What is Frozen Fuel?

Frozen fuel is the colloquial nickname given to methane hydrate, which is a form of the natural gas methane trapped inside sheets of ice. Since methane is a valuable energy source, there has been interest in recent years and decades about how best to access these previously undiscovered reserves of energy which are often located at the bottom of the ocean.

However, methane is also an even more dangerous greenhouse gas (GHG) than carbon. As such, it’s vitally important that all possible precautions are taken and all contingencies considered before attempting to mine frozen fuels, since a mass escape of methane into the atmosphere could accelerate global warming dramatically.

How Frozen Fuel is Formed

Normally, methane is formed by a process over thousands of years, whereby the decomposed carcasses of animal and plant life are bacterially broken down and condensed by layers of silt and mud, applying immense amounts of pressure to the fossils. This pressure works with the high temperatures to remove the carbon bonds and thus create natural gas and oil.

However, when this phenomenon occurs at ocean levels depths greater than 500m, the sub-zero temperatures down there can have an interesting effect. Instead of mixing with the water, the methane becomes encased in a shell of ice, thus preserving it indefinitely in much the same way that a recent specimen of moss was discovered to have survived 1,500 years coated in sheets of ice.

Once warmed, the ice melts away and we are left with pure methane.

The Potential Energy of Frozen Fuel

The discovery of these frozen energy sources is a relatively recent one. The first methane hydrate field was located in Siberia in the 1960, while more deposits were found off the coast of Alaska soon after. A flurry of activity in the 90s saw more and more frozen fuel reserves being discovered in places as diverse as Canada and Japan.

Today, the exact amount of total methane hydrate lying latent under our oceans and ice sheets is still not known precisely. However, estimates range from anywhere between a total of 2,800 trillion m³ and 8.5 million trillion m³. If these figures sound too big to be intelligible to you, consider that the current estimated reserves of natural gas in its ‘normal’ form lie around the 368 trillion m³ mark.

Clearly, if even the lowest of estimates prove to be correct, we will have an alternative energy source which will last for well over a century and perhaps much longer. For more information on potential underwater energy sources such as this, check out the article Methane, Ethylene and Ethane in Water.

The Dangers of Frozen Fuel

However, with great potential comes great responsibility. Accessing this precious resource is an ordeal in itself, since mining companies have to first drill at least 500m through the ocean to reach the seabed, before drilling for more than a kilometre more in order to access the methane hydrate deposits. The logistics of this are mind-boggling. Even should scientists and technicians figure out a way to achieve it effectively, much of the methane would still be lost in transportation to the surface.

Here’s where one of the biggest problems lies: once methane escapes, it will find its way into our atmosphere and act as an even more threatening GHG than carbon. This potentially entails speeding up the process of global warming by an alarming margin, which could have catastrophic consequences for lower-lying nations and coastal regions.

Meanwhile, the displacement of the gas from the seabed could also have dire consequences for the ocean floor itself. By removing the frozen fuel, we run the risk of destabilising the seabed and causing huge landslides of silt and other substances, which in turn would certainly cause devastating tsunamis on sea and land.

As such, we must be 100% of the consequences before tampering with this potentially powerful yet devastating substance.