Decommissioning the UK’s offshore oil and gas infrastructure will cost the taxpayer £24 billion, according to estimates from HMRC. So why can’t we leave man-made structures in the sea and thereby save the cost of removal and recycling? That would be a big win for the public purse. However, to do that, we would have to test the pillars of sustainability: the economy, environment and society.
Decommissioning an oil rig is a big job. Offshore installations consist of the equipment for oil and gas processing and drilling (the topsides), and the supporting seabed-to-surface structure. This is most often a steel frame, piled to the seabed (the jacket). The largest steel jacket in UK waters is that of the Magnus oil platform, which weighs 30,000 tonnes – around the weight of 20,000 family cars.