Before 2010, a conventional belief spread by the oil industry was that there was plenty of conventional oil to last the planet for decades. In 2010, the International Energy Agency announced that oil production had already passed its peak. The good news was supposed to be that production of unconventional oil would rise to accommodate energy needs. “Conventional oil” is liquid state oil that occurs naturally and can be extracted and refined with existing technology at market prices. “Unconventional oil” refers to oil derived from tar sands, heavy oil deposits, and oil shale, as well as oil produced through coal-to-liquid or gas-to-liquid technology. Unconventional oil is both hard to extract and expensive.
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