Friday, December 14, 2012
Every month I post the numbers for total oil supply, which seems to me the best way to get a sense for the issues around peak oil: how much the global oil supply is actually able to increase or decrease.
However, when you look closely, "oil" turns out to be a slippery concept with the global liquid fuel stream being made up of a variety of things, not all of which are altogether oil-like. The EIA is the agency that keeps the best track of this, so every few months I like to post some graphs based on their breakdown. The components, through August 2012, look as follows:
Here, crude and condensate (C&C: by far the largest part of the stream) are the most truly oil - hydrocarbon liquids that come out of the ground. The other components are NGLs - molecules from ethane to pentane that are condensed out of the natural gas stream and may or may not be liquid depending on circumstances. These are not exactly oil but may substitute for oil in various ways - for example, some butane is added to winter gasoline, propane competes with heating oil as a rural heating fuel, and NGLs and lighter crude fractions are substitutes to some degree as petrochemical feedstocks. So it's not entirely unfair to consider them together with the liquid fuel stream, but nor is it entirely satisfactory.
The "other liquids" are mainly biofuels - ethanol and biodiesel that ultimately come from devoting portions of the world's cropland to fuel production. Meanwhile, refinery gains reflect the fact that some heavier crudes expand during refining (this isn't really an energy gain but is an artifact of our tradition of using volume units for liquid fuels).
This next graph shows the C&C on the right scale and the others on the left scale, making it easier to compare changes (a 2mbd increase will be the same size on the graph for all components):
For a long time, the C&C was essentially flat and one could truthfully argue that all the increase in total liquids was coming from NGLs and biofuels (ie that "real oil" was plateaued or peaking). However, this is no longer true: global C&C production has increased by about 2mbd since the beginning of 2005. Over eight years, this is only a 0.33% average rate of growth - an incredibly slow crawl upward. However, it seems indisputable that it has grown.
We seem to be on a bumpy plateau of global oil production, but that plateau has had a very slight upward tilt.