Could quasars be generating energy from fusion? I mean with all that material falling on it...
Energy cannot be generated, only transformed. The density is too low to produce relevant fusion power - you always have a few atoms fusing, but that does not have any effect. The accretion disk releases much more energy than even a 100% fusion rate could do.
That "it" is presumably is black hole, which has no solid surface on which matter might fuse, unlike a white dwarf or neutron star
The sun doesn't have a solid surface either. Black holes have accretion disks (that's where the radiation comes from).
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