It takes 2.0 million tons of coal per year to feed a 1000-MWe steam-electric plant. Assuming that the plant has a 60% capacity factor, what is its efficiency? Coal has an energy content of 22 MBtu per ton. Assume two significant digits.

Respuesta :

Answer:

[tex]\eta = 40\%[/tex]

Explanation:

Total quantity of coal per year required is 2.0 million

capacity of electric plant = 1000 MWe

capacity factor 60%

energy content = 22 MBtu per ton

[tex]W_{max} = 1000 MWe[/tex]

[tex]60\% = \frac{w}{w_{max}}[/tex]

where w is actual power

we knwo that 1 Btu  = 0.000293 KWH

1MBtu = 293 KWH

Thermal  Efficiency is given as

[tex]\eta = \frac{w_{output}}{w_{input}}[/tex]

[tex]w_{output} = 1000\times 0.60 = 600 MW[/tex]

                [tex]= 600 \times 10^3 KW[/tex]

[tex]w_{input} = 2\times 10^6 ton/ year \times 22 MBtu/ ton[/tex]

               [tex] = \frac{2\times 10^6}{365\times 24} ton/ hr \times 22\times 293 KWH/ ton[/tex]

                [tex]= 1.5 \times 10^6 KW[/tex]

[tex]\eta = \frac{600\times 1000}{1.5\times 10^6} = 40\%[/tex]