I'm sure it is possible to do (and probably has been done by hobbyists) but the there are still too many issues with that concept, mainly the cost. It is still not cheap to be hybrid or electric. What money is saved on gasoline is just spent up front on the costs of all those batteries and such. Doing it just to be green isn't really a valid argument either, as the waste created to produce those batteries is pretty significant as well. And then, how does one charge that van? A simple 120 volt outlet wont do the trick, and it would consume a lot of electricity each day (the power grid in the USA cant handle even 10% of our population plugging in electric vehicles each night). There are super charger stations, but not enough (yet). Solar can not charge up a vehicle's battery system in a timely fashion, or reliably.
Still, I hope to be alive when the time comes that a person can have a vehicle 100% off-grid. No need for gas station or electrical outlets. We are so close already, but not all the way there. It wont take long, but once we get there the vans will cost too much for us common-folk for another decade or so. A fun day-dreaming subject nonetheless.