Powerful new microwave drilling technology could help humankind tap into a near limitless source of clean electricity.

Just 0.1 per cent of the planet’s heat content could supply humanity’s total energy needs for 2 million years, according to US company AltaRock Energy.

Yet geothermal only accounts for a tiny sliver of total energy production worldwide.

Current drilling methods struggle to push through the dense rocks, high-pressure, and high-temperature conditions to reach the good stuff deeper down.

The Larderello geothermal field in Tuscany currently produces ~10 per cent of the world’s total geothermal electricity supply.

Since the 1970s engineers have been trying to drill to the magical 3km mark at Larderello; the point where they believe ‘supercritical fluids’ might be found. Supercritical fluids — neither fluids nor gaseous — boast a very powerful energy content.

The latest attempt was halted an excruciating 250m short by the extremely high temperatures.

But a new generation of microwave drilling systems could be tapping into this energy source within the next few years.

AltaRock Energy wants to to “melt and vaporise” rocks with millimetre waves, penetrating rock faster, to greater depths, and at a lower cost than conventional drills do.

The company recently scored a $US3.9m ($5.9m) grant from the US Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-E) to test the tech ahead of drilling real world sites in about 2022.

“Today we have an access problem,” says Carlos Araque, chief exec of Quaise, an affiliate of AltaRock.

“The promise is that, if we could drill 10km to 20km deep, we’d basically have access to an infinite source of energy.”

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