R/P ratio

Figure 1 indicates some gas rich countries, i.e. those that enjoy both large gas reserves and high R/P ratio. Such countries are usually net gas exporters10. In fact, the Asian countries and the Middle East are in the top... 

Figure 1 Gas reserves and R/P ratios as of end 2001 (log scale). Data source BP Statistical Review of World Energy (except R/P for Iraq, which is an estimate).

Table 2 Reserves and R/P ratios of selected countries. Source BP Statistical Review of WorldEnerg 2002Jacee tR/PJorJra whichisanestim e) ...

Reserve/Production (R/P) Ratio 40 years -50 years 100-150 years -65 years... 

As the global consumption of any of the fuels rises, the R/P ratio naturally drops. 

The size of the exploitable proven uranium reserves is a function of the market value of uranium (because as it rises the mining of lower concentration ores became profitable). At 125/kg it is estimated between 4 and 5 million tons. As the present yearly demand for uranium is about 77,000 tons, this reserve is sufficient for about 65 years (R/P ratio = 65). Other estimates suggest that the known reserves will last about 80 to 100 years. On the other hand, if more nuclear power plants are built, the consumption will also rise and therefore the P/R ratio could drop. 

Reserve/production5 (R/P ratio in years) Oil 40 Natural Gas 50 U.S. Coal 1006 70 Unlimited... 

The time when the demand exceeds supply arrives much sooner than the R/P ratio suggests. The R/P values given are based on the rate of use in 2007. As consumption rises because of increased demand in the third world, the R/P ratio numbers are likely to drop further. 

One commonly used indicator of the Nation s gas supply posture is the reserve-to-production (R/P) ratio. The R/P ratio is a measure of the remaining years of proved reserves at the current level of production. Although the R/P ratio does not consider many of the physical limita-... 

SEuropeS Eurasia Middle East Africa Asia Pacific The world s gas reserves-to-produclion (R/P) ratio declined to 66.7 years in 2004, but remains well above Ihe oil R/P latic. Gas reserves are 26% higher than the 1994 levels production is 26% higher. 

While current energy consumption depends primarily on fossil fuels, the world cannot rely on them forever. We eventually will be constrained by resources. Reserve estimates and corresponding reserve-to-production (R P) ratios, defined as the number of years reserves will last at current production levels, are summarized in Table 1.1. 

For oil, the R P ratios indicate that remaining oil reserves are sufficient to last 35-78 years at current production levels. Reserve-to-production ratios are highly misleading for several reasons. First, production levels will increase to meet the projected 45% increase in oil demand projected for 2025 (EIA 2005). Reserve sizes are not fixed. Reserves are resources... 

Understanding our long-term energy needs necessitates a review of reserves and estimates of reserves by fuel type. How long these reserves may last may be considered using a simple measure of reserve size, the reserve-to-production (R P) ratio, or a more complex method, the Hubbert Peak analysis. This analysis assumes production from oil fields basically follows a bell curve, where production increases until the maximum production rate is reached when half the resource has been... 

Two methods commonly are used to assess the adequacy of existing reserves the reserve-to-production ratio and the calculation of the timing of peak production from existing fields, or Hubbert s Peak methodology. The simplest is the R P method. R P ratios for oil reserves are summarized in Table 2.3. At first glance, they suggest oil reserves will last approximately 40 years at current production rates. Of course, as world demand soars, production also will increase, lowering the R P ratio. 

While global R P ratios are in the 40-year range, some countries have an R P of over 100 years, while others have an R P of under 10 years (Figure 2.18). OPEC members have a cumulative R P of approximately 80 years. The rest of the world, excluding the former Soviet Union, has an R P of only 13.6 years. The United States has an R P of only 11.3 years. 

As far as coal is concerned, resource depletion is not an issue. The world s coal reserves will last for generations. At the end of 2002, BP reported global coal reserves of 9.84 x 10 tormes and an R/P ratio of more than 200 years. Almost half the world s reserves are located in OECD countries. The largest accumulations of coal are found in the United States (25 % of global proven reserves), the Russian Federation (15.9%), China (11.6%), India (8.6%) and Australia (8.3 %). The main producers in 2002 were China (29.5 % of global production) and the United States (24%) [3]. 

The reserve-to-production (R/P) ratio denotes a number of years of continued use of fossil fuels when the reserves remaining at the end of any year are divided by the production in that year. From the year 2008 the world R/P amounts to 122 for eoal, 60 for gas and 42 for oil (BP 2009). Therefore, the limit of fossil fuels to serve energy carriers is one side in approaching the transfer from the fossil fuel era... 

---