Episode 12 - Dairy farm energy use - UMN Extension's The Moos Room
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Joe Armstrong: Welcome back to the Moos Room, hosted by the University of Minnesota Extension. I'm one of your hosts, Dr. Joe Armstrong, and as promised, this is part two of our time with Kirsten Sharpe, Dr. Bradley J Heins' grad student. Today it's all about energy use, how we're using energy on our dairy, and where we can improve. Enjoy the episode. Thank you for listening. Maybe give us some background. I know we talked about, Brad already told us that a normal household uses, would you say five to seven kilowatts?
Bradley Hines: Yes, kilowatts.
Joe: Yes, what about a dairy? How do we get our hands on? What does a dairy use for energy?
Kirsten Sharpe: Prior studies really use only energy audits. They get, for example, all of the equipment that's in the barn, the motor sizes, how long all of those components are run and they estimate energy use, electricity use and it's not really based off of actual electricity consumption. Some prior studies have found that, usually, a dairy farm would range from 400 to about 1700 kilowatt hours of electricity per cow per year. That's a wide range and it's really dependent on the type of farming system that you have, your management styles, everything like that.
Really, it depends on, like I just said, your farm and your management and your barn and the components you have in your farm as well. It really varies. This study that we wanted to do was, similar to what I said before about the swine barn study, we wanted to collect electricity data from dairy farms. We wanted to do this because as we all know, consumers have really been demanding products that have a smaller carbon footprint and they seek those products out in the grocery store. The dairy industry is really working on sustainability and wanting to be more marketable to consumers.
We wanted to be able to help producers find areas on their farms where they might be able to reduce their fossil fuel consumption. Really specifically looking at different electrical components that they could work on reducing electricity use with the hopes of the producers taking this data, looking within their own farms to see where they could do that, and in the end, be more marketable or be, what's the word? Consumers would want to buy those products more, if that makes sense.
Joe: Yes. Is there benchmark data already so that you do an audit or you figure out what you're measuring, and then you say, "All right, well, actually, this component of my dairy is taking this percentage of my electricity bill or whatever"? Is there something that they can compare that to to know what that number means? Is it normal, is it abnormal, or is that part of the study as well, you're trying to find these benchmarks?
Kirsten: Yes, so that was part of our study. This study is really unique because we actually went into the circuit breaker panels and installed energy monitoring equipment so we can actually see just how much every electrical component on a dairy farm is using, so fans, lights, pressure washers. We see every individual load's consumption. In that sense, we are providing actual energy use data and providing that data as a benchmark for farmers to use. There are, like I said before, audits available out there, but again, they don't necessarily use actual data.
Joe: That's cool.
Bradley: Sometimes a lot of it is based on what the farmers tell them. If they go out and say, "Oh, well, you have 10 fans." "Yes, I usually run them about half a day," and then you can do some calculations, but we know exactly how long your fans have been running and all of that versus trying to take a good guesstimate at it.
Joe: Before we get too much further in what you found and all that, let's talk about the farms, right? Because I would think size and all that stuff is going to come into it, right? Did you have a good range of different sizes? Did you have different ranges of building design? How did that all work?
Kirsten: We had five farms and they ranged in size from, our first farm was a 9,500 cow farm, a freestyle cross-ventilated barn. They milked their cows on a 106-stall rotary parlor. That was the biggest farm in our study, 9,500 cows. We had another farm that had 300 cows. It was naturally ventilated. They were a robotic farm and they had been using Lelys since 2016. We had another farm that had 200 cows. Again, that was naturally ventilated with a Double 8 Herringbone parlor. We had another farm that was 400 cows. It was naturally ventilated and they actually had a typical parlor and they transitioned to seven Lely milking robots in October 2019.
We were monitoring their electricity from July 2018 until December 2019. We could see when they transitioned to robots, at what point during what month they transitioned. They basically shut down their whole parlor and went to robots and didn't go back to their parlor. That was very interesting.
Joe: That's really cool. That's a great opportunity.
Kirsten: Yes, to get that data. Then our last farm was the farm at the West Central Research and Outreach Center. Definitely the most unique because it is, again, a low-input and pasture-based dairy, so e don't have cows inside. We don't necessarily have fans for cow comfort and stuff like that. We had a wide range of farms.
Joe: You guys have a super fancy parlor, right?
Kirsten: At the WCROC? Oh, yes.
Bradley: Oh, yes, very fancy.
Kirsten: Oh, gosh.
Bradley: State of the art. Actually, it is state of the art.
Joe: Well, now it is.
Bradley: It is now.
Kirsten: Yes, and then we've had [crosstalk].
Joe: It's a swing, isn't it?
Bradley: A swing parlor, yes, with Afimilk.
Joe: There you go. Okay, so you did have a big range of farms, which is great. I think people are always wondering, well, does this really apply to me? You seem to cover just about every size farm. Maybe not the 60-cow stanchion barn, but that's okay. That's hard to do, so that's good. I'm glad you guys got a big range. A lot of different-sized dairies, different barn designs too, which is really cool. Robots, no robots, one that did both. What did you find? Give us a general overview of what's using the most power on most dairies.
