I received an email from an engineer that was looking at our Super Air Nozzles. They currently were using four blow-off lines that were made from 6mm ID copper tubes. (Reference picture) The system was designed to blow out holes after machining. The engineer was in charge of the task of optimizing 25 machining stations similar to this one. He was familiar with EXAIR products from his previous employment, and he recognized the waste of compressed air by using open pipe. He purchased four Nano Super Air Nozzle, model 1110SS, for a trial. He was impressed with the performance, the low sound level, and the engineered design in safety. But, for upper management in his company, he had to show a cost savings in order to change all the stations in the facility. He asked me to help him in calculating the compressed air savings.
He gave me some additional details about their application. He was using the compressed air about 30% of the time throughout an 8 hour day at a pressure of 80 PISG. He wanted to present the savings per day, week, and year as well as the payback period in his evaluation. I have performed many of these calculations for other customers and was happy to help. It is sometimes easier to speak in terms of savings, as everyone can relate to money, especially management. (The numbers below can be adjusted to match your application and blow-off devices).
Knowns:
Cost of compressed air: $0.25/1000 cubic feet of air (this is based on $0.08/Kwh of electrical cost)
Flow: 1110SS Nano Super Air Nozzle – 8.3 SCFM at 80 PSIG
Flow: 6mm ID copper tube – 42 SCFM at 80 PSIG
The difference in compressed air flows from a 6mm tube to the Nano Super Air Nozzle is (42 SCFM – 8.3 SCFM) = 33.7 SCFM. At a 30% duty cycle, we get 33.7 SCFM * 0.3 = 10.2 SCFM (cubic feet/minute) of additional compressed air being used.
Per day, the additional amount of compressed air wasted is:
10.2 cubic feet/minute * 60 min/hr * 8 hr/day (one shift) = 4,896 cubic feet per day.
Per week, the additional amount of compressed air wasted is:
4,896 cubic feet/day * 5 days/week = 24,480 cubic feet per week.
Per year, the additional amount of compressed air wasted is:
4,896 cubic feet/day * 250 days/year = 1,224,000 cubic feet per year.
With the cost to make compressed air at $0.25/1000 cubic feet, we have the following:
4,896 cubic feet/day * $0.25/1000 cubic feet = $1.22 per day
24,480 cubic feet/week * $0.25/1000 cubic feet = $6.12 per week
1,224,000 cubic feet/year * $0.25/1000 cubic feet = $306.00 per year.
From these values, the payback for a model 1110SS Super Air Nozzle is just under 38 days. Because the EXAIR Super Air Nozzles are so efficient, some utility companies will offer a rebate program to use them. This will improve your ROI even more. (We can check to see if your local electric company participates in these programs). Just think, the remaining life of the Super Air Nozzle will be using less compressed air and saving much money for the company.
The calculations above are only for one nozzle. As discussed above with the engineer, they had 4 tubes/station and 25 stations in their plant. So, if you multiply each figure by 100, you can see the large amount of money that can be saved. The engineer presented these figures to upper management, and it was an easy decision to replace all the copper tubes with EXAIR nozzles.
Don’t be fooled by the initial cost of a tube, pipe, drilled holes, or a substandard nozzle. You can see by the facts above, if you use any additional compressed air in your blow-off application, it will cost you a lot of money in the long run. If you need any help in calculating how much money EXAIR products can save you, you can use our Air Savings Calculator from our website, or you contact an Application Engineer at EXAIR. We will be happy to help you.
John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb