Tables

1. Statistical overview  

                                
  2011     2010     2009     2008     2007     2006     2005  
(15 -  
months) 		   2004     2003     2002     2001  
                                           
Sales                                            
Total sold (GWh)1, 2   224 446     218 591     214 850     224 366     218 120     207 921     256 453     206 799     196 980     187 957     181 511  
Growth/(reduction) in GWh sales (%)  2.7     1.7     (4.2)    2.9     4.9     (18.9)3     30.5     5.0     4.8     3.5     1.8  
Electricity output                                            
Total produced by Eskom stations (GWh (net))  237 430     232 812     228 944     239 109     232 445     221 988     273 404     220 152     210 218     197 737     189 590  
Coal-fired stations (GWh (net))  220 219     215 940     211 941     222 908     215 211     206 606     251 914     202 171     194 046     181 651     175 223  
Hydro-electric stations (GWh (net))  1 960     1 274     1 082     751     2 443     1 141     903     720     777     2 357     2 061  
Pumped storage stations (GWh (net))  2 953     2 742     2 772     2 979     2 947     2 867     3 675     2 981     2 732     1 738     1 587  
Gas turbine stations (GWh (net))  197     49     143     1 153     62     78     –     –     –     –     –  
Wind energy (GWh (net))  2     1     2     1     2     3     –     –     –     –     –  
Nuclear power station (GWh (net))  12 099     12 806     13 004     11 317     11 780     11 293     16 912     14 280     12 663     11 991     10 719  
Total purchased for Eskom system (GWh)  15 446     13 754     12 189     11 510     11 483     10 310     12 197     9 818     8 194     9 496     9 200  
Total electricity for Eskom system (Eskom stations and purchased) (GWh)4   252 876     246 566     241 133     250 619     243 928     232 298     285 601     229 970     218 412     207 233     198 790  
Total consumed by Eskom (GWh)5   3 962     3 695     3 816     4 136     3 937     3 814     5 043     4 040     3 664     2 354     2 177  
Total available for distribution (GWh)2   248 914     242 871     237 317     246 483     239 991      228 484     280 558     225 930     214 748     204 879     196 613  
Plant performance indicators                                            
Total power station nominal capacity (MW)  44 145     44 175     44 193     43 037     42 618     42 011     42 011     42 011     42 011     42 011     42 011  
Total power station net maximum capacity (MW)   41 194     40 870     40 506     38 747     37 761     36 398     36 208     36 208     36 208     36 208     36 208  
Peak demand on integrated Eskom system (MW)  36 664     35 850     35 959     36 513     34 807     33 461     34 195     34 195     31 928     31 621     30 599  
Peak demand on integrated Eskom system, including load reductions(MW)  36 970     35 912     36 227     37 158     35 441     33 461     34 195     34 195     31 928     31 621     30 599  
Reserve margin (including imports) (%)  14.9     16.4     10.6     5.6     7.8     12.7     –     –     –     –     –  
Average energy availability – EAF (UCF) (%)6   84.6  
(85.9) 		   85.2  
(85.9) 		   85.3  
(86.1) 		   84.8  
(86.2) 		   87.5  
(88.6) 		   87.4  
(88.7) 		   89.5  
(89.9)7  		   89.5  
(90.0) 		   87.5  
(88.7) 		   89.3  
(91.7) 		   92.0 (92.5) 
Generation load factor (%)8   66.4     66.2     67.0     72.3     72.4     69.7     69.0     69.2     66.3     62.3     59.8  
Integrated Eskom system load factor (EUF) (%)  78.5     77.7     78.6     85.2     82.7     79.8     78.0     77.4     76.8     74.0     73.4  
Environmental indicators                                            
Specific water consumption (L/kWh sent out)9   1.35RA     1.34RA     1.35RA     1.32     1.35     1.32     1.277     1.26     1.29     1.27     1.26  
Significant legal contraventions reported (number)10   4     0     12     6     0     1     37     2     2     3     2  
Customer satisfaction (Enhanced PreCare/MaxiCare) (ratio)11   98.20     99.65     99.84     97.21     100.80     101.06     93.10     8.31     8.47     8.57     8.43  
Net raw water consumption (ML)  327 252     316 202     323 190     322 666     313 064     291 516     347 135     277 557     271 940     251 611     239 233  
Liquid fuels (diesel and kerosene) (ML)  63.6RA     16.1RA     28.9LA     345.9     11.3     –     –     –     –     –     –  
Coal burnt (Mt)  124.7     122.7     121.2     125.3     119.1     112.1     136.4     109.6     104.4     96.5     94.1  
Average calorific value (MJ/kg)  19.45     19.22     19.10     18.51     19.06     19.58     19.36     19.42     19.41     19.54     19.42  
Average ash content (%)  29.03     29.56     29.70     29.09     29.70     29.10     29.60     29.60     28.90     28.40     28.80  
Average sulphur content (%)  0.78     0.81     0.83     0.87     0.86     0.88     0.87     0.87     0.92     0.92     0.93  
