Padge LLC Prevents Harmonics Damage
Joseph Chacon, CEO of Padge LLC, discusses the impact of electrical harmonics on wind turbines and solar systems, providing insights into causes, consequences, and effective solutions for improving power quality.
Sign up now for Uptime Tech News, our weekly email update on all things wind technology. This episode is sponsored by Weather Guard Lightning Tech. Learn more about Weather Guard’s StrikeTape Wind Turbine LPS retrofit. Follow the show on Facebook, YouTube, Twitter, Linkedin and visit Weather Guard on the web. And subscribe to Rosemary Barnes’ YouTube channel here. Have a question we can answer on the show? Email us!
Welcome to Uptime Spotlight, shining Light on Wind. Energy’s brightest innovators. This is the Progress Powering tomorrow.
Allen Hall: Joe, welcome to the show.
Joseph Chacon: Thank you. I appreciate it.
Allen Hall: Well, I’m glad we connected, uh, through Jon Zalar, I believe, and we don’t talk electrical power creation or what that. Kind of power we’re creating and what the effect of that power is on systems downstream very often, uh, the Uptime podcast, because there’s so many wind turbine issues, is mostly focused on mechanical problems.
But we’re finding that more and more problems may have an electrical origin. We wanted to get an expert in here that would be you to come help us on harmonics because there are requirements about harmonics.
Joseph Chacon: There are, uh, IEEE five 19 governs [00:01:00] the requirements for harmonics. At the point of common coupling.
Allen Hall: That’s correct. And your prior experiences with ge, which is now GE Renova down in South Carolina, that’s correct. But you were involved, maybe give a brief description of the things you’re working on because when electrical people talk, um, kind of gets lost in translation. You were knee deep, maybe waist deep, maybe eyeballs deep and electrical
Joseph Chacon: power at GE Renova?
No, not, not knee deep, not weight deep, waist deep. I was baptized, completely immersed all the way in. I came shortly after the Enron acquisition. Um, I was one of the electrical engineering managers at the time. We had, uh, I think two or three at the time. Um, this was pretty early on. Uh, I got out of that because, uh, I’m, I like management, but I, I like electrical engineering, so I wanted to go back to being an individual contributor.
Um, so I’ve touched just about [00:02:00] every electrical thing you can think of in a wind turbine. And also in solar
Joel Saxum: as well. You know, a little bit of a sidebar here ’cause I want, we want to definitely get into this deep technical conversation, but Joe, you touched on something that happens to people, right? You’re a really good engineer, you’ve run a team, you’ve solved some problems.
So now you get promoted to management, but you don’t get to engineer as much anymore. So you get, like, you get, you start being leadership and like doing all these things, how to manage people, how to run a team, this, that, and that’s great. We need that. The industry, every industry globally, we need to be able to do those things.
But for engineers that have engineer at heart, and I’m, I’m also looking at you, Alan Hall. Uh, they, they wanna be able to engineer, right? They wanna be able to do stuff to make a difference to, to, to get hands on with a problem. So, so you, so you’ve done that though, right? That that’s you, you are now, uh, Josh Shahan is, uh, pad LLC and
Joseph Chacon: pod is short for Padre, which is what my kids and grandchildren call me.
They just shortened it from Padre to podge. ’cause saying two [00:03:00]syllables was too much and I liked it.
Joel Saxum: Yeah, I like that. Okay, so, so, so like we said, uh, you, you, you guys, you’re getting deep into harmonics and other issues. You get called in by Solar Farms to solve problems and, and this is the thing Alan and I were kind of talking about off air a little bit is.
W we have a bit of a culture like in wind right now of electrical problem, swap, swap apart, swap apart in, swap apart out. But nobody’s looking at the, the root cause of why or why did this thing fail, and how can we, you know. Make this more robust for the future. And that doesn’t just stop at components in the turbine.
It’s, it’s BOP, you know, and this is, like you said, also solar and, and other industrial facilities as well. But that’s what you tackle, right?
Joseph Chacon: Yeah. And you know, you mentioned John Zellar, uh, great, great root cause analysis guy. Uh, does fishbone, uh, ad modeling, things like that, um, what’s your observation that you’re seeing?
