Yes, it is very directional and is made up of 16 folded dipoles arranged 4 by 4 with a mesh reflector. I am not sure of the gain, I was just stating that the effective gain of this antenna over a dipole, which is how quite often ERP is derived in antenna systems such as the one under discussion, is quite a lot. Was trying to be succinct in my response, but no doubt it was not clear enough in stating what ERP is to some. The term is effective, not actual....
Sorry, but you can't make anything from nothing. If the applied power is 500kW then you can't make 20MW without restricting the beamwidth whether it be horizontally or vertically. If you want to cover a vast area of the earth you have to point your antenna up a bit to get the reflections from the ionosphere - if you you to target a specific area then you have to narrow the beam - there's no magic involved. By the looks of their antenna it appears to be like the Russian OTHR with many dipoles against a reflector background - you can't call that 'non-directional.
.View attachment 72783