The formula to calculate the power density in a biomass furnace is:

\[ PD = \frac{FCR}{A_g} \]

Where:

• \(PD\) is the power density in kilograms per hour per square meter (kg/hr-m²).
• \(FCR\) is the fuel consumption rate in kilograms per hour (kg/hr).
• \(A_g\) is the grate area in square meters (m²).