The Voltaic system is designed to charge a laptop off of this durable, small 20W panel. The panel works well, but the Voltaic battery struggled to hold a charge, and had a difficult time fully charging off of the panel itself. This is a big issue since the Voltaic only charges its own battery. The whole system is flawed. Voltaic is on the right path, but their system needs refining to make the panel both more effective and easier to use.
That said, the panel is efficient and durable in its design. It is also lightweight and has a simple system for charging Mac products off of the battery. These positives made it our preference over the X-Dragon 40W for a laptop-compatible panel.