In New Zealand we have seen the industrial electricity price (c/kWh) rise significantly in the past ten years. The question therefore is - how do we reduce the impact of rising energy costs on our businesses? It is well cited that energy costs account for almost three quarters of the lifetime cost of a compressor. Your compressed air system is therefore a great place to start. Did you realise however that 20% of this cost is attributed to leaks? As the second largest energy cost of a compressed air system, compressed air leaks consequently warrant some attention.
So, what does this energy cost look like in actual dollars? Let’s take the example of a compressor which runs 24/7 and has a power cost of 15 cents/kW/hr. Just one single 2 mm diameter leak could be costing $2,364 per annum! Now imagine the accumulative cost for multiple leaks of similar or even larger sizes…..
But here’s the good news - leak reduction has an overall energy savings potential of 6-10%
The 3 Rs of compressed air leak detection - reveal, repair, repeat
The first step in reducing energy costs created by compressed air leaks is to ‘reveal’ or detect them.
To get started, this may be done in-house by simply listening for hissing sounds or brushing suspected leaks with soapy water. A hissing sound would generally suggest a leak and where a leak has been brushed with soapy water, bubbles would result. However both methods are time consuming and largely inconclusive. In addition, neither method will allow you to identify the volume of these leaks. This is critical in assessing the severity of the leak and therefore the order in which leaks should be repaired.
In contrast, using an ultrasonic leak detector (USLD) would allow you to precisely pinpoint leaks and - depending on the sophistication of the USLD - it can also measure their volume. This hand held non-invasive device, can be effectively used when the plant is in operation, creating no downtime.
Following leak detection, compressed air leaks can then be tagged, prioritised and fixed.
It is important to remember that however advanced or new your compressed air piping may be - leaks will occur. To keep leaks and their associated energy cost to a minimum, leak detection and repair should be continuously on ‘repeat’ i.e. an on-going task. The easiest way to ensure this remains an on-going task may well be to speak to your compressed air service provider about making it a regular part of your compressed air maintenance programme.