Catch a video of the presentation here: http://www.wartsilavirtualevents.com/ Presented in Power-Gen Asia in Bangkok on 3 October, 2012 by Saara Kujala, M.Sc.(Eng.), Manager, Development & Financial Services, Wärtsilä Singapore.

1. Improving power system efficiency with Fast Flexible
Power – Case Thailand
Saara Kujala
Manager, Development & Financial Services
Wartsila Singapore Pte Ltd
1 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

2. Flexibility in power systems
• Power systems need right types of capacities to
meet requirements for base load, intermediate load
and peak load Daily demand curve
• From investment point of view, new base load Demand %
100
plants are easy to justify due to the high committed Regulation
operating hours 80 Peak load
• Too much base load capacity pushes some base load
plants to operate as intermediate load, increasing
60 Intermediate load
their cost of generation and reducing system 40
flexibility
20 Base load
• Fast Flexible Power Plants (“FFP”) included as part
of Thailand’s power system can improve the 0
0 6 12 18 24
utilization of existing base load plants Cost of electricity is variable! Hour
• Considerable system level saving potential of
260 Million $ / year identified and quantified
2 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

3. Installed capacity in Thailand - 2012
• Almost 90% of the installed capacity is designed for *Plant Type Definitions
base load operation • Base load capacity
Plant GW Plant type*
• Slow start-up (>1hour)
EGAT Power Plants 15
CCGT 6.9 Base load • Slow ramp-up speed and slow response to
Fuel oil / Gas ST 2.2 Base load changing grid conditions
Fuel oil ST 0.3 Base load • Optimal efficiency at full load
Coal ST 2.2 Base load
• Flexible capacity
Hydro 3.4 Flexible
Diesel / Renewable 0.0 Peaking • Fast start-up time (<10 minutes)
IPP 12.2 • Fast ramp-up speed and fast response to grid
Bituminous coal 1.3 Base load conditions
CCGT 9.2 Base load
• High efficiency at all loads for flexible load
Fuel oil/ Gas ST 1.6 Base load
following
SPP 2.2
CCGT 1.4 Base load • Peaking capacity
Gas turbine (Simple cycle) 0.1 Peaking • Fast start-up time
Coal 0.4 Base load
• Fast ramp-up speed
Others 0.3 Base load
Hydro imports 2.2 Base/ Seasonal • Efficiency less important due to limited
Total 31.5 operating hours
Source: EGAT Annual report 2010
EPPO Energy Statistics July 2012
3 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

4. How will Thailand address the daily load following requirement?
Daily load curve 2010
• Distinctive load profile with three daily peaks
• Annual peak demand growth rate of 3.9%
6GW
• 25GW of coal, nuclear, co-generation and renewable
energy plants will enter into the system by 2030
providing base load electricity
• In addition, 25.4GW of new CCGTs in construction or
GW
Daily load curve 2012-2030 planning – These plants will be used for load following
50
45 14GW • Sufficient flexible power needs to be maintained in the
40 system to cope with normal demand variations and
2012
35 with variations caused by increasing share of wind and
2020
30
10GW
2030
solar generation
25
7GW
20
15 Sources: EGAT (Daily load curve of May 12, May 22 and May 23, 2010); PDP 2010 Rev 3
0:30 4:30 8:30 12:3016:3020:30
4 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

5. Typical daily load curve by technology and fuel – May 2010
Individual load curves (MW)
EGAT Hydro
2 000
GW System load curve (May 12, 2010)
25 0
• Domestic hydro power plants are an important
HFO ST
1 000 source of flexibility
0
20 2000
Gas ST
• First technology to respond to load changes –
0 primarily used for peak shaving
NG CCGT
15 6000
• Other generation capacity, most notably gas-fired
4000
2000
power plants (CCGT, Gas boilers, SPP) also respond
10 0 to load variations
3000 Lignite
• Varying operation profile negatively impacts the
0
5
2 000
IPP Hydro heat rate of CCGT plants
0 • System operation and regulation more challenging
0 8 000
with slow responding gas-fired technology
4:30
6:30
0:30
2:30
8:30
14:30
22:30
10:30
12:30
16:30
18:30
20:30
IPP CCGT
4 000
SPP IPP Bituminous
IPP CCGT IPP Hydro
Lignite Gas CCGT
Gas ST HFO 0
• Value of fast and flexible power generation is
Hydro 2 000 IPP Coal evident and demonstrated in the daily load curve
0 of domestic hydro power plants
Source: EGAT, May 12, 2010 2 000
SPP
0
5 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

