Ultimate recoverable resources

The following terms are often used in the context of quantifying reserves and resources of fossil fuels the Estimated Ultimate Recovery (EUR), also called Ultimate Recoverable Resources (URR), is the sum of past cumulative production, proved reserves at the time of estimation and the possibly recoverable fraction of undiscovered resources. The remaining potential, i.e., the sum of reserves and resources, is the total amount of an energy source that is still to be recovered. The mid-depletion point is the point of time when approximately 50% of the EUR (at field, country or world level) has been produced. 

Different estimates of the ultimately recoverable resources lead to different time windows for the mid-depletion point of oil. Estimates of the EUR at country level can differ, for instance, because of different boundaries between conventional and unconventional occurrences, and depend on assumptions about recovery factors,... 

The projected growth scenarios for conventional gas seem justified from the point of view of ultimately recoverable resources, and unlike for oil, no major discrepancies between projected demand and supply are to be expected in the coming decades. An important aspect of the future availability of natural gas, however, is the creation of the necessary infrastructure for the production and subsequent transport of the gas to the customer. The cumulative investments for the gas-supply infrastructure until 2030 are estimated to amount to US 3.9 trillion (IEA, 2006). 

FIGURE F-2 Annual production scenarios for the mean resource estimate showing sharp and rounded peaks, 1900-2125. Growth rate leading to either peak is 2 percent. Sharp peak occurs in 2037 followed by decline at reserve to production ratio of 10. Rounded peak occurs in 2030 followed by decline at 5 percent. U.S. volumes were added to the USGS (2000) foreign volumes estimate to obtain a world total of 3,000 billion barrels (mean value) of ultimately recoverable resources. SOURCE EIA (2000). 

As annual NaNOs shipments topped 1 million tonnes concerns arose about the long-term availabiHty of the resource. But, as is common with ultimately recoverable resource estimates, a widely publicized 1903 forecast—which concluded that at the rate the Chilean nitrates had been mined between 1840 and 1903 their deposits would be exhausted by the year 1938—was too conservative. In 1908 Alejandro Bertrand put the nitrate resources of the Tarapaca and Antofagasta regions at about 220 Mt, and a later detailed appraisal put the country s total probable resources at 920 Mt. If completely exploited, this resource would have been enough to support an annual output of 2.7 Mt, the rate reached just before the beginning of World War I, for 340 years—but those 920 Mt of NaNOj contain less nitrogen than is now fixed in just two years by the synthesis of ammonia ... 

Resource estimates and current production According to the USGS, total resources of extra-heavy oil in place worldwide are estimated at around 1350 Gb, of which about 90% are located in the Orinoco Belt in Venezuela. It is estimated that between 240 and 270 Gb of the Venezuelan resources in place are ultimately recoverable. The synthetic crude produced from heavy oil is considered to be refined oil and is, therefore, not subject to OPEC quotas, unlike Venezuela s conventional oil production. 

A final term used to define total oil reserves is estimated ultimately recoverable (EUR) reserves, which includes cumulative production to date, current reserve estimates, and those reserves that remain to be found and exploited. In Figure 2.11, the EUR would make up a portion of the resource base plus cumulative production to date. 

An important aspect of lead is that it is a recoverable resource. It has been estimated that more than 95% of the batteries sold in the United States are ultimately recycled, and it takes considerably less energy to recycle lead, a low-melting metal (mp 327.4°C), than to produce the metals used in other storage battery systems (nickel, iron, zinc, silver, and cadmium) in battery-grade quality. 

Estimated ultimate recovery ( UK) is not a resource category as such, but a term which may be applied to an individual accumulation of any status or maturity (discovered or undiscovered). Estimated ultimate recovery is defined as those quantities of petroleum which are estimated, on a given date, to be potentially recoverable from an accumulation, plus those quantities already produced from there. 

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