  I Zwicky 1 is the prototype optical narrow line Seyfert 1 galaxy. It is also
a nearby ($z=0.0611$), luminous QSO, accreting close to the Eddington limit.
XMM-Newton observations of I Zw 1 in 2015 reveal the presence of a broad and
blueshifted P-Cygni iron K profile, as observed through a blue-shifted
absorption trough at 9 keV and a broad excess of emission at 7 keV in the X-ray
spectra. The profile can be well fitted with a wide angle accretion disk wind,
with an outflow velocity of at least $-0.25c$. In this respect, I Zw 1 may be
an analogous to the prototype fast wind detected in the QSO, PDS 456, while its
overall mass outflow rate is scaled down by a factor $\times50$ due to its
lower black hole mass. The mechanical power of the fast wind in I Zw 1 is
constrained to within $5-15$% of Eddington, while its momentum rate is of the
order unity. Upper-limits placed on the energetics of any molecular outflow,
from its CO profile measured by IRAM, appear to rule out the presence of a
powerful, large scale, energy conserving wind in this AGN. We consider whether
I Zw 1 may be similar to a number of other AGN, such as PDS 456, where the
large scale galactic outflow is much weaker than what is anticipated from
models of energy conserving feedback.
