Plasma is the fourth state of matter. Heat is required to transfer matter from its one form into another form. So, a plasma cutting makes cut through the electrically conducted material by using hot plasma cutters. It consists of an arc and air blows around that arc.
Production rate must reflect before making an allowance for operating cost because total cost per portion is determined by cost per hour that is compulsory to run the welding machine. The Manufacturing rate is resolute by cutting speed of the machine.
In order to find operating cost power, gasses, labor, daily maintenance cost are calculated. It may take a $10-15 per hour. Laser cost would be higher that is $20 per hour. The water jet is moving expensive above all.
The best quality cut will get from water jet. A water jet produces fine cuts and there is no junk.
Plasma cutter is good but the best precision cut comes from water jet. Water jet does do not involve any heat distortion. Plasma produces heat distortion which can be less by cutting it under water.
So, a plasma cut is not that expensive as that of the water jet.