Opportunities to Save On Compressed Air

Since air compressors use a lot of electricity to make compressed air, it is important to use the compressed air as efficiently as possible.  EXAIR has six simple steps to optimize your compressed air system.  (Click HERE to read).  Following these steps will help you to cut your overhead costs and improve your bottom line.  In this blog, I will cover a few tips that can really help you to save compressed air.

To start, what is an air compressor and why does it cost so much in electricity?  There are two types of air compressors, positive displacement and dynamic.  The core components for these air compressors is an electric motor that spins a shaft.  Like with many mechanical devices, there are different efficiencies.  Typically, an air compressor can put out anywhere from 3 SCFM per horsepower to 5 SCFM per horsepower.  (EXAIR settles on 4 SCFM/hp as an average for cost calculations.)  Equation 1 shows you how to calculate the cost to run your air compressor.

Equation 1:

Cost = hp * 0.746 * hours * rate / (motor efficiency)


Cost – US$

hp – horsepower of motor

0.746 – conversion KW/hp

hours – running time

rate – cost for electricity, US$/KWh

motor efficiency – average for an electric motor is 95%.

As an example, a manufacturing plant operates a 100 HP air compressor in their facility.  The cycle time for the air compressor is roughly 60%.  To calculate the hours of running time per year, I used 250 days/year at 16 hours/day.  So operating hours equal 250 * 16 * 0.60 = 2,400 hours per year.  The electrical rate for this facility is $0.08/KWh. With these factors, the annual cost to run the air compressor can be calculated by Equation 1:

Cost = 100hp * 0.746 KW/hp * 2,400hr * $0.08/KWh / 0.95 = $15,077 per year in just electrical costs.

There are two major things that will rob compressed air from your system and cost you much money.  The first is leaks in the distribution system, and the second is inefficient blow-off devices.   To address leaks, EXAIR offers an Ultrasonic Leak Detector.  The Ultrasonic Leak Detector can find hidden leaks to fix. That quiet little hissing sound from the pipe lines is costing your company.

A University did a study to find the percentage of air leaks in a typical manufacturing plant.  For a poorly maintained system, they found on average that 30% of the compressor capacity is lost through air leaks.  Majority of companies do not have a leak preventative program; so, majority of the companies fall under the “poorly maintained system”.  To put a dollar value on it, a leak that you cannot physically hear can cost you as much as $130/year.  That is just for one inaudible leak in hundreds of feet of compressed air lines.  Or if we take the University study, the manufacturing plant above is wasting $15,077 * 30% = $4,523 per year.

The other area to check is air consumption.  A simple place to check is your blow-off stations.  Here we can decide how wasteful they can be.  With values of 4 SCFM/hp and an electrical rate of $0.08/KWh (refence figures above), the cost to make compressed air is $0.25 per 1000 ft3 of air.

One of the worst culprits for inefficient air usage is open pipe blow-offs.  This would also include cheap air guns, drilled holes in pipes, and tubes.  These devices are very inefficient for compressed air usage and can cost you a lot of money.  As a comparison, a 1/8” NPT pipe versus an EXAIR Mini Super Air Nozzle.  (Reference below).  As you can see, by just adding the EXAIR nozzle to the end of one pipe, the company was able to save $1,872 per year.  That is some real savings.

 By following the Six Steps to optimize your compressed air system, you can cut your energy consumption, improve pneumatic efficiencies, and save yourself money.  With the added information above, you can focus on the big contributors of waste.  If you would like to find more opportunities to save compressed air, you can contact an Application Engineer at EXAIR.  We will be happy to help.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Six Steps to Optimization: Step 6 – Control the Air Pressure at the Point of Use to Minimize Air Consumption

Since air compressors use a lot of electricity to make compressed air, it is important to use the compressed air as efficiently as possible.  EXAIR has six simple steps to optimize your compressed air system.  Following these steps will help you to cut your production costs and improve your bottom line.  In this blog, I will cover the sixth step; controlling the air pressure at the point of use.


One of the most common pressure control devices is called the Regulator.  It is designed to reduce the downstream pressure that is supplying your system.  Regulators are commonly used in many types of applications.  You see them attached to propane tanks, gas cylinders, and of course, compressed air lines.  Properly sized, regulators can flow the required amount of gas at a regulated pressure for safety and cost savings.

EXAIR designs and manufactures compressed air products to be safe, effective, and efficient.  By replacing your “old types” of blowing devices with EXAIR products, it will save you much compressed air, which in turn saves you money.  But, why stop there?  You can optimize your compressed air system even more by assessing the air pressure at the point-of-use.  For optimization, using the least amount of air pressure to “do the job” can be very beneficial.

1100 Super Air Nozzles

Why are regulators important for compressed air systems?  Because it gives you the control to set the operating pressure.  For many blow-off applications, people tend to overuse their compressed air.  This can create excessive waste, stress on your air compressor, and steal from other pneumatic processes.  By simply turning down the air pressure, less compressed air is used.  As an example, a model 1100 Super Air Nozzle uses 14 SCFM of compressed air at 80 PSIG (5.5 bar).  If you only need 50 PSIG (3.4 bar) to satisfy the blow-off requirement, then the air flow for the model 1100 drops to 9.5 SCFM.  You are now able to add that 4.5 SCFM back into the compressed air system. And, if you have many blow-off devices, you can see how this can really add up.

In following the Six Steps to optimize your compressed air system, you can reduce your energy consumption, improve pneumatic efficiencies, and save yourself money.  I explained one of the six steps in this blog by controlling the air pressure at the point of use.  Just as a note, reducing the pressure from 100 PSIG (7 bar) to 80 PSIG (5.5 bar) will cut your energy usage by almost 20%.  If you would like to review the details of any of the six steps, you can find them in our EXAIR blogs or contact an Application Engineer at EXAIR.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

How to Size a Receiver Tank and Improve your Compressed Air System

Receiver Tank: Model 9500-60

My colleague, Lee Evans, wrote a blog about calculating the size of primary receiver tanks within a compressed air system.  (You can read it here: Receiver Tank Principle and Calculations).  I would like to expand a bit more about secondary receiver tanks.  They can be strategically placed throughout the plant to improve your compressed air system.  The primary receiver tanks help to protect the supply side when demands are high, and the secondary receiver tanks help systems on the demand side to optimize performance.

Circuit Board

I like to compare the pneumatic system to an electrical system.  The receiver tanks are like capacitors.  They store energy produced by an air compressor like a capacitor stores energy from an electrical source.  If you have ever seen an electrical circuit board, you notice many capacitors with different sizes throughout the circuit board (reference photo above).  The reason is to have a ready source of energy to increase efficiency and speed for the ebbs and flows of electrical signals.  The same can be said for the secondary receiver tanks in a pneumatic system.

To tie this to a compressed air system, if you have an area that requires a high volume of compressed air intermittently, a secondary receiver tank would benefit this system.  There are valves, cylinders, actuators, and pneumatic controls which turn on and off.  And in most situations, very quickly.  To maximize speed and efficiency, it is important to have a ready source of air nearby to supply the necessary amount quickly.

For calculating a minimum volume size for your secondary receiver tank, we can use Equation 1 below.  It is the same as sizing a primary receiver tank, but the scalars are slightly different.  The secondary receivers are located to run a certain machine or area.  The supply line to this tank will typically come from a header pipe that supplies the entire facility.  Generally, it is smaller in diameter; so, we have to look at the air supply that it can feed into the tank.  For example, a 1” NPT Schedule 40 Pipe at 100 PSIG can supply a maximum of 150 SCFM of air flow.  This value is used for Cap below.  C is the largest air demand for the machine or targeted area that will be using the tank.  If the C value is less than the Cap value, then a secondary tank is not needed.  If the Cap is below the C value, then we can calculate the smallest volume that would be needed.  The other value is the minimum tank pressure.  In most cases, a regulator is used to set the air pressure for the machine or area.  If the specification is 80 PSIG, then you would use this value as P2.  P1 is the header pressure that will be coming into the secondary tank.  With this collection of information, you can use Equation 1 to calculate the minimum tank volume.  So, any larger volume would fit the requirement as a secondary receiver tank.

Secondary Receiver tank capacity formula (Equation 1)

V = T * (C – Cap) * (Pa) / (P1-P2)


V – Volume of receiver tank (cubic feet)

T – Time interval (minutes)

C – Air demand for system (cubic feet per minute)

Cap – Supply value of inlet pipe (cubic feet per minute)

Pa – Absolute atmospheric pressure (PSIA)

P1 – Header Pressure (PSIG)

P2 – Regulated Pressure (PSIG)

If you find that your pneumatic devices are lacking in performance because the air pressure seems to drop during operation, you may need to add a secondary receiver to that system.  For any intermittent design, the tank can store that energy like a capacitor to optimize the performance.  EXAIR stocks 60 Gallon tanks, model 9500-60 to add to those specific locations, If you have any questions about using a receiver tank in your application, primary or secondary, you can contact an EXAIR Application Engineer.  We can restore that efficiency and speed back into your application.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb


Photo: Circuit Board courtesy from T_Tide under Pixabay License

6 Steps to Optimizing Your Compressed Air System

If you’re a follower of the EXAIR Blog, you’re probably well aware that compressed air is the most expensive utility in an industrial environment. The average cost to generate 1000 Standard Cubic Feet of compressed air is $0.25. If you’re familiar with how much air you use on a daily basis, you’ll understand just how quickly that adds up.

To make matters worse, many compressed air systems waste significant amounts of compressed air just through leaks. According to the Compressed Air Challenge, a typical plant that has not been well maintained will likely have a leak rate of approximately 20%!! Good luck explaining to your finance department that you’re carelessly wasting 20% of the most expensive utility.


6 Steps from Catalog

The best way to save energy associated with the costs of generating compressed air is pretty straightforward and simple: TURN IT OFF! Placing valves throughout your distribution system allows you to isolate areas of the facility that may not need a supply of compressed air continuously.

Even a well-maintained system is going to have a leakage rate around 10%, it’s darn near impossible to absolutely eliminate ALL leaks. By having a valve that allows you to shut off the compressed air supply to isolated areas, you’re able to cut down on the potential places for leaks to occur.

You’re likely not running each and every machine continuously all day long, if that’s the case why not shut off the air supply to those that aren’t running? When operators go to lunch or take a break, have them turn off the valves to prevent any wasted air. The fact of the matter is that taking this one simple step can truly represent significant savings when done diligently.

You wouldn’t leave your house with all the lights and TV on, so why leave your compressed air system running when it’s not in use? Even if everyone’s left for the day, leaks in the system will cause the compressor to keep running to maintain system pressure.

Taking things one step further, EXAIR’s Electronic Flow Control (EFC) utilizes a solenoid controlled by photoelectric sensor that has the ability to shut off the compressed air when no part is present. If you’re blowing off parts that are traveling along a conveyor with space in between them, there’s no need to continuously blow air in between those parts. The EFC is able to be programmed to truly maximize your compressed air savings. The EFC is available in a wide range of different capacities, with models from 40-350 SCFM available from stock and systems controlling two solenoid valves for larger flowrates available as well.


It’s no different than turning off your house lights when you leave for work each day. Don’t get caught thinking compressed air is inexpensive “because air is free”. The costs to generate compressed air are no joke. Let’s all do our part to reduce energy consumption by shutting off compressed air when it isn’t necessary!

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD