U.S. Department of Energy - Energy Efficiency and Renewable Energy
Building Technologies Office
Refrigerated Display Case Controls (text version)
Electronic case controllers are a proven technology that can offer significant savings potential to supermarkets and other food retail operators. This presentation provided an overview of case control functionality and how the technology can be applied to commercial refrigerated display equipment to lower electrical installation costs, improve product quality, and provide operation savings related to maintenance and energy costs.
Below is the text version of "Refrigerated Display Case Controls", originally presented on June 25, 2012. In addition to this text version, you can listen to the audio recording of the webinar (WMV 23 MB).
All right everybody. I'm seeing 3:05 Eastern here. So I think we'll go ahead and get started. First of all, this is a housekeeping matter. If everyone who's not presenting or asking the speaker a question could just mute their lines so we don't get anything from the background. So my name's Collin Weber. I'm a Navigant Consulting. I'm here with colleagues Bill Goetzler and Dan Chwastyk.
Today we're going to host on behalf of the DOE CBEA Retailer Energy Alliance. We're hosting a webinar first in a series hopefully that will be ongoing. The purpose of the webinar is simply to provide Retailer Energy Alliance members with a chance to learn about some of the latest advances out in refrigerated display case control technology specifically today. DOE has organized this particular webinar session based on previous input from members of the alliance regarding subjects that are of interest to the retailer end user members. Today we have two representatives from industry leaders. Peter Dee, Sales Director for North America and Canada of Electronic Controls and Services at Danfoss. Peter Dee, just say hi briefly.
Hi guys. Hi everyone. Nice to talk to you all. As Collin just mentioned I am the sales director for Danfoss in North America. As you probably gather from my accent I'm Irish and I've only been with Danfoss six months now. Moved from Ireland to take up this position. This is my first role within Danfoss. Currently in Ireland I set up two businesses. One of them was basically on refrigeration control systems for end users. That's where my experience comes from. My experience is from electrical engineering to refrigeration electronics. I have 29 years in the industry. Thanks Collin.
Thank you Peter. Also joining us is John Wallace, Director of Product Management at Emerson Retail Solutions. John, if you'd introduce yourself please.
Sure. Hi. Thanks Collin. John Wallace, Director of Product Management for Emerson Retail Solutions. I've been in the industry somewhere around 16, 17 years now with Emerson filling technical roles in the engineering department, what started off as CPC and then sort of morphed over the years in Emerson Retail Solutions and then most recently as director of product management responsible for our product and services roadmap and new developments and those kinds of things. I appreciate everybody's time letting us present today. Thanks Collin.
All right, thank you to you both. As stated in the invitation the presentations will each be roughly a half an hour and then we'll have a window of about 15 minutes for questions from the users that are on the phone, end users. So we'll go ahead and dive into it starting off with Peter discussing case controls from Danfoss' perspective. So as a housekeeping as I mentioned earlier I'll be running the slide presentation so if you just let me know, "Next slide," on the time.
Sure. Again, thank you Collin. Thank you again, guys. Basically as you know I am the new sales manager for Danfoss. We've done a lot of work. I will do apologize at the start. A lot of these slides are coming from European format. That's where I've done a lot of my work obviously in Ireland and the U.K. The case study at the end is based on an end user which we rolled out energy saving refrigeration controls. So Collin if you just — what I'd like to do briefly to start off on the global climate to why we should be using refrigeration controls. So next slide Collin.
The global climate. I know you're probably all aware of this but just to recap. The global climate and energy challenge. The climate challenge is fueled by increasing energy consumption, demographics and wealth, of course. By 2050, 70 percent of the world's estimated 10 billion inhabitants will live in massive urban environments. Coming from Ireland, believe me, I've seen that in America. Energy consumption will grow by 45 percent up to 2030. Next slide Collin.
Roughly 7 percent of the electrical energy produced is used in refrigeration which is quite a lot. Efficient controller refrigeration in grocery stores ensures that energy consumption is automatically matched to the actual need. Again, efficiency of control, i.e. case control and plant control. Refrigeration control systems can typically help retail stores achieve 20 percent savings in energy.
Typically help is as depending on the application and what you implement as part of your control strategy. 16 million tons of CO2 could be saved every year if all modern grocery stores globally optimize their refrigeration energy efficiently. Again, the keywords are there is optimize the refrigeration. This corresponds to the CO2 emissions from almost 7 million cars. Incredible, that kind of emissions.
Okay, refrigeration, this is only an example slide basically of the energy percentage used in refrigeration in a retail store. So compressors plant basically 47 percent; condenser fans 12 percent; evaporator fans 19 percent; anti-sweat 18 and defrost 4 percent. Thanks Collin.
Okay, the typical way of controlling evaporators. Thermostat control, one thermostat on/off, same set pipe used, no variation. Mechanical expansion valve, defrost, timer control fixed times, same every day all year round. Fans and electric anti-sweat heaters in some cases 100 percent operation. Can you just pick Colin?
So basically what we're saying is result is high-energy consumption and high-running costs basically just using standard refrigeration control. Next slide. Okay, the intelligent way of controlling evaporators. I'll go through these briefly individually after this slide. Adaptive super heat controls, night set back, anti-sweat and rail heat, pulsing, fan pulsing and defrost on demand. Next Collin.
Adaptive super heat control. We use a lot of that in Ireland in particular and the U.K. So using refrigeration controllers and there is a lot of different manufacturers and case controllers that can give you the same savings I'm finding. So using refrigeration controllers with a unique control algorithm and a combination of pressure and temperature sensors it is impossible to measure the super heat and exactly match it the refrigeration load.
