To get a hot meal on the trail, campers must either lug a propane stove and fuel canister or try their luck on the uneven heat of a campfire. Designers at BioLite in Brooklyn have created a new solution. Their lightweight wood-fired CampStove not only burns as hot as a propane one but also converts waste heat into electricity to charge any USB-powered gadget.
Campers pack a small handful of sticks into the bottom of the stove’s dual-walled steel combustion chamber and light the fire. One batch of kindling can boil a liter of water in five minutes.
A one-inch blower fan pushes fresh air into an angled vent near the bottom of the stove and circulates it counterclockwise through a half-inch gap between the combustion-chamber walls. The inner wall is perforated with 34 holes near the top and 11 more near the bottom. As air heats up, it expands and enters the combustion chamber to feed the fire.
A custom thermoelectric generator (TEG) converts heat into voltage. On one side of the TEG, a 1.5-inch copper-and-aluminum heat probe extends into the fire. On the other side, the fan cools a set of heat-sink vanes. As electrons move between the hot and cold sides of the TEG, they are directed into a set of wires.
Electrons pass through the set of wires and into a printed circuit board, which contains a processor. The processor evens the current and sends power to the blower fan, a battery that holds reserve power for the fan, and a USB-connected device. The CampStove produces a steady two watts of power, enough to provide an iPhone with 60 minutes of talk time on a 20-minute charge.
Dimensions: 8.25 inches by 5 inches
Weight: 2 pounds, 1 ounce
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.