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 Homework Statement

Hi,
I have had a go at this question but have gone wrong somewhere, any ideas?
Thanks.
A coal fired steam plant takes in feed water at a temperature of 70°C and produces 15 tonnes of steam per hour at a pressure of 60 bar and temperature 400°C.
The fuel consumption rate is 1.5 tonnes per hour and the calorific value of the fuel is 40MJkgˉ¹.
Determine the power rating of the boiler and its thermal efficiency.
 Homework Equations

Q in = E x V
Q out = McΔT
Efficiency = Q out / Q in x 100
A coal fired steam plant takes in feed water at a temperature of 70°C and produces 15 tonnes of steam per hour at a pressure of 60 bar and temperature 400°C.
The fuel consumption rate is 1.5 tonnes per hour and the calorific value of the fuel is 40MJkgˉ¹.
Determine the power rating of the boiler and its thermal efficiency.
Power rating:
Q in = E x V
40,000,000Jkg^1 x 1500kg p/h / 3600 = 16,666,666,67 J/s
Q out = McΔT
15,000kg x 4.19 KJ/kg°c x (400°c – 70°c) / 3600 = 5,761.25 J/s
Thermal efficiency:
Efficiency = Q out / Q in x 100
5,761.25 J/s / 16,666,666.67 x 100 = 0.034%
The fuel consumption rate is 1.5 tonnes per hour and the calorific value of the fuel is 40MJkgˉ¹.
Determine the power rating of the boiler and its thermal efficiency.
Power rating:
Q in = E x V
40,000,000Jkg^1 x 1500kg p/h / 3600 = 16,666,666,67 J/s
Q out = McΔT
15,000kg x 4.19 KJ/kg°c x (400°c – 70°c) / 3600 = 5,761.25 J/s
Thermal efficiency:
Efficiency = Q out / Q in x 100
5,761.25 J/s / 16,666,666.67 x 100 = 0.034%