Deep Heat.

The article focuses on how the tapping of residual heat at the Earth's core could yield a renewable source for energy production than what is currently produced by all the hydrocarbon resources around the world. Cited are geothermal energy for power production that currently exists in parts of the world, drilling challenges that cause oil and gas companies to show little interest in geothermal technologies, and the plan of Fervo Energy to use fibreoptic cables to monitor geothermal wells.