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Do you guys buy the central contention of this article. See below.
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A positive forward was taken when NRG Energy (NYSE: NRG ) announced earlier this week that it began construction on a billion dollar retrofit to its East Texas coal-fired power plant. While the project is being underwritten in part by $167 million from the Department of Energy, NRG Energy sees it being self-liquidating as the carbon dioxide that is captured will be used to yield a 30-fold increase in oil production from an aging oil field NRG Energy also co-owns.

NRG Energy expects this process will improve the production at its West Ranch oilfield from a meager 500 barrels of oil per day to 15,000 barrels of oil per day at its peak. Put another way, at current oil prices that field will go from producing about $18.2 million worth of oil each year to well over half a billion dollars of black gold per year.

While the project is being underwritten in part by $167 million from the Department of Energy...

<Put another way, at current oil prices that field will go from producing about $18.2 million worth of oil each year to well over half a billion dollars of black gold per year.

If the above return is expected, then why was a $167 million grant from DOE necessary in the first place?

Something smells...

Using carbon dioxide for reservoir pressure maintenance/tertiary recovery can be a viable option (being done in Canada, using CO2 from the Great Plains Coal Gassification Plant). First, just using the pop bottle analogy, If you drilled a hole in the cap and sealed a tube in place that reached into the gas above the liquid, shake it a little, and you produce all the foam off the top of the bottle, there is nothing to push the liquids out. If you drilled a hole in the cap and sealed a tube in place that reached into the liquid, then shook the bottle a little, the gas will push the liquid out. If the gas has been produced out of the reservoir, repressurizing it with CO2 can help move oil out--otherwise, it is like trying to suck the coke out of the sealed pop bottle--you'll get some, but no where near the optimum flow.

Another pressure depletion problem can occur when pressures drop to what is known at the 'bubble point' for the reservoir fluids.

The theory: Once a reservoir reaches bubble point (the temperature/pressure where gas bubbles out of the liquids), natural gas can come out of solution in the reservoir, effectively blocking liquid flow through pore throats with bubbles. Pore throats are the paces which connect the pores, often smaller or complex connections.

If the CO2 can be used to restore reservoir pressure, the bubbles can be forced back into solution, the pore throats relieved of obstruction, and remaining liquids recovered--enhanced production of oil, or water, or both.

A lot depends on the variables present in the field, reservoir pressure, rock type, pore geometry, permeability, structural and stratigraphic controls, to name a few.