Tag: Compressed Air Savings

Business Benefits of Compressed Air Efficiency

Published on by John BallLeave a comment

A hidden cost that most businesses do not recognize is their compressed air system.  For example, a company has a 75 HP (56KW) air compressor.  They operate two shifts for five days per week.  With an electric cost of $0.10/KWh, the annual electrical cost is around $26,000.   Because of the large amount of energy required to run an air compressor, the pneumatic system is considered the fourth utility.  And saving this commodity and using it as efficiently as you can, should be a priority.  EXAIR has many products to save this energy safely, efficiently and effectively for blow-off and many other applications. 

A recent example; I received an email from an engineer that was looking at our Super Air Nozzles.  They are currently using four blow-off lines that were made from 6mm OD copper tubes.  (Reference picture below). The system was designed to blow out holes after machining.  The engineer was in charge of the task of optimizing 25 machining stations.  He purchased four Nano Super Air Nozzles, model 1110SS, for a trial.  He was impressed with the performance, the low sound level, and the safety design.  But, for upper management, he had to show cost savings in order to change all the stations in the facility.  He asked me to help him with calculating the compressed air savings. 

Blow off station

He gave me some additional details about their application.  He was using the compressed air about 30% of the time throughout two shifts at 8 hours/day at a pressure of 80 PISG (5.5 bar).  He asked to know the savings per day, week, and year, as well as the payback period.  I did many of these calculations for other customers, and I was happy to help.  It is sometimes easier to speak in terms of money for everyone to relate to a situation, especially management.  (The numbers below can be adjusted to match your application and blow-off devices.)

Known:

Cost of compressed air: $0.25/1000 cubic feet of air (this is based on $0.10/Kwhr of electrical cost)

Flow: 1110SS Nano Super Air Nozzle – 8.3 SCFM at 80 PSIG

            6mm OD copper tube – 19.8 SCFM at 80 PSIG

The difference in compressed air flows from a 6mm tube to the Nano Super Air Nozzle is 19.8 SCFM – 8.3 SCFM = 11.5 SCFM.  At a 30% duty cycle, we will get 11.5 SCFM * 0.3 = 3.45 SCFM (cubic feet per minute) of additional compressed air being used.

Per day, the additional amount of compressed air wasted is:

3.45 cubic feet/minute * 60 min/hr * 2 shifts * 8 hr/day (one shift) = 3,312 cubic feet per day.

Per week, the additional amount of compressed air wasted is:

3,312 cubic feet/day * 5 days/week = 16,560 cubic feet per week.

Per year, the additional amount of compressed air wasted is:

4,896 cubic feet/day * 250 days/year = 828,000 cubic feet per year.

With the cost to make compressed air at $0.25/1000 cubic feet, we have the following:

3,312 cubic feet/day * $0.25/1000 cubic feet = $0.83 per day

16,560 cubic feet/week * $0.25/1000 cubic feet = $4.14 per week

828,000 cubic feet/year * $0.25/1000 cubic feet = $207.00 per year.

From these values, the payback for a single, model 1110SS Super Air Nozzle is just under 76 days. 

The remaining life of the Super Air Nozzles will save the company a lot of money by using less compressed air.  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 the yearly figure at $207.00 * 100 = $20,700.00 per year.  The engineer presented these figures to upper management, and it was an easy decision to replace each copper tube with an EXAIR model 1110SS nozzle.  

Don’t be fooled by the upfront cost of tubes or pipes with drilled holes, or other substandard or “homemade” nozzles.  You can see by the facts above that if you use any additional compressed air in your blow-off application beyond that which is necessary, it will cost you in the long run.  If you need help in doing calculations for your applications, EXAIR does have an Air Savings Calculator on our website, or you can contact an Application Engineer directly.  It is like changing your incandescent light bulbs to LED light bulbs for energy savings.  It just makes good business sense. 

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

Photo: Energy saving lamp by Alexas_Fotos.  Pixabay Content License

The Cost of Compressed Air Leaks

Published on by John BallLeave a comment

As margins get tighter and the cost of manufacturing climbs, industries are looking for ways to be more economical.  A big focus is on the compressed air system.  Compressed air is considered to be the “fourth utility” behind gas, water, and electricity.  Air compressors are necessary to run pneumatic systems, but they are the least efficient of the utilities.  For every $1.00 that is put into making compressed air, you only get roughly 5¢ of work from it.  So, it is very important to use this utility as efficiently as possible. 

