In the typical urban commute, it’s one person per car. Single-seater three-wheelers thereby dominate most city car designs. Daniel Julier's '3Wheeler' speaks to this three-wheeled design, but adapts it into a 1+1 concept, which means in a pinch you can jam another person in the rear, erm, rear seat.
The single rear wheel opens up some room that can be used for a small storage space as well. The '3Wheeler' is meant to be powered by hydrogen, but it can also capture energy while going downhill to be used when going uphill for a boost.