Thermoelectric-based power generation systems and methods

A power generation apparatus comprising:

• at least one exhaust tube configured to contain a flow of exhaust fluid, the exhaust tube having a high temperature end, a low temperature end opposite the high temperature end, and a middle section between the high temperature end and the low temperature end during operation of the waste heat recovery apparatus;
• a first plurality of thermoelectric elements connected to the high temperature end, each thermoelectric element of the first plurality of thermoelectric elements having a first temperature differential along a first length of the thermoelectric element during operation;
• a second plurality of thermoelectric elements connected to the middle section, each thermoelectric element of the second plurality of thermoelectric elements having a second temperature differential along a second length of the thermoelectric element during operation;
• and
• a third plurality of thermoelectric elements connected to the low temperature end, each thermoelectric element of the third plurality of thermoelectric elements having a third temperature differential along a third length of the thermoelectric element during operation;
• wherein the second length is longer than the third length;
• and
• wherein the first length is longer than the second length.

A power generation apparatus comprising:

• at least one exhaust tube configured to contain a flow of exhaust fluid;
• at least one bypass region extending through the at least one exhaust tube, the at least one bypass region having a low exhaust fluid pressure drop;
• at least one coolant conduit configured to contain a flow of coolant within a first tube, the at least one coolant conduit comprising a second tube enclosing at least a portion of the first tube and a thermally conductive material disposed between the first tube and the second tube;
• at least a first shunt extending from the at least one exhaust tube;
• at least a second shunt extending from the at least one coolant conduit and in thermal communication with the second tube;
• and
• at least one thermoelectric element thermally connected between the first shunt and the second shunt.

A thermoelectric system comprising:

• a plurality of thermoelectric elements;
• at least one cooler side shunt and at least one hotter side shunt in thermal communication with at least one of the plurality of thermoelectric elements;
• at least one heat exchanger in thermal communication and physically integrated with the at least one hotter side shunt;
• and
• wherein the at least one heat exchanger is substantially electrically isolated from the at least one thermoelectric element.