Compressed Air System Optimization Rebate 11/1/2010
Huge Potential for Savings In many plants, compressors use more energy than any other type of equipment Many plants can realize energy savings of 20 to 50% while improving system performance Sources of waste: Leaks Pressure drop Artificial demand Inefficient controls Inefficient compressors In every facility we visit, there’s always room for improvement. In many locations, compressors use more energy than any other type of equipment. Savings from 20-50% can be gained by making some improvements. Get rid of the leaks, pressure drops, artificial demand, etc.
Methods of Increasing Energy Efficiency Here’s a chart showing the different methods energy efficiency can be increased: The motors can be upgraded to a high efficient drives system. We’ll save 2% there. What type of control are you using on your compressor? Remember earlier today, we showed how when the unit is not compressing any air, that we are using 70% of energy. For what? We’re not doing anything and still using 70%. Heat recovery could be a big savings also. We’ll look at it a little later, but as we all know when we compress air, heat is a by product produced. Since you already have the heat there, why not use it? Maintenance the compressor and clean air treatment equipment regularly. How many times have you heard “I paid $300 for that filter, so I’m going to get the most out of it. When a large pressure drop happens, remember, our compressor has to work harder. If it works harder, we are using more energy. Of course minimizing leakage is a big one and we’ve talked about it all day. Cumulative potential savings 35.7% *article from the VDMA Nachrichten
ZERO Loss Condensate Drain
Automatic Magnetic Drain (AMD) Kaeser’s AMD line of automatic drain traps is the premiere drain in the industry. The AMD 6550 is a rugged demand drain (does not waste compressed air) designed for use at moisture separators and wet receiver tanks. These are typically the largest moisture producers and dirtiest locations in the compressed air system. The AMD 1550 is Kaeser’s latest addition to the AMD family. It is a smaller, lower cost drain designed for use at filters, dryers and moisture separators. AMD 6550 AMD 1550
AMD 6550 Drain Operation Automatic Magnetic Drain Traps Opposing magnets Working cylinder The drain trap itself is simple: As liquid condensate begins to fill the bowl, the stainless steel float begins to rise. Once the liquid rises to the maximum level, two opposing magnets switch open a valve which allows air pressure to a working cylinder. The working cylinder simply opens a self-cleaning, 3/8” ball valve, which allows the condensate to drain from the bowl. As the liquid level in the bowl drops to the minimum level, the opposing magnets switch the air valve closed, and a return spring in the working cylinder forces the ball valve closed again. 3/8” ball valve
Eco-Drain Series Eco-Drain 14 Eco-Drain 13 Eco-Drain 12 Eco-Drain 30
Eco-Drain Series Drain Traps Eco-Drain Operation
Master Controller
Upper Range Modulation Part Load Energy Consumption % of Full Load Input kW Required Energy Savings Frequency Control On Line – Off Line Turn Valve Upper Range Modulation Turn Valve with Vented Sump % of Full Load Capacity 20 40 60 80 100 Straight Modulation If you want to see how much a compressor costs running, its very easy to figure out. Take the overall power consumption (kW) by how often it runs and how much you’re charged per kW/hr. This gives you the magic number. Lets take a look at some examples.
Sample 1 – SFC 110, 2x CSD 75 and SAM
Sample 1 – Sample Day CSD 75T base loaded the entire day. SFC 110 trims as necessary maintaining +/- 1 psi within the system. Averaged over 10 seconds.
Sample 1 – SAC Plus February 2008 Sample Week Energy Cost Table (SAM Controlling System) Flow Profile of Sample Week 2162859 Duty cycle of all three units almost 100%, which results in the lowest possible Idle Power Cost. A sample week of ADA Group 1 data was downloaded from the SAM for February 2009. A cumulative flow (top left) and a sample system profile with flow and pressure (top right) was created using the Kaeser software, during the same time frame as the SAC Plus Power Cost – table (bottom left). As mentioned previously the rating of the CSD 75Ts was incorrect and therefore the specific power is about 18.6 kW/100 cfm. This is corrected in the table on the bottom right. Corrected Specific Power, flow was entered incorrectly originally in SAM
Pressure fluctuations from 115-psig Sample 1 – SAC Plus April 2008 Energy Cost Table (SAM not Controlling System) Pressure fluctuations from 115-psig SAM was running in Manual Mode, the compressors were operating on their own pressure settings. Notice the $300/month Idle Power Consumption compared with the less than $2/month for February when the SAM was running the facility (in Automatic mode). Also notice the poor Duty Cycle of the CSD compressors. Duty cycle of all three units not 100%, so additional savings can be achieved SAM in Manual Mode
Cycling Dryer
Compressed Air Efficiency study
Compressed Air Efficiency Study Key differences from typical energy audits Short sample interval necessary to capture compressed air demand events kW and kWh tell only a small part of the system performance Should include an analysis of wasted air Leaks Inappropriate uses
Leakage Losses Hole Diameter Cost Per Year $ 820 $ 3,285 $ 13,133 $ 820 $ 3,285 $ 13,133 1/16” 1/8” 1/4” This small hole (1/4" diameter) costs you approx. $1,095 every month Based on $0.08/kWh, constant operation and 100 psig If you don’t think leaks can be expensive, take a look at these numbers. A ¼” diameter hole costs $8,382 per year. These figures are based on .05 /kWh. I don’t know if any power company is that cheap anymore.