200w is an instantaneous measure, not a daily measure. I would guess just over 1kw/h generated over the course of a day - between the panels not being at the correct angle, clouds, and just how long the sun is up that seems reasonable. You could get a large SUV up to maybe 3 with the most efficient panels in the desert.

I pointed out a semi because for long distance shipping they don't use much power (they get as much as 10mpg - but I don't know how to turn that into watts) and because of that long trailer they could potentially be close to energy neutral around mid-day (though only for a couple hours during ideal conditions).