AlJazeeraEnglish on Apr 6, 2011 - It may not seem like it, but used cooking oil could be the world's next hot commodity. PriceWaterhouseCoopers, a London-based accountancy firm, is buying up as much of it as it can, using the oil as fuel to power its offices.
The new headquarters is now one of the most eco-friendly buildings in London. Al Jazeera's Rory Challands reports from the British capital.
