Thermoelectric generator - candle and cold water

[twinbeard]

You guys are totally on the right track with using these to cool down photovoltaic, then move the heat away in water pipes.  I came here to recommend that, but you guys are already thinking correctly:)

[Pirate88179]

Twinbeard:

ARRRR...good to see you again.  I believe there are many new uses we can find for these things.  I just watched a vid on the tube where a guy charged his cell phone while camping using the campfire and some cold river water.  As mentioned by someone above, not efficient but, it got the job done when nothing else would.  Even works at night or on a cloudy day.

Bill

[Magluvin]

Well, solar panels work better when cool vs hot, so we could mount these on the back of the solar panel(hot side), and the cold side could transfer the heat to water pipe system for producing hot water.

So now our solar cells work better, we also get power from the Peltier's and hot water to boot. All in the same square area. ;] Just a little thicker. ;]

MaGs

Lol, then we can take the power stored from the peltiers, power that we collected heating water, for free, ;] , then use that stored power to pump the water in cycles. So now we have a solar panel, that heats water, not using the power from the solar panel to do so, and we get water cycling energy from the peltiers.

Just trying to think of a logical use for that energy. Sounds like a marketable combo system, while increasing the solar panel efficiency as a plus, plus.  ;]

maGs

[Magluvin]

Twinbeard:

ARRRR...good to see you again.  I believe there are many new uses we can find for these things.  I just watched a vid on the tube where a guy charged his cell phone while camping using the campfire and some cold river water.  As mentioned by someone above, not efficient but, it got the job done when nothing else would.  Even works at night or on a cloudy day.

Bill

Son, go out and chop some logs for the fire, I think we will run the A/C tonight. ;]

Use the fire to generate, to run a peltier A/C unit.

That 400w jobby, I bet would blow some really cold air with the right combination of heat sinks and blowers. My little 40w produces some cold air. That 1 400w module could probably surprise you.  My buddy want to try to make an ac for his elcamino. We have to test larger or multiples to see what happens. The peltiers are not expensive to play with.

MaGs

[conradelektro]

I am very happy with the many ideas presented in this thread.

Pirate: cold window. I have a "cold window" next to both of my stoves (see photo). Some Peltier elements with the cold side against the window and hot water or steam from a kettle through some pipes to a heat exchanger on the hot side of the Peltier elements. Have to think about the heat exchanger (where to salvage it from) ? Since I do not want to glue something against the three glass windows, the whole thing should only lean against the cold window.

DreamThinkBuild: I should have found your Pyro Photo-Voltaic thread in order to use it, sorry. The idea with the frozen cup works here in winter by just putting it outside in the freezing weather for an hour. Good idea to use solar cells in combination with the candles. Are there solar cells that like infra red as a light source? I guess the solar cells rather lean towards ultra violet light?

Magluvin: Yes, that is right, Peltier elements on the back side of solar panels. Wood: around here you could get broken down trees for free as long as you remove them from the woods by your self. A lot of work, a few liters of gas for the transport, but almost for free. A friend of mine gets the cut off (mostly bark) from a saw mill for free. He just has to collect this low grade wood. He cuts it and uses it for his stoves. Again, some work, but his heating is cheap. When I was a kid, people used to cut down bushes and make brushwood bundles for the kitchen stove. All this will come back with the shrinking world economy.

I ordered four 40 mm x 40 mm Peltier elements sustaining 200° Centigrade from eBay. There are better ones, but they cost more. For a home project it would not matter to use a few more as long as they are cheaper than the high power stuff. Once we have a good and practical design, it might be worth to get some really good ones for about 60.-- Euro each (60 mm x 60 mm, 250° Centigrade).

I will also get some heat resistant and heat conducting paste and some heat resistant and heat conducting glue (a bit expensive).

Is it better to press the heat exchanger against the Peltier element? If yes, it is not so easy to come up with a design that does not heat the cold side as well. Something has to press against the hot side and the cold side and this something will conduct heat away from the hot side and heat to the cold side via a support structure.

How strong is the Peltier element mechanically? The ceramic plates seem to be brittle and gluing something onto them seems to be the only good way. The brackets I built do not seem to work very well. The brackets can not grip well because the space in between the ceramic plates where the metals are is very limited (short circuit has to be avoided, only one ceramic plate should be touched by the bracket).

As some said, it is not straight forward to build something good and practical around a Peltier element, and it becomes more difficult in case one wants to combine a lot of elements. Glue, paste and heat exchangers pressed against the element seem to be the standard design choices. There are elements that support open flames at 1000° Centigrade (of course they are expensive).

Greetings, Conrad