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THE FUTURE OF COAL:
EXISTING POWER STATIONS
CONSIDERATIONS FOR NEW STATIONS
Brett Cohen
sti!s Power Sector Workshop
5 March 2013
EXISTING POWER STATION FLEET
Power station Net maximum capacity (MW)
Nominal capacity (MW)
Arnot 2,232 2,352
Camden 1,450 1,530
Duvha 3,450 3,600
Grootvlei 380 (1,090) 400 (1,150)
Hendrina 1,865 1,965
Kendal 3,840 4,116
Komati 170 (878) 182 (940)
Kriel 2,850 3,000
Lethabo 3,558 3,708
Majuba 3,843 4,110
Matimba 3,690 3,990
Matla 3,450 3,600
Tutuka 3,510 3,654
Medupi 0 (4,332) 0 (4,618)
Kusile 0 (4,338) 0 (4,680)
POWER STATION COAL REQUIREMENTS Power station CV Range
Arnot
22 – 24 MJ/kg Camden
Tutuka (on the border)
Kriel
20 – 22 MJ/kg
Duvha
Grootvlei
Hendrina
Komati
Majuba
Matla
Kendal
18 – 20 MJ/kg
Matimba
Medupi
Kusile
Lethabo 16 – 18 MJ/kg
LATE DECOMMISSIONING – 23,283 MW BY 2040
-6000
-5000
-4000
-3000
-2000
-1000
0
1000
2000
3000
MW
Arnot Camden Duvha Grootvlei Hendrina Kendal Komati Kriel
Lethabo Majuba Matimba Matla Tutuka Medupi Kusile
6,868 MW: Camden
Komati
Grootvlei
Matla
3,450 MW: Duvha
12,965 MW: Arnot
Hendrina
Kriel
Lethabo
Matimba Tutuka
MID-DECOMMISSIONING – 28,023 MW BY 2040
-6000
-5000
-4000
-3000
-2000
-1000
0
1000
2000
3000
MW
Arnot Camden Duvha Grootvlei Hendrina Kendal Komati Kriel
Lethabo Majuba Matimba Matla Tutuka Medupi Kusile
6,868 MW: Camden
Komati
Grootvlei
Matla
3,450 MW: Duvha
4,097 MW: Arnot
Hendrina
13,068 MW: Kriel
Lethabo
Matimba
Tutuka
EARLY DECOMMISSIONING – 32,028 MW BY 2040
-6000
-5000
-4000
-3000
-2000
-1000
0
1000
2000
3000
MW
Arnot Camden Duvha Grootvlei Hendrina Kendal Komati Kriel
Lethabo Majuba Matimba Matla Tutuka Medupi Kusile
6,868 MW: Camden
Komati
Grootvlei
Matla
3,450 MW: Duvha
4,097 MW: Arnot
Hendrina
17,448 MW: Kendal
Kriel
Lethabo
Matimba
Tutuka
SUMMARY: LIFE OF COAL FIRED POWER
STATIONS
! " Decommissioned under IRP: Camden, Komati, Grootvlei, Matla and Duvha
! " Partly or fully decommissioned between 2030 and 2040 :
Hendrina, Arnot, Tutuka, Lethabo, Kriel, Matimba and Kendal
! " Still fully operational in 2040: Majuba, Medupi and Kusile
COAL FOR EXISTING POWER STATIONS
! " Power stations historically supplied via long-
term contracts
! " Mines nearing end of lives – new coal needs to be sourced, to extend power station lives
! " Eskom estimates:
•" 2,000 Mt total coal required from new
mines now to 2050
•" 300 to 800 Mt threatened by exports:
›" Supply in 22-24 MJ/kg band (Arnot,
Camden and Tutuka) competes with exports (RB3 grade)
•" 80 Mt/a required from new mines
COAL FOR EXISTING POWER STATIONS
! " Sufficient coal in the Central Basin to 2040
•" Some big blocks earmarked for export – could swing availability for Eskom in Central Basin
! " Alternative to build rail line to obtain coal from Waterberg
•" Allow for continued exports
! " Potential challenges post 2040 for remaining power stations
! " Mine investment remains a big problem
•" Lack of investment appetite from large mining houses
! " Other options for coal supply:
•" Discards
•" Re-mining pillars
OPTIONS FOR NEW COAL POWER STATIONS?
! " Waterberg:
•" New PF stations
•" FBC
! " Challenges:
•" Low grade/yields
›" Costly to wash
›" Difficult to mine
•" Dual product mines suggested to be more profitable
›" Requires rail infrastructure for exports
•" Water availability
OPTIONS FOR NEW COAL POWER STATIONS?
! Fluidised bed combustion of discards/fines in Central Basin
•" Large volumes of limestone sorbent
•" Transport and CO2 impacts
! " One new 6-pack in Central Basin?
! " Location at the coast:
•" Closer to CCS injection sites
•" Rail coal instead of transporting water and CO2
TECHNOLOGY CHOICE ! " Ultra-supercritical plants
•" Significant efficiency gains (~47%)
•" Reduced CO2/kWh
! " UCG
•" Could unlock some seams not suitable for mining
•" Not before mid-2020s
! " IGCC
•" Efficiencies > 50%
Chapter 5 - Power and renewables outlook 181
5
Figure 5.4 ! Incremental global coal-fired electricity generation relativeto 2009 by region in the New Policies Scenario
-1 000
0
1 000
2 000
3 000
4 000
5 000
2015 2020 2025 2030 2035
TWh Other non-OECD
India
China
OECD
In the New Policies Scenario, the mix of coal-fired generation technologies changes overthe Outlook period as older plants are retired and more efficient new plants are built,including ultra-supercritical designs and integrated gasification combined-cycle (IGCC) plants(Figure 5.5).1 Increases in the price of coal, reductions in the capital costs of advanced coaltechnologies and the introduction of carbon prices all contribute to the shift towards higher-efficiency coal plants. As a result, the average global thermal efficiency of coal plants increasesby four percentage points, from38% in 2009 to 42% in 2035. Thesemore efficient technologiesentail higher capital costs than the subcritical and supercritical plant designs that make upmost of the current fleet of coal-fired plants, but they use less fuel and, therefore, emit lessCO2 and other emissions for each unit of electricity they generate. Lower fuel use due to higherefficiency plants also helps tomoderate import dependence for importing countries.
Figure 5.5 ! World coal-fired electricity generation by plant type in the NewPolicies Scenario
0
2 000
4 000
6 000
8 000
10 000
12 000
2009 2015 20252020 2030 2035
TWh Coal-fired CHP
plants
Coal plants fi!edwith CCS
Advanced coalplants*
Supercri"cal plants
Subcri"cal plants
*Advanced coal plants include ultra-supercritical and IGCC plants.
1. See Chapter 10 for a detailed discussion of coal-!red genera!on technologies.
© O
EC
D/I
EA
, 2
01
1Source: WEO 2011
COAL AND CCS: CHALLENGES
! " Availability of capture sites
! " Cost implications
! " Legal/regulatory/risk
! " High water penalties
! " Possible retrofit only on Medupi and Kusile
! " 85% carbon is sequestered
! " Net thermal efficiency penalty ~ 9.6%
•" Results in significant additional coal requirements and infrastructure build
SUMMARY
! " Existing power stations run to 2030, thereafter rapid
decommissioning
•" Coal supply remains a challenge particularly 22-24 MJ/kg
•" Need investment in new mines if existing power stations
continue to operate
! " New coal fired power station options:
•" Waterberg, Central Basin
•" Technology choices – post 2030
›" Potential for greater efficiency and reduced CO2
! " CCS comes with major challenges
THANK YOU
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