Overall thermal efficiency (%)  32.6     33.1     33.4     33.4     33.9     33.8     34.0     34.0     34.2     34.1     34.1  
Line losses (%)  8.3     8.5     7.9     8.0     8.4     8.2     8.27     7.8     8.3     8.2     7.2  
Nitrous oxide (N2O) (t)12   2 906     2 825     2 801     2 872     2 730     3 134     3 552     2 924     2 580     2 246     2 154  
Carbon dioxide (CO2) (Mt)12   230.3RA     224.7RA     221.7RA     223.6     208.9     203.7     247.0     197.7     190.1     175.2     169.3  
Sulphur dioxide (SO2) (kt)12   1 810RA     1 856RA     1 874RA     1 950     1 876     1 763     2 236     1 779     1 728     1 494     1 500  
Nitrogen oxide (NOx) as NO2 (kt)12   977RA     959RA     957LA     984     930     877     994     797     760     702     684  
Relative particulate emissions (kg/MWh sent out)13   0.33RA     0.39RA     0.27RA     0.21     0.20     0.21     0.267     0.27     0.28     0.29     0.31  
Particulate emissions (kt)13   75.84RA     88.27RA     55.64RA     50.84     46.08     45.76     72.83     59.17     58.65     57.53     59.64  
Ash produced (Mt)  36.22RA     36.01RA     36.66LA     36.04     34.16     33.40     40.80     33.10     29.80     26.20     26.50  
Ash sold (Mt)  2.0RA     2.0RA     2.1     2.4     2.2     1.8     2.0     1.6     1.2     1.3     1.2  
Asbestos disposed of (tons)  611.5RA     321.4RA     3 590.8LA     321.0     6 060.0     –     –     –     –     –     –  
PCB thermally destructed (tons)  422.9RA     19.1RA     505.6LA     17.0     10.00     –     –     –     –     –     –  
Calculated public effective radiation dose (mSv)14   0.0043     0.0040     0.0045     0.0047     0.0034     0.0049     0.00797     0.0087     0.0123     0.0060     0.0192  
Low-level radioactive waste generated (m3)15   165.3RA     137.8     140.8     180.3     94.5     90.2     80.3     81.4     100.5     111.9     82.6  
Intermediate-level radioactive waste generated (m3)15   39.4RA     47.1     23.9     16.5     49.8     52.7     47.2     36.8     30.1     45.8     22.1  
Low-level radioactive waste disposed of (m3)  81.0RA     216.0RA     189.0     270.0     135.0     91.0     –     –     –     –     –  
Intermediate-level radioactive waste disposed of (m3)  0.0RA     266.0RA     473.6     418.0     436.0     52.0     –     –     –     –     –  
Low-level nuclear waste – fuel racks (m3)16 (cumulative figure)  0 (697)    0 (697)    0 (697)    0 (697)    0 (697)    0 (697)    0 (697)    697     –     –     –  
Spent nuclear fuel, number of elements discharged17 (cumulative figure)  112  
(1 897) 		   56  
(1 785) 		   56  
(1 729) 		   112  
(1 673) 		   56  
(1 561) 		   52  
(1 505) 		   104  
(1 453) 		   56  
(1 405) 		   104  
(1 349) 		   48  
(1 245)  		   104  
(1 197) 
1. Sales prior to 2005 include internal sales.
2. Difference between electricity available for distribution and electricity sold is due to transmission and other losses.
3. Actual sales growth was 0.8% when compared to the 12 months 1 April 2004 to 31 March 2005.
4. Includes Eskom electricity produced and delivered to neighbouring countries.
5. Used by Eskom for pumped storage facilities and synchronous condenser mode of operation.
6. Capacity hours available, times 100, divided by total capacity hours in a year.
7. Represents the 12-month moving average for 1 April 2004 to 31 March 2005.
8. kWh produced, times 100, divided by average net maximum capacity times hours in a year.
9. Volume of water consumed per unit of generated power sent out from coal fired power stations, excluding Komati and Grootvlei power stations.
10. 2001 to 2002 reported in terms of the revised definition of the operational health dashboard. From 2008, repeat legal contraventions are included in the criteria.
11. Reflects the environmental element of Enhanced MaxiCare. The Enhanced MaxiCare replaced the PreCare/MaxiCare from January 2005.
12. Calculated figures are based on coal characteristics and the power station design parameters. SO2 , NOx and CO2 emissions are based on coal analysis and tonnages of coal burnt in 2010/11. From 2009 includes Camden, Grootvlei and the gas turbine power stations as well as oil consumed during power station start-ups. From 2010, total CO2 includes the additional contribution from the Underground Coal Gasification pilot project (flaring) and Komati power station.
13. The overall particulate performance figure is based on individual power station performance. For certain power stations, emission figures are based on best estimates.
14. The limit set by the National Nuclear Regulator is ≤ 0,25mSv.
15. These are the net volumes produced in a 12-month moving window.
16. Waste as a result of re-racking of spent fuel pools at Koeberg power station.
17. The gross mass of a nuclear fuel element is approximately 665kg, with UO2 mass typically between 462 and 464kg.
RA– Reasonable Assurance provided by the independent assurance provider (Refer here).
LA– Limited assurance provided by the independent assurance provider (Refer here).

