Creatively combining old tech with new tech
One of the aspects of permaculture is taking a time tested tribal means of survival and community skills and adapting it by using modern technology and in the synthesis come up with better ways to utilize resources, save time and effort, and produce more work from the same ordinary devices.
One such idea is to take the rocket stove that you only use for cooking or heating, and use it in novel ways. One idea that's being tried is coupling a TEG or a peltier device to generate electricity. A TEG uses the difference in temperture to generate a small amount of energy, and then that could be used to recharge an electrical device of very low voltage and amperage.
Sure, a solar cell might do this easier, but the village may not have a solar cell recharger, but they can make a rocket stove, and might have a TEG. I agree that it seems the best way currently for no waste of resources is a solar charger. There is one company that is marketing the device for 3rd world nations and has a working model: [link to www.biolitestove.com
Such a device would work best when the temperature is greatest but not interfering with the recharging process. An experimenter is working on the idea here, but he's not getting a good heat transfer due to the insulative properties of the brick versus a standard metal rocket stove. A brick rocket stove however is the easiest rocket stove to assemble since all you need is clay, grass, a mold, and time to produce them.
[link to www.youtube.com
Another example of a multi-use idea is to use a solar oven for water purification. Wood (or an alternative fuel like dried animal dung) may not be in abundance. The solar oven might be used to generate a sustained heat source for cooking, but also might be used at other times as a way of heating up the water hot enough to kill many bacteria and parasites. Of course it still requires filtration. A cheap means of doing this in the heat of summer is merely placing water in two liter soda bottles on rooftops and using the roof tiles to heat up the water.
[link to solarcooking.wikia.com
The solar oven can also work as a food dehydrator.
A solar oven that's pointed at the sky at night in certain circumstances can lower the ambient temperature (several degrees above freezing) and generate ice. That might be something very important for a variety of reasons. See the article below for three alternative refrigeration methods.
[link to www.provident-living-today.com