The advantages of the regualted extraction turbine are that heat suply and power supply can be regulated, the demands of power supply and heat supply can be met at the same time. The contradiction of mutual containment of power supply and heat supply of back-pressure steam turbine is solved. But as for this kind of steam turbine, some of the steam enters the condenser, and part of the heat is lost, and even in an ideal situation, the total heat utilization coefficient is less than 100%. So, total heat utilization coefficient of this kind of heating mode is less than that of the back pressure turbine.