2. Power station commercial capacities at 31 March 2011  
Name of station Location Number and  
current capacity of  
 Total  
nominal  
 Total net  
maximum  
 Generators in  
reserve storage  		 Other  
generation  
Total  
rating  
    generator sets   capacity   capacity     Nominal  
rating  
    MW   MW   MW1   Number   MW   MW2  
Coal-fired stations (13)      37 745   34 952   7   825   –  
Arnot3   Middelburg, Mpumalanga   1 x 370; 1 x 390; 2 x 396; 2 x 400;   2 352   2 232   –   –   –  
Camden4, 9   Ermelo   2 x 200; 1 x 195; 2 x 190; 1 x 170; 1 x 180; 1 x 185   1 510   1,430      –   –  
Duvha3   Witbank   6 x 600   3 600   3 450   –   –   –  
Grootvlei4, 10, 11   Balfour   6 x 200   1 200   950   1   200   –  
Hendrina3   Mpumalanga   8 x 200; 1 x 195; 1 x 170   1 965   1 865   –   –   –  
Kendal3, 5   Witbank   6 x 686   4 116   3 840   –   –   –  
Komati4, 9,10    Middelburg, Mpumalanga   5 x 100; 2 x 125; 2 x 95   940   284   6   625   –  
Kriel3   Bethal   6 x 500   3 000   2 850   –   –   –  
Lethabo3   Viljoensdrift   6 x 618   3 708   3 558   –   –   –  
Majuba3, 5   Volksrust   3 x 657; 3 x 713   4 110   3 843   –   –   –  
Matimba3, 5   Lephalale   6 x 665   3 990   3 690   –   –   –  
Matla3   Bethal   6 x 600   3 600   3 450   –   –   –  
Tutuka3   Standerton   6 x 609   3 654   3 510   –   –   –  
Gas/liquid fuel turbine stations6 (4)      2 426   2 409   –   –   –  
Acacia6   Cape Town   3 x 57   171   171   –   –   –  
Ankerlig6   Atlantis   4 x 149,2; 5 x 148,3   1 338   1 327   –   –   –  
Gourikwa6   Mossel Bay   5 x 149,2   746   740   –   –   –  
Port Rex6   East London   3 x 57   171   171   –   –   –  
Hydro-electric stations (6)      661   600   –   –   61  
Colley Wobbles2   Mbashe River   3 x 14   42   –   –   –   42  
First Falls2   Mthatha River   2 x 3   6   –   –   –   6  
Gariep7   Norvalspont   4 x 90   360   360   –   –   –  
Ncora2   Ncora River   2 x 0.4; 1 x 1.3   2   –   –   –   2  
Second Falls2   Mthatha River   2 x 5.5   11   –   –   –   11  
Vanderkloof 7   Petrusville   2 x 120   240   240   –   –   –  
      1 400   1 400   –   –     
Pumped storage schemes8 (2)               
Drakensberg8   Bergville   4 x 250   1 000   1 000   –   –   –  
Palmiet8   Grabouw   2 x 200   400   400   –   –   –  
Wind Energy (1)               
Klipheuwel2   Klipheuwel   1 x 1.75; 1 x 0.66; 1 x 0.75   3   3   –   –   –  
Nuclear power station (1)               
Koeberg3,12   Cape Town   1 x 940; 1 x 970;   1 910   1 830   –   –   –  
Total power station capacities (27)      44 145   41 194   7   825   61  
   
1. Difference between nominal and net maximum capacity reflects auxiliary power consumption.
2. Operational but not included for capacity management purposes.
3. Base-load station.
4. Return-to-service station.
5. Dry-cooled unit specifications are based on design back-pressure and ambient air temperature.
6. Stations used for peaking or emergency supplies.
7. Use restricted to peaking, emergencies and availability of water in Gariep and Vanderkloof dams.
8. Pumped storage facilities are net users of electricity. Water is pumped during off-peak periods so that electricity can be generated during peak periods.
9. Due to technical constraints, some units at Camden and Komati have been de-rated.
10. Units commissioned for the first time at these RTS stations were running their 12-month performance confirmation period during the period under review.
11. Grootvlei unit 4’s normal 12-month performance confirmation period was extended to 21 months due to technical constraints.
12. Due to technical constraints, Koeberg units were de-rated to a total nominal capacity of 1 880MW (1 800MW net maximum). During the period under review the output of unit 1 was increased by 30MW after a turbine retrofit, increasing the total nominal capacity.


3. Environmental implications of using or saving one kilowatt-hour of electricity1

  Factor (total  
energy  
generated)2		     If electricity consumption is measured in:
    kWh MWh GWh TWh
Coal use 0.53   kilogram ton thousand tons (kt) million tons (Mt)
Water use3 1.40   litre kilolitre megalitre (ML) thousand megalitres (GL)
Ash produced 155   gram kilogram ton (t) thousand tons (kt)
Particulate emissions 0.33   gram kilogram ton (t) thousand tons (kt)
CO2 emissions4 0.99   kilogram ton thousand tons (kt) million tons (Mt)
SO2 emissions4 7.75   gram kilogram ton (t) thousand tons (kt)
NOx emissions4 4.18   gram kilogram ton (t) thousand tons (kt)

Use of table: Multiply electricity consumption or saving by the relevant factor to determine the environmental implication.

Example 1: Example 2:
Used 90kWh of electricity Used 90GWh of electricity
Water consumption: 90 x 1.40 = 126 CO2 emissions 90 x 0.99 = 89.10
Therefore 126 litres of water used Therefore 89.1 thousand tons emitted

   
1. Factor figures are calculated based on total energy generated by Eskom (but excluding electricity used for pumping water for the pumped-storage schemes). Further information can be obtained through the Eskom environmental helpline. Contact details appear on the inside back cover.
2. Figures represent the 12-month period from 1 April 2010 to 31 March 2011.
3. Volume of water used at all Eskom power stations.
4. Calculated figures are based on coal characteristics and the power station design parameters. SO2 , NOx and CO2 emissions are based on coal analysis and tonnages of coal burnt in 2010/11. Emissions include Camden, Grootvlei, Komati, the gas turbine power stations, oil consumed during power station start-ups, as well as the additional contribution from the underground coal gasification pilot project (flaring).