So again, we're talking about data and measurement across the aisle before and after and across it. So accurate and reliable measurement of the super heat the controller controls the valve opening the gate as a true and exact percentage of the load. So in other words we deliver the amount of refrigeration that is just required. This control function can reduce your energy use of the compressors pack by 12 percent. Again, by controlling the refrigeration into the cases you reduce the number of run times and on times for your compressors back in the plant. Next Collin.
Night set back. The controller can have an offset to set point and this again is user to find of the temperature at night basically. The load is low saving the energy. So in other words, some controllers out there have a night set point so when you have your blinds down and everything the duty is not as high so you increase the set point and again reduce the energy load on your plant.
Light, again, refrigeration controllers can manage your light internally by operating them on/off according to the day and night setting. A lot of stores that we found is that they forget to switch them off. This is automated and it can be taken from your front end controller, your master controller within the manager's office. You can also have special holidays as we call them so that during your Christmas period, your Easter period that the times are automatically set in on the front end controller talking to all your case controllers and switch everything off.
Also can be incorporated into your controllers is your cold rooms, your walk-ins. A door switch can be incorporated to switch off the lights when the door is closed but not only that which I didn't add in there if this is connected back into your front end, your master controller again, you can log the number of times the door is opened. Again, if the door is opened for a long period you can create an alarm that will be activated back at the front end system. I do know that there's a lot of systems out there where you have door switches and you incorporate an alarm physically out the door but these can be dismantled or disconnected where if this way it's right back into the controller and again that will create the alarm back at your front end control. Next Collin.
Again, pulsing of rail heat and anti-sweat and fans there's various options what you can do here. It is possible to pulsate the rail heat. Obviously that gives you energy consumption is dropped and this can actually be done day and night time. So during the day with the humidity high the stores are open you can reduce the number of off period so that you reduce your chances of condensation on the glasses. This is going to be incorporated as well through a humidity sensor which can be placed on the shelf floor.
So not only can you have time pulse you can have humidity as well as pulse. There can be a lot of savings to that. Again, using that course for the fans can be pulsated again mainly at nighttime if you reduce the on and off times of the fan. Again, it saves energy from 0 to 20 percent. Again, this is down to the set up of the controller and the understanding of the set up of the controller. Thanks Collin.
Defrost on demand. A lot of intelligent controllers offer defrost on demand. This is just one of them. Adapt a defrosted space on real time monitoring of the evaporator performance. So by using an AKV valve as a mask flow meter is possible to compare the energy balance between the refrigeration side and the air side of the evaporator, i.e. by means of this comparison it is possible to calculate the airflow through the evaporator when it is key.
By monitoring and degrading the airflow through the evaporator it is possible to estimate the ice buildup on the evaporator. In other words, you are looking to call the defrost when it is required. So instead of setting up four defrosts, six defrosts a day you can set it up to say, "Do I really require? Can I look at all these measurements and settings and then do I activate the defrost as of when required?" Obviously the intelligent controllers have built into it that this can be overridden as well. Next Collin.
Okay, this is some of the retails and the tests that have been done in the field in Europe. So as you can see by the percentages as go down through them they're quite high and quite beneficial. If you notice in summertime on the last time, NBE, that there were zero reduction in the summertime. It was required that the defrosts were put in place. Thanks Collin.
Okay, what I want to do is this is a case study and I'll briefly go through that was trialed in Ireland, where my company was involved with major end user. So next slide, Collin. I'll give you a brief outline what we done. What the end user wanted to do and they were going to measure and compare the energy savings themselves. We had no involvement in the energy savings in this project. Well basically it was a small retail store and as you can see —
[Audio skips out]
Peter, are you still on the line with us there? Are others listening in still on the line here?
This is John. I'm still here.
All right. Well let's give Peter a minute or two to reconnect. He might be presenting from out of the office. Maybe he's travelling or such.
Hi guys. It's Peter, again. The phone line dropped on me. I'm actually on my cell. So let's hope this stays in place.
All right. Thank you Peter.
Okay. Can you all hear me okay again? So basically this project was a small retailer of course. As you can see 24 low temperature cases, 48 high to medium temp cases and 9 walk in cold rooms. So the goal here was these were standard PEV valves with an on/off sunlight for controlling the refrigeration on the cases. So we removed all the existing controllers. We installed the EV controllers, the product expansion valve controllers. Prior to doing this the end user collected raw data from an energy management system. The next slide will give us our findings. So next slide Collin.
Okay and if you could just hit click again Collin and bring up the first arrow. Okay, thank you. So what we have was they ran an energy efficient project tracker. The store stayed open while the retrofit was going on. So what we have on the left hand side is the blue. This was actual energy usage prior to the project. So where you have the blue turning to green that was the start tape of the project.
The red line along the top is the projected usage. This was an algorithm I believe from the energy monitoring software on this project tracker. As you see in the middle of the graph it also gives you the ambient temperature, took in all factors. So took in the ambient temperature. So just click Collin. I think that brings that up. So the green then after the project is the actual energy use that was used. If you click again Collin.
So what we had over a five month period. So we replaced all the controllers, set up all the energy efficiency within the new EV controllers as well as going back to its main front end controller which was in the manager's office and then that way then we set up a night set back, lighting times from that controller. Obviously because it's an EV instant saving. The measurements for the five month period was 78,000 kilowatt hours of saving just by changing out the controllers. What I will say this was basically on a site that the controllers were set up by a controlled company and we trained the refrigeration contractors.
