In the year 2138, a law requires certain limits on the production of entropy of any marketable piece of technology. This law is similar in nature to the old air pollution laws of the 20th century. It sets an upper limit of 1.00 × 10-3 kJ/(kg · K · s) on the entropy production rate density of any new technology.
This becomes known simply as the EPRD number, determined by dividing the entire mass of the system generating the entropy into its total entropy production rate.
Determine the steady state EPRD of an insulated steam turbine that has a total mass of 2000. kg, takes in steam at 3.50 MPa, 400.°C at a rate of 2.00 kg/s and exhausts it at 5.00 kPa, 90.0% quality.