Wednesday, 28 March 2012

Total's Disaster

Since the abandonment of Total’s Elgin / Franklin platform, it has been hard to get figures on the amount of hydrocarbons coming from the leaking well.  Now they are starting to emerge but differ wildly.  In the Telegraph a figure of 200,000 cubic metres (m3) per day is given for the gas while The Scotsman mentions a value of two kilograms a second (kg/s-1).  According to my basic grasp of sums, this works out to roughly double the first value: 409,000m3 per day.

What does this all mean?  To put it into human values, I checked my gas-supplier’s web site.   

According to Ovo’s figures, the normal winter consumption of gas for a 3-bedroom apartment in winter is 24.48m3 each day.  Even allowing for that on average 3.5% of Elgin’s natural gas is carbon dioxide, on the high figures what is leaking is enough to heat over 16,000 three bedroom flats daily.  Even the lower figure used in The Telegraph is enough to keep a good-sized village warm on a winter’s day.  Bear in mind also that methane is twenty-times a more potent greenhouse gas than carbon dioxide.  

What of the slick?  Better news here.  Owing to the fact that the hydrocarbon reservoir is gas rather than crude oil, the amounts are low: between two and twenty-three tonnes have been cited.  The fluid is gas-condensate rather than oil, so employing the readily available conversion factors for LPG of 11.6 this works out to 267 barrels total so far.   This compares with Deep Water Horizon pumping out 40,000 barrels of oil per day.  However, better no slick than any, no matter how small.

So for this disaster, focus on the gas rather than on how big the sheen on the sea-surface becomes.  Make no mistake, this is a major disaster in the North Sea and, despite the fact there has been no casualties (and I hope that remains the case in the ongoing situation) there ought to be a public enquiry as to what went wrong and whether the current regulation and inspection procedures are sufficient.

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