Solar Cells recharging Prius batteries?

I was thinking about a way for people to recharge their Prius or other plug in hybrids or Teslas (all electric) while at work or (whenever they are parked in direct sunlight).

One way would be to purchase a solar array the size of your front or back windshield. Then to park your vehicle in the sun (facing the sun during the day if possible). Then with the solar array inside on your front dashboard you could be recharging your car while it was parked literally anywhere in the sun. This might be especially useful during the summer months worldwide when there is more sun.

It might be a little bit of a pain to remove the solar panels but if you get the flexible ones you could use this solar panel array like a sun screen like you put in a front window with it's silver side facing outward during the summer months or it's black side facing outward during the winter to warm your car. If it was a flexible array of solar cells and it was plugged into your battery the solar array could charge your battery while you were at work (or wherever) and you might just roll it up and set it on the seat next to you when you weren't using it.

With the price of gas and diesel going up around the world this is going to save you a lot of money in the long run because of the problems in Iraq and Syria causing gas prices to go up everywhere.