  We demonstrate high-temperature thermoelectric conversion in InAs/InP
nanowire quantum dots by taking advantage of their strong electronic
confinement. The electrical conductance G and the thermopower S are obtained
from charge transport measurements and accurately reproduced with a theoretical
model accounting for the multi-level structure of the quantum dot. Notably, our
analysis does not rely on the estimate of co-tunnelling contributions since
electronic thermal transport is dominated by multi-level heat transport. By
taking into account two spin-degenerate energy levels we are able to evaluate
the electronic thermal conductance K and investigate the evolution of the
electronic figure of merit ZT as a function of the quantum dot configuration
and demonstrate ZT ~ 35 at 30 K, corresponding to an electronic effciency at
maximum power close to the Curzon- Ahlborn limit.
