Cogeneration plants are designed for combined production of electric and heat power as steam and/or hot water. Electric power is directly related to the mechanical power of the gas turbine. As for heat power, it significantly varies in a wide range depending on the selected waste heat recovery configuration (steam or water type, combined steam and water type, or use of supplemental firing). The table below provides main parameters of typical CHP units with steam recovery boilers of 12-25 bars.
Implementation of additional low-pressure steam boilers of 3-6 bars pressure or hot water units for district heating are able to increase heat power by 25-35% over basic unfired heat units.
1 – Gas turbine engine
2 – Heat recovery boiler
3 – Generator
4 – Water tank
5 – Pump
6 – Heat consumer
Cogeneration units under service conditions