I've been following a Russian website that publishes their crude oil production on a daily basis. Their oil production is expressed in tons. For all of December so far, it has been in an extremely narrow range of 1341-1349 thousand tons per day. Using 7.33 barrels of oil per ton, that translates to over 9.8 million barrels per day. However, I'm not sure 7.33 is the right conversion factor - there are several different ones on the Internet. Does anyone know anything about this?

NASAguy, I, and I know several others, have been looking for such a web site. Could you please post the link.

Thanks a million,

Ron Patterson

It depends on the gravity of the crude. I don't know what the average number is for Russia. The advantage of using tons is that the weight before and after refining is pretty much the same, whereas the volume (barrels) increases after refining. However, when using barrels you don't have to worry about the API gravity.

In any case, are they talking about C+C or total liquids?

BTW, good article I had forgotten about, with pertinent quotes:

http://www.energybulletin.net/16745.html
Published on 3 Jun 2006 by Energy Bulletin. Archived on 3 Jun 2006.
Confessions of a statistician
by Sohbet Karbuz
(former head of Non-OECD Energy Statistics Section of the International Energy Agency)

. . . Furthermore, it is not correct to make a peak oil analysis based on “all liquids,” because the non-conventional fuels I mentioned above do not come from an oil reservoir . . .

. . . Moreover, customs office and ministry/statistics office may not agree with each other on trade statistics (e.g. Russia). . .

. . . Best data come from EIA petroleum supply monthly but it comes out 2 months after the fact. . . .

. . . Missing link - Conversion Factors: Oil statistics in the world over are expressed by using four most common conventions - litre, cubic metre, barrel, and ton. Since world oil balances are usually expressed in barrels, the selection of appropriate conversion factor is essential. Interestingly, not enough attention is paid how different measurement units for oil are aggregated and which conversion factors are in use.

Although, the relationship between volume and mass measured by density or specific gravity, the number of barrels of crude oil per ton for the same country varies widely, depending on the source. The discrepancies in conversion factors in use, although seem small, are not negligible and in fact already play an important role in world oil balance. This can be demonstrated by using the Russian crude oil production. Russia releases its oil production in tons. Take an original Russian production figure in tons for any year. Then apply EIA and IEA’s conversion factors and see the difference. Do the same exercise for other countries that measure their oil in tons. Sum them up and compare the difference. You will be surprised! . . .

NASAguy thanks a million for the link. Now I can answer Jeffery's question.

In any case, are they talking about C+C or total liquids?

It is total liquids:

Crude Oil&Liquids (000 t)
18/12/07
Lukoil 245.4 0.2
Rosneft 312.7 -0.3
TNK-BP 188.3 0.1
Surgutneftegas 172.3 0.0
Gazprom Neft 88.6 0.3
Yukos 1.2 0.0
Tatneft 68.5 -0.1
Slavneft 55.7 0.0
Gazprom 36.1 -0.1
Bashneft 31.5 0.0
Russneft 39.2 0.6
Total in RF 1349.0 2.1

Ron Patterson

For what it's worth, I interpreted one of your excerpts incorrectly until I read it in context:

For instance, American Petroleum Institute and EIA regularly publish weekly data on the US stock position (with sometimes conflicting with each other). Note that the weekly bulletin of API is based on voluntary reporting with coverage of about 90-95% on most major series. Best data come from EIA petroleum supply monthly but it comes out 2 months after the fact.

The ex-IEA guy isn't saying the EIA data is better than IEA data (which is how I originally interpreted it), but rather appears to be saying that EIA's monthly data is better than EIA or API's weekly data, but comes out much later.

Just a heads-up in case anyone misreads that like I did.

Russia releases its oil production in tons. Take an original Russian production figure in tons for any year. Then apply EIA and IEA’s conversion factors and see the difference. Do the same exercise for other countries that measure their oil in tons. Sum them up and compare the difference.

What are these conversion factors? Might they account for the divergence between EIA and IEA figures?

the conversion from api gravity to specific gravity is:
spg= 141.5/(131.5 + api), a metric tonne is 2204.6 (us)lbs.
and a barrel (42 gallons) of water weights 350.5 lbs. the conversion is bbls/tonne = 6.29/spg or bbls/tonne = 6.29*(131.5 + api)/141.5.

so your conversion of 7.33 bbls/tonne would be correct for an api gravity of 33.4 degrees.

i think you mean tonnes (metric) i.e. 1000 kg