Would it be possible to use a black hole to solve our energy crisis indefinitely?

Imagine a power source capable of running indefinitely, with no polluting emissions, using only matter as fuel. A system so efficient it could solve our global energy crisis in one fell swoop.

This idea involves a strange celestial body, a "lunar black hole," as dubbed by Avi Loeb, a professor at Harvard, in his latest publication. This concept could provide almost limitless energy to an advanced civilization.


To understand this innovation, we need to revisit a theory proposed by Roger Penrose in 1971, which suggested extracting energy from black holes via their accretion disk. But Avi Loeb has imagined a different scenario: an artificial black hole weighing 100,000 metric tons (about 110,000 tons) orbiting a planet, much like the Moon orbits Earth.

This small black hole would emit Hawking radiation, which was discovered by physicist Stephen Hawking in 1975. However, such a black hole would naturally evaporate in about a year and a half, unless it were fed 2.2 kilograms (about 5 pounds) of matter per second to sustain it.

If kept fueled in this way, this "black hole engine" would generate a steady power output derived from Hawking radiation, mostly gamma rays, at a rate of 40 quadrillion watts. That's 10,000 times the current global energy consumption. Loeb describes this engine as the most efficient ever envisaged, converting matter into energy with 100% efficiency.

In addition to its power output, this engine could also address the waste problem. Any form of matter, including waste, could be used to fuel this black hole. It's a doubly beneficial solution for any civilization advanced enough to implement it.

Furthermore, this type of black hole could also serve as a "technosignature," which is a detectable sign of an advanced civilization. A rocky planet illuminated by gamma radiation without a visible star nearby could be a sign of such an engine.

Thus, beyond its potential energy promise, this idea of a "lunar black hole" prompts us to rethink our search for signs of extraterrestrial intelligence. Only time will tell if this hypothesis will one day be proven true.