Voltaic has created a case/solar charger for the iPad and other tablet devices. My question is how practical is this case when it takes 10 hours of direct sunlight to charge the solar panels enough to charge my iPad. Is the light from my office window direct enough or does it have to be out in this oppressive heat directly? The solar panels are covered with a clear, UV, scratch resistant, and waterproof coating so they are supposed to be durable. (In a student’s backpack, really?) Plus the device is 300 dollars. Wow, toys are expensive these days.