Compressed air is one the most important industrial energy sources. In Germany alone, some 62,000 pneumatic installations are in operation. Not infrequently, however, these installations do not include any monitoring facilities – a serious error, since 79% of the costs of compressed air are accounted for by the electricity used for generation and preparation. Even if compressors, distribution systems and pneumatic actuators are correctly dimensioned, leakage often causes losses of up to 600 l/min. What does it matter, it’s only air, users might think. But even a reduction of compressed-air losses of 100 l/min. saves up to 1000 euros a year.
However, users often fail to exploit this potential for savings due to lack of know-how. Furthermore, in many cases the technical equipment necessary to localise losses is not available. Frequently, lack of time and clarity regarding operational responsibilities prevent the implementation of energy-saving measures. This is precisely where that Festo Energy Saving Services come into play. They can help to monitor and optimise compressed air consumption by simple means. These services always begin with a report thoroughly describing the actual situation and an analysis of the complete pneumatic installation in question in order to identify all the weaknesses, from the compressor through to the applications.
Reducing energy costs
With optimum leak management, costs drivers have no chance of escaping detection. Each leakage point which is eliminated has an immediate effect in reducing compressed-air costs. According to a study by the Fraunhofer Institute ISI (“Compressed Air Systems in the European Union”, 2000), the elimination of leaks alone enables around 42% of total potential savings to be achieved. As part of an efficient leak-management system, a specialist will use an ultrasound detector to check the compressed air system for leaks and will record each leak together with all the associated technical data, such as details of the spare parts required. This documentation will then serve as a master plan for possible savings. This will show all the required maintenance measures and lists the long-term savings against the short-term repair costs.
More and more companies are using precise compressed air consumption data as the main criterion for the choice of new equipment. With a detailed compressed air consumption analysis, they can make savings of up to 50% more than with conventional methods. Even before commissioning, a compressed air consumption analysis can determine the precise compressed air consumption of an installation – both during normal operation and with machines at a standstill. It thus guarantees optimum dimensioning of the compressed air supply system and prevents the possibility of collapse of the supply system due to overload. Particularly important is that a compressed air consumption analysis prevents unnecessary costs, right from the start, which might be caused by an over-dimensioned and therefore too expensive compressed air distribution system.
Optimum compressed air quality ensures a long service life for pneumatic installations and reduces long-term operating costs. Exceeding or not meeting the compressed air quality, with regard, for example, to oil, water or dirt particles, will have a negative effect on the service life of the pneumatic components, resulting in increased energy and operating costs. The compressed air quality analysis offered by Festo Energy Saving Services measures the residual oil content and pressure dewpoint, identifies weaknesses and develops suggestions for improvements, for example filter changes at more frequent intervals. Optimised maintenance can, on average, save 35%.
Ideally, savings measures should begin at the source of the compressed air, the compressors. An energy analysis of compressed air generation – conducted over a period of 24 hours– provides detailed consumption profiles for electricity and compressed air, together with data on pressure levels. Better timing of compressor run times helps optimise their degree of utilisation. Flexible operating scenarios switch compressors off when they are not required and help achieve particularly efficient distribution of power resources. It is thus possible to ensure optimum use of available compressor capacity. Measuring compressed air delivery rate with machines at a standstill provides a mathematical indication of leakage losses and thus possible savings throughout the entire compressed air system.
It is therefore well worthwhile for companies to identify creeping energy losses in compressed air systems by conducting accurate analyses while the systems are in operation. As soon as the results of the analyses are translated into optimisation measures, they can help save valuable energy each and every day. Experts from Festo Energy Saving Services experience this again and again in practice and know exactly where to look for system weaknesses. Thanks to their skilled analyses and suggestions for improvement, companies save money every day.