The key to case control and refrigeration optimization is actually monitoring after the system is set up and that is the hardest goal to get to is that it is fully tracked and monitored because all the electronic controls and other controls you put in unless they're monitored and set up correctly you will not get your settings and you have spent all that money and you will just not get them. This particular company put in a monitoring and targeting system where that if the energy consumption went above the new settings here, the new savings they'd trigger an alarm. Now this was not true to refrigeration. This was an independent system taking it away from the refrigeration controls company and the contractor. So the key to refrigeration controls is setting up the right control system for your particular use, controlling the case controls back to the front end so that everything is communicating with its plan with the case and optimizing the site to its full potential.
Where retailers in the past make a mistake is that they have set up only part of the system and they don't understand then, "Why do we not get the full potential in energy savings," that certain companies have offered to them. Again, I'll go back to it is that if the contractor makes any changes on maintaining then you are going to lose your savings again. Next slide Collin.
So basically what we're saying is case controls can save you energy however they have to be set up correct. I think that's the pure message here today. Value is going down the case controls regardless of whoever's system they put in they have to be set up and the contractors and the people maintaining your site have to understand as well the benefits of using case controls for your benefit. In Ireland some of the retailers had propensity clauses in on maintenance contracts that if the energy operating costs went up the contractor was penalized and some of the contractors actually lost some of their stores for the following year maintenance contracts.
So that's basically a quick overview of what I put together for you. I know Collin has my details. If you want to talk within more detail I'm more than happy to discuss with you. So if you have any questions I can take them now.
Yes, absolutely. So we have time built in now. So if participants on the line have questions regarding Peter's presentation and his background and his experience then we certainly have time to answer them now. No questions on the line for Peter? All right, well if that's the case then we'll move on to the second presentation of the day, John Wallace from Emerson as introduced earlier. John if you're ready to take it from here.
Yes, I am Collin. Thanks a bunch. Can you hear me okay Collin?
All right, good. Okay, Collin, if you'll just go on to the next slide and then the next slide. I've already introduced myself a little bit earlier. So I've got four topics that I wanted to talk about with you today and one of the things that — Peter and I didn't have an opportunity to review each other's slides earlier so we've got a little bit of overlap in there but I think that's fine. It kind of helps to state some of the points. I think what you'll see is some of the information that I'm going to show is very similar to Peter's experience and some of the lessons learned he talked about I will certainly agree with in terms of the things that need to be done there to make sure you reap the benefits of the installations overall. But in my presentation like I said I've got four basic topics.
Now I wasn't exactly sure what the familiarity of the audience would be necessarily with case control. So the first topic there, the overview and background info is really a little bit more maybe education oriented in terms of what case control really is and some of the things that it consists of and again, for some people this may be a little bit new. For some people it's very old hat but hopefully just a few slides we'll spend a little bit of time kind of walking through it and kind of bring everybody up to roughly the same level in terms of the definition of case electronics and case controls and what you have with case controls overall.
The bulk of the presentation I'd like to spend on the benefits overall and I'm going to talk about the advantages that you can see. Again, much as Peter has shown some of the advantages of case control. I'm going to expand on those a little bit and show what you can expect and how you can go about reaping some of the savings when you do the installations of case controls and kind of change your architecture the way that refrigeration systems have more traditionally been done especially here in North America.
I'm going to touch briefly on wireless as a third topic. Just a little bit of information there. There's a lot of kind of news and things going on about wireless right now. So I think I have one slide that kind of shows you what you might look for in terms of wireless systems and especially with respect to case controls and how you can use the two effectively to know your installation costs. Then we'll kind of wrap it up with a little bit of a summary and kind of a reiteration sum of the points then. Again, a lot of this is focused kind of on education and kind of what we can do with case controls and benefits as well. So next slide, please, Collin.
So I like the graphics. You'll see throughout my presentation I try to do — I like the pictures worth 1,000 words kind of thing. So I try to do more pictures and graphics to illustrate a few key points. What I've done in this case here is shown on the left hand side I've shown sort of a more centralized control system and how it would look if you drew kind of line diagram of it and you showed the refrigeration and the electrical kind of the back of the house or shown near the top of that and then the refrigeration cases that obviously are out on the merchandising floor are shown to the bottom there labeled case 1, case 2 and case 3. Then the wiring and some of the other information you see there those represent power wires and low voltage sensor wiring and things like that, kind of show a little bit of the graphic details between it.
Now on the right hand side of this slide is kind of the architecture of it would be with case controls. So we kind of shifted the focus from the back of the house to putting the electronics and the cases themselves and the bullet points kind of talk about some of the differences there. Now I'm going to bring this slide back in a few minutes when I go through some more of the details regarding the electrical installation of what you can expect but I wanted to kind of use it up front here because I think it makes a pretty good sort of leading slide to kind of show drastically the different between a traditional — and again for North America — traditional centralized control system shown on the left versus a distributed system with distributed case controls kind of shown on the right side. Next slide, please, Collin.
If you try to take those differences that you noticed on the back side, you kind of look at some of the commonalities and some of those kinds of things that's what I'm showing in a little bit more detail here on this slide here in terms of this matrix that I've put together. Just to kind of talk through the different areas of it for just a second. If you look down the left hand side the first column which talks about the functionalities overall that you would expect I've kind of separated it and kind of grouped it into temperature control which is controlling the temperature in the refrigerated cases. A simple concept but yet a lot of details go behind that.
Defrost control. Peter had mentioned that a few minutes ago in terms of the adaptive defrost. Defrost certainly is required for refrigeration systems and no doubt even case controls or non-case controls you've got the same things to worry about there. Load control which is my shorthand nomenclature for lights and fans and anti-sweats and some of those kinds of things as well. So those are sort of three common things. Then the bottom two rows relate more directly to the method of refrigeration system control related to super heat or controlling the metering of the expansion valves. Then the last one is the electronic suction regulators or pressure regulators.
Now I've kind of grouped those are major function blocks and then across the columns I've shown sort of three major control types that you'll find in case controllers. You can probably argue and split hairs a little bit if you want to in terms of the breakdown and you can probably come up with one or two more variations but just in general if you look at the case controls that are on the market today you'll find three major types I would call them.
The first one there which was what I've labeled as Temp Control Only is electronics in the case or case controllers that will control the temperature in the case. They also manage the defrost and then the load control, in other words they provide the control in the switching to the lights and the fans and the anti-sweats and those type of loads but they don't provide any of the other refrigeration system control. The middle column there I've labeled Super Heat Control and this is case controls that provide all of the functions from the first column, the temperature control devices but then they also have controllers and electronic expansion valves. So in other words, they provide super heat control.
Then the last column there you'll notice the big differences. I've labeled it ESR control and these are case controllers that provide — they do not typically provide super heat control but they do provide pressure control in the form of controlling the stepper valve that's an electronic suction regulator valve. So that's actually the way that they would accomplish their temperature control is with that ESR valve.
Now I've got more details on the next couple of screens here but just wanted to reference back. If you notice I've got an A, a B and a C below those different control types. So the A is the temp control, B is super heat and C is the ESR. So Collin if you'll go to the next slide and I'll go back to my simple graphics here and try to illustrate some of the differences between a traditional and mechanical control system and what you would expect with case controls. Again, I realize this is old hat to several people but maybe some good background information and a refresher to others as well.
Now on the left hand side is the way that you would typically control an evaporator in a refrigeration case that doesn't have any electronics in it. The green device there, it's kind of difficult to read but it basically represents a mechanical thermal expansion valve or GXB. Now the thermal expansion valve is the device that regulates the refrigerant metering through the evaporator and is responsible to make sure that the proper amount of refrigerant's coming through. It has key control requirements or key control element of a refrigeration system in general. So that's the TSB part.
Then the mechanical thermostat shown there and granted normally in this day and age you never really have a mechanical thermostat at least in a supermarket case. It would likely be some kind of electronic signal from the rack or something like that but in this case I'm showing you just to illustrate. You've got some way of shutting the refrigerant on and off based upon that liquid mine solenoid that's shown there and that's the way the temperature control would be affected, again, in the mechanical, the conventional sense of the way that you would control the evaporator. So that's the left side.
Now the right side shows the changes that occur when you add case controllers in and when you have a case controller in your refrigeration case. The problem there which I've labeled A corresponds to the first column of the Temp Control Only column in the matrix that I presented on the previous page and in this case what we've done is we've left the thermal expansion valve in place. So the mechanical expansion valve is still there. It's still controlling the super heat but we've left the case controller now to take over the duties of controlling the temperature within the case itself.
The way that that occurs is there is a sensor that's there, temperature probe which I've labeled up to the top there. It's called discharge air. You'll find the nomenclature's different between the different manufacturers but the aspect is still the same. You have some kind of temperature measuring device that is located within the case that connects to as an input to the case controller. The case controller then compares that to some set point and does some calculation. Then the controls, in this case the solenoid valve as a temperature control element around that. So that's kind of the way you'd look at — again, that's the type A control which is a case controller with no electronic expansion valve. So in other words, there's no super heat control with this particular case control.
Now on the bottom picture I've shown very similar but in this case you see I've eliminated the mechanical thermal expansion valve, the TXB and I've replaced it with an electronic expansion valve. Then I've shown a couple of additional sensors that are connected then to the case controller for monitoring the super heat of the refrigerant and then also controlling that with that expansion valve as well. So you still have discharge air which is sampling the temperature within the case itself but you've added in this case the coil in and coil out probe to calculate the super heat and then affect the control for the expansion valve. Now a couple other points on the slide as well. There are several variations on this basic theme but I think Peter had mentioned to the point about a pressure transducer and that is exactly right.
Pressure transducers can be used and many people think they're preferable to use a pressure transducer to coil out probe and then do the super heat calculation with the pressure transducer. So I would certainly agree with that. That is something that can be done as well and used. The other point of that is that just to note that you have multiple sensors that are now connected back to that case controller. I'd like for you to kind of hold that thought just a little bit as that will become important as we go forward here. Next slide Collin.
So just to kind of wrap up this first part of it, I did want to completely show what happens in the case of that third column which was the ESR control or the suction regulators. In this case on the left hand side I've shown a mechanical pressure regulator valve which is the valve that's shown down at the bottom there and the point here would be I've replaced that on the right hand side when you use a case controller with the capability of controlling the ESR valves. You replace that with that mechanical valve with an electronic valve. The advantage of that you're taking a direct reading of the discharge air. So that's the temperature within the case itself and then you're using that to directly manipulate the ESR valve. So you're directly affecting the pressure of that particular evaporator there.
Now a couple points to note here. First of all, I realize on the left hand side the conventional and mechanical drawings in many cases perhaps even most cases there's pressure regulators can be located back at the rack itself but there are different variations in terms of the layout and the architecture that would be applied that way. Then on the right hand side what I've shown this particular case controller to be used on what evaporator in reality in many cases you'll find that a case controller or an ESR valve can control multiple evaporators. So you'll find you may do two or three different cases that are on a circuit with one ESR valve or potentially multiple evaporators within a case itself you could use an ESR valve and an ESR case controller to accomplish that control.
Now in those scenarios what happens is there are multiple temperature sensors. So in other words, multiple discharge air sensors that would be placed in the different evaporators, the different cases that you're controlling and then those values would be averaged within the electronics, the case controllers. So to come up with some kind of average or minimum and maximum pressure regulator to drive the ESR valve. Okay, next slide, please.
All right, we're going to move on to the second topic here which is what we'll spend most of the time today in the presentation and that's really kind of looking at the benefits and the advantages of case controls and kind of what you can expect and to how you can expect to see those. Now I've kind of expanded a little bit here and the way I think about these different areas where you'll see the savings is in these categories or buckets. I've got kind of just a few quick bullet points on this slide and then the following slides kind of give more detail on each one of these areas but to start kind of the top left here, electrical. What I'm really talking about here this is the electrical installation.
So this is kind of thinking of a new build or I guess in some cases a major remodel where you have the opportunity to change the way the electrical wiring, the power wiring that feeders, the branch feeders and things like that are done and also you have the opportunity to eliminate a lot of the center home rounds and things like that. Again, we're going to show some detail on each of these in just a few minutes here. But that's kind of the first category. That's a one time savings. That is an installation savings that does happen one time only. So that's an upfront savings. Our first cost.
Now on the right hand side is refrigeration and piping, what I've labeled refrigerant and piping. In essence what this category provides and again, this is a first cots or an installation savings as well but what this category is talking about is by using loop piping and some of the concepts associated with that which are enabled by the change in architecture and by the case controls you can reduce the copper that you're using up front and you can also lower your refrigerant charge as well. So again, that's an upfront, first cost savings that you can realize by taking advantage of some of the capabilities that the case control and the distributed architecture provides for you.
Down on the bottom, the maintenance and commissioning and energy those are actually ongoing savings that you can realize. The first one there, from a commissioning standpoint is actually — I'm sorry, that's actually a first cost savings as well but that's talking about utilizing some of the benefits of case controls to encase electronics to reduce your start up time. That's the time you spend kind of commissioning a new store, a new installation. Once you do that though there are some additional savings you can realize from a maintenance standpoint by taking advantage of the capabilities and we'll talk about those. Then finally, the last point there is energy and how that you can realize an ongoing savings from an energy perspective. So again, I'm just looking at this kind of from that perspective. Now let's keep on going to the next slide here, Collin.
Okay, this is kind of focusing on the electrical installation. Again, it goes back to the slide that I showed early on and it's really more graphical in nature but I think it does do a good job of illustrating kind of the changes that you would expect to see as you put in a case control store versus a more centralized installation. What you'll see and I've added the table down at the bottom that kind of shows for some of the different elements the control would be and labeled it either the rack or the case. So we'll kind of walk through that part of it first.
So if you look down at the bottom there at the tables you'll see under the centralized control scenario you've got the sensors which are located in the case itself but you'll see the input boards and the output boards which are used to measure the temperatures and actually to do the control and those kinds of things on the relay boards. Those are typically located either in the rack house in the refrigeration room or back in some of the electrical panels as well dependent upon exactly how your layouts are done. The case loads across the VMS case and the central control side are not applicable. That's really more for the case control which is on the right hand side of the chart. It shows the way things kind of layout and the architecture with case controls.
One of the things you notice is you still have the sensors in the case but we've kind of shifted. We do not have the input boards and the relay boards in the rack anymore, at least the ones of those that would be associated with the reads and the temperatures and the controlling of the temperatures. Those now shift into the case electronics which has been distributed and the case controllers would be mounted inside of case one, case two and case three and then I've also shown you electronic expansion valves there too for the stripper control as well.
A couple key things to kind of remember with this chart and kind of look at here is first of all your electronics are really shifting from your electrical panel back into your cases that way. So there is a shift of where those electronics are installed at. Then the other thing to notice is that the wiring, both the power wiring and the low voltage or the sensor wiring are greatly simplified in these cases. What happens is by taking advantage of the fact that you've got the electronics in the case that have the capability to do the load control, in other words the lights and the anti-sweats and the fans and things like that within the case itself you don't have to run those separate feeds out from the electrical to the refrigeration room any longer, the high voltage power feeds. You can run a single 120 volts or high voltage feed out to a case and then have the load switching occur within the case itself. So that enables you to save on your high voltage power feeds and your high voltage wiring.
Then also the other thing to notice too is that the sensors on the left hand side — they're shown in red there — those are basically home runs that go from each case back to the refrigeration house because remember those sensors are in the case itself and we're not running them back. On the left hand side, the centralized control, the left side of that drive we're running those from the cases back to the refrigeration room, to the rack house, to the boards that are in the back. Now the right hand side with case control those sensors are still in the cases but they're now landed directly on the case controllers that are located in the cases themselves.
So the replacement there is the sensors are local and all we really have to do then is run what's called a daisy chain between the cases which is a communications cable that goes between the cases, daisy chain from case to case and then one hop back to the refrigeration room itself to the supervisory system or the bass or the head end system that you would have in the back of the house there. So you can see the simplification that does occur there in the wiring overall. Collin, if you'll switch to the next slide please I think there's just a few more details in terms of the way that those savings occur.
