Heating System Efficiency (\( \xi_{hs} \)):

\[ \xi_{hs} = \left( \frac{Qsd}{Qaf} \right) \times 100 \]

Where:

• \( \xi_{hs} \) is the heating system efficiency, in percentage (%).
• \( Qsd \) is the heat supplied to the dryer, in kilojoules per hour (KJ/hr).
• \( Qaf \) is the heat available in the fuel, in kilojoules per hour (KJ/hr).