Maximum thermoelectric energy conversion efficiencies are calculated using the conventional ''constant property'' model and the recently proposed ''cumulative/average property'' model (Kim et al. in Proc Natl Acad Sci USA 112:8205, 2015) for 18 high-performance thermoelectric materials. We find that the constant property model generally predicts higher energy conversion efficiency for nearly all materials and temperature differences studied. Although significant deviations are observed in some cases, on average the constant property model predicts an efficiency that is a factor of 1.16 larger than that predicted by the average property model, with even lower deviations for temperature differences typical of energy harvesting applications. Based on our analysis, we conclude that the conventional dimensionless figure of merit ZT obtained from the constant property model, while not applicable for some materials with strongly temperature-dependent thermoelectric properties, remains a simple yet useful metric for initial evaluation and/or comparison of thermoelectric materials, provided the ZT at the average temperature of projected operation, not the peak ZT, is used.

Waves and Beaches-for W Bascom To watch the light traveling along the ocean crests, the shadows criss-crossing in troughs, and imagine motion traveling though time; to translate motion to depth of water, current, waveto infer from these an island, seven thousand miles away: cool respite for the mind assigned to predict how the waves from the H-bomb test would travelfirst the light that blinds, the x-rays that burn, then the shock of the blast-then the deafening sound. the island Elugelab, gone, a spreading plume-Eniwetok atoll a torn wound-and if landslide, the tsunami you computed beginning its thousands of miles.

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