2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/125008The basic features of the Poynting flux from the horizon and the ergosphere of a black hole and from the accreting flow onto a black hole are discussed for the force-free magnetosphere. The accretion flow dominated by the Poynting flux is discussed and the possible Poynting flux from the equatorial plane inside the ergosphere is discussed.7 pages, Invited talk at "APCTP Winter School on Black Hole Astrophysics 2006", references added and typos corrected with minor changes in the textAstrophysicstext