someone else on YouTube tried to do this practically throughout a day and found that the charging current just wasnt enough to compensate for the power he lost riding the board. he only regained about 10% power after sitting in a field for hours with the solar panels.
The guy in the video is using a MPT-7210a MPPT solar boost controller. Those are ok, seen plenty of reviews on them. But they do have a slightly noisy cooling fan.
Recommend the CTK300-II MPPT solar boost controller and a much bigger portable panel. Also it helps tremendously if you can keep the solar panels aimed directly towards the sun. Just having them flat on the ground decreases the wattage.