As technology improves the instrumentation of air compressors and auxiliary systems is becoming more modern and useful to assist in improving energy efficiency. A big problem with typical compressed air systems is that it is almost always very difficult to determine how well a given system is performing in terms of efficiency and energy cost. Rarely are there any energy meters monitoring the compressors, nor are there many flow meters. Without these things it is just a guess when you are trying to figure out if your system is running optimally or not.
Wayne Perry of Kaeser Compressors has written an excellent piece on IIoT as it relates to compressed air systems titled “IIoT Comes to Compressed Air”. In the article Perry mentions that compressor control systems have improved and by using the new communication capabilities “gathering, compiling, and analyzing system data on a local level, energy efficiency can continually tracked and monitored”. These are a very valuable tools for plant personnel; with the development of more sophisticated controls and monitoring systems the gathering of this data is becoming less expensive and easier than ever.
In my line of work, part of which involves verifying that compressed air energy efficiency projects actually perform as promised, I value a steady stream of reliable data. I find the data very useful to ensure the expected level of savings has been gained at the end of the project and that the savings are sustained in the long term. I’ve been able to set up a number of remote monitoring systems, connected by cell modem to the internet, that email me key energy performance data on a daily or weekly basis and allow me to download more detailed data to troubleshoot if things go off the rails.
For example, a cabinet making facility upgraded their compressed air system control to optimize the use of their six large compressors. From my desk I can watch instantaneous, daily, or weekly performance indicators. Quite a number of times the data changes substantially and the energy cost per unit output spikes indicating a problem. A few phone calls later we typically find that human intervention or component failure has upset the system, but with a few adjustments things can usually be put back to normal and efficiency is maintained, protecting our investment in the project through energy incentive grant.
At a pork processing plant routine observation of the data has been able to detect air dryer problems that went undetected by operating personnel. After reporting the problem, and successfully resolving the issue, the Plant Superintendent remarked “It seems you know our system better than we do!”. Well yes in terms of energy efficiency he is probably correct.
This shows something important. One common missing element in data collection is finding someone to actually analyze the data, detect problems, then actually doing something about the issues raised. It is so easy to ignore or delete that incoming email or stream of data without actually understanding what it is telling us. Without an easy way to detect problems, and a system in place to initiate action, even the most sophisticated monitoring system is useless.
This week I will be having a heart to heart talk with a Manager of a mine who has been doing lots of ignoring. This system is fully instrumented and is producing daily reports, but has been showing that the mine compressed air leakage flow consumes 70 percent of all the air that is produced. This adds up to six figure financial losses each year, but somehow there is lack of motivation to improve. We will be exploring ways to assist in helping his bottom line, we know the problem, we need to solve it. Attention to data will help, but local action will still be required to gain savings.
Learn more about the benefits of compressed air energy efficiency by attending a Compressed Air Challenge Fundamentals of Compressed Air Systems Seminar. To find the nearest location visit the CAC website. Our calendar of trainings is here.