Powering Your Gadgets in the Wilderness
In discussions with other gadgets users, often the problem of getting extra power comes up. Particularly when you are away from power outlets for prolonged time - e.g. on the nature hike. Two "miracle solutions" always inevitably come up - using muscle power ("wind-up chargers") or using solar power. On first look, they appear to be perfect. However, they have very significant shortcomings in reality: