Tim_RFor example. SunJack is quite popular, their 5W model has almost the exact same square inches of surface area at 13X6 inches as this model (80 square inch for this, 79 for SunJack's 5W).
If you want to get 14W from SunJack you will need their 31X9 panel (unfolded) which is a whopping ~280 square inch.