synthesised from the conversion of coal or natural gas by the Fischer–Tropsch process, Bergius process, or Karrick process. Currently, two companies SASOL and Shell, have synthetic oil technology proven to work on a commercial scale. Sasol's primary business is based on CTL (coal-to-liquid) and GTL (natural gas-to-liquid) technology, producing US$4.40 billion in revenues (FY2009). Shell has used these processes to recycle waste flare gas (usually burnt off at oil wells and refineries) into usable synthetic oil. However, for CTL there may be insufficient coal reserves to supply global needs for both liquid fuels and electric power generation. Minor sources include thermal depolymerization, as discussed in a 2003 article in Discover magazine, that could be used to manufacture oil indefinitely, out of garbage, sewage, and agricultural waste. The article claimed that the cost of the process was $15 per barrel. A follow-up article in 2006 stated that the cost was actually $80 per barrel, because the feedstock that had previously been considered as hazardous waste now had market value. A 2008 news bulletin published by Los Alamos Laboratory proposed that hydrogen (possibly produced using hot fluid from nuclear reactors to split water into hydrogen and oxygen) in combination with sequestered could be used to produce methanol (CH3OH), which could then be converted into gasoline. Discoveries The peak of world oilfield discoveries occurred in the 1960s at around (Gb)/year. According to the Association for the Study of Peak Oil and Gas (ASPO), the rate of discovery has been falling steadily since. Less than 10 Gb/yr of oil were discovered each year between 2002 and 2007. According to a 2010 Reuters article, the annual rate of discovery of new fields has remained remarkably constant at 15–20 Gb/yr. But despite the fall-off in new field discoveries, and record-high production rates, the reported proved reserves of crude oil remaining in the ground in 2014, which totaled 1,490 billion barrels, not counting Canadian heavy oil sands, were more than quadruple the 1965 proved reserves of 354 billion barrels. A researcher for the U.S. Energy Information Administration has pointed out that after the first wave of discoveries in an area, most oil and natural gas reserve growth comes not from discoveries of new fields, but from extensions and additional gas found within existing fields. A report by the UK Energy Research Centre noted that "discovery" is often used ambiguously, and explained the seeming contradiction between falling discovery