I worked with airjaldi.org in the Himalayan mountains for a few months. They use a solar+mains hybrid to power wifi mesh nodes, but the issues they had to work

I worked with airjaldi.org in the Himalayan mountains for a few months. They use a solar+mains hybrid to power wifi mesh nodes, but the issues they had to work around (variable voltage inputs, using locally available components) might be applicable for your laptop charging use case as well. Here are some design specs. Good luck! http://drupal.airjaldi.com/node/69 http://drupal.airjaldi.com/node/69