2 HN users recommended this explainer2 months2020–2025score 2
Years with an HN recommendation, 2007–2026
Linked as a quick, clear primer when black hole energy and efficiency come up.
Minutephysics compares how efficiently different processes convert mass to energy per E=mc^2, from fire and fission to fusion, antimatter and black holes, which can convert a large fraction of mass to energy.
I don’t see why it’s unbelievable. High mass energy conversion is one of the least crazy things about black holes imo. For readers who want some quick info: [this video] This PBS SpaceTime video doesn’t talk about the practical uses of Kugelblitzes, but it isn’t a big leap from understanding what they are to how to get energy out of them. Hawking radiation rate increases as schwarzschild radius decreases. If you could make a properly sized black hole you could convert a little bit of mass into a lot of energy. Maybe this could be harnessed to solve all electricity demand issues. Maybe it could be used to make a room sized bomb that blows up Earth. Vote now on your phones. [link]
Quick info on Kugelblitzes and getting energy from black holes
Well, that very nearly is the method of power generation. It would presumably be paired with some sort of Dyson sphere around the white dwarf. (Remember that a "Dyson sphere" isn't necessarily a solid shell, but just some configuration of matter where no matter which direction the energy goes it is intercepted by something.) You may also enjoy: [this video] which is a minutephysics on black hole power using much the same principles but attaining yet higher efficiencies.
Black hole power using similar principles at higher efficiency
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