I think is correct. People ignore. [00:04:00] One of the fundamental root causes for a lot of issues, um, not just in renewable energy, but anywhere you have, uh, large amounts of nonlinear loading, uh, these days. That’s primarily coming from data centers. Um, with the advent of the diode six pulse front end, uh, variable frequency drive, uh, IGBTs, any type of switching device.
It’s only getting worse. It will never get better because we are putting more and more non-linear loads on the utility and fewer and fewer linear loads. Even our lighting today, we don’t use incandescent anymore. It’s all either LED, well, we used to do fluorescent, but LED is a horrific offender for harmonics.
So, and I hate to pick on that technology because. They all really are. Um, so a solar inverter, a wind turbine converter, uh, a UPS, any type of [00:05:00]device is going to introduce more harmonic content into the grid. So you got the issue where the device itself has harmonic content, couple to a grid that’s getting more and more harmonic content already on it.
So the situation is definitely getting more and more exacerbated.
Allen Hall: So some of those harmonics have really significant consequences. Uh, if you go to podge LLC on YouTube, you can watch some of the discussion there and walk through the equations about what harmonics can do to equipment on generators. Up in the the wind turbines, you can actually damage some of the Y connections on those, uh, defi generators.
It can causes all kinds of problems. And I know one of the issues that’s, and it’s being sussed out right now, so we’re talking about it live as it’s happening, is, uh, they’re seeing transients come from the line back up to, to the turbine and are causing problems to the electronics. Straight harmonics.
And the same thing coming [00:06:00] out of some of the turbines is the harmonics can be strong. And in one of your videos you talked about what kind of damage you can do with a transformer if you have harmonics that are significant enough. It’s, it’s surprising. How you can shorten the life of a transformer
Joseph Chacon: correct, or any magnetic circuit, uh, generators, motors, transformers, anything that’s going to take, uh, electrical conversions to magnetic conversions and back or vice versa, any type of thing like that.
Uh, they cause extreme dielectric stress and extreme temperature changes. Um, and both of ’em are damaging. To devices like transformers, motors, generators, et cetera.
Allen Hall: Yeah, because transformers and all that sort of magnetic equipment is designed to work around a core frequency. Typically 50 hertz or 60 hertz, depending on where in the world you are.
When you put other frequency components on that equipment, it’s not designed to do that. So that turns into a lot of heat a lot of times, [00:07:00] and then you over temp or shorten a lifetime of. Transformers on the pads and up tower in some cases that don’t. If you have a failure like that, uh, at a wind farm, I saw it most recently, uh, a couple of weeks ago, where they’re replacing transformers, like, wow, it’s only been there a year or two.
That shouldn’t happen. There are other, so those kind of failures, unless you’re paying attention, are just gonna repeat, right? Because replacing a. Pad transformer with another pad, transformer doesn’t remove the source of the problem. It just puts in another fuse in the circuit.
Joseph Chacon: Correct. And you know, let’s say you put it in, in pick a year, January of 2015, and your harmonic content from utility can change over time.
So many times it’s worth just taking a look at it. Um, in one of the videos you talked about. I promoted a [00:08:00] Fluke 1777 power quality analyzer tool that I use, and I rent that tool out to people that are wanting to do a study. Uh, and that’s an economical way to do a study. Um, the technician or engineer or whoever puts that in does not necessarily need to know a lot about harmonics to set that up.
Uh, you’re going to be putting in either three or four cts, depending upon whether you’re a four wire or a three wire system. Then connections to your bus for voltage, and then you turn the fluke on and you verify that your currents are going in the right direction. So in Phase A current, it’s phase A voltage, and you start a session and then you mail it back to me and I’ll give you the report.
Um, and it does a lot more than just harmonics. Uh, and I basically, I run an IEEE five 19 report. It does sags swells, it does super harmonics. It does intra harmonics. Super harmonics [00:09:00] are harmonics that are higher than 50, um, 50 times the fundamental. So that’s 50 times 60, uh, for 60 hertz people, or 50 times 50 for 50 hertz people.
And you, you mentioned Alan, that Transformers motors are designed for a certain frequency. Um, if you take a motor or a transformer and look at it, it’s gonna tell you the frequency. Sometimes it’s dual rate at 50 or 60. Um, but the engineer that designed that transformer motor is gonna take certain things into account related to the magnetic side to make sure that it’s able to operate for that broad frequency range.
Low frequencies are quite bad. In fact, as you get towards dc DC you can’t use magnetic circuits as a rule. I mean, there’s ways to make DC motors and things like that. And then as you get to tire frequencies, um. Then like 400 hertz is a common in aviation, you know, it’s specifically designed for that frequency.
So when you introduce [00:10:00] even small amounts, it could wreak havoc
Joel Saxum: over time. So a question for you, just I we talking, IEE here. I. Do you get into, this is like a, as a, as a podge LLC thing. Do you get into more of these studies at the development stage, or is it once they are deployed and having problems, when do they call?
Joe,
Joseph Chacon: you know that, that’s a very, very good question, Joel. Um, I do both. Uh, so if you, there’s a fixed installation. I could come in and put up the Fluke 1777 and conduct that study for that person or the company, or they could do it themselves and just, uh, FedEx or UPS me back the equipment and I could interpret the data.
If you’re doing a new installation, I use a software called Easy Power. There’s others, uh, SKM, etap. Um, you know, if you ask me what type of phone I use, I’ll tell you I got an Android. Why do I have an Android? Because that’s what I’m comfortable with. That’s what I use. I’m not [00:11:00] opposed to Apple or anything like that.
Why do I use Easy Power? Because that’s what I use. I mean, it’s, you get comfortable with what you use. Um, 20 years ago I used SKM. But easy power. And there’s a video on that YouTube series I mentioned about how to use easy power to do IEEE five 19 harmonic studies before you even put it in. Um, so that can be done as wealth.
I. And I can model it with easy power after the fact too. Uh, but Fluke makes it so easy. It’s just hook up 6, 7, 8, 9 leads, whatever, click record, come back a few hours later and populates the report. Then when you want to talk about the fix, then I might have to use Easy Power to help with. Do you want a, so there’s lots of fixes and, and I hope we get to talking about some of the fixes here in a minute.
Joel Saxum: That, that’s what I wanted to dive into next. ’cause I’m thinking, okay, earlier we talked, uh, RCA, how these, you know, what’s happening here And my mind immediately [00:12:00] goes to, and, and everybody that’s listening here knows I’m not an electrical engineer. Uh, like, not nothing nuts whatsoever. You know, like I, I, I put uh, KC lights on a truck once and almost burnt it down.
So that’s not my, that’s not my thing, but in my mind, I, this goes through this, this unstable grid with a lot of frequency. So I go like, okay, is it a grid macro problem? Like, do we need to have more flywheel type technology on the grid to even these things out? And I’m thinking about like, I’m in Texas here, right?
So there’s all kinds of renewables, all kinds of, you know, up, down, up, down, up, down. We talk about duck curves and we can look at a graph. Yeah, that’s the entire grid. But when you talk about at the wind farm or solar farm level, there’s so much differing load. And now we’re adding batteries and we’re adding data centers and all that stuff.
So there’s, there’s multiple. Entry points, I think, to solve this. And one of ’em is, is like, is is Joe Shahan standing in front of Ercot and telling them how to fix their problems at a macro level. But what we, but I think what we wanna dive into here is there’s also filters and other [00:13:00] fixes from, you know, the abbs and the Siemens and the Schneiders of the world that can fix things at a local level.
So what are some of these problems that you see and then fixes that you prescribe to solve those problems?
Joseph Chacon: I must clarify, it’s not a utility problem unless the utility is using massive amounts of renewable energy. Um, with that said, though, uh, whoever makes the wind turbine or whatever the asset is, you’re gonna be required for the point of interconnect to do that IEEE five 19 study.
Um, what causes the problem is on the load side. Because you have the most classic case of this is a six pulse, uh, rectifier on the front end of a variable frequency drive. Um, before the advent of that, people would just put across the line starters or across the line contactors to turn on [00:14:00] a motor. And a motor is a very linear device.
The only issue you might have with that are dips and swells. Uh, or mostly dips for that matter. But when you put a variable frequency drive on there, which is a wonderful, wonderful device, it gives you absolute control over that motor, and you wanna put it in all day, every day. But when you put it in, you’re gonna wanna put a line reactor in front of it.
