Compressed air cost is driven by more than just compressor efficiency
Did you know the layout of your compressed air system as well as the compressed air ancillaries you add influence your cost bottom line just as much as the air compressor?
When it comes to compressed air, all of us can occasionally have double standards. A compressor is a big investment that most companies make every 7-10 years. Considering the fact that as much as 11% of industrial energy consumption in the UK can be attributed to the production of compressed air, the drive towards more energy efficient equipment is understandable. But an energy efficient compressed air installation needs more than just an energy efficient air compressor.
Commonly overlooked areas in compressed air system efficiency:
up to 0.25 bar
Pressure loss by filters with servicing overdue
between 12 and 20%
Compressed air flow loss when using heatless desiccant dryers
more than £350 annually
Cost of a single air leak as small as 3mm
Did you know, for example, that lowering your compressed air system's operating pressure by only 1 bar would result in overall energy savings of 7 per cent?
The ancillary equipment that comes with your air compressor is more important than you may think. Everyone knows that a broken down compressor usually means a complete halt to production. But a supply of poor quality compressed air can be just as bad, progressively damaging your equipment and threatening the quality of your end product.
For instance, an air compressor installation without a dryer will push moist air through your pipework, resulting in rusted compressed air pipework and tools damaged by moisture and rust particles. Furthermore, over time, the accumulation of rust in your pipework will choke the supply of compressed air to your process, increasing the overall cost of producing the same amount of air that your tools require.
On a tank-mounted compressor, the impact is even bigger, because the moist air collects inside your air receiver and temporarily reduces the amount of air you can store in the first instance. Then, on a more permanent basis, rust begins to form and take away from the available space for storage and can become a safety hazard in your factory. You can read more about why dryers are needed in compressed air installations in this article.
Similarly, neglecting to add appropriate filtration also has an impact. An oil-injected compressor powering a nitrogen generator without the right in-line filters will see to the prompt destruction of nitrogen filtering media, resulting in an expensive replacement, many times more costly than the filters that would have prevented it. And that is just one example.
Designing a good compressed air installation
Understanding ISO 8573-1 classifications (click to enlarge)
A good compressed air installation is designed with the air quality requirements of the production line in mind. Hence, compressed air experts will often ask whether there is an ISO 8573-1 standard specified for the tools that depend on the compressed air supply. A consultant worth their salt will be able to advise on the appropriate standard that a compressed air installation should achieve, even when all they know is the tools that will work with it.
But, as a consumer, it is always wise to be aware of your system's requirements as well as choosing a compressed air partner that is knowledgeable on the subject.
Want to know how to get clean, dry compressed air?
Familiarise yourself with compressed air quality standards:
Compressed air pipework type and layout also plays a major part in the efficiency of your installation
There is much to be said about compressed air leaks, primarily in the cost to your business from retaining and allowing them to grow over time. The image to the right provides a brief overview of the rule of thumb on costs associated with compressed air leaks. An article by Chris Dee, a former executive director of the British Compressed Air Society, looks deeper into the matter of compressed air leaks and the benefits that can come from appropriately fixing them. Similarly, a US-based article featured on Efficient Plant Magazine's website goes into depth on the facts and myths concerning compressed air leaks.
According to the Carbon Trust, a poorly managed compressed air system can lose anywhere between 40% and 50% of generated output to air leaks, even more in certain applications.
Leaks aside, anyone who expects compressed air pipework to be a "clean and cut" matter is in for a big surprise. Much like with compressor types, and compressed air quality standards above, there is more to compressed air pipework than one might imagine. For a start, there are multiple types of pipework that you may choose to use for your installation and it is advised to research your what is best for your business rather than allow an installer to lead the way simply because of their preference.
Another element to bear in mind when it comes to compressed air pipe is planning. An air distribution system expanded haphazardly to keep up with a growing business can cost you money in the long term, in the form of uneven pressure at point of use or a poorer flow.
For an airflow of 30 l/s at 7 bar, 40 hours a week, you also get over 3000 litres of condensate yearly.
Click to check your compressor's output with our calculator!
For an airflow of 30 l/s at 7 bar, 40 hours a week, you also get over 3000 litres of condensate yearly.
Click to check your compressor's output with our calculator!
Manual condensate drains on tank-mounted machines can easily be forgotten about, resulting in condensate water in your process (and products). Invest in timer or electronic drains to safeguard your product quality.
Manual condensate drains on tank-mounted machines can easily be forgotten about, resulting in condensate water in your process (and products). Invest in timer or electronic drains to safeguard your product quality.
Manual condensate drains on tank-mounted machines can easily be forgotten about, resulting in condensate water in your process (and products). Invest in timer or electronic drains to safeguard your product quality.
