Which of these fuels has the highest calorific value?

Options

A. Wood
B. LPG
C. Biogas
D. Coal

Answer

To determine which fuel has the highest calorific value among the given options (wood, LPG, biogas, and coal), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Calorific Value**:
- Calorific value is defined as the amount of heat produced when 1 kg of fuel is completely combusted in the presence of oxygen.

2. **Identify the Calorific Values of Each Fuel**:
- **Wood**: The calorific value of wood is between 17,000 and 22,000 kJ/kg.
- **LPG (Liquefied Petroleum Gas)**: The calorific value of LPG is approximately 55,000 kJ/kg.
- **Biogas**: The calorific value of biogas is between 35,000 and 40,000 kJ/kg.
- **Coal**: The calorific value of coal is between 25,000 and 33,000 kJ/kg.

3. **Compare the Calorific Values**:
- From the values identified:
- Wood: 17,000 to 22,000 kJ/kg
- LPG: 55,000 kJ/kg
- Biogas: 35,000 to 40,000 kJ/kg
- Coal: 25,000 to 33,000 kJ/kg
- We can see that LPG has the highest calorific value compared to the other fuels.

4. **Conclusion**:
- Therefore, among wood, LPG, biogas, and coal, the fuel with the highest calorific value is **LPG**.

### Final Answer:
The fuel with the highest calorific value is **LPG**.

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