And if your VFD is here and your motor is so many feet away from your VFD, you’re gonna wanna put in different types of things as well. And those could be DVDT filters. Our sway filters ultimately. And I mean, sometimes you can just do a basic choke, but you’re gonna usually look at A-D-V-D-T filter or a sway filter between those two devices.
So those are what you’re gonna do at the source for where you are creating your harmonic content that gets reflected back up onto the utility. So those are very simple things to do that [00:15:00] in my opinion, are no-brainers. And also use shielded cabling. Um. I, I preach this a lot between your VFD and your motor use shielded cabling.
Um, now let’s talk about if you’ve got all this in place and you still have massive amounts of harmonic content, what do you do? I’m in love with the active harmonic filter. This is the best thing since sliced bread. And I don’t wanna oversell it because, uh, uh, my wife says, you talk about it so much that you make me think you’re overselling it and I don’t want it.
That’s not what I’m trying to do here. But there’s tons of people, uh, companies that make an active harmonic filter and that has the capability at the point of common coupling of completely neutralizing your harmonic content. And this is the part that I like the most. Power factor correction. So power factor is, uh, just basically a ratio of, uh, [00:16:00] real power and reactive power.
Um, you want it to be as close to unity as possible, and that’s what the utility likes. So another side effect of excessive harmonic content is also lower power factor, um, when you accurately measure it. So an active harmonic filter. Um, it’s kinda like, I forget which law. I think it’s Newton’s third law for every force, there’s an equal and opposite force to go with it.
So if I just push that there, I’m not pushing back on it. Right? So if you have a, let’s say you have, I don’t know, 500 hertz of harmonic content that’s constantly being injected. An active harmonic filter will come in and basically do that. It’ll also do it for other frequencies all at the same time, completely counseling them out.
It really is a, a wonderful, wonderful device. And you don’t have to put it in series with anything. You put it in shunt and that means you could get close to [00:17:00] your point of common coupling. So on. So a point of common coupling. It, you could be def you could define it anywhere, but if you were gonna put this in, uh, let’s say at a a, a solar plant.
You could put this in at the output of the central inverter, or if you got a string of series, um, a series of string inverters, you could put it at the switchboard there as well. Um, and it’ll neutralize the harmonic content that’s there and even downstream as you get further and further away from ect Harmonic filter.
Your THDV, that’s total harmonic distortion, voltage, and a little bit of THDI, total harmonic distortion. Current goes down as well, but at the point of common coupling, you are putting the cadis on that and squashing it. It’s a pretty cool device and I. I don’t sell them, but I help specify them.
Joel Saxum: So it’s like, it’s the, it’s the ultimate [00:18:00] noise canceling headphone for BOP.
Joseph Chacon: Yes. Perfect. That’s exactly the best analogy. I love that.
Joel Saxum: So you go on Amazon, you buy a set of BS seven fifties, and you put ’em over the cable. Right. Then it’s good.
Joseph Chacon: Very,
Joel Saxum: very
Joseph Chacon: similar technology. Yes. I, I love the analogy. I love the analogy.
Allen Hall: Yeah. But it’s magic because 20 years ago you really couldn’t do that.
Or if you wanted to, it was super expensive and. If the prices come down, they’re still expensive, but you’re trying to eliminate a more complex problem that you didn’t necessarily create, right? So a lot of these harmonics. Or coming out of equipment that probably did not really meet the spec to begin with, and you’re just trying to find an ultimate solution that gets the plant running again.
And that’s the key here. It’s gonna save you a tremendous amount of time and effort if you can use active suppression instead of trying to fix the a hundred inverters that are creating this problem. And,
Joel Saxum: and that’s
Allen Hall: the one
Joel Saxum: thing I want to touch on there, like, if, if, if this isn’t solved or if this is an issue and [00:19:00] you don’t use a certain fix.
Failures, the what are the components that will
Joseph Chacon: fail any and everything. I, I was, uh, gosh, I did a presentation of harmonics a couple of days ago, and I used the Bugs Bunny analogy of the gremlin in the airplane. Uh, so in the 1940s during World War ii, many of the pilots would say, we have gremlins in our system.
Um. Gremlins are kind of like harmonics. They just show up in all types of different places, even even on mechanical devices, uh, related to bearings and other things. Um, they, it just shows power supplies can start going, motor bearings can start falling. All types of things can start failing. So
Allen Hall: let’s talk about that.
