[Sheripoms]

Hi everyone
I am just starting to dabble in alternative energy. But it occurred to me if this product like this
http://www.amazon.com/PowerPot-Devi...&qid=1413314021&sr=8-2&keywords=the+power+pot is available that can change heat into energy to charge cell phones. Why on earth can't a wood stove turn heat into other forms of energy?
I hope the link works. If not go to amazon and search for Powerpot v

 

[TnAndy]

Why on earth can't a wood stove turn heat into other forms of energy?

You can generate electric power from a wood stove now....simply put a bunch of TEG modules on your stove and you're in business. They use a principle of physics known as the Seebeck Effect (as does the one on Amazon) which converts heat energy to electrical energy.

The downside is they are fairly low in efficiency, and fairly high in cost.

For example, this website: http://www.tegmart.com/ has a 45 watt version for $527. Nice little unit, ready to go with USB and cig lighter plug. But if you figure out the price per watt (nearly 12 bucks), you'll quickly see that's quite high compared to solar panels at a dollar/watt (or less).

To compare to a solar panel: Say you bought a 200w solar panel for $200. And it produced power for 4 hours today....10am to 2pm, and it was a nice day. You got 800watt hours. Then you also bought one of those 45w stove devices. Divide 800/45 and you'd have to run the stove 18 hours to give you the same output, for close to 3 times the cost.

The upside is you can generate a small amount of power when the sun isn't shining but the wood stove is cooking.


Now, research IS going on that hopes to vastly increase the heat to electric conversion. This guy, for example: http://phys.org/news/2014-03-electricity.html is on a path that might up the efficiency quite a bit, and make direct conversion practical.

But for right now, these devices are more of a novelty item, used for low power requirements, like the 5w one on Amazon.

 

[TnAndy]

But now if you're REALLY interested in a cool device to generate electrical power from wood, there is a guy in Florida (sorry, don't have the link anymore, you'll have to hunt around the net for his website) that sells a pre-packaged "dumpster" unit for generating power in remote, or disaster area ( like after a hurricane ) that have LOTS of wood scrap.

He took one of these long, open top, construction debris dumpster units, then lined the bottom and sides with ceramic panels ( like fire brick in a wood stove ) that have freon lines in them. You dump loads of scrap wood in it, and start burning it.....it even has fans to force air in from the ends to force the wood to burn at a high temperature and rate.....and that heats the freon in the ceramic panels.

That goes to a GE gas turbine that spins a good sized generator ( I can't remember the size, but it's like 50,000w or so), the freon is then condensed again into a liquid with big condensers on the unit, and flows back into the ceramic panels to get boiled again by the fire in the dumpster.

Whole thing is mounted on a large trailer, ready to be towed into the woods or your local disaster area where there is tons of burnable building debris to get rid of, and at the same time, a lack of local electric power.

It was pretty cool.....pricey.....like 1/2 million bucks....but cool !

I looked into them for a local sawmill that generates a LOT of wood scrap, and was looking to do something along the lines of a conventional wood fired boiler/electrical generation.

 

[gpforet]

I'm looking at building such a device to attach to my wood burning stove to generate a little power during the winter. The only downside is that TEG devices rely on a temperature differential. The greater the difference, the more power. I'm planning on cooling the cool side by using a small CPU liquid cooler and routing the fluid thru the sump of my indoor aquaponics system to help heat the water. If that doesn't provide enough cool sink I may place a small heat exhanger against a single pane window to sink the heat that way. Right now it's just an idea and I've got my hands full with my solar PV project.

You can generate electric power from a wood stove now....simply put a bunch of TEG modules on your stove and you're in business. They use a principle of physics known as the Seebeck Effect (as does the one on Amazon) which converts heat energy to electrical energy.

The downside is they are fairly low in efficiency, and fairly high in cost.

For example, this website: http://www.tegmart.com/ has a 45 watt version for $527. Nice little unit, ready to go with USB and cig lighter plug. But if you figure out the price per watt (nearly 12 bucks), you'll quickly see that's quite high compared to solar panels at a dollar/watt (or less).

To compare to a solar panel: Say you bought a 200w solar panel for $200. And it produced power for 4 hours today....10am to 2pm, and it was a nice day. You got 800watt hours. Then you also bought one of those 45w stove devices. Divide 800/45 and you'd have to run the stove 18 hours to give you the same output, for close to 3 times the cost.

The upside is you can generate a small amount of power when the sun isn't shining but the wood stove is cooking.


Now, research IS going on that hopes to vastly increase the heat to electric conversion. This guy, for example: http://phys.org/news/2014-03-electricity.html is on a path that might up the efficiency quite a bit, and make direct conversion practical.

But for right now, these devices are more of a novelty item, used for low power requirements, like the 5w one on Amazon.