Calculating Size of a TEG to Power Load 'xyz'

http://www.acronymfinder.com/TEG.html

Well alrighty then. TEG = Thermal Electric Generator. Using the variable of thermal values,also known as the Delta, generally hot and cold(er) to generate electrical current, which is then utilized by the target device which has a load = 'XYZ'. 'XYZ' is currently undetermined.

I hope that helps.

By size, do you mean, 'leading dimensions'? _{The question is in a mechanical engineering section, after all.}

Probably too huge and expensive to be worth the trouble.

I'd be inclined to start here, at the fifth in a series "Campfire Generator".

You can then work backward through the series as you see fit, for additional details.

As a rough guess TEGs are 10% efficient, (many are less, a few are more), but having a good heat sink and optimum input temperature are both important -- otherwise the efficiency can be much lower.

I'd guess that the input into the Campfire Generator was about 800 watts (typical for a gas stove burner) and the net output was 0, after deducting for running the cooling system.

I read somewhere that an automotive system was available to replace an alternator, for about $3000. Here's an article on that sort of thing.

Check E Bay for the for the devices themselves, most of which are rated for power dissipation, rather than for output.

Yep

Find out what your temperature difference (delta) is, look up CARNOT cycle and work out what the theoretical efficiency will be, assume a whole lot of extra losses and working friction, double the losses you think you'll get, and then see if the project is still viable.

You can also use that old faithful equation E=mcΔT to see how much energy you actually have available.

Calculate twice, build once.

As K_Fry indicated, most TEGs have an efficiency of 10% or less. That means you need an input power (heat) of 10kW or more to get an output of 1kW. Unless you have free heat as a byproduct of some other process, it does not make sense to even try.

Don't forget you need power to run the circulation pump...

Clearly a 10% efficiency return is minimal at best. The heat source is a constant by-product of a process running 14+ hrs a day 7 days a week. That is pretty much the reason for this endeavor. We, my business partner and I, were very intrigued by a co-generation water heater we saw a few years back. We are determined to develop our own co-generation system that has a practical use and that the average person can understand. I am onboard with TEG's as 'middle man' if you will, and have a pretty good understanding of the process (electrical background) but I am still in the dark as to how much electrical power can be produced by the products currently on the market. I am still in the begining research phase and don't yet have all the requirements for each element of the complete system. Once I know what output is achievable, when taking into consideration the temperature at the heat source(the only known factor at this point) the back end can be customized to fit the max output.

A question if you will. Will a greater temperature differential increase the output of the TEG?

Thank you for your input. I will be pouring over the website(s) and books that are recommended.

"Will a greater temperature differential increase the output of the TEG?"

Absolutely, as long as you don't exceed the temperature limits of the TEG. In fact this is true for any heat engine as well.

Which brings to mind: Have you investigated a Stirling Engine/Generator system? The initial investment would probably be higher, but the greater efficiency might well pay off rather quickly.