A Dyson sphere around a black hole

The whole concept of a Dyson sphere is kinda idiotic. Any civilization that is capable to build one, it is probably able to work out fusion energy very efficiently.

There is no point to go and harness energy around a star or a black hole, when you can just produce it locally with a lot less resources/waste and materials. The sun itself is actually very inefficient in producing energy.

There is no need to harness the sun million of km away, when you can recreate it in your home planet. The only way to produce a dyson like of sphere, is to tame an over-heated sun, and reflect away un-needed energy. But there is no point to build one to just harness it.

It makes great sci-fi stories, but that's about it. Scientifically, it just doesn't make sense.

Why does man use hydro-power even though it is a rather silly idea if he has the technological prowess to generate a lot more power basically at will, basically anywhere, with a lot less resources destroyed, thanks to nuclear energy?

Well, hydro energy is just there, requires comparatively little ongoing maintenance, and has less catastrophic failure modes.

I think the same caveats work for Dyson spheres.

> has less catastrophic failure modes

Given incidence of dam bursts like the 1975 Banqiao dam failure[1], with an estimate death toll of 26,000 to 240,000 people and flooding of over 12,000 square kilometers, I'm inclined to disagree with this assessment.

[1]https://en.wikipedia.org/wiki/1975_Banqiao_Dam_failure

Can you compare number of deaths because of dam failure with number of deaths because of flood and no dam to protect from flood? I.e. should we stop to build dams for flood protection because of telegraph failure at Banqiao dam?