4. Transmission and distribution equipment in service at 31 March 2011  
    2011     2010     2009  
Power lines             
Transmission power lines (km)1     28 790     28 482     28 243  
765kV     1 153     1 153     1 153  
533kV DC (monopolar)    1 035     1 035     1 035  
400kV2     16 913     16 582     16 343  
275kV     7 476     7 390     7 390  
220kV     1 217     1 333     1 333  
132kV     996     989     989  
Distribution power lines (km)    46 712     46 018     45 302  
165 – 132kV     25 075     24 514     23 856  
88 – 33kV     21 637     21 504     21 446  
Reticulation power lines (km)             
22kV and lower     308 899     305 151     297 783  
Underground cables (km)    11 018     10 687     10 379  
165 – 132kV     230     197     179  
22kV and lower     10 788     10 490     10 200  
Total all power lines (km)     395 419     390 338     381 707  
Total transformer capacity (MVA)    232 058     223 398     220 512  
Transmission (MVA)3     130 005     123 990     124 140  
Distribution and reticulation (MVA)    102 053     99 408     96 372  
Total transformers, number     351 297     344 369     333 949  
Transmission, number     405     399     398  
Distribution and reticulation (number)    350 892     343 970     333 551  
1. Transmission power line lengths as per Geographic Information System (GIS) distances.
2. The Majuba-Umfolozi No1 765kV line, even though constructed at 765kV, is currently still being operated at 400kV and thus, for now, is counted under the 400kV total.
3. Base of definition: transformers rated ≥30MVA and primary voltage ≥132kV.
 

5. Sale of electricity and revenue per category of customer  
  Customers  
Category   2011  
Number  		   2010  
Number  		   2009  
Number  
Local   4 653 740    4 463 291     4 360 997  
Redistributors   784     773     769  
Residential1, 2   4 514 998     4 325 550     4 223 708  
Commercial   49 090     47 984     47 603  
Industrial   2 857     2 925     2 935  
Mining   1 110     1 134     1 144  
Agricultural   84 393     84 415     84 329  
Traction   508     510     509  
International   10     10     10  
Utilities   7     7     7  
End users across the border   3     3     3  
  4 653 750    4 463 301    4 361 007  
Category   Sold  
2011  
GWh  		   2010  
GWh  		   2009  
GWh  
Local   211 150     205 364     202 202  
Redistributors   91 564     90 712     88 345  
Residential1   10 539     10 350     10 392  
Commercial   9 020     8 889     8 642  
Industrial   59 611     55 816     54 815  
Mining   32 630     31 733     32 177  
Agricultural   4 919     5 010     4 913  
Traction   2 867     2 854     2 918  
International   13 296     13 227     12 648  
Utilities   3 974     4 109     3 525  
End users across the border   9 322     9 118     9 123  
  224 446    218 591    214 850  
         

Sales to countries in southern Africa (GWh)  

          
  13 296    13 227    12 648
Botswana   2 377     2 684     1 959  
Mozambique   8 523     8 326     8 243  
Namibia   1 559     1 459     1 573  
Zimbabwe   0     6     0  
Lesotho   247     121     107  
Swaziland   564     597     756  
Zambia   23     33     10  
Short-term energy market3   3     1     –  
           
1. Prepayments and public lighting are included under residential.
2. The total number of disconnections within the reporting period is the amount of 79 771 and the total number of reconnections is 46 442.
3. The short-term energy market consists of all the utilities in the southern African countries that form part of the Southern African Power Pool. Energy is traded on a daily, weekly and monthly basis as there is no long-term bilateral contract.

Category   Revenue  
2011  
Rm  		   2010  
Rm  		   2009  
Rm  
Local   86 358     66 970     50 766  
Redistributors   36 191     27 973     20 362  
Residential1   7 003     6 622     5 493  
Commercial   4 747     3 642     2 704  
Industrial   20 469     15 089     11 762  
Mining   12 979     9 599     7 360  
Agricultural   3 577     2 954     2 225  
Traction   1 392     1 091     860  
International   4 127     2 972     2 334  
Utilities   2 019     1 561     978  
End users across the border   2 108     1 411     1 356  
Gross electricity revenue   90 485     69 942     53 100  
Less: revenue capitalised2   (110)    (108)    (104) 
Electricity revenue per note 29   90 375     69 834     52 996  
Levies included in revenue:            
The EDI restructuring levy3   n/a     n/a     594  
The environmental levy4   4 335     3 263     n/a  
   
1. Prepayments and public lighting are included under residential.
2. Revenue from the sale of production while testing Generation plant not yet commissioned, capitalised to plant.
3. The EDI restructuring levy was paid over to EDI Holdings (Pty) Limited in 2009 in terms of MYPD 1.
4. The environmental levy is a 2c/kWh tax, effective from 1 July 2009, payable for electricity produced from non-renewable sources (coal, nuclear and petroleum). The levy is raised on the total electricity production volumes and is recovered through sales.