The filling cost of one 40 liter oxygen cylinder filled to 150 bar with oxygen filling system 04FS:
Filling capacity: 3,2 Nm3/h
Filling capacity/24h: 76.8 Nm3
The volume of oxygen cylinder, type 40L pressurized to 150bar is 6m3, so the per day filling capacity is 12,8 bottles, that makes it 4672 bottles per year.
Power: 5,5 kW
Power consumption to fill one Cylinder is 5.5*6/3.2 = 10.3 kWh, what is at 0.13 EUR for kWh 1.34 EUR.
Maintenance and service cost of the unit: 4670 EUR
Maximum service cost per cylinder is 4670EUR/4672ks = 0.99 EUR
The overall filling cost of one 40L(~6m3) cylinder to 150bar is only 1,34 + 0,99 = 2.33 EUR
It is necessary to add that the overall effectiveness of the whole filling system goes even up with the filling capacity (model).