For the rest of the weekend, we ran—rather fitfully—on nerd power. The HYmini needed wind speeds of nine miles per hour to generate electricity, so we attached it to the car window and drove off on our adventures, shouting over the whirring of the plastic propellers—never mind that it ran my cell phone for only 20 minutes. We geeked out over the solar backpack, which, with all its wires and batteries, seemed better suited for a space walk. "You can wear it hiking," I chirped, filling it up with sandwiches. "Oh, my goodness," Win said, taking one look at my cell phone nestled in the strap charger pocket. "You'll be wearing it hiking."

But if your wilderness needs don't include 1800-watt hair styling, the solar stuff is bomber. Win snatched up the little Solio like it was his blankie and carried it on a two-week trip down the Grand Canyon—for the first time, he could lie on his boat and listen to music for more than one night. I made off with the little Brunton, which seemed nearly indestructible.

Back home, I vowed to stop using the wall outlet. The HYmini was out; I drove around for days trying to recharge it before realizing that once you suck the device dry, you have to plug it in: It can't recharge from scratch on wind.

So mostly I rolled on solar. Some days, when I'd been diligent with my outdoor charging chores—shifting the panels to face the sun, making sure they were slanted 45 degrees—living on sun juice was easy. Others, not so much. The little Brunton survived a dousing when I dumped a full water bottle in my purse, only to warp when I left it baking for six days on the griddle-hot dashboard of my car. (Note: Dashboard frying not recommended, nor are hot surfaces much above 120 degrees.) The big Brunton soldiered on doggedly. Still, after charging it for 36 light-filled hours, it ran my laptop for six, a sobering reminder of just how much electricity fire-hoses out of our outlets every time we plug something in.

In the end, I simply stopped using my gadgets so often. Now when my charge runs out, I'm done for the day. But whatever nano­wattage of self-reliance I can eke out feels like opening the window and letting in a little puff of freedom—just enough breeze to fruitlessly spin my teeny turbine and make me feel partially, crucially in control of my fate.