  Direct evidence of an inertial-range turbulent energy cascade has been
provided by spacecraft observations in heliospheric plasmas. In the solar wind,
the average value of the derived heating rate near 1 au is $\sim 10^{3}\,
\mathrm{J\,kg^{-1}\,s^{-1}}$, an amount sufficient to account for observed
departures from adiabatic expansion. Parker Solar Probe (PSP), even during its
first solar encounter, offers the first opportunity to compute, in a similar
fashion, a fluid-scale energy decay rate, much closer to the solar corona than
any prior in-situ observations. Using the Politano-Pouquet third-order law and
the von K\'arm\'an decay law, we estimate the fluid-range energy transfer rate
in the inner heliosphere, at heliocentric distance $R$ ranging from
$54\,R_{\odot}$ (0.25 au) to $36\,R_{\odot}$ (0.17 au). The energy transfer
rate obtained near the first perihelion is about 100 times higher than the
average value at 1 au. This dramatic increase in the heating rate is
unprecedented in previous solar wind observations, including those from Helios,
and the values are close to those obtained in the shocked plasma inside the
terrestrial magnetosheath.
