This week, Chinese engineers collected methane gas from methane hydrate, or “combustible ice”, in the South China Sea and converted it to natural gas in a single, continuous operation . With that achievement, China joined the US, Canada and other nations exploring what could be an abundant source of clean energy. Here’s a closer look at this cool new energy resource. What is combustible ice? In a cold, high-pressure environment such as a deep sea bed, methane produced by microorganisms and water molecules can combine and form methane hydrate, a white solid that can be easily ignited and burns quietly with a blue flame. Some people, therefore, call it combustible ice. Why does it matter to China? Methane hydrate is a very clean source of energy. With one cubic metre of the “ice” equalling more than 160 cubic metres of natural gas, some researchers have estimated the global reserve of methane hydrate is twice as much as that of other known fossil fuels, enough for human consumption for 1,000 years. How was it discovered? Under the China-claimed waters in the South China Sea, mainland scientists found icy deposits with energy content matching 70 billion tons of oil. That was half the country’s total oil and natural gas reserves on land, according to a People’s Daily article on Thursday. Which nations are aggressively exploring its potential? China and Japan are engaging in the world’s most aggressive experiments on methane hydrate exploitation. Both countries have a large industrial sector, depend heavily on energy importation and experience persistent anxiety over oil and natural gas prices. But China has some additional pressures, such as air pollution caused by the over-burning of coal, and the ambition to lead the world as a superpower. How does it fit with China’s new Silk Road strategy? Methane hydrate deposits dot the coastlines of many countries, such as Pakistan, that participate in China’s Belt and Road Initiative, a massive trade and economic integration strategy that is set to redraw the global economic map. Beijing finds fresh ‘fire ice’ reserves in South China Sea China has acquired the technology for “exporting to nations around the Maritime Silk Road, to help solve natural resources and energy problems in the Belt and Road Initiative”, and to “push for economic development and integration”, said the People’s Daily article. How long has China been interested in combustible ice? It could be just propaganda, but government energy survey vessels had been looking for combustible ice deposits since 1995, according to Chinese state media. How hard is it to mine? Test production in the Shenhu seabed showed mainland scientists have created technology that will enable mining the ice in the South China Sea in a sandy seabed, which previously would have posed an engineering challenge to an excavation effort. Could 'fire ice' fuel the future? The test production was carried out by Blue Whale 1, the world’s largest and deepest drilling rig. Built last year, the domestically designed and constructed platform could operate in almost any waters in the world. What is the commercial potential of combustible ice? Though current low energy prices make mining methane hydrate economically unwise at the moment, China is thinking of the future. In a statement on Thursday, the Chinese central government said the breakthrough on combustible ice would trigger a “revolution in energy production and consumption” and help achieve “the great rejuvenation of [the] Chinese nation”.