Originally Posted by SebC
Sure. Conventional oil is both lighter (meaning more useful, smaller molecules) than Alberta's oil sands and easier to access. With conventional oil, if you want crude oil, you drill a hole in the ground into the reservoir. Typically the reservoir will be at high pressure and push the liquid oil out. There's very little energy requirement to extract the oil, and it doesn't need to be processed to get it to crude.
Contrast that with Alberta's oil. First, you have to get it out of the ground, because unlike conventional oil it doesn't move to the surface by itself. This can be done with mining (least efficient), SAGD (Steam Assisted Gravity Drainage - where you use steam to warm up the oil so it becomes more viscous), thermal methods (burn up a portion of the oil to create pressure and heat), and other experimental methods. The good news here is that economic pressures are pushing the oil companies towards the better methods. The more efficient systems give them higher yields, lower energy overhead, and higher profit margins. SAGD was considered unproven not so long ago, and now everyone's using it. It also creates a much smaller surface footprint than mining. Newer technologies will go even further, and there is progress being made in this area.
Second, Alberta's oil (bitumen) is larger, heavier, longer molecules than conventional oil. It's more like tar than it is like gasoline, which is why the oil sands are also known as the tar sands. For many of our oil companies, the end product they sell is synthetic crude. That means they have to "upgrade" the oil before they sell it. And that means breaking chemical bonds, and breaking chemical bonds requires energy. Even a perfectly efficient plant would take in the energy required to break the bonds.
So my statement is that even with perfect technology, it requires more energy to extract and process Alberta's oil into useful products than it does for conventional oil. I recall one of my profs telling me that this theoretical minimum is around 13% of the energy contained in the oil sands, and this guy has a million-dollar research budget and is one of the leading oil sands gurus. Now, having said that, if we really want to clean up the oil sands, what we should do is use nuclear power to meet those energy requirements. Nuclear is actually one of the cleanest and safest VIABLE energy sources we have. Sadly, the optics for nuclear are bad and so people don't want new plants to be built.
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