By Graham Hiscott Five of the world’s biggest oil giants are expected to reveal they raked in a £100billion profit bonanza for last year. The bumper haul – equivalent to £3,250 a second – comes as millions in Britain struggle to heat their homes and the planet faces up to the grim realities of climate change. Campaign group Global Witness focused on five of the largest oil and gas producers – BP, Shell, Chevron, ExxonMobil and Totalenergies. The £100bn estimate would be higher if Middle Eastern and Chinese heavyweights were included. Alice Harrison, from Global Witness, said: “The oil giants h…