You can see at the top there line voltage, the reduction. This saves 30 percent. I've seen between 30 and 50 percent fewer branch feeder wires run the high voltage which is a fairly significant amount of the electrical installation dollars for a new store or a major remodel that way as well. But anyhow with fewer high voltage feeds up there is the possibility to reduce the number of circuit panels and the breakers and the things like that. So you want to assign somebody that can kind of work and understand how to do the upfront design with case controls and the re-architecture and the more distributed system so that they can take advantage of that architecture and rework your electrical systems to take advantage of that as well.
The homeruns we talked about. The low voltage wiring, that's the sensors and eliminating those sensor wires that have to go all the way back to the refrigeration room in a traditional system. We're not just again landing them locally on the case controller itself and just running a very simple easy to run daisy chain between the cases back to the refrigeration back controller which is in the back of the house as well. So a lot of wiring savings, a lot of installation savings by taking advantage of the distributed architecture, the way that case controls really kind of sets up and allows you to do there.
The last one on that slide I think is pretty important as well and sometimes we tend to overlook that a bit but by kind of shifting the electronics and a lot of that labor and wiring from the field into the early end factory you can realize a lot of advantages because factory check up, they can do it on the floor. They've got automated procedures and things like that and it's just much easier and much simpler to do that at the early end factory but when the case arrives onsite it is all set, ready to go. It's been tested. In most cases the early end will provide a very simple wiring distribution block that's labeled, "Land your cables here," and it just makes for a much easier and cleaner field installation and really reduces the time it takes onsite for the electrical installation and hookup of the cases overall.
So the next slide, Collin, is kind of addressing the second part of those benefits or that category that I was talking about and this is really relating more to loop piping. Loop piping is shown on the right hand side there. This again is an installation of the first cost savings that occurs between a — I like simple diagrams so I've used a simple diagram here to kind of show the difference between the two types of systems. On the right hand side is what I term a conventional system which has the rack and the condenser and that's generally in the back of the house or it could be on the roof.
Then the cases, case one, case, two and case three in this case are shown supermarket cases that are out on the merchandising floor. Each one of those cases has two refrigerant lines running to is, liquid and suction line running to it as well. Then you'd see the generally the temperature of the default control and those kind of things again on the conventional system would be back in the rack room itself, back where I was showing in the previous drawing, the electrical drawing.
Now a loop piping system is shown on the right hand side and as you can see the diagram certainly is a lot simpler. What happens is you basically run what's called a loop system out and then you T off of the refrigerant lines that are coming out on the floor there and instead of running the equivalent of the homeruns all the way back but in order to do that you have to have some kind of local control within the case itself to do the temperature and the defrost control locally there. So that's one of the key pieces is that you've got to be able to do that. That's why the architecture really facilitates the loop piping to do that. Well there's less copper and I think I've shown the results of that, too. Piping and fittings and installation, and so forth that you would see for that overall.
I saw different studies that show anywhere from 30 to 50 percent even a little bit more piping savings. So in other words, that's copper savings. Again, that's the first cost that you'll see a reduction in the installation there. The other side of that too is because you're reducing the amount of lines — if you look at it there's a pretty good reduction in the amount of piping that's there you could also reduce the initial refrigerant charge. Again, I saw numbers anywhere from 8, 10, and 12 percent, something like that. So you take both of those together and there's a fairly significant amount of reduction overall in the installation costs because the loop piping and then also reducing the refrigerant. Next slide, please.
So switching gears here just a little bit. I was wanting to talk a little bit about the start up time and how the case controls can facilitate a reduction of the startup time overall. When I startup time really what I'm talking about is this is on a new installation or a new refrigeration system where it can be a ground up build or it could be a major remodel and you need to commission and start a refrigeration system. It involves things like checking to see whether it's working correctly and kind of all those things.
One of the reasons that this is important is to reduce the time. It means you can open the supermarket quicker or in the case of remodel you can kind of get out of the merchandiser's hair so to speak and kind of get things all set and run them in a much faster way. The way that case controls can help you do that in actually a couple ways. We've already talked about this, the leak checks and the refrigerant charge but one of the other major aspects of a startup is kind of ensuring that all of the — in a traditional system using mechanical expansion valves making sure that those expansion valves are all operating properly and in order to do that it does involve or it can involve a fairly significant amount of time to measure and to check that things are correct and let the system settle out overall and then to go back and to check again and adjust.
So the advantage with using a case controller with the electronic expansion valve is that that time the case controllers are basically optimized from the beginning. As I mentioned you're using sensors to measure the super heat instantaneously and then doing an instantaneous control on those as well. So I like to say that they're continually optimized that way. Now that's a part of it.
Then the other part of it that lends itself to shortening the cycle as well is because the additional sensors that are in place that we talked about a few minutes ago you can also have access to those sensors and see those measurements without the technician having to install any extra equipment at all. So in other words, traditionally you might take a gauge set or something like that and connect it up and then watch the gauges by using gauge controls in the appropriate software and supervisory systems. He's got all that data available to him right there. He doesn't need to connect anything at all.
This is just a screen shot from a software package that's used to measure and monitor. You can see coil temperatures, super heats, case temperatures, valve percentages. All that information is available to the technician with really no additional effort at all. Virtually all of the control manufacturers offer this kind of information. The key is getting the controllers installed from the factory, the sensors wired up and now all of a sudden you have access to all this additional data without a technician over to connect a gauge or do anything at all.
From this standpoint just with the data and the TXCs and the electronic expansion valve control with the super control versus the mechanical valve you can save anywhere from three, four days up to maybe a week or more of onsite startup time, commissioning time. Again, when you're shaving time if you can shave a week off of your startup time that means your store is open sooner which means you've got a quicker time to revenue. So you can start generating dollars much quicker that way. Next slide, please, Collin.
Switching gears just a little bit here. We're still talking about benefits and the categorization but I want to talk a little bit about the maintenance savings that I've termed operational cost reduction. So the previous slides were really talking about sort of those one time savings that I talked about before. Those are installation savings that you can see, startup time savings and things like that but you also have these ongoing or life cycle savings as well. One part of those are the maintenance savings that you can realize.
We talked about the labor costs here. We talked about the additional sensors just a second ago in the previous slide. The thing to remember is that advantage doesn't go away once the startup is completed. Those sensors are still in place. They're generating data and that data can be accessed remotely to diagnose or troubleshoot any problems or issues that may become aware of that way.
In many cases you can take that to another level by even doing some kind of remote step point adjustment or those kind of things to check to eliminate a service call or a truck roll but even if you can't do that just having some troubleshooting that occurs before you go onsite and having that additional data so that you can look at kind of how the system is performing overall can be very valuable information to provide to the technician that is going onsite then to fix a problem. So it's a little bit of a soft savings. I realize that but I wouldn't encourage you not to underestimate the impact that that can have overall. The material costs, the internal carrying costs. We talked about the leak rates and the inventory is really from a communization of some of the parts that you use in terms of the sensors and the electronics and things like and being able to carry just your technicians to kind of have a common set of parts to carry on their trucks as well for you to inventory overall.
Then that last point, again, that's actually a pretty important point I believe because with the data that's generated and the ability to analyze that data remotely you can now let your technicians, maybe your more advanced or your senior technicians kind of put them in a position of this remote diagnostics role and kind of looking at those systems overall and helping to provide their expertise to technicians maybe who have a little bit less experience as well and using that to continue to create a knowledge base that you can use and draw upon for years and years and years.
Peter had mentioned in his presentation too. He made the point that monitoring after the system is set up is really one of the keys to make sure that you're getting your money's worth out of it. I do agree with his point there. I would say that I think there's different ways to do that. The energy system is certainly one way to do that.
I think a system where you're looking at settings and things like that in much of the way that I've shown here is also another way that you can do that as well. If you've got a good process in place to, say, on a regular basis check to see how the system is performing and operating and if changes have been made that maybe should not have been made, those kind of things those are very easy to do once you've got this data and you can look at it remotely this way. So I think that certainly lends itself much easier to this remote check up and this remote checking to make sure that things are operating correctly and that nobody's changed anything that shouldn't have been changed on the system overall. Let's see. Next slide, Collin.
Then the energy, I think that Peter also touched upon this as well. I'll just say a few quick words about it here in the presentation. I think there is a couple scenarios where your energy reduction comes from that you need to be aware of. When you look at the comparison versus a mechanical expansion valves and those would be the ones that I kind of showed earlier, the TXBs and the mechanical expansion valves those tend to have paratactic losses associated with them or that's overall energy that's required to operate the valve itself to go into that. You don't really have that within an electronics system because first of all they're optimized to make sure that they're controlling to the right super heat all the time.
Then the other side of that is those valves are operated electronically so it overcomes or it doesn't have the necessity to utilize energy within the refrigeration system itself to operate those valves. So one of the things that you want to make sure that you're aware of when you apply case controls is the port that you can actually lower your condensing pressures that are set up back at the rack itself because you're using the case controllers itself. Again, kind of pointing back to Peter's presentation as well I think he mentioned that you really need to understand the full inner operation of the refrigeration system, not just the case itself. I would certainly agree with that.
This is one of those areas too where when you look at the system as a whole meaning you look at the cases, both the rack and the condenser and you make sure that the whole system is optimized that's when you can get your best bang for the buck in terms of the energy savings overall. I mentioned the three areas down there as well on those but those are areas that most of the case controllers that I am aware of today have the capability to do anti-sweat control and then lighting and then certainly the defrost termination and the demand defrost that Peter mentioned as well is another area to make sure you keep in front of you in terms of the savings and the opportunities that are available that way. Next slide, please.
So kind of putting all those benefits together and trying to kind of wrap up what I call the value story overall I like to use a very simple method of looking with that. Then this slide I tried to show that graphically where you have — above that horizontal line there you have your savings opportunities, let's call it, and below that horizontal line are your costs. If you look at your savings opportunities — again, we've talked through these. You have the electrical installation and the piping and the refrigerant which are a one time savings, the electrical I think I mentioned a potential of 40 to 50 percent installation savings by reducing the number of wires, changing the architecture of the electrical controls overall, piping savings and refrigerant, 50 percent piping or 10 to 12 percent fill typically from a reduced refrigerant charge and then even the startups out of that you can reduce that by let's say a week or so kind of helps out overall.
On the right hand side the maintenance, leak reduction and then the energy, I've termed those life cycle savings. So those are savings that are yearly savings. So in other words they go on and on and on. They're not the first costs or the one time savings themselves. So those kind of help pay for themselves over and over and over again. So the top part of that is the savings and the advantages that you can realize. On the bottom part is the cost perspective.
