If there’s one thing inconvenient about solar panels it’s that they’re huge and impractical to bring around with you. Well the folks in OS, Japan, have come up with something called the Mobile Solar Unit GSR-110B – a portable power generation system that makes use of solar power to recharge its batteries. What’s interesting about this device is that it has a retractable solar panel that users can easily pull out when they need to use it, and put it back in when they’re done or they need to transport the device. The system provides up to 40W of power through a 12V socket and can be linked with another unit to double the output. Weighing only 3kg when rolled up, it’s not going to be much trouble bringing this device around especially in disaster areas or for outdoor events. It is available for purchase in Japan right now for $725. Hit the break to watch a video describing the Mobile Solar Unit: