Ann: Block 9 Alameda 2 Increase in Net Pay, page-438

First of all, it just is, it is a fact. There is no debating that. Even the most cost effective EOR (water/gas) has it's problems, but at least it avoids the following:


source: Narozhnyy, I., Narozhnaya, E., & Ilyenko, A. (2021). Economic Evaluation of Applying the Technology of Water-Gas Stimulation of Formation to Enhance Oil Recovery. IOP Conference Series: Earth and Environmental Science, 720(1), 8

The above is the reason why it costs so much: operating labor-intensive, high-pressure, compressor stations (and the initial up-front capital expenditure).

Secondly, it actually gets worse the more you know about it. For example, there is a chance it doesn't even work at all. EOR can be considered "field specific" meaning, you can pump away all you like, but unless your field can support EOR then it might not even work.

source: Zekri, A., Jerbi, K., & , (2002). Economic Evaluation of Enhanced Oil Recovery. Oil & Gas Science and Technology,


Thirdly, even if you manage to get it to work, there are plenty of cases where it isn't sustainable long term, and is therefore a great risk:


source: Narozhnyy, I., Narozhnaya, E., & Ilyenko, A. (2021). Economic Evaluation of Applying the Technology of Water-Gas Stimulation of Formation to Enhance Oil Recovery. IOP Conference Series: Earth and Environmental Science, 720(1), 8

Fourthly, the hidden problem with EOR is what the recovery rate will be, it can range wildly.

There are almost 10 different types of EOR, it is an exercise in itself to explain why each one costs more, but here is yet another explanation:
"continuous injection of chemicals (e.g., polymer, surfactant, or a miscible solvent) is not an economically feasible option due to the high cost." source:
Perera MSA, Gamage RP, Rathnaweera TD, Ranathunga AS, Koay A, Choi X. A Review of CO2-Enhanced Oil Recovery with a Simulated Sensitivity Analysis. Energies. 2016; 9(7):481. https://doi.org/10.3390/en9070481