One major annoyance of using TEG's (from my own experience) is that they need heat to flow through the TEG rather than "heat it up".. so if you don't have a way for the heat to flow through the TEG (such as a fan or heatsink on the opposite side of the TEG -- the "cold side"), you rapidly end up with a situation where both sides of the TEG are roughly the same temperature and as a result you end up generating very little power. So if the wood stove heats up the ambient air around you, then the result is the efficiency goes down tremendously. These things are more suited for places where you have a very high temperature and a cold sink -- like the outside surface of a metal chimney in your cabin in the woods type thing -- such as outside, where you have the greatest sustainable delta T.