Power Plant Engineering

8.16 EFFICIENCY OF DIESEL POWER PLANT
The efficiency of a diesel engine plant is enhanced by use of Turbo-compounded diesel engine
and Heat Recovery Steam Generator (HRSG) and steam turbine generator.
A 24.8 mW Diesel Engine Generator Plant installed in Macau has two slow speed diesel engine
generator units (1985). The overall efficiency of nearly 50% has been demonstrated. The high efficiency
has been achieved by use of Turbine Generator, and Steam Turbine operated by exhaust gases of diesel
engine (Fig. 8.16).
This is claimed to be the first Diesel Power Plant in the world in which exhaust heat is recovered
and used for steam power generation. Thermal efficiency has been enhanced.
Fig. 8.17 shows the Heat Balance Diagram for the plant.
Stack
Fuel Gas
Desulphurisation
and dnox system
Steam Turbine
Generator
Cooling
Water
Condenser
Pump
Diesel
Engine
or Gas
Engine
Generator
Exhaust
Gas
Air
Fuel
Heat Recovery
Steam Generator
Fig. 8.16. Combined Cycle: Diesel Engine, HRSG and Steam Turbine.

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POWER PLANT ENGINEERING
Table 8.1.  Technical Data about Diesel Engine-Steam Turbine Cogeneration Power Plant
No. of diesel engine generator units
2 × 24.4 mW
Rating of each unit at speed
24.8 mW at 100 rpm
No. of cylinders per engine
9
Bore/stroke
800
2300
mm
Diesel engine mitsui/MAN B and W
2 Stroke Low Speed
Generators 2 Nos. 11 kV, 50 Hz, 100 RPM
29.8 kVA each
Steam Turbine
0.67 mW
Gas Turbo Generator System
0.5 mW
Location
Macau, Canton, China
Heat Radiation Loss
248 kW (0.5%)
Charge Air Cooler
6547 kW (13.2%)
Fresh Water Cooler
3472 kW (7.0%)
Lube Oil Cooler
2034 kW (4.1%)
Fuel Oil 49598
kW (100%)
Diesel Engine 9K80 MC-S
Exhaust
Gas
Turbo Compound System
(TCS)
Fuel Oil Preheating
595 kW (1.2%)
Exhaust Gas to
Stack
11160 kW (22.5%)
Generator Loss
744 kW (1.5%)
Generator
Turbogenerator
Boiler
TCS
471 kW
Turbogenerator
670 kW 50%
24.8 MW
Measured at site
Output
23.64 MW
Fig. 8.17. Heat Balance of a Diesel Engine Power Plant.

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DIESEL POWER PLANT
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