One of the favorite argumentative tools used by people who do not understand oil production limits is R/P ratio. R/P ratio is the supposed magic number that tells how many years of oil we have left. However, in reality it tells us nothing useful about either how many years of oil we have left, what is our production rate or when we should start worrying about oil.

Consider post the very basic primer on reserves and production, which after you have read it, you should feel completely at ease to ignore the whole R/P number and concentrate on data and models that really matter.

What is Reserves to Production supposed to tell us

Reserves to current production rate is a completely theoretical number, which gives a number of years current reserves would last IF we had as much reserves as projected and IF we could produce them at a steady constant production rate (and by implication: IF that constant rate was enough for us).

Three simple facts tell us why this number is completely meaningless and should not be used, unless one is deluded, a bit simple or wants intentionally to mislead:

- Our consumption growth is tied to economic growth and both must grow in the current paradigm that is based on increasing amount of debt. We cannot stay at current level of consumption, it must grow if the economy is to grow (i.e. employment, banks don't go bankrupt, companies keep investing, etc). There goes the ratio. Growth rate would theoretically dictate how long the reserves would last, if we could produce them at an increasing rate. However, we can't produce them at will.

- Our production cannot physically stay at the same current level until we run out of resources. It will drop as time goes by, because geology, technology and resources available make it harder to get each new barrel out. So production will go down.

This *raises* the R/P ratio, but it is completely meaningless. What's the point of having a gazillion dollars in your bank account, if you can draw $1000 today, $950 tomorrow, $900 the day after tomorrow, etc (approaching zero). After 20 days or so you've gone being able to withdraw near zero amount of money out of the bank. End results: you starve with lots of money left in the bank.

This flow of money in this example is roughly similar to how flow of oil happens. Reserves in the ground do not matter at all. Only getting them out at an increasing flow rate (barrels/day) matters and this is physically impossible to accomplish, regardless of money, technology or manpower.

- Reserves are funny numbers. They may be Proven (1P), Proven + Probable (2P), Proven + Probable + Possible (3P) and even Proven + Probable + Possible + Pulled-out-a-hat (4P). With each successive P, you get a smaller likelihood that the reserves actually exist in the real world, instead of being only numbers on a paper conjured up by some obscure mathematical model.

We already know it is very likely that OAPEC resource numbers are of the last variety, i.e. pulled out of the hat and do not really exist. Then there's unconventional oil, which is another completely different type of resource altogether and cannot be simply calculated together with current oil reserves.

So, these three things alone should make it really easy to understand, that R/P means nothing and that it guarantees nothing about business as usual (BAU) continuing for any number of years.

Only ever increasing flow rate at c. 1.8% per annum (minimum) guarantees currently any sort of BAU scenario (with our current consumption model, economy and energy infrastructure). Anything less than that and we are in a worldwide recession (or worse).

Peak oil is about flow rate becoming really hard to increase (e.g. past 3 years) and the time when that flow rate starts to shrink (currently looks very likely to happen within a few years).

That completely destroys any and all BAU scenario for liquid fuels consumption and starts a non-BAU scramble for natural gas and coal demand as well, destroying BAU for those fuels as well.

So, repeat after me:

*I shall never ever use R/P figures again, they are meaningless*

*I shall never ever use R/P figures again, they are meaningless*

*I shall never ever use R/P figures again, they are meaningless*

So, the next time somebody argues about R/P ratios, remember that the number gives us no useful estimate as to how long our oil might last - either altogether or in any meaningful daily quantity. As such, R/P tells us nothing about BAU possibility in the future. To repeat: nothing.

As such, R/P really is a useless yardstick for oil reserve sufficiency and should not be used. If you want a better substitute, look at flow rate models compared against economic growth dictated consumption models, like the one below.