Natural gas combustion The hot exhaust gases from the turbine are turns turbine passed through a boiler which generates NATURAL blades GAS WATER中 Turbine E>STEAM turns shaft to generator ELECTRICITY Hot exhaust 少> Exhaust 间 gases Turbine Generator Boiler Figure 3. 13 A small cogeneration plant that uses the combustion of natural gas to drive a gas turbine coupled to an electric generator. The hot exhaust gases boil water to steam for use in space heating Efficiency of a new Overall efficiency coal-fired electric of a cogeneration power plant-38% can reach 70%Figure 3.13 A small cogeneration plant that uses the combustion of natural gas to drive a gas turbine coupled to an electric generator. The hot exhaust gases boil water to steam for use in space heating. Efficiency of a new coal-fired electric power plant – 38% Overall efficiency of a cogeneration can reach 70%