Heater floor outlet ducts block off mod for better driver comfort and increased range

Here is a very simple mod to increase driver comfort and range in cold Winter weather. The dash vents can all be opened or closed by any amount manually but the floor vents are taking 3/4 of the heat away from the driver to warm people that are not there. Since I am a solo commuter with 40 miles each way and 10F temps, I used some scrap pieces of foam material and cut them to fit in the heat outlet ducts for the right front and both rear outlets under the seats. Now all of the heated air is directed to the driver's feet. It is easy to feel a pronounced airflow and warmth at the driver's floor outlet on fan speed 1.

It's simple I like it.
Even with unlimited diesel fired heat not impacting range this could make the low 0.2L per hour of fuel burn setting provide plenty of heat.

I would like to figure out a mod to run those vents to the battery for both warming and cooling purposes.

Thanks!