*Reservoir LIFE Extension Program - part 1Oil and Gas RD&D Programs

One hundred forty years after the discovery of Oil and the birth of the U.S. oil and gas industry, petroleum resources remaining in the ground are still double the amount producers have extracted. Recovering these remaining oil and gas resources poses formidable technical and financial challenges.

Many oil fields are in danger of being abandoned, even though they retain one-half to two-thirds of their original oil. The high capital cost of drilling wells and the difficulty of restoring production leases makes it unlikely that abandoned fields will ever be reopened, even if future oil prices increase significantly. Premature abandonment of wells, in effect, permanently cuts off access to valuable oil assets.

By the year 2015, an estimated one-half of the gas produced in the U.S. is projected to come from low permeability and other unconventional reservoirs. In many reservoirs producing natural gas, previously unrecognized gas-producing zones can be brought into production, thereby extending the life of these gas reservoirs.

DOE, in partnership with the U.S. oil and gas industry, supports the development of innovative and cost-effective technologies that can recover oil and gas from hard to produce resources and extend the productive life of domestic reservoirs. By encouraging advances in oil and gas recovery technologies and facilitating their transfer to producers, DOE can help increase production from U.S. oil and gas resources, help to slow the rate of premature abandonment, and reduce our reliance on energy imports.

Current U.S. oil production is 6.3 million barrels of oil per day. Of this, 37 percent is produced by primary recovery. In mature oil fields, the contribution of primary recovery declines each year, while the contribution of secondary and tertiary recovery increases over time.

Lower-cost, advanced technologies and efficient development strategies, if widely applied by the Nation’s oil and gas producers, are estimated to be capable of increasing the yield of tertiary oil recovery by up to one million barrels of oil per day, and the annual yield of natural gas by up to 6 Tcf per year by the year 2015.

Typically, only about one-third of the oil discovered can be produced economically. Production at most petroleum reservoirs includes three distinct elements: primary, secondary, and tertiary recovery. Tertiary oil recovery is also known as improved oil recovery (IOR), or enhanced oil recovery (EOR).

Primary recovery refers to oil production when energy stored in the reservoir is sufficient to drive the oil through reservoir rock into a wellbore. As reservoir pressure declines with oil production rates, additional oil can be recovered using secondary recovery techniques. One such technology, waterflooding, displaces the oil and drives it to the wellbores of the producing wells.

Oil displacement in the reservoir is incomplete, however, even with secondary recovery processes. Tertiary oil recovery technologies – such as thermal, gas-miscible, chemical, or microbial methods – can provide additional production. Such technologies potentially could lead to substantially higher average recovery efficiency, approaching 50 percent of the “original-oil-in-place” in reservoirs that have “discovered but unrecovered” oil.

Although improved oil recovery technologies have significant potential to extend reservoir life, and have been successfully demonstrated in the laboratory and in the field since the early 1960s, their historically high cost has limited their widespread application. In the last decade, however, dramatic improvements in analytical and assessment tools have led to a greater understanding of reservoir geology and the physical and chemical processes governing multi-phase flow in porous media. This understanding has led to the development of new technologies for reservoir life extension.

*Office of Natural Gas and Petroleum Technology (4.1 - 4.20)