Tiny black holes could theoretically be used as a source of power: study

"Using black holes as rechargeable batteries and nuclear reactors" (2023) https://arxiv.org/abs/2210.10587 :

> Abstract: This paper proposes physical processes to use a Schwarzschild black hole as a rechargeable battery and nuclear reactor. As a rechargeable battery, it can at most transform 25\% of input mass into available electric energy in a controllable and slow way. We study its internal resistance, efficiency of discharging, maximum output power, cycle life and totally available energy. As a nuclear reactor, it realizes an effective nuclear reaction `α particles+black hole→positrions+black hole` and can transform 25\% mass of α-particle into the kinetic energy of positrons. This process amplifies the available kinetic energy of natural decay hundreds of times. Since some tiny sized primordial black holes are suspected to have an appreciable density in dark matters, the result of this paper implies that such black-hole-originated dark matters can be used as reactors to supply energy.

Isn't there a potential for net relative displacement and so thus couldn't (microscopic) black holes be a space drive?

Is there a known inverse transformation for Hawking radiation, and isn't there such radiation from all things?

Don't black holes store a copy of everything, like reflections from water droplets?

PBS Spacetime estimates that there are naturally occurring microscopic black holes every 30 km on Earth. https://news.ycombinator.com/item?id=33483002 https://westurner.github.io/hnlog/#comment-33483002

And ER=EPR: https://twitter.com/westurner/status/964069567290073089

What are the critical conditions for naturally-ocurring and lab or particle-collider made black holes? Are there safety concerns, and how would that be perceived?