Cogeneration heat/power ratio

The parameter influencing cogeneration is the ratio of power to process heat that can be supplied by a steam system (Kenney, 1984). This ratio is named as R ratio, which is expressed as... 

Coal gasification-based cogeneration has advantages over steam cycle cogeneration due to the much lower ratio of usable cogeneration heat to electric power and increased flexibility of coal gasification. 

The most appropriate cogeneration system for a site depends to a large extent on the site power-to-heat ratio, defined as15,16 ... 

Figure 23.44 The definition of cogeneration efficiency and site power-to-heat ratio. (From Varbanov P, Perry S, Makwana Y, Zhu XX and Smith, 2004, Trans IChemE, 82A 784, reproduced by permission of the Institution of Chemical Engineers.)...

Determine the rate of heat supply, net power output, process heat output, cycle efficiency, cogeneration ratio, and energy utility factor of the cycle. 

An important criterion in selecting a cogeneration system for a given application is the ratio of heat to power (H/P ratio) required. The demands of a process or an operating... 

George s position is much better, however. Using the same ratio of 0.9 Joule of steam endialpy per Joule of fuel heat, as in Monica s case, he will be getting about 0.9 Joule of electricity per extra - over Monica s - Joule of fuel heat. This is about twice what modem power plants get. But George read about this approach somewhere. It is called Cogeneration. 

In the typical case, the maximum pressure and temperature of the boiler are set by the manufacturer and, consequently, the ratio is determined by the turbine exhaust pressure, i.e. the process steam pressure. Typical values of this ratio are given in Table 5.3 and indicate that only low values of power to process heat ratio can be met with this type of cogeneration scheme. 

---