The US Department of Energy contracted Cononco-Phillips and Japan Oil, Gas and Metals National Corporation (JOGMEC) conducted a field trial of a methane hydrate production methodology whereby carbon dioxide (CO2) molecules are exchanged in situ for the methane (CH4) molecules within a hydrate structure, releasing the methane for production. So the methane that is released is replaced by CO2. In other words the energy is extracted and the CO2 is pumped back.
The project began in 2008 and the experimental well was started in April and was capped in May-2012. The exchange technology could prove to be a critical tool for unlocking the methane hydrate resource potential in a manner that minimizes adverse environmental impacts such as water production and subsidence, while simultaneously providing a synergistic opportunity to sequester CO2. The well was 830 m deep and produced methane hydrates for 30 days, as was planned.
Globally and for the U.S., methane hydrates represent a potentially huge new source of the cleanest fossil fuel. A recent Minerals Management Service study estimated methane hydrate resources in the Gulf of Mexico at 220,000 trillion cubic feet (TCF), one hundred times the current U.S. proved reserves of natural gas. Hydrate accumulations off the Pacific and Atlantic coasts and on Alaska’s North Slope (ANS) hold additional potential. Yet this potential will remain untapped unless a technically and economically viable means of producing methane from hydrates is found.
Only a fraction of the world’s methane hydrate reserves are potentially recoverable using current technology. Yet the huge size of the resource means that there is, potentially, several hundred years worth of energy available. Methane hydrates promise to provide even more cheap natural gas over a very long time horizon.