From the engineering reference...

$$Q_{toair} = H_{fan} + (H_{motor} - H_{fan}) * f_{motortoair}$$

While not discussed in the fan section, I assume it's the same logic as pumps. Any shaft power is eventually realized as heat to the fluid due to friction losses. I'm not actually a fan fan of that because in the real world, you're not controlling to those losses because that heat would be added after any kind of discharge air controller.