US Energy Department said Wednesday it will invest nearly 5 million U.S. dollars in seven research projects to increase understanding of methane hydrates as a source of energy. The department's National Energy Technology Laboratory will be in charge of the seven nationwide projects from Georgia Tech Research Corporation, The University of Texas at Austin, Texas A&M Engineering Experiment Station, Oregon State University, Massachusetts Institute of Technology, University of Washington and University of Oregon. The research, described as being in the "early stages," will look into the potential for commercialization and the environmental impact of natural gas extraction from hydrate formations. "The recent boom in natural gas production -- in part due to long-term Energy Department investments beginning in the 70's and 80's -- has had a transformative impact on our energy landscape, helping to reduce greenhouse gas emissions and support thousands of American jobs," said Ernest Moniz, U.S. Secretary of Energy. "While our research into methane hydrates is still in its early stages, these investments will increase our understanding of this domestic resource and the potential to safely and sustainably unlock the natural gas held within." Methane hydrate are ice-like structures with natural gas locked inside, which can be found both onshore and offshore, including under the Arctic permafrost and in ocean sediments along nearly every continental shelf in the world. The substance looks remarkably like white ice, but it does not behave like ice. When methane hydrates are "melted" or exposed to pressure and temperature conditions outside those in which the formations are stable, the solid crystalline lattice turns to liquid water, and the enclosed methane molecules are released as gas. As a resource that has massive reserve volume in the earth, methane hydrates are seen as a potential new energy source to replace fossil fuels, prompting many countries to strengthen relative research. The U.S. Geological Survey has estimated that methane hydrates may contain more energy than all of the world's fossil fuels combined. In May 2012, the U.S. and Japan announced a successful field trial of methane hydrates production technologies on Alaska's North Slope. In April 2013, the Japanese government released a draft of five-year basic plan on ocean policy. According to the plan, Japan will develop technology for commercial production of methane gas from methane hydrates starting in 2018. In October, Japan's Minister of Economy, Trade and Industry, Toshimitsu Motegi, asked visiting Secretary Ernest Moniz to strengthen the two countries' cooperation on methane hydrates during a ministerial-level meeting in Tokyo, reported on by local media. However there are still big environmental concerns about this potential resource. Methane is a particularly potent greenhouse gas that is 34 times more powerful in trapping heat than carbon dioxide over a 100-year scale, according to the estimates from Intergovernmental Panel on Climate Change.