TEG thermoelectrics

Found a maker of TEG devices that i had not seen in my previous searches. This looks promising.
We have a project to integrate two 100W TEG modules on an indoor wood burning heater.

We will be calling the manufacturer to find out if it will be able to run at 48vdc for battery charging. Temp readings from the surface indicate that 450-550 deg. F surface temps are not a problem to maintain.

After this step, i will source an appropriate radiator for mounting outside. These are usually built from extruded aluminum.

A circulator and control, some tubing and non toxic antifreeze with a pressure relief are on the list.

We will likely use a pair of Devilwatt TEG modules or this new device available in March!

http://firevoltsystems.com/firevolt-superteg-thermoelectric-generator-100-watt-12v-24v/

They also build rocket stoves with integrated TEGs.

http://firevoltsystems.com/firevolt-600w-thermoelectric-generator-full-system-with-stove-600-watt-core-instove-60l-electrical-plumbing/

Here is the stove. A good, high efficiency unit.
The design involves removing a heat shield and fabricating a conductive riser to the inside of the shield, which will make contact between the heat shield and the firebox, then attatch the TEG modules to the heat shield.

Shield surface temps were 400-500 deg.F with a rager going. This should allow higher operating temps over the course of a heating day eith moderate fire for the TEG hot side and not exceed the modules 850 deg. F limit.

I will keep progress posted here, as interest is high (mine!), and its a fun project.

Ok, i cant add a photo for some reason. Ill try later.

Cool Frank, looking forward to hearing more.

This is an interesting alternative to wind as a backup for your solar system.  A 600W unit, if it can be setup to charge a 48V battery bank, would be a nice boost to charging batteries in the winter (when sun is scarce and the angle is low) albeit not at a bargain price.  They claim the units will be available in March 2018, I am wondering if they are behind schedule and forgot to update their website or if they actually meant 2019?

Those are some very interesting stoves. One supplies hot water as well as electricity.

An update, i have been sending email and making calls to the manufacturers of Devilwatt and Firevolt systems, their distributors etc., for weeks to no avail. I have not had so much trouble trying to accquire a device since we sourced LED grow lights last season.... aside from these two experiences, cash on the barrelhead is a filled order!

Has anybody contacted these companies recently? Man i could use a phone number!

It is just wild that these companies do not publish a way to speak directly to them, i am amazed.

It did turn up some nuggets. It appears that a company called thermonamics makes the $799 firevolt 100w superteg and sells them possibly as low as $100 apiece in quantity.

100 watt, TEG-HL 100-12/24

http://www.thermonamic.com/products.asp?cid=412

The company makes a wide array of tegs, 200-1000w and 48v, but even they have not replied on whether TEG HL-100 can be series stacked to 48v.

If i had the money, id order a case and label it the frank li firewatt and and answer the phone a couple times a week!

@Frank - here's what someone who appears pretty knowledgeable has to say on the topic:

https://electronics.stackexchange.com/questions/26625/teg-in-series-require-power-balancer-align-adapter

TLDR; series operation shouldn't be a problem unless you're trying to wring every last bit of performance from the devices.

Phil Stevens wrote:@Frank - here's what someone who appears pretty knowledgeable has to say on the topic:

https://electronics.stackexchange.com/questions/26625/teg-in-series-require-power-balancer-align-adapter

TLDR; series operation shouldn't be a problem unless you're trying to wring every last bit of performance from the devices.

Thanks, Phil.
That was a good read.

I have noted the use of mppt controllers and considered exploring switching or other voltage boosting. Ideal is a 48v brick and i do not mind using two 24v modules, but i keep seeing 24v as the higher option in a unit or units in series and am hoping that this is not the ceiling for being an easily integrated appliance.

The "specsheets" for these are lacking, they are more like feature sheets.

Integration wise, the teg unit will be cooled via convection into the basement below the ground floor heater and i would like to research for heat exchange to dhw pre heat. A 20 gallon buffer tank heat exchange coupled to the cooling loop and feeding the ao smith 40 gallon electric water heater. The home is net zero grid tied with pv and battery backup suitable for long term power outage and transition to off grid.

I have been following these for some time, I think adding to a motor  exhaust pipe would be an ideal application for the waste heat.

I have seen a guy get a barrel of sawdust to burn for like 6 hours, I think that combined with this would make for a good combo.

I have been thinking about using cooking oil that can be heated to 300 degrees with a rocket stove, then using that heat in that oil to run one of these.


All kinds of options.

I have been playing with teg/tec for about 15 years.  My father-in-law was a truck driver and I got ahold of a tec unit from his cooler/warmer that the temp switch went bad in.  I've built a couple for on the go power from some teg cells I got from a company in W.V.  I have a vegetable oil stove that I use to heat one that is 14v at 2 amps.  The first picture is from a kerosene powered fan I made from a trucker cooler.  I have demonstrated it for 14 years at engine shows and sustainable energy shows. The second is a 14v at 1amp at 250f delta t.  I use it for camping on the Coleman stove with a pot of water on top for cooling.  The tec's we made a chicken water cooler and heater depending witch side you flip up.  It takes 60 watts to fully power it, but works good for me with a 50w panel.  

Christopher Shepherd wrote:I have been playing with teg/tec for about 15 years.  My father-in-law was a truck driver and I got ahold of a tec unit from his cooler/warmer that the temp switch went bad in.  I've built a couple for on the go power from some teg cells I got from a company in W.V.  I have a vegetable oil stove that I use to heat one that is 14v at 2 amps.  The first picture is from a kerosene powered fan I made from a trucker cooler.  I have demonstrated it for 14 years at engine shows and sustainable energy shows. The second is a 14v at 1amp at 250f delta t.  I use it for camping on the Coleman stove with a pot of water on top for cooling.  The tec's we made a chicken water cooler and heater depending witch side you flip up.  It takes 60 watts to fully power it, but works good for me with a 50w panel.  

Nice projects you have there.    I have been thinking of combining a teg with graphene to help dissipate the heat better.     Graphene thermal is  twice as conductive as copper.

These are the cheapest I've found

http://www.thermonamic.com/products.asp?cid=363

Been trading 7+ years, I've had my unit 5+years and in use daily (in winter)

Hi Mart. I am definitely interested in the graphene and am in the prosses of trying to make it at home.  For now I use a mass to offset heating up to quickly.  My first couple I let the smoke out.  We also use the supper caps to store and buffer.  Have any of you played with a joule thief circuit to jump voltage?   I have been stealing the parts out of blown florescent curly type bulbs.  They work, some better than others.  I use them to jump the voltage from a tec from 1V to 2v, then I can charge batteries or caps with them.

Christopher Shepherd wrote:Hi Mart. I am definitely interested in the graphene and am in the prosses of trying to make it at home.  For now I use a mass to offset heating up to quickly.  My first couple I let the smoke out.  We also use the supper caps to store and buffer.  Have any of you played with a joule thief circuit to jump voltage?   I have been stealing the parts out of blown florescent curly type bulbs.  They work, some better than others.  I use them to jump the voltage from a tec from 1V to 2v, then I can charge batteries or caps with them.

Robert Smith on youtube is the guy for graphene.

->  
https://www.youtube.com/playlist?list=PLbQqm4rNo625Etz4INo2wP2X4sxgwDyNN


I worked about 5 years making Bedini battery chargers, and varients of the Joule theif.

If you like that sort of thing, I recommend this channel ->

https://www.youtube.com/user/lasersaber

He has super projects that will blow your mind   cutting edge.