There are a number of main bearings that are failing in wind turbines today that look like they have electrical discharge damage. And the, everybody who’s designing these systems, these wind turbines is pretty smart, right? There’s, there’s a lot of engineering that goes into a [00:20:00] wind turbine, but when you have undesirable harmonics, regardless of where they come from, can be from a SU piece of supplied equipment that those harmonics can show up on.
Mechanical devices like bearings, you can actually pick up harmonics physically from discharge, you’ll see discharges to bearings and. Uh, drive shafts all the things you wouldn’t expect. But here’s the one thing I wanted to talk to you about, Joe. Can you, can you kinda physically see like, oh, that’s an electrical discharge, or, oh, that’s a mechanical failure.
Are there differences between those two when it comes to mechanical failures from harmonics?
Joseph Chacon: In cases like that, that’s where you wanna pull, pull in a holistic RCA approach. Uh, kinda like the gentleman John we’ve been talking about before. Um, John is a great systems engineer and he would help isolate electrical, mechanical, environmental, things like that, uh, and look at the contributing factors [00:21:00] that come in to producing all of those things.
The answer is yes, it could. Um, but not every time. And it takes, uh, a certain amount of surgical precision to diagnose the root causes or combination of root causes.
Allen Hall: Yeah, it’s one of those Sherlock Holmes, uh, quotes, right? Once you’ve eliminated the impossible, everything else is. Possible. What is that?
What is that saying guys? It’s probable, there you go. Right It where you’ve, on the mechanical side, it seems like we’ve eliminated a lot of mechanical probabilities of, it could be something in manufacturing, it should be something in tempering, it should be something in coatings. And now we’re going down that rabbit hole of, I wonder if this is electrical discharge.
I wonder if the brushes are working. Do we need to install brushes? Do we need to add more grounding? In the towers to get rid of some of these or provide another path for the harmonics to go through. It’s a complex problem. But Joe, if they’re not bringing someone like you into help look at this problem, they’re not gonna solve it just by [00:22:00]
Joseph Chacon: eyeballing it.
Right? Right. And then finally, the most important consideration of all of this is, is economics. Um, and fin finance. Um, sometimes living with the devil, you know, is better. Then the angel, you don’t know. And uh, you notice I switched that up. Yeah. Everything has to have an ROI in a business case, and you can come in and solve this and probabilistically reduce all failures to six seven Sigma.
Um, but at what cost? Um, so what I try to do is help customers really dig into it electrically. And if, and if you got mechanical devices that are failing, then you’re gonna wanna look at it holistically. Um. In, in the case of solar and things like that, you know, you don’t have a lot of moving parts. Wind turbine’s a little bit more complicated.
Um, but at a facility, um, where you have motors and drives and things like that, um, it, it doesn’t always have [00:23:00] to be electrical or mechanical. Um, I, I became a thermal engineer over the, over the last few years, not because I liked thermodynamics. Because I had to keep my electronics cool and it was a discipline that I had to, to really get familiar with.
Um, the things related to bearings and other stuff like that. I’ve known some phenomenal bearing people, loads people through the years. That stuff I don’t understand. When you bring in a good system engineer and you’re able to holistically parse it out, uh, that, that would be the way to go on those things.
Joel Saxum: Absolutely. I like part of this conversation here, Joe, is that, um, okay, so this is, this resonates with Alan and I because we are talking with lightning protection people every day, right? Like, Hey, I have this issue, have this issue. There’s a specific fix or, or a, a prescribed fix for a lot of different things that can happen.
But it all needs to be based in a business case. If the business case doesn’t make sense. Or you can’t present a decent business [00:24:00] case to someone, you might as well just get off the phone. I, and, and I think that the wind industry really needs that, uh, renewables industry in general, but the wind industry really needs that if we’re trying to ’cause the goal, one of the goals of the, the uptime podcast here is to lower the, the LCOE if we can help make wind turbine or wind energy more competitive across the globe.
Beautiful. So the, the fact that you’re approaching business as business case forward, I really like to hear that.
Joseph Chacon: That’s good feedback. I like that.
Allen Hall: So Joe, I know we could go on all day and if you let me, I will. Uh, so we’re, we’re gonna have to invite you back because I think as Joel and I learn more about some of these harmonic problems that exist in turbines and, and also.
On the line, uh, we want to talk to you about possible solutions, what you can do about it, how to address it, even how to suss it out, diagnose it
Joseph Chacon: related to, to lightning. Uh, I’m sure all the time you’re constantly looking at, did the utility cause this, did the device cause this, or did lightning cause [00:25:00] this?
So bringing that harmonic aspect in and utility power, quality in general. Harmonics is just a subset of the overall power quality. Um. It, it definitely does help differentiate things from something happened electrically. What was it? You know, that, that, that level of knowledge I think goes a long way.
Allen Hall: Yeah, it sure does. So Joe, how do people get a hold of you if they need to do a harmonic analysis or just take a, a kind of a holistic look at what’s happening electrically in their turbines or in their solar facilities? My
Joseph Chacon: email is pretty easy. It’s josephchacon@padge.org. Um, my website is padge.org as well.
Um, I encourage people to check out the YouTube videos because that’s to demystify harmonics a lot and, uh, educate people. Uh, my goal is if people and technicians and engineers are educated. It helps them become better for [00:26:00] their companies. And, uh, you know, I do like making a buck, but more than that, I like seeing people succeed.
And, um, I have a lot of people in various industries, uh, not just renewables. Um, I wanna give them the tools to be able to do what’s best for their companies. And that’s what. Helps me sleep good at night is is doing that in education.
Allen Hall: So check out Joe’s website, it’s spelled padge.org and you can also check out Joe’s YouTube channel.
Same thing, Padge LLC. Just put into YouTube and it’ll come up. You can watch some of those videos on harmonics. Very interesting stuff, Joe. Appreciate you actually putting that up on the internet. Uh, it’s gonna help a lot of people. So Joe, thank you so much for being with us today. And yeah, we’ll talk soon.
Thank you, Allen. Thank you, Joel.
https://weatherguardwind.com/padge-llc-harmonics/
Renewable Energy
Pardalote Studies Australian Blade Erosion and Heat Fatigue
Pardalote Studies Australian Blade Erosion and Heat Fatigue
Rosemary Barnes, CEO and founder of Pardalote Consulting, joins to discuss their new grant-funded study of blade erosion and heat fatigue in Australia.
Sign up now for Uptime Tech News, our weekly newsletter on all things wind technology. This episode is sponsored by Weather Guard Lightning Tech. Learn more about Weather Guard’s StrikeTape Wind Turbine LPS retrofit. Follow the show on YouTube, Linkedin and visit Weather Guard on the web. And subscribe to Rosemary’s “Engineering with Rosie” YouTube channel here. Have a question we can answer on the show? Email us!
Welcome to Uptime Spotlight, shining light on wind energy’s brightest innovators. This is the progress powering tomorrow
Allen Hall 2025: Well, Rosemary, welcome back to the show.
Rosemary Barnes: Thanks, Allen. Great to be here. For, it’s been a while since we did one of these one-on-one episodes, like a, yeah, a proper, proper guest.
Allen Hall 2025: Well, this is kind of a celebratory episode because your company, Pardalote Consulting, has been awarded, uh, some funding from the Australian Capital Territory’s government for the Energy Innovation Fund.
Rosemary Barnes: It’s a really good program that the ACT government has to try and get energy innovation In the state. It’s not a state actually, it’s technically a territory. Little more than just Canberra, the city. Uh, but there are actually quite a few, like, really interesting energy-related companies here, partly ’cause of the, the fund I think helps, but also just tracing back like, [00:01:00] uh, y- you know, in the 20-teens, Australia had a really conservative government that hated renewable energy, and the ACT government had a commitment at that time to 100%, um, 100% renewable electricity for the, the government.
And that was one of the only programs that was resulting in a lot of, um, you know, clean energy projects being built, and one of the conditions that they put on that, uh, for people that would win PPAs with the ACT was that you had to have your headquarters in Canberra. So we’ve actually got quite a few, quite a few really cool, innovative companies out of here.
Um, like Neoen’s headquarters here. Windlab, uh, yeah, was, was founded here and still has a lot of people here. Pardalote obviously, and you know, a few other companies as well. So despite it being a small city of like, I don’t know, maybe it’s up to 400,000 or something people by now, um, yeah, there is actually quite a lot going on here for energy.
