The following is a cut and paste from a Sept. 16, 2012 article by Kurt Cobb in The Christian Science Monitor, plus some comments of my own..
Tar sands, for example, are a mixture of sand and bitumen, a thick, gooey hydrocarbon that is often used to make asphalt. The bitumen is separated from the sand using hot water. Essentially, the bitumen moves to the top and is skimmed off. This is obviously water-intensive; but it is also energy-intensive since the sands must first be mined and transported to a separation facility. Then, enormous separators filled with water heated using natural gas start the separation process. That process is repeated to get up to 90 percent of the bitumen out of the sand.
But we don't yet have oil. The bitumen must be put through another energy-intensive "upgrading" process that typically strips the hydrogen off natural gas molecules and makes them available to the bitumen under great pressure and heat using the proper catalysts. Finally, the sulfur must be removed. Then, and only then, do you get something that resembles what we call oil. In fact, it is referred to as syncrude--short for synthetic crude--because it is not naturally occurring and must be manufactured.
As you might intuit, ramping up tar sands production has been easier said than done. Energy writer Chris Nelder noted the gap between projected and actual production: "Let's remember that tar sands production was projected to grow from 1 mbpd [million barrels per day] in 2006 to 2.8 mbpd in 2012, but actual production is currently just 1.6 mbpd," he wrote citing a Canadian Association of Petroleum Producers forecast from 2006. Promises of 5 mbpd by 2030 ought to be taken with a grain of salt. And, 5 mbpd needs to be put in the context of a world that according to the U.S. Energy Information Administration (EIA) is projected in 2030 to consume 108 mbpd of so-called "total liquids" (which include not only oil, but bio fuels and natural gas plant liquids such propane and butane.) I have my doubts that we will reach either 5 mbpd from tar sands production or 108 mbpd in worldwide production of liquid fuels given the difficulties of producing unconventional oil.
Cobb makes the point, correctly I think, that reserves are not the important issue, but rather what is important is the flow rate. With tar sands they have a very low recovery rate. In addition, it takes about 1 gallon of oil BTU's to extra about 3 gallons of oil. A lot of the underground tar sand has a much lower recovery rate than surface tar sands. Hence, it is unlikely that the flow rate from tar sands will ever be a "game changer" within the scope of things. There is a ton of energy related information in the press that is factually incorrect.
The best example of bad information is when articles say there is 3 trillion barrels of oil equivalents in the western oil shale. If it were true (which is not) that there was 3 trillion barrels of liquid oil that could be extracted, that would be a game changer. That might last 50 to 100 years. To imply though that there is this kind of energy that can be recovered from oil shale is ridiculous. To date there have been ZERO barrels of oil extracted commercially from oil shale. There are a hand full of test projects, where large companies are trying to figure out was to extract some of this energy. Additionally, this formation yields kerosene, propane, butane, etc, but no gasoline.
If the U.S. doesn't get started on transitioning away from liquid oil to alternatives (natural gas and electric), something is going to happen to disrupt the liquid oil flow, and BANG the economy crashes.
It is ulikely that the flow rate from tar sands will ever amount to much.
Remember, it is what comes out of the faucet that runs the economy. Reserves can be easily manipulated. OPEC does this in mass, probably reporting reserves that are double what they report to the IEA, EIA, and BP. It's what comes out of the faucet, not the size of the tank.
Right now there is a serious question as to whether the world can ever increase the flow much from the current level. It that is the case, our exponential population growth, debt growth, and economic growth can no longer grow like it has in the past. I suspect that energy is the real reason world growth is slowly slowing down. At best, all we can do is shift the curve 5 or tens years before we run low on liquid oil and perhaps other energy things as well.
This is why caol is going to rise again. It has to, because the world needs the coal BTU's, no matter how dirty. Somebody in the world will burn it.