German geologists are testing methods of extracting highly flammable methane gas locked up in ice beneath the earth’s surface. Though not ready for commercial use, experts believe this could be a future energy source
This Inupiat Eskimo's backyard might be holding an important future energy source.
As the Earth’s natural resources becoming more and more scarce, scientists are literally going to the ends of the Earth in search of alternative energy sources.
In the permafrost of Canada’s Northwest Territories, German geologists are testing methods of extracting highly flammable methane gas locked up in ice, so-called gas hydrates or "burning" ice, deep beneath the Earth’s surface.
For the first time, the specialists of the GeoForschungsZentrum in Potsdam, succeeded in igniting gas obtained from ice sitting beneath the Earth’s surface. Although the procedure is far from ready for commercial use, experts believe that this could be an important energy source of the future.
"If we were able to release the methane that’s locked into the hydrates here, we’d be in a position to ensure the gas supplies of a large city such as Berlin, for much longer than 50 years," geophysicist Thomas Wiersberg said at the test-site near the Mackenzie river.
How it Works
Facing turbulent icy winds and temperatures of minus 45 degrees, the Germans have devised a controlled process of igniting the methane gas.
The "burning" ice, a mixture of frozen water and combustible methane gas, is locked deep in the sediments. Actually finding the underground deposits poses the first challenge.
To find it, the German scientists set off miniature earthquakes with a so-called seismic spring. After it has been lowered into the ground, the six-meter-long device can set off artificial tremors at the touch of a button.
The spring causes pressure waves to ripple through the permafrost, which are recorded by a receiver in another bore hole. A computer transforms the signals into graphical data.
"We can already see a structure," said geophysicist Klaus Bauer. "These are lovely images from below the ground, but they are still very distorted."
To fill the gaps in the readings, the receiver also records seismic waves, which are turned into audible sounds. Bauer and his men are thus able to find the "beds" containing gas hydrates.
Rise From Beneath
The next step was to find a way to bring the ice-bound gas to the surface. No one no one had ever managed to do that before, until the Germans figured out a way.
They poured hot water through the bore hole, which permeated the permafrost layer and melted the ice which engulfs the flammable gas.
The heat released the methane and it rose to the surface. After three days of trials, the German crews succeeded in extracting methane gas that was so pure it could be set on fire.
Actually, more gas came to the surface than wanted, and had to be burnt off, meaning that reserves are considerably higher than the scientists had originally thought.
Friendly to the Environment
Methane combustion has clear advantages as far as the environment is concerned.
"The fact is, when you take into account the same amount of energy, burning methane releases less CO2 than coal or oil, for example," physicist Wiersberg explained.
In other words, burning the gas from beneath produces less residue and is less wasteful. "The energy balance for methane is simply more favorable," he said.
However, before gas hydrates can be exploited for municipal energy on a commercial scale, the scientists have a good deal of research ahead of them. Nevertheless, these Germans camped out in the Canadian wilderness might just be pointing the way to the energy of the future.