Allen Hall 2025: And the Energy Innovation Fund is funded by the wind and solar operators in the area, and your particular [00:02:00] effort has really global consequences. You’re focusing on two areas involving how wind turbines survive Australia, but more, uh, of relevance is to just really tough conditions which exist not just in Australia but around the world.
What two areas are you going to focus on?
Rosemary Barnes: Yeah. So the two focus areas are leading edge erosion and high temperature fatigue, which we can probably get into the definitions of those in a minute. But basically my, um– what led me to wanna have a project like this was that when I moved back to Australia in 2021, I– and I started working in O&M, uh, I noticed that the wind turbines that I would look at, the blades that I would look at here behaved really differently to the ones that I worked with overseas.
You know, es- especially with leading edge erosion, like often I would be doing a condition assessment of a, you know, a new wind farm. Um, might only have been operating for, you know, two years. That’s a pretty common time for people to get in and do a condition assessment [00:03:00] because their warranty period is about to end and they wanna, you know, make sure that everything is okay.
Um, and I would just notice that often, like 90, 100% of blades would already have bad erosion after just a couple of years, which is super-duper fast. And then there are some tools available to check, um, like what kind of erosion are you likely to experience on your site. Like is it a higher severity erosion site or a, a low severity one?
Um, and you basically, you know, the status quo globally is to just look at the annual rainfall, um, and the tip speed. And if you’ve got, you know, high for both of those, that’s a bad erosion site. And if you’ve got low for both of those, it’s a, a low erosion site. But when I plotted out the wind farms that I knew had really bad erosion problems onto, you know, a chart with those two axes, I just saw a random distribution of dots.
You know? Like, this was not– uh, this had no predictive value for Australian wind farms. And so that led me to believe that, okay, um, you know, things are a bit [00:04:00] different here. Makes sense, you know, most of the knowledge that we have about how wind turbines operate, it’s been developed and validated mostly in Northern Europe.
You know? Like it’s, it’s Denmark and the surrounding countries that had, like, the bulk of the early wind energy. First few decades of knowledge were, you know, were mostly there. Of course, there were some other, um, places that had wind turbines, but, you know, most of the The OEMs have been operating for decades, came from Denmark.
And I know when I lived in Denmark, the rain there is very different to the rain in Australia. So in Denmark, it’s basically always raining, right? Like, it’s just… Like, even if it’s not raining, you’re still gonna get wet when you go outside ’cause it’s just, like, the air has this just amazing ability to just hold onto moisture.
Um, but it’s very, very gentle. But, you know, over an entire year of most days having gentle rain, that adds up to a lot. Whereas in Australia, and especially if you go, like, north to Queensland, it rarely rains. It’s mostly just dry, and when it [00:05:00] does rain, it’s like a tap turns on, and I, I swear you will get bruised from the rain droplets hitting your skin.
You know, they just have so much energy in them. So I think that that i- you know, when you look at just the overall rainfall, you really hide something important about how erosion, um, can progress. Then, um, there’s other places in Australia that have very different characteristics. Again, they don’t have that kind of really intense rain but, you know, some of those sites are also having really bad erosion.
And so it just occurred to me, I did a lot of research, you know, into what’s going on and, you know, the academics are studying erosion a whole lot, and they’ve got, you know, a lot of standardized tests and, you know, products are developed according to these standardized tests. But the standardized tests don’t actually resemble reality, and especially they don’t resemble reality in Australia.
And so my client started asking me, “Okay, you know, the products that we have are, are terrible. We have to replace them every couple of years. It’s, um, causing big problems with also [00:06:00] the amount of energy that you’re losing.” One of the types of, um, leading-edge erosion or leading-edge problems that we have in Australia is that the, the coatings tend to peel off and make these, like, big flakes which will just massively disrupt the airflow, can cause y- you know, at least a few percent AEP loss, and maybe up to five.
And even worse than the AEP loss is the revenue loss because it affects it most at, you know, lower wind speeds. Um, you get a bigger hit than at rated wind speeds. So there’s a variety of problems going on with leading edges in Australia, which mean that I, I basically… My clients would ask, “What product should we put on to prevent having to, you know, constantly replace this?”