One of the biggest problems affecting compressed air systems is leaks.  That quiet hissing sound coming from the pipelines is costing your company a lot of money.  A study was conducted by a university to determine the percentage of air leaks in a typical manufacturing plant.  In a poorly maintained system, they found that 30% of the compressor’s capacity is lost through air leaks on average.  Just to let you know, the majority of companies do not have a leak prevention program, so they will fall into the “poorly maintained” category.  To put a dollar value on it, a leak that you cannot physically hear can cost you as much as $130 per year.  That is just for one inaudible leak in hundreds of feet of compressed air lines.  The chart below shows the amount of money that can be wasted by the size of the hole for larger leaks. Unlike a hydraulic system, compressed air is clean, so leaks will not be visible at the source.  You have to find them by other means. 

Most leaks occur where you have threaded fittings, connections, hoses, and pneumatic components like valves, regulators, and drains.  The Optimization products that EXAIR offers are designed to help optimize your compressed air system, and the most effective way is to find and stop leaks.  We have the Ultrasonic Leak Detectors to find inaudible air leaks and the Digital Flowmeters to check your system and find leak rates.  With both products included in a leak prevention program, you will be able to keep your compressed air system running optimally and reduce the cost caused by wasting compressed air. 

EXAIR Ultrasonic Leak Detector: When a leak occurs, it emits an ultrasonic noise caused by turbulence.  These ultrasonic noises can be at a frequency which is inaudible for human hearing.  The EXAIR Ultrasonic Leak Detector, model 9207, can pick up these frequencies and make the leaks audible.  With a signal strength number and bar graph level display, you can find very minute leaks.  It comes with two attachments; the parabola to locate leaks up to 20 feet away, and the tube attachment to define the exact location in the pipeline.  Once you find a leak, it can be marked for fixing.  This simple-to-use instrument can save you a lot of money and headaches. 

EXAIR Digital Flowmeter: With the Digital Flowmeters, you can continuously watch for waste.  Air leaks can occur at any time within any section of your pneumatic system.  You can do regular checks by isolating sections with the Digital Flowmeter and watching for a flow reading.  Another way to monitor your system would be to compare the results over time.  With the Digital Flowmeters, we have a couple of options for recording the air flow data.  We have the USB Datalogger for setting certain time increments to record the air flows.  Once the information is recorded, you can connect the USB to your computer, and with downloadable software, you can view the information and export it into an Excel spreadsheet.  With the digital flowmeters, we also offer wireless capability.  You can have multiple flow meters that can communicate with your computers to continuously log and record the flow information via one gateway.  Once the flow information starts trending upward for the same process, you can use the Ultrasonic Leak Detector to find the leak.  It can also serve as a preventive measure if a pneumatic system is starting to fail.

Leaks in compressed air will cost you in terms of performance, compressor life, and electrical costs.  It is important to have a leak prevention program to check for leaks periodically, as they can happen at any time.  The EXAIR Ultrasonic Leak Detector and the Digital Flowmeters will help you accomplish this and optimize your compressed air system.  If you need more information, you can contact an Application Engineer at EXAIR.  Once you find and fix all your leaks, you can then focus on improving the efficiency of your blow-off devices with EXAIR products.  It will save you even more money. 

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

Photo: Soap bubble and pencils by Carola68.  Pixabay license. 

Basics of Compressors

Published on by John BallLeave a comment
Single Stage Portable Air Compressor

What is an air compressor?  This may seem like a simple question, but it is the heartbeat for most industries.  So, let’s dive into the requirements, myths, and types of air compressors that are commonly used.  Like the name implies, air compressors are designed to compress air.  Unlike liquids, air is a compressible gas, which means that it can be “squished” into a smaller volume by pressure.  With this stored energy, it can do work for pneumatic systems.

There are two main types of air compressors, positive displacement and dynamic.  The core component of most air compressors is an electric motor that spins a shaft.  Positive displacement uses the energy from the motor and the shaft to change volume in an area, like a piston in a reciprocating air compressor or like rotors in a rotary air compressor.  The dynamic types use the energy from the motor and the shaft to create a velocity with an impeller like centrifugal air compressors.  This velocity converts to a rise in pressure.

How do they work?  Most air compressors are driven by an electric or gas motor.  The motor spins a shaft to push a piston, turn a rotor, or spin a vane.  At the beginning of the air compressor, we have the intake where a low pressure is generated from the displacement to bring in the surrounding ambient air.  Once trapped, Boyle’s law states that when the volume decreases, the pressure increases.  For the dynamic type, the velocity and design will increase the air pressure.  The higher pressure will then move to a tank to be stored for pneumatic energy.  The amount of power required is dependent on the amount of air that needs to be compressed. 

Compressed air is a clean utility that is used in many ways, and it is much safer than electrical or hydraulic systems.  But most people think that compressed air is free, and it is most certainly not.  Because of the expense, compressed air is considered to be a fourth utility in manufacturing plants.  For an electrical motor to reduce a volume of air by compressing it, it takes roughly 1 horsepower (746 watts) of power to compress 4 cubic feet (113L) of air every minute to 125 PSI (8.5 bar).  With almost every manufacturing plant in the world utilizing air compressors much larger than 1 horsepower, the amount of energy needed to compress a large volume of air is extraordinary.

Let’s determine the energy cost to operate an air compressor to make compressed air by Equation 1:

Equation 1:

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

where:

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 for two shifts.  So operating hours equal 250 * 16 * 0.60 = 2,400 hours per year.  The electrical rate at this facility is $0.10/KWh.  With these factors, the annual cost for operating the air compressor can be calculated by Equation 1:

Cost = 100hp * 0.746 KW/hp * 2,400hr * $0.10/KWh / 0.95 = $18,846 per year in just electrical costs.

So, what is an air compressor?  The answer is a pneumatic device that converts power (using an electric motor, diesel or gasoline engine, etc.) into potential energy stored as pressurized air.  Efficiency in using compressed air is very important.  EXAIR has been manufacturing Intelligent Compressed Air Products since 1983.  We are able to save you money by reducing the amount of compressed air you use.  If you need alternative ways to save money when you are using your air compressor, an Application Engineer at EXAIR will be happy to help you.  We even have a Cost Savings Calculator to find the annual savings and payback period; and you will be amazed at how much money can be saved. 

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

Photo: Technical Illustration of a portable single-stage air compressor by Brain S. Elliot.  Creative Commons CC BY-SA 4.0

EXAIR’s Calculator Library

Published on by bdwagesLeave a comment

If there is one thing you can always count on it’s a good calculator, and EXAIR offers you 3 — right on our website!!! The calculator library consists of an Air Savings Calculator, an EFC Calculator, and a Cabinet Cooler sizing calculator. All 3 of these add exceptional value and insight into our products. Let’s take a minute and look at each of these calculators in a little more detail.

The Air Saving Calculator allows you to compare a current product, to one of our products based upon overall cost. In order to make this effective for you, you will need to know the SCFM that your current solution is using. With that information, we can factor in the cost of our product and the SCFM consumption of this new solution, and give you an Air and Cost savings number. For example, if you are using a 1/4″ open pipe for blow off, you would be using @ 40 SCFM (not going to mention the OSHA violations – that’s for another blog). By placing one of our Super Air Nozzles on this open pipe, we will save you so much air (SCFM) that you can quickly see (above) that this one nozzle, can save you up to $1350 per year… One Nozzle!!!

The next calculator is the EFC calculator. An EFC is an Electronic Flow Control that can help you quickly automate your process. The EFC will allow you to use air only when it’s necessary and cut down on consumption. For example, if your conveyor has dead space between products, the EFC will shut the air flow off during the dead space. The calculator will tell you how much money you can save by installing the EFC. This will even tell you how long it will take to pay off the initial cost of the EFC unit. To use this calculator you will need the SCFM being consumed, the % of time that the product needs to be on, the purchase price of the EFC (this varies by size, call for details, or see on the link), and your cost of compressed air. We have $0.25 in this blank as a general standard, but if you know your actual, you will get a more concise answer. Your cost could be much higher, I’d be surprised if it is lower. The Example to the left shows the effects of a $1200 EFC that runs a product at 80 SCFM, and needs to be on 45% of the day. The EFC turns off the air the other 55% of the day when there is no reason to run the air. This pays for itself in 76 days, and adds $3960 to the bottom line each and every year.

The 3rd and final calculator that EXAIR offers online is the most used. It is our Cabinet Cooler System Calculator. Electrical cabinets get hot, and will overheat your electronics. Our Cabinet Coolers are the most efficient method to cool these cabinets, and eliminate electronic damage from overheating. There are no moving parts in these Cabinet Coolers, and the Vortex based system cools these with little to no maintenance. You simply need to supply these with clean, dry, compressed air. As you can imagine, these cabinets come in all sizes, and there are all sorts of various electronics that can be inside of these. We need the measurements and temperatures so that we can calculate the correct size Cabinet Cooler system for you. Our Cabinet Coolers have large size differences, from as little as 4 SCFM and 275 Btu/hr, up to 80 SCFM and 5600 Btu/hr, and we can go larger than this if necessary. The good thing about this calculator is that all of the information you need to enter is readily available to you as long as you have a a tape measure and a thermometer.

We do encourage everyone to take advantage of these on-line tools, however always remember that experienced application engineers like me, are here M-F 7AM-4PM EST to help you in any way possible.

Thank you for stopping by,

Brian Wages

Application Engineer

EXAIR Corporation
Visit us on the Web
Follow me on Twitter

Cover photo by Peggy_Marco licensed by Pixabay