part 1: overview of cogeneration and its status in asia - Fire

110 Part3: Summary of country studies – Bangladesh and Viet Nam
Excess(+)/Deficit(-) Power, MWh/year -1,480 5,485
Fuel Consumption, TJ/year 116 187
Gas Turbine
Figure 2.4 shows a typical gas turbine cogeneration unit. Gas turbine cogeneration unit has
the following advantages over other internal combustion engine drives: small size and high
power to heat ratio, ability to burn a variety of fuels, clean dry exhaust and hence ability to
meet stringent pollution standards, high reliability and easy maintenance. Table 2.6 presents
the typical heat disposition of gas turbines.
Electricity
Generator
G
Air
Gas Turbine
Flue
Gas
Fuel
Exhaust Gas
HRSG
Figure 2.4 Gas turbine with heat recovery steam generator
Table 2.6 Gas turbine heat balance
Water
Steam
Small Units Medium Size Units
Electricity 21 per cent 29 per cent
Exhaust Heat (Theoretically Recoverable) 53 per cent 46 per cent
Exhaust Heat (Not Recoverable) 21 per cent 20 per cent
Generator, Oil Cooler and Radiation Losses 5 per cent 5 per cent
Total (Fuel Input) 100 per cent 100 per cent
Following the same way as that for reciprocating engine cogeneration unit, the power to heat
ratio, power generation and heat generation, fuel consumption, etc., can be calculated. The
results are shown in Table 2.7.