‘Cause it costs, like- you know, 30, $40,000 per turbine to replace the protection, not to mention, you know, one or two days of downtime. It’s expensive, and I basically, I didn’t have a good answer for them. What, what product should they put on? I don’t know. No, we, we don’t know. One, we don’t know what the [00:07:00] specific, um, characteristics are that are…
what the specific local environment, local conditions are that are accelerating leading-edge erosion, one. And two, all of the products tend to be tested around this, you know, there’s this protocol that academics have come up with, and they’ve kind of like assumed that this is representative of how things behave in the field, and it’s– I don’t think it’s particularly true anyway, but it’s especially not true in Australia.
There are a few companies that are testing to different standards. Um, definitely applaud them. But without knowing wha- what are the conditions truly like in Australia, uh, it’s really hard to advise, like, what kind of tests should you be demanding from a product you’re considering to be sure that you’re gonna put it on and not gonna be replacing it again in two years.
Allen Hall 2025: Because that’s really the trouble in Australia is when you get offered products They have been tested generally in somewhere in Europe and maybe in the United States, and then when they go to [00:08:00] Australia, it’s really unknown as to how those products will do, which is a huge risk for the Australian wind market as to what to choose, how to choose, is it– what’s real in terms of test data.
So now you’re gonna go out and do what? Are you gonna put sensors out by the wind farms? Are you gonna try to do more of a statistical summary of the actual environment around wind farms using existing data? What’s the approach here?
Rosemary Barnes: It’s all of the above, but the part that is supported by the grant is that we’re gonna have enough money to be able to buy some scientific-grade sensors and put them on, um, a sample of Australian wind farms.
So we’re gonna be looking at a lot more characteristics about the rain than simply is it raining now, you know, how many millimeters per hour. We’re also gonna be investigating, you know, every kind of characteristic of, of that, um, of that rain, um, including, yeah, like the, the energy that’s in it, for example.
A, a bunch of stuff. I won’t get into every single [00:09:00] parameter. Um, and you know, other things as well, like measuring UV, solar radiation, um, particles, because, you know, in Australia we have a lot of dirt roads, which I know is very common in wind farms around the world, but Australian dirt roa- roads are always dry and dusty, like 99% of the time, so that’s one of the things that y- you know, maybe that’s causing a difference.
Um, so basically putting sensors all over a bunch of wind turbines and then monitoring the erosion, um, a combination of some real-time monitoring and also looking at inspection, um, drone inspection images annually. We also have a- an option where we’ll just be using SCADA data and inspection images, so that’s like a lower cost version where we can combine that with the findings from the scientific-grade instrumented turbines to build up a picture of what types of conditions lead to accelerated erosion.[00:10:00]
Allen Hall 2025: So the SCADA data will, will have some information inside of it, you think, that, uh, will correlate to the weather outside?
Rosemary Barnes: It has some Additionally, we can look up, um, you know, just the weather data, like how many millimeters fell during which 15-minute interval throughout the day, what was the temperature.
SCADA will tell us also what the temperature was, um, what the speed of the turbine was, so you can calculate the tip speed, ’cause that’s an important thing. Um, yeah, so it’s, it’s two, it’s two tiers of data collection. The scientific grade sensors, as you can imagine, are, are really expensive and y- you know, the, the grant project has contributed a, a lot of funding, um, but it’s not enough to put those, yeah, put a little mini lab on top of every turbine across Australia, obviously.
So that we’re using s- doing selectively, and then we can increase the number of wind farms that are included in the study by just doing this, um, cheaper version of the SCADA [00:11:00] plus, uh, weather data that’s available.
Allen Hall 2025: So what are some of the risks on the temperature side for all the high-temperature regions of Australia that have wind turbines?
Clearly it’s generally warmer in Australia than it is in, in Scandinavia and Northern Europe. What kind of temperatures are we talking about on the ground?
Rosemary Barnes: Uh, well, temperatures here can get pretty close to 50 degrees. Um, and if you’ve ever been inside a wind turbine blade on a, even a mildly hot day, you’ll know that the temperature inside a wind turbine, and especially inside the blade, is much hotter than what it is, uh, what the ambient temperature is.
So this project is one– I’ve actually been talking about this project for, yeah, like over 10 years now. Ever since I started, I moved to Denmark, started working for a wind turbine manufacturer, I had done– I had just finished doing my PhD on composite materials, structural design, and analