Among the following fuels, which has highest calorific value?

Options

A. Blogas
B. Kerosene
C. Coal
D. Hydrogen gas

Explanation

To determine which fuel has the highest calorific value among the given options (biogas, kerosene, coal, and hydrogen gas), we will analyze the calorific values of each fuel.

### Step-by-Step Solution:

1. **Understand the Concept of Calorific Value**:
- Calorific value is defined as the amount of heat energy released when a substance is completely burned. It is usually expressed in kilojoules per kilogram (kJ/kg).

2. **List the Calorific Values of Each Fuel**:
- **Biogas**: The calorific value ranges from 35,000 to 40,000 kJ/kg.
- **Kerosene**: The calorific value is approximately 45,000 kJ/kg.
- **Coal**: The calorific value ranges from 25,000 to 33,000 kJ/kg.
- **Hydrogen Gas (H2)**: The calorific value is significantly higher, around 120,000 kJ/kg.

3. **Compare the Calorific Values**:
- Now, we compare the calorific values:
- Biogas: 35,000 - 40,000 kJ/kg
- Kerosene: 45,000 kJ/kg
- Coal: 25,000 - 33,000 kJ/kg
- Hydrogen Gas: 120,000 kJ/kg

4. **Identify the Highest Calorific Value**:
- From the comparison, it is clear that hydrogen gas has the highest calorific value at approximately 120,000 kJ/kg.

5. **Conclusion**:
- Therefore, the fuel with the highest calorific value among the options provided is **hydrogen gas (option D)**.