How Much Energy Remains Within the Earth ?

Our planet is still very much an active world.

How long will it be before the Earth essentially ‘dies’ and all active processes grind to a halt ?

Despite having formed over 4.6 billion years ago, the interior of our planet is still blisteringly hot due to two types of energy – primordial energy, which is left over from the Earth’s formation, and nuclear energy, which is essentially the heat being produced by radioactive decay.

This energy is responsible for the active planetary processes that we still see happening to this day such as volcanism and the shifting of the tectonic plates. The Moon, by contrast, is mostly a ‘dead’ world in that it no longer possesses enough energy for these processes to take place.

To learn more about how much more fuel the Earth still has left in its tank, Professor William McDonough and his team at the University of Maryland are aiming to measure the Earth’s geoneutrinos – subatomic particles which are the byproducts of radioactive decay.

“The particles will tell us about how many atoms of uranium and thorium are inside the Earth,” said McDonough. “Therefore, that will tell us about how much radioactivity potential there exists.”

“We know the Earth radiates 46 terawatts of heat, or power, and so what we determine for nuclear energy, the difference would amount to the primordial energy left.”

The project will involve the use of five special detectors situated at key locations around the world however the results of the research are not expected until 2025 at the earliest.

“We’re in a field of guesses,” said McDonough. “At this point in my career, I don’t care if I’m right or wrong. I just want to know the answer.”