Im still struggling to see how this will work...
Why couldnt you just turn the box off and drive.... it cant stay on all the time surly as it would drain the battery, and what if you needed to disconnect your battery, would a police man turn up 5 mins later and haul you away on suspicion of fraud? How would it differentiate between me say working on my car for 2 hours, or doing a 2 hour round trip with it off and reconnecting it...
What about when you go through long tunnels.....
Questions questions, all comes down to money though, they COULD do the environmentally friendly thing and get everyone off the road, but then they wouldnt have any money, conflict of interest!