Air Leak Savings AnalysisAir Leak Savings Analysis
ERS Ultrasonic Leak Detection Survey
Results Summary
Facility: ____________ Corp.Survey Date: April 1, 2001
Leak Repair Cost Summary Annual Demand and Energy SavingsNumber of leaks detected and tagged: 176 Peak AnnualEstimated CFM attributed to repairable leaks: 450.2 kW kWh
Total Existing Usage: 538.9 3,052,863Estimated Leak Repair Cost (at $100 per tagged leak): $17,600 Total Proposed Usage: 423.5 2,399,874
Case Study Case Study Air Leak ResolutionAir Leak Resolution
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$14,960 652,989 115.4 $53,429
Simple Payback (years): 0.3
ERS performed a compressed air survey using ultrasonic leak detection equipment and tagged one hundred seventy six (176) compressed air leaks throughout the facility. The majority of these leaks were located at connection points of fittings, filters, lubricators, regulators, control valves, and hand blow-off guns.
Most of the leaks were easily repaired. Leaks at threaded connections were repaired by simply backing off the fitting, applying thread sealant, and reassembling. Where parts had failed, such as hoses and filter bowls, new replacement parts were installed.
We estimate the diversity of compressor loading and, utilizing a performance curve for the size and type of compressor involved, predict energy losses due to the leaks observed.
Case StudyCase StudyEfficient Air NozzlesEfficient Air Nozzles
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$5,180 79,698 10.3 $5,482
Simple Payback (years): 0.9
Blow-off and part positioning on selected equipment is achieved with a steady stream of high velocity compressed air. The compressed air is delivered through copper tubing focused on the desired locations. These machines currently use 1/16” copper tubing to deliver air streams at 95-100 psi for part positioning and feeding. At 100 psi, such an orifice will deliver just under 6.5 CFM.
Installation of efficient air nozzles was recommended to meet the process requirements but with significantly reduced compressed air consumption. An efficient air nozzle at similar pressure will consume only 4.5 CFM of compressed air. These nozzles are designed to significantly reduce compressed air consumption, thereby reducing compressor runtime.
Case StudyCase StudyInstall Air Solenoid ValvesInstall Air Solenoid Valves
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$3,650 121,499 na $8,357
Simple Payback (years): 0.4
There is a wide array of distributed equipment in the facility that requires compressed air. During non-producing periods, some of this point-of-use equipment continues to consume air and waste energy. Air loss at the equipment during non-producing times can be curtailed by controlling the supply to the equipment.
Compressed air supply should be controlled by installing solenoid valves that are electrically interlocked with machine operation.With such an installation, compressed air can be supplied to the equipment only when it is required for operation, eliminating waste during machine downtimes.
Case StudyCase StudyFlow Controller/Reduce PressureFlow Controller/Reduce Pressure
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$40,600 72,724 60.6 $9,850
Simple Payback (years): 4.1
The existing compressed air system pressure setpoint of 105 psi is currently required to meet the facility demand. This pressure setting is necessary to account for pressure band fluctuations typical to compressed air systems with large demand, inadequate storage and no precise flow controlling equipment. Pressure swings of 10 psi are common. Subsequently, system pressures are set artificially high to ensure demand requirements at the point of use equipment.
Installing a flow controller and storage capacity will solve this problem and save energy. Flow controllers with sophisticated sensing and flow response capabilities allow for delivery of pressures within a two psi band. This narrow band allows demand side delivery pressures to be reduced considerably, lowering overall compressed air consumption and reducing compressor run times.
Case StudyCase StudyInstall Sequencing ControlInstall Sequencing Control
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$43,405 657,842 na $45,246
Simple Payback (years): 1.0
The facility’s compressor plant is composed of multiple rotary screw compressors operating continuously in modulation mode. Each compressor operates on local controls; no central sequencing controls exist. Installing a master sequencing control system to network the compressors together will allow for dynamic optimization of the system as a function of demand. Networking multiple compressors with a microprocessor based sequencing controller facilitates system optimization by minimizing compressor horsepower to meet the load.
The controller dynamically monitors system demand and continually adjusts the compressors’ operating sequence. The controller will select horsepower in a programmable manner to best match available compressor capacity, minimizing compressor part-load operation and maximizing system efficiency. By establishing a base/trim profile, all compressors on line are operated fully loaded before the next compressor is brought online in the system.
Case StudyCase StudyInstall Blowers for BlowInstall Blowers for Blow--Off OperationsOff Operations
Total Cost
$
Energy Savings
kWh
Demand Savings
kW
Annual Savings
$
$79,278 683,940 220.9 $64,846
Simple Payback (years): 1.2
On several extrusion lines, compressed air is currently used for blow-off drying as the product exits the cooling tanks. Additionally, blow-off is used as the product exits flocking stations to remove excess flock. The same function can be provided at a much lower operating cost with centrifugal blower systems.
Installation of three centralized blower and air knife/nozzle systems to supply blow-off air to the extrusion lines will result in lower operating costs. Blower systems that deliver high volumes of lower pressure air directed with air knife and nozzle systems are effective and economical compared to compressed air.
