Question

Fuel selection for electricity generation

1. Uncontrolled emission factors and heating value data for bituminous coal, residual fuel oil and natural gas burned in utility boilers are given in Table 1. Consider a thermal electric power plant that generates an average of 400 MW of electricity with an overall efficiency of 35%. Determine for each fuel the annual uncontrolled mass of each of the pollutants (in units of metric tonnes per year) that would be emitted from such a power plant. Please interpret your results. Is our analysis complete? What else needs to be taken into consideration to assess which fuel is the most clean? (20 points)

The following might be useful:

• Energy (MJ) = Power (MW) * Time (s)

• The overall efficiency of the power plant is: Effisicenty= (electricity produced)/[(heating value)*quantity of fuel)]

• 1 gal = 3.785x10-3 m3

• Table 1: Uncontrolled emission factors and heating value data

	Bituminous coal	Residual fuel oil	Natural gas
	(pulverized, 1.8% S)	(no. 6, 2% S)
Heating value:	33.25 MJ/kgfuel	41809.8 MJ/m3	41.9 MJ m-3
Emission factors:
CO2	2.38 kg/kgfuel	11.6 kg/galfuel	2.2 kg/m3
Particles	31 kg/Mgfuel	2.9 kg/m3	16 x 10-6 kg/m3
SO2	35 kg/Mgfuel	38 kg/m3	9.6 x 10-6 kg/m3
NO	6.9 kg/Mgfuel	8 kg/m3	8800 x 10-6 kg/m3

Answer 1