For two years we've looking for the right nanotech prize.  A paper in the January 10 Nature suggests that a prize for thermoelectric materials might be a great nano prize and a good fit with the Energy & Environment suite of prizes in development.

"Approximately 90% of the world's power is generated by heat engines that operate at 30-40% efficiency, such that roughly 15 terawatts of heat is lost to the environment.  Thermoelectric modeules could potentially convert part of this low-grade waster heat into electricity...Here we report the electrochemical synthesis of large-area, wafer-scale arrays of rough Si nanowires that..show promise as high-performance, scalable thermoelectric materials."