
For those of you with woodburning stoves—I know at least some of you have them, either in your house or heating your shop—the Ecofan is a clever, energy-free way to help circulate the heat. You place the Ecofan on top of your stove, and as the stove heats up, the blades begin to turn, distributing the hot air into the rest of the room. The hotter your stove gets, the faster the blades spin, up to a maximum volumetric flow of 150 cubic feet per minute.
The Canadian manufacturer, Ontario-based Caframo, claims the better circulation means you'll have to burn less wood to keep the place warm. And unlike a conventional blower, the Ecofan is completely silent.
Now for the big quesiton—how the heck does it work? While there are several reviews by North Americans on YouTube, we'll let this British guy explain it to you because Brits generally sound smarter. (Except when they're burning our White House down.)
Comments
Thats cool - I'm loving they've kept it really simple.
I worked with a guy who developed a similar system for a local firm - http://www.woodsman.co.nz/products/ferva
"Thermal bridging" is actually a phenomenon that reduces this gadget's performance. The thing in the gap is a thermoelectric device; it uses the Seebeck effect to convert a temperature difference into an electric potential difference. You can also think of it as converting a flow of heat into a flow of electrons. The screws that hold the halves together do thermal bridging: they move heat from the bottom to the top without it passing through the thermoelectric device. The heat that passes through the screws is thus not converted to electricity.
Looks like that's using a Peltier effect to generate power for an electric fan. (http://en.wikipedia.org/wiki/Thermoelectric_effect )
I think the purely mechanical ones using a Stirling engine are much cooler (so to speak) http://www.vulcanfan.com/
more practical would be to build it into the hood, so less fingers will be chopped