Compressed air is one of the most expensive uses of energy in a manufacturing plant, accounting for $1.5 billion per year in energy costs in the United States. Optimization of compressed air systems can provide energy efficiency improvements of 20 to 50 percent!
CPT will assess your compressed air system, calculate your cost of compressed air and recommend improvements for energy efficiency.
To understand the basic capabilities of the system and its various modes of operation, CPT will analyze the supply side of your compressed air system for the types of compressors used and the type, suitability and settings of capacity controls and other operating conditions.
CPT will verify that air compressors are not too big—oversized—for end uses. For example, an air compressor is oversized if the end use only requires air pressure that is 50 percent of the pressure that the compressor is capable of producing. If your compressor is oversized CPT may recommend adding a smaller compressor and sequence-controls to make its operation more efficient when partially loaded. Sequence-controls can regulate a number of compressors to match compressed air needs as they vary throughout the day.
CPT will check your compressed air system for leaks. A distribution system under 100 pounds-per-square-inch gauged (psig) of pressure, running 40 hours per week, with the equivalent of a quarter-inch diameter leak will lose compressed air at a rate of over 100 cfm—costing over $2,800 per year.
The compressor must produce air at a pressure high enough to overcome pressure losses in the supply system and still meet the minimum operating pressure of the end use equipment. Pressure loss in a properly designed system will be less than 10 percent of the compressor’s discharge pressure. If pressure loss is greater than 10 percent, CPT will evaluate your distribution system and identify areas causing excessive pressure drops. Every two pounds-per-square-inch decrease in compressor pressure will reduce your operating costs 1.5 percent.
Artificial demand is created when an end use is supplied air pressure higher than required for the application. If an application requires 50 psi but is supplied 90 psi, excess compressed air is used. CPT can install pressure regulators at the end use to minimize artificial demand.
Air Receiver/Surge Tank Sizing
If your compressed air system does not have an air receiver tank, CPT may recommend adding one to buffer short-term demand changes and reduce on/off cycling of the compressor. CPT will size the tank to the power of the compressor. For example, a 50 hp air compressor needs approximately a 50-gallon air receiver tank.