Implementing black hole as efficient power plant

TL;DR

This paper models black holes as heat engines, deriving efficiency formulas and demonstrating that a Rankine cycle with back pressure yields higher efficiency, suggesting black holes could serve as energy sources for astrophysical phenomena.

Contribution

It introduces a novel black hole heat engine model using phase structure and Rankine cycles, providing explicit efficiency formulas and highlighting potential astrophysical energy applications.

Findings

Efficiency is charge-independent in the reduced temperature-entropy chart.

Rankine cycle with back pressure mechanism achieves higher efficiency.

Black hole heat engine could be a potential energy source for astrophysical phenomena.

Abstract

Treating the black hole molecules as working substance and considering its phase structure, we study the black hole heat engine by a charged anti-de Sitter black hole. In the reduced temperature-entropy chart, it is found that the work, heat, and efficiency of the engine are free of the black hole charge. Applying the Rankine cycle with or without a back pressure mechanism to the black hole heat engine, the compact formula for the efficiency is obtained. And the heat, work and efficiency are worked out. The result shows that the black hole engine working along the Rankine cycle with a back pressure mechanism has a higher efficiency. This provides a novel and efficient mechanism to produce the useful mechanical work, and such black hole heat engine may act as a possible energy source for the high energy astrophysical phenomena near the black hole.