There is certainly an increased equipment cost from the case early end because they are mounting more content, mounting more electronics in the cases themselves. They're adding labor to the cases. Remember I talked about how one of the advantages is being able to do all the check out at the factory and those kind of things. So that's not free. It does come at a cost itself but I believe when you look at that increased cost it's more than offset by the savings that you would see especially the installation savings and then the life cycle savings itself.
Now from the first cost perspective I've seen two or three studies that kind of show different results but they all sort of converge on the cost for a case controller store is somewhere — is a few thousand dollars more if you look at it from a first cost only perspective. I've actually seen them from a slight savings in first cost, again, considering when you offset the increased cost of the cases from the OEMs against the installation savings by the electrical and the piping and those kinds of things. So I've seen everything from a slight savings with case controls as far as to a few thousand dollars, say, $5,000.00 to $10,000.00 additional across the store itself. So a lot of that depends on the architecture, your electrical contractors, kind of how they're managed and those kinds of things but its overall. It's somewhere in that range.
Then certainly when you combine that with the energy savings that we were talking about earlier and some of the savings, the soft savings that you'll see from the maintenance side it's not hard to see a payback. It's certainly less than a year and a half, two years, something like that fairly easy. I've had a couple different round tables let's call it and discussions with people that have used case controllers for some time and it's kind of funny because one of the things that I see is that when they've used it and they've been able to apply it successfully and kind of understand how to manage the installations and things like that they really don't even question the value of it anymore. It's just it becomes a no-brainer to install that and it's not even a question of when a new store or major remodel comes around. It's there's by default, the case controls are. So they're really been convinced of the value story and applying it over and over again. Next slide, please, Collin.
Next to the last slide. Here again, I wanted to just put one slide in on wireless. I know there's a lot of talk and discussions about that now. A couple things to be aware of. Sort of the newest installations now are using what's called mesh based systems. In a mesh based system it kind of contrasts to the older point to point system.
The advantage of a mesh system is that the nodes — and I'm kind of showing the picture on the right here — each one of those cases or the walk-in has that little kind of square thing that is intended to represent the electronics that in the case and those red lines actually indicate the RF or the path that the wireless would take to reach back to the master. Now I've also shown in this slide the grey box that's located up there at the top. It's a picture of the E2 which is the supervisory system. The point is that the way that the data transitions back from those cases instead of having the farthest case that's located down here on the right hand side to make it all the way back to the supervisory system it really just has to make it to its nearest neighbor and then the neighbor can perform a path that allows it to hop. So that's the advantage of the mesh based system is it really is auto configuring and it has an element of what I call self-healing in it as well in cases where you're changing the parameters with the layout and those kind of things.
Now on the bottom part there in terms of the best applications what I've tried to do is kind of look at it and say there's a few applications that it's a no-brainer, a lot of sense then and there's some you may want to think about a little bit more. Mobile cases and I put that kind of in the center of the list there but mobile cases are one which kind of — they roll around and typically you plug them in. They're very difficult to monitor or have been traditionally but I think wireless does provide an opportunity to monitor those relatively easily now. So actually that is a very good use case for them.
Also kind of remodels and additions and the thought usage in some of the re-buildings where it's a little difficult to run the communications cable to the different cases. That's that part as well. Well again, not a lot of detail here but just pretty much something to be on the lookout for as well as it applies to case controllers and helping you lower the installation costs. Next slide, please.
Okay, this is just the summary slide and hopefully what you've seen is I've tried to provide some background and some information and then show the advantages and half of it that you can utilize and how you can realize some of the advantages of case control. I think if you add the numbers up certainly I would encourage you to do your own math and I can help provide you with information if you'd like for that but you'll need to calculate your own payback but generally what I've seen is paybacks that are certainly less than two years once you consider all the installation savings and those kind of things as well. There are a couple things.
As Peter mentioned earlier there's a couple things you'll need to do to realize those paybacks but I do believe there's a nice payback that you can put in place when using case controllers as well. The other thing I would encourage you to do is not think about it as a onetime decision or exercise and be done with it. That rich data set, in other words, the additional sensories that you have in place and the data that you have available to you either onsite or remotely really are very nice and can help you with a remote analysis standpoint, kind of lower your maintenance cost overall and really take advantage of your technicians in a much more effective way. Then finally we talked about the wireless just a second ago.
So that's the presentation that I put together for you. I think there's a few minutes left for questions here Collin is you wanted to — I'll tell you you put it back over. By the way, my contact info is there and I would love for you to e-mail me or call me either one if you have any other questions you don't necessarily want to share during the presentation here.
So as John mentioned there is a little bit of time left in their window here. So if we have any questions from anyone on the line feel free while we have John with us. All right, well if we don't have any questions from the callers on the line I want to thank Peter and John both for their participation today. Excellent presentations. Informative. They covered the current data technology very well.
So we really appreciate you on behalf of the DOE CBEA and the Retailer Energy Alliance, taking time out of your busy schedules to discuss this technology with us today. I just want to present one quick conclusion here which is to point out that, for one, we should have an additional Webinar coming up sometime this summer. It should be on hydrocarbon self-contained refrigeration which is a new and sort of emerging technology within the US market at least. So look out for an update or a date regarding that.
Secondly, we just wanted to point out that the Webinar series is driven by the desires and interests of the end users and CBEA Retailer Energy Alliance members. So obviously any ideas for future Webinars, areas that are of interest to the end user community we would certainly love to hear them and you have our contact information. So if there's no other points outstanding I want to thank everyone, both the presenters, again, for your time and to everyone else who listened in. Thank you and have a good day.
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