Enhanced oil recovery (EOR) technologies get extra petroleum out of depleted fields by squeezing CO2 into them.

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Five of the seven plants under construction will also use the captured CO2 for enhanced oil recovery (EOR).

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In the fossil fuel industry, both enhanced oil recovery (EOR) and enhanced coal bed methane recovery use compressed CO2 as an input.

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The EOR credit was implemented in 1990, and the Marginal Well Credit was signed into law by President Bill Clinton in 1994.

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"If we can get the technology accelerated by EOR, that's wonderful, " Bjorn-Erik Haugan, CEO of the Norwegian state CCS agency Gassnova, told delegates at the seminar.

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Because an EOR system using atmospheric carbon dioxide removes, rather than emits, carbon dioxide, the fuel it produces would count as very low carbon indeed under California's rules.

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BP's new technique - called LoSal EOR and announced here at the British Science Festival in Aberdeen - promises to increase both the life and yield of oilfields worldwide.

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But among the key barriers to expanded deployments of CO2-based EOR are the lack of economic CO2, the lack of cost-effective method of sequestering and transporting it, and the cost of compressing the gas.

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