A stovepipe thermoelectric generator. The unit fits in a stovepipe of a coal or wood stove. At least one thermoelectric module is sandwiched between a hot side fin unit with fins extending into the flow of exhaust gases and a cold side fin unit with fins cooled by forced room air. A damper controls exhaust gas flow through a heat chamber, directing the exhaust gas through a generating side and a bypass side depending on a temperature indication. This prevents heat damage to the thermoelectric module. At least one fan is provided to force room air through cooling fins of the cold side fin unit An electric circuit is described for providing power for the fan and providing additional electric power for purposes such as charging a battery.