Recent concepts in thermoelectric power generation

The development of economic thermoelectric generators for waste heat recovery has become an increasing research focus over the past a few years. Traditionally, attempts to improve their economic viability have concentrated primarily on improving the conversion efficiency by increasing the figure-of-merit of thermoelectric materials, with only marginal successes. This paper explores the possibilities and implications of alternative approaches in an attempt to improve the economic competitiveness of thermoelectric generators based on currently available materials (i.e., with ZT/spl sim/1). Novel concepts which provide alternative approaches to overcome low efficiency drawback are discussed and examples presented, typical of which include high-power-density thermoelectric generating modules; symbiotic systems for co-generation of heat and power; high efficiency heat-recirculating thermoelectric-combustion systems and thermoelectric microgenerators.