Question

A steam power plant with a power output of 150 mw consumes coal at a rate of 60 tonnes per hour. If the heating value of coal is 30,000 kj/kg, determine the overall efficiency (in %) of the plant.

Answer 1

The efficiency increases with increasing steam pressure nonlinearly up to a level. ... Explanation: Thermal efficiency of steam power plant is the ratio of the heat equivalent of mechanical energy transmitted to the turbine shaft and the heat of the combustion. Thermal efficiency is generally quite low about 30%

Answer 2

Answer:

30%

Explanation:

thermal efficiency: $e_{th}$=$\frac{W_{out} }{Q_{in} }$*100

$Q_{in}$=$m_{coal}$*$HU_{coal}$

$m_{coal}$=60 tons/h=50/3 kg/s

$HU_{coal}$=30000kj/kg=30MJ/kg

$Q_{in}$=500 MW

$e_{th}$=$\frac{150}{500}$*100=30%