend of 1 million)

• The media houses reacted positively and we continue to have spokespeople across the country on various broadcasters to respond to media requests

• We welcome suggestions and feedback from the public on ways to improve the load shedding schedules. Please contact us on [email protected] or 0860037566

40

mailto:[email protected]

How to Live Lightly and Beat the Peak

• Saving electricity reduces pressure on the grid and cuts your electricity bill and South Africa’s carbon emissions

• The power system remains vulnerable all day during Summer

1. Use air-conditioning efficiently

- Set air-conditioning at 23 degrees

- Close windows and doors to optimize air-conditioning

- Switch off 30 minutes before leaving the office

2. Continue to switch off all geysers and pool pumps from 5pm to 9pm

3. As we approach winter, use alternatives to electrical heating

4. Switch off all non-essential lighting and appliances

5. Respond to the Power Alert and Power Bulletin radio messages by switching off all appliances that are not being used

41

In support of

Conclusion

• The system remains tight and is vulnerable to any changes going into Winter, and will remain so for the next few years until the build programme is completed

• With the projected demand and current trends in plant performance, extensive and expensive use of OCGTs is anticipated, resulting in limited operating reserves to deal with volatility in demand or generation performance.

• We call on all customers, particularly the municipalities and the commercial sectors, to manage and cut out all electricity wastage. The industrial and commercial sector can make significant contributions particularly in large office blocks and shopping centres.

• If this is done, it will ensure a stable power system and reduced costs

• We thank all our customers who continue to assist by reducing consumption.

Thank you

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