Industrial Utility Efficiency    


The advent of manifold-mounted, plug-in pneumatic valves has been a boon for machine builders. It allows them to mount complete valve packages in a safe and secure location on a machine. Using a D-sub connector, serial interface module, or similar single-point wiring system, all of the electrical control outputs can feed into one location on the manifold, greatly simplifying the wiring.
The fundamental question this article poses is, “Are factories happy with vendors of manufacturing equipment (using pneumatic components) dictating their energy footprint requirements?” Compressed air is a significant energy consumer in every plant and to fully understand the ramifications of the imbedded misconceptions with respect to compressed air supply, one must take into consideration the actual point of use needs for compressed air.
Responsible companies are looking at ways to not only reduce their energy consumption, but to make their production more efficient. This is a great general business practice, but how can you be sure that what you are doing has positively impacted the bottom line? More specifically, what can you implement that is repeatable as a best practice to save energy, and better yet, what can you implement that can be used to retrofit various machines across your floor? One solution is found in upgrading to modern pneumatic valves capable of saving energy by reducing compressed air consumption
A plastics molding plant had engaged us to conduct an ‘on-site’ Energy Assessment of their facility. The annual ‘spend’ for electricity, natural gas, and water was about $3.2 million for this modern 275,000 square foot, fully air-conditioned facility. During the Review, several opportunities were identified and delineated in lighting, HVAC, process ventilation, the water systems and energy supply contracts. However, the most significant savings were in their compressed air system.
Machine builders aiming to improve the energy efficiency of their machines tend to focus on using energy media other than pneumatics (typically electro-mechanical or hydraulic) since pneumatics, as traditionally applied, is viewed by some as inefficient due to factors like leakage and over-pressurization (i.e.: supplying a higher pressure in an actuator to accomplish a task which is endemic in practice). But they shouldn't, with its low cost of ownership, pneumatics when properly used remains a viable and many times preferable energy source for a given application. When generating and using compressed air, it's true that there are many places in the system where energy can be lost, however targeted measures within a comprehensive energy saving concept can prevent these losses and significantly reduce energy consumption at the machine level.
Many passenger cars on roads in Germany contain efficiency concepts that make a considerable contribution to lowering emissions. Automotive manufacturers such as VW have gone even further than this, by applying efficiency strategies in their own value added chain. Because the benefits of pneumatics in automotive industry production processes have seen pneumatic actuation win over other drive technologies, efficient use of compressed air plays a key role in increasing energy efficiency.
Why So Many Air Leaks - Even Today?! Energy conservation has been much talked about lately, in the media, the government, and at the water cooler. Lean manufacturing is also a popular topic these days, as are any ways to increase productivity, reduce costs, and increase profitability.  
“We are close to becoming a zero-landfill facility. Zero-waste is the goal,” Mike explained. Company literature on the Green Factory initiative, coordinated in North America by Karen Heyob, Associate Chief Engineer for Honda of America Mfg., Inc. , says the initiative is designed to reduce the impact of Honda’s manufacturing operations on the environment. This includes efforts to reduce the energy intensity of production, as well as initiatives to reduce waste generation, air emissions, and water use at all of the company’s manufacturing facilities in North America.
This West Coast pharmaceutical facility has a very clean and organized compressed air system. All equipments is in good working order in the compressor room. The compressor room itself is very clean and well ventilated. The management requested a compressed air system audit for two reasons:
Compressed air users looking for energy reduction often identify their air compressors as a prime area for savings potential. But …what about end uses? There are a large number of obvious measures that can be implemented, such as leakage reduction, reducing open blowing and eliminating inappropriate uses..however, there are other more technical opportunities available that involve properly specifying or redesigning existing pneumatic circuitry in compressed air operated machines and processes.
Most systems are sized on the supply side at many times more volume and significantly higher pressure than is actually necessary to support the real demand plus a fudge factor generally created out of fear. I am sure that had the OEM defined what is not only minimally necessary in terms of mass flow at density (pressure and temperature), but also with the intent of the highest possible efficiency, we would approach things very differently.