6. Load following with gas fired power generation
25,0
May.12
700
600
20,0 500
400
15,0 300 CCGT-Based System:
200 700MW CCGT
10,0 100
0
5,0 0:30 4:30 8:30 12:3016:3020:30
Total generation cost ?
0,0
0:30 3:00 5:30 8:00 10:30 13:00 15:30 18:00 20:30 23:00
700
• A life-cycle cost analysis is conducted for single 700MW power 600
500
plant that operates according to the same load curve as the 400
power system in Thailand as a whole Flexible Power System:
300
• Efficiency and Levelized Electricity Cost (“LEC”) for a single 200 550MW CCGT +
plant are assumed to represent those for a larger system 100 150MW Fast Flexible Plant
0
0:30 4:30 8:30 12:3016:3020:30
6 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala
Total generation cost ?

7. Features of Fast Flexible Power with gas-fired combustion
engines
• High open cycle efficiency (>45% for the plant)
• Fast start and stop capability without EOH maintenance penalty
• Multiunit configuration
22xW18V50SG
Firm capacity
CCGT (2-2-1)
Firm capacity
7 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

8. Life cycle cost evaluation for flexible power plants -
Summary
CCGT –Based System Flexible Power System
700
FFP - Flexible generation
700
600
600
500
500
400 400
300 CCGT in load following 300 CCGT - Optimized base
200 200
100
load
100
0 0
0:30 4:30 8:30 12:3016:3020:30
0:30 4:30 8:30 12:3016:3020:30
Plant Type: CCGT –Based system Flexible Power System
Plant size: 700MW 550MW + 150MW = 700MW
CCGT efficiency 51.6% 53.2%
FFP efficiency - 45.3%
Total average efficiency (incl. fuel during
generation and start-ups), net, LHV 51.6% 52.5%
Levelized Electricity Cost (incl. annualized
2.32 Bht/kWh 2.22 Bht/kWh
capex, fuel, maintenance, start-up cost)
(77.2USD/MWh) (74.7USD/MWh)
8 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

9. Saving potential for the Thailand Power System (2010)
CCGT-Based System Flexible Power System Total saving with Flexible Power
System
Total gas fired capacity 2010 (GW) 18.3
Annual generation 2010 (TWh) 106.7
CCGT Installed capacity (GW) 18.3 14.4 FFP impacts the existing
FFP Installed capacity (GW) - 3.9 plants
Calculated efficiency (%) 51.6% 52.5% 0.9%-point
Calculated fuel use (Million MMBtu / Year) 706 693 13
Improved efficiency and lower fuel consumption in
Flexible Power System (Scenario II)
Generation cost (Million $ / Year) CCGT-Based System Flexible Power Total saving with Flexible
System Power System
Fuel charges (incl. start-up) 5 461 5 363 98
Fixed and variable O&M charges 647 615 32
Capacity charges 2 128 1 995 133
Total cost of electricity 8 326 7 973 263
263 Million USD saving in annual costs with
Flexible Power System (Scenario II)
9 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala

10. Conclusions
• Planning process for new power plants should be driven by
intended plant use (base load, flexible load, peaking).
• Planning process for new power capacity should recognize
the impacts on the load profiles and utilization of existing
plants.
• Fast Flexible Power plants can help to improve the
performance of the power system.
• Fast Flexible Power can be implemented gradually as part
of the Power Development Plan to match investment
timing with power demand growth.
10 © Wärtsilä 08 October 2012 Improving power system efficiency with Fast Flexible Power – Case Thailand / Saara Kujala