A method and system for recovery of hydrocarbons from a hydrocarbon-bearing formation. A gaseous component of the produced hydrocarbon-containing fluid is separated from the fluid. The gaseous component is combusted with air in a power plant. Mixing and compressing of the gaseous component and air are realized to produce a flammable and pressurized gas-air mixture prior to combustion. An exhaust gas resulting from combustion is injected into the formation.