Final answer:
The calorific value of the fuel is calculated as 8.33 kWh/kg, for a steam power station has an overall efficiency of 20% and 0-6 kg of coal burnt per kWh of electrical energy generated.
Step-by-step explanation:
To calculate the calorific value of the fuel, we need to know the efficiency of the power station and the amount of coal burnt per kWh of electrical energy generated.
Given that the overall efficiency of the steam power station is 20% and 0.6 kg of coal is burnt per kWh of electrical energy generated, we can use the formula:
Calorific value of fuel = Electrical energy generated / Mass of coal burnt
Since the efficiency is defined as the ratio of useful energy output to total energy input, we can rewrite the formula as:
Calorific value of fuel = Electrical energy generated / (Efficiency * Mass of coal burnt)
Substituting the given values, we get:
Calorific value of fuel = 1 kWh / (0.2 * 0.6 kg)
= 8.33 kWh/kg