Combustible ice as an energy source

The China Geological Survey Bureau announced that China has succeeded in collecting methane hydrate samples from the South China Sea. Methane hydrate looks like ice and is sometimes called "combustible ice." It is a natural gas frozen inside a crystal lattice of water. About 164 cubic meters of natural gas can be released from one cubic meter of methane hydrate, according to one Chinese bureau official. China said it is the 4th nation after the U.S., Japan and India to succeed in the extraction of methane hydrate. (See the U.S. National Methane Hydrates R&D Program.)

While there are vast quantities of methane hydrates in deep waters offshore and under the Arctic tundra, getting to it and making effective use of it, is not without significant environmental risk. Like CO2, methane is a greenhouse gas, but it is 20 times more effective at trapping heat. Release of methane into the Earth's atmosphere could cause further peril from global warming.

For more about this, see Do Hydrates Have a Future?