Sunday, June 20, 2010

20,000 Cowboys under the sea

USA imports about 13 million barrels of oil per day, and exports about 2 million barrels per day.

So the cause of the explosion on the rig was a gas bubble that transferred great pressure to the surface equipment. The rig on the surface exploded, April 20th 2010. According to Wikipedia the Deepwater Horizon rig had drilled in deeper waters in the Gulf of Mexico than where it was positioned that day. So the drilling equipment could handle the pressures associated with drilling 10,000 feet below sea level.

The Coast Guard came along to put the fire out. Some people were saying that the Coast Guard should have left the rig alone, in order to let the oil burn off rather than have the oil spread on the surface. This seems like a good idea if you assume that the Blow-out preventer at the sea floor has properly worked.

So why drill there in the first place? 13 million barrels in import and 2 million in export? It seems like the risks of deep off-shore drilling outweigh the benefits. But why is a rig like Deepwater Horizon different to any other rig? The rig that leaked in the Timor Sea is a jack-up rig, it rests on the sea floor on supporting legs. This is possible due to it being positioned in water that is not so deep. Apparently BP are closely watching some legal decisions being made in regards to this incident. The Deepwater Horizon rig was not anchored, but kept in place by motors guided by SatNav. This system is pretty accurate, it can keep the rig positioned over the well to within an accuracy of seven metres, which is pretty straight on top of it when you consider that the riser is 3km under the sea. Blow-out preventers can fail if the pipe that the clamps are trying to squash is leaning over to one side. Was the blow-out preventer hindered from actually working properly because the SatNav system was destroyed, thus allowing the rig to drift and skew the pipe? Don't know. It's unlikely.

'We want to reduce USA's dependence on foreign oil.'
'Also, we're plain running out of places to drill. And we're not allowed to drill much in Alaska.'
'Paying the price of oil coming from Canadian tar sands has made the Deepwater option more attractive. And look at Alberta now: It's like a moonscape!'

Biodiesel isn't the magic answer to all of this. Growing the crops takes up a farmland, and in Indonesia a lot of rain forest is being cut down to make way for Palm oil plantations. Higher prices for beef, anyone? What it does provide is a reasonably priced source of fuel for vital goods transport that might come under jeopardy if OPEC decides to mess with the US dollar and make it very hard for the US economy to keep ticking over enough to pay the pensioners (AND FOR VUVZELAS). That and less chance of a big fuel tanker leaking oil everywhere, like Exxon Valdez in 1989. Biodiesel might get shipped around in large tankers too, but if there ever was a spill it'd have a slightly smaller impact on the environment because biodiesel is more readily biodegradable than crude oil.

The world of fossil fuel production is dirty, immense, and fascinating. The world's safe and easily tapped oilfields have already been found. Technology is getting pushed harder and harder to find more oilfields and bring them online. Compare 'crude oil bursting out of the ground in Texas' to 'sending a pair of robots 1km underwater to try to activate a 400 tonne blow-out valve.'

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