Unconventional oil

Unconventional oil is petroleum produced or extracted using techniques other than the conventional (oil well) method. Oil industries and governments across the globe are investing in unconventional oil sources due to the increasing scarcity of conventional oil reserves.

According to the International Energy Agency's (IEA) World Energy Outlook 2001 unconventional oil included "oil shales, oil sands-based synthetic crudes and derivative products, (heavy oil, Orimulsion®), coal-based liquid supplies, biomass-based liquid supplies, gas to liquid (GTL) - liquids arising from chemical processing of gas."

In the IEA's World Energy Outlook 2011 report, "[u]nconventional oil include[d] extra-heavy oil, natural bitumen (oil sands), kerogen oil, liquids and gases arising from chemical processing of natural gas (GTL), coal-to-liquids (CTL) and additives."

In their 2013 webpage jointly published with the Organisation for Economic Co-operation and Development (OECD), the IEA observed that as technologies and economies change, definitions for unconventional and conventional oils also change.

Conventional oil is a category that includes crude oil - and natural gas and its condensates. Crude oil production in 2011 stood at approximately 70 million barrels per day. Unconventional oil consists of a wider variety of liquid sources including oil sands, extra heavy oil, gas to liquids and other liquids. In general conventional oil is easier and cheaper to produce than unconventional oil. However, the categories “conventional” and “unconventional” do not remain fixed, and over time, as economic and technological conditions evolve, resources hitherto considered unconventional can migrate into the conventional category.

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