Although better known for their oil fields, refineries, and petrol stations, BP Plc, Royal Dutch Shell Plc and Total SA are also the world’s biggest oil traders, handling enough crude and refined products every day to meet the consumption of Japan, India, Germany, France, Italy, Spain and the Netherlands. The trio’s sway in commodities trading, largely unknown outside the industry, is set to pay off in 2015 as the bear market allows traders to generate higher returns by storing cheap oil today to sell at higher prices later and using lower prices to make more bets with the same capital.