We present experiments that determine the temperature increase in a type-II
superconductor due to Joule heating induced by vortex motion. The effect o
f Joule heating is detected by comparing the response of the vortex lattice
to fixed amplitude current steps of short (10 mus) and long (4 s) duration
, where the Joule heating is negligible and saturates, respectively. The th
ermometry is based on the temperature dependence of the voltage response of
the vortex lattice to a driving current. By monitoring the temperature inc
rease in NbSe2 samples adhered on a sapphire substrate with GE varnish we o
btain the effective heat transfer coefficient between the sample and the ba
th and show that the heating is primarily due to the power dissipated by th
e vortex motion.