Kirsten: Again, these farms were so different that we did find quite a few differences in our results. Across all five farms, we monitored over, I think, Brad, was it over 300 electrical loads?
Bradley: Yes, a lot.
Kirsten: We have a lot of data. We collected the data on a daily basis, an hourly basis, and a minute basis. We could actually see what these components were using minute by minute, which is insane. That's a lot of data, pretty much on the bigger farm, Farm A, they used their most energy, electricity towards ventilation. They typically just manage their fans. The herdsmen manage their fans. Basically, they were on or off.
Joe: That was the big cross-vent barn, right?
Kirsten: Yes. Fan use in that farm was pretty high compared to the other farms on a production basis. They also had a separate vet room in this farm, which they had their calf room was connected to that vet room as well as a fresh cow milking parlor. They had, I think it was 19 or 22 electric radiant heaters.
Joe: 22?
Kirsten: Yes. I think it was 19, I'm pretty sure, but that's a lot. Electric radiant heaters are great for heating objects, but they use a lot of electricity. You can see that in this farm as well. A lot of energy was being used for those heaters. For the other farms, the 300-cow robotic farm and the 200-cow farm that didn't have robots, they, again, used probably most of their electricity for ventilation just with panel fans over the stalls. Farm B actually was interesting. We were monitoring their generator block heater. All of a sudden, we noticed in July that this block heater was running full bore.
We told the producer and they got an electrician out there and they found out that their thermostat was broken, and so the block heater was just on constantly. That's cool that we saw this in their data and we actually saved them several hundred dollars a month by finding this issue.
Joe: That would be expensive. Really expensive.
Kirsten: Yes, so that was pretty neat.
Joe: I'm sorry, I'm looking at the data here and something's jumping out at me. Farm D, 34% for manure?
Kirsten: Yes.
Joe: What's going on?
Kirsten: They have a manure composter for bedding the cows. This was definitely their largest user on Farm D. They're using this for other beneficial reasons that benefit themselves as a farm. Another thing about this farm is that they also tend to keep their lights on 24/7. You can see that their lighting usage is pretty high. We actually talked to the producer and showed them where they were using their most energy. They told us that they were going to look into turning their lights off more.
Joe: I think there's some benefit to long-day lighting, but it has to be installed correctly. There's very specific recommendations for how high it needs to be, how much it covers, all that. If you're not meeting that, probably not a good reason to have the lights on all the time.
Kirsten: Yes, for sure.
Bradley: When some of these farms were converting to LEDs as well. Some farms had LEDs, some did not, some were converting. Our parlor at our research center is not LEDs. We'll admit it that the university's a little behind everybody else.
Joe: Imagine that.
Bradley: You can see some of these things that one farm was converting to LEDs and I think that'll help them out in the future. It's just finding enough money to be able to do that and see what's going on.
Joe: Fans, ventilation, were a big pole. Looks like cooling milk may be also a big pole.
Kirsten: Yes. Farm E, which is the West Central's farm, we have a plate cooler that we're pulling heat off of the milk and storing it in a hot water storage tank for washing later on. We have a huge electric heat pump that basically does that operation for us. That's why you see milk cooling in Farm E as being pretty high compared to the other farms.
Joe: You're also spending less on water heating, right? You're not heating water to clean with as much because you're storing that heat.
Kirsten: Yes, exactly. We also like to plug in quite a few milk house space heaters in the WCROC's farm to keep our water lines from freezing, to keep our milkers nice and toasty in the locker room and the office nice and warm. Again, you see a big jump in electricity use during the colder winter months due to those space heaters. You know you have to keep your employees nice and comfortable too if you want them to work hard.
Joe: Yes, labor retention is a key.
Bradley: A $30 milk house heater costs you about $4 to $5 a day to run. [chuckles] They're really expensive to run.
Joe: They are. That's crazy expensive.
Bradley: It's crazy.
Joe: Wow. All right, well, give us some conclusions as far as if I'm a producer and I can figure out where this energy is coming from or even if I can't, what do I do? How do I start figuring out where I need to spend some time in making some changes?
Kirsten: Brad probably can talk about this a little bit more than I can. Really, the goal was to pinpoint these areas of high electricity use and for me to provide the results for producers. I did do a little investigating on some maybe energy-efficient technologies that could be installed that farmers could use or maybe even looking into some renewable energy technologies. Again, integrating that into your farm could have, like I said before, multiple benefits. Maybe Brad can talk a little bit about some technologies farmers could look into installing on their farm.
Bradley: Sure. I think the big thing that we found about this was just being able to monitor your farm and knowing what's going on is probably the big takeaway because most people probably don't know what's happening. I think that was eye-opening for us that we saw some of these components, especially that generator block heater. The farm probably would've just gone on and just our electricity bill went up and we don't know why. That's a good thing. There's a lot of things that even farms at all ranges can do. When we started this project on our dairy, we actually started it in 2013, we started monitoring our own dairy at our research center.
We didn't have a VFD on our milk pump, which is there's a lot of dairy farms in Minnesota that don't have VFDs on a lot of things. Even just putting a simple VFD on a bunch of motors can help. We were able to put a VFD on our milk pump and it probably has about a two-year payback. Things like that can make changes fast.
Kirsten: It really saved us quite a bit of money too installing that VFD a lot.
Joe: Let's define VFD just in case anyone's lost?
Bradley: Variable frequency drive. It makes the motor run a little bit slower when it doesn't need all that energy.
Joe: Perfect. Same concept with variable speed fans and things like that.
Bradley: Yes. We can see it on one of the farms that we were on, their fans didn't use as much energy because they had VFDs on every motor on their fans. That helped out too. I would make some of the changes that you can see right away, VFDs, LED lights things like that before you really decide to figure out some of the other components. One of the other parts of the project we were trying to figure out, we had a student come from Germany to actually do some work with us as well, where she took one of the farms and modeled it and actually tried to figure out how much renewable energy they would need to save all their electricity.
We modeled it after the large farm and they would probably need a large wind turbine and some solar to be able to offset their electricity use. We can look at some of these other farms and maybe renewable energy, maybe solar is one of the way that they could go to save some of the energy on farms. That was the end game of the project, just trying to figure out how farmers can reduce their cost.
Joe: I really like this research. It's super applied, it's super direct, and it matters a lot. It's not hard to find the takeaway. I really appreciate that.
Bradley: We need to give a shout-out to the Environmental and Natural Resources Trust Fund. That's the granting agency that help fund this. They put up the solar panels, they assisted Kirsten with her graduate student work. We monitored all the dairy farms with us, so really without their funding. If you don't know, that's lottery money that goes into an environmental fund in the state and they provide funding for projects to help reduce the environmental impacts in the state and that's really how we got it. Certainly grateful for their funding from the state legislature.
Kirsten: Yes, lottery money as in literally when you buy a lottery ticket. Buy more tickets, people.
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Joe: Perfect. Any anybody else you want to thank besides Brad, Kirsten?
Kirsten: I would like to thank all of the farmers that let us do the energy monitoring project on their farms, for trusting us to traipse through once a month and collect the data. Dairy producers are awesome people and without them, we wouldn't have been able to do this. Thank you to the producers.
Speaker 1: Bonus question.
Joe: I just thought of a question that I completely forgot to ask. The monitoring equipment, how practical or impractical or expensive, if you wanted to do something like that, maybe not as strenuous as you guys did, but do something like that so you could track this stuff on your farm, how hard would that be to do?
Kirsten: For sure. You can purchase the equipment online. The main data loggers that we use were called eGauge data loggers. I believe that you purchased the sensors at the same website as well, so current sensors. It's pretty easy to install. Luckily the researcher that we had helping us to install knows a lot about installing this equipment, but it's fairly straightforward. I could go in myself now and install one myself. It can be a little, I don't know if sketchy is the right word, but in order to power the data logger, you need to basically plug it into an empty circuit breaker.
You need to turn the power off and everything like that, but it's pretty straightforward to actually go and install this yourself. Cost, Brad, I think the data loggers were $900 a piece.
Bradley: Yes, it was somewhere in that $1000 to $1,500 per farm to monitor them, really.
Joe: Even at that cost, if you're catching that block heater, it broke even pretty quickly, right?
Bradley: It paid for itself really fast.
Kirsten: Yes, it did.
Joe: I just completely forgot to ask that. I meant to ask it earlier because we had said that's an option, but I didn't know if that was truly an option or if that was just a research thing only, but it sounds like it'd be pretty easy to do.
Kirsten: Yes, they're available. These data loggers are available at egauge.com and you can purchase them for your house. One of our scientists has one in his house that he uses to monitor his house use. We actually installed one as part of a--
Bradley: He's monitoring his pool. [laughs]
Kirsten: Probably.
Joe: He wants to know how much energy is the pool taking.
Bradley: Exactly.
Joe: I see.
Kirsten: We did this partnership with the City of Morris and we actually installed some data loggers on the liquor store and the library. They're pretty easy to use and not too expensive.
Joe: Cool. All right, well, I think we'll call it a wrap there. I'll do the ending. Thank you, Kirsten, for being here. I really do apologize for just whiffing on your name early in the episode.
Kirsten: That's okay.
Joe: I'm going to have to leave it in because I think it's going to be hard to edit out, so no way around it. Everyone will get to hear me put my foot in my mouth. I'll buy you a beer. How about that?
Kirsten: Perfect, yes.
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Joe: One more time, a big thank you to Kirsten Sharpe for joining us on short notice. We hope this two-part series gave you something to work on your dairy, gave you some things to look at, and some goals for the future if you're looking at using renewable energy, especially as a shade source as we talked about in the first part. As always, if you'd like to learn more or need something to reference, please visit extension.umn.edu. That's extension.umn.edu. If you have any questions for us, comments about the show or ideas about what you'd like to hear, send them to themoosroom@umn.edu. That's T-H-E M-O-O-S R-O-O-M @umn.edu. Thanks for listening. Catch you next episode.
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Kirsten: Perfect.
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