  In this work, we investigate the electromagnetic energy released by
astrophysical black holes within the Kerr-Taub-NUT solution, which describes
rotating black holes with a nonvanishing gravitomagnetic charge. In our study,
we consider the black holes in the X-ray binary systems GRS 1915+105, GRO
J1655-40, XTE J1550-564, A0620-00, H1743-322, and GRS 1124-683. We show that
the Kerr-Taub-NUT spacetime can explain the radiative efficiency of these
sources inferred from the continuum fitting method (CFM). We also show that, in
the framework of the Blandford-Znajeck mechanism, it is possible to reproduce
the observed jet power. We unify the results of the two analyses for the
selected objects to get more stringent constraints on the spacetime parameters.
We show that, as in the case of the Kerr spacetime, the Kerr-Taub-NUT solution
cannot simultaneously explain the observed jet power and radiative efficiency
of GRS 1915+105.
