CHP System

Advantages

Disadvantages

Available sizes

Gas Turbine

· High reliability

· Low emissions

· High grade heat available

· No cooling required

· Require high pressure gas or inhouse gas compressor

· Poor efficiency at low loading

· Output falls as ambient temperature rises

Micro Turbine

· Small number of moving parts

· Compact size and light weight

· Low emissions

· No cooling required

· High cost

· Relatively low mechanical efficiency

· Limited to lower temperature cogeneration applications

30 KW - 250 KW

Internal Combustion Engine

· High power efficiency with part-load operational flexibility

· Fast start up

· Relatively low investment cost

· Can be used in island mode and have good load following capability

· Can be overhauled on site

· Operate on low pressure gas

· High maintenance costs

· Limited to lower temperature cogeneration applications

· Relatively high air emissions

· Must be cooled even if recovered heat is not used

· High level of low frequency noise

<5 MW in distributed generation

High speed (1200 rpm) ≤ 4 MW

Low speed (102 - 517 rpm) 4 - 75 MW

Steam turbine

· High overall efficiency

· Any type of fuel can be used

· Ability to meet more than one site heat grade requirement

· Long working life and high reliability

· Power to heat ratio can be varied

· Slow start up

· Low power to heat ratio

50 KW - 250 MW

Fuel cells

· Low emission and low noise

· High efficiency over load range

· Modular design

· High cost

· Low durability and power density

· Fuels requiring process

5 KW - 2 MW