A container equipped with a resistance heater and a mixer is initially filled with 5 kg of saturated water vapor at 105 °C. Now the heater and the mixer are turned on; the steam is compressed; and there is heat loss to the surrounding air. At the end of the process, the temperature and pressure of the system in the container are measured to be 250 °C and 1.2 MPa. Determine the net energy transfer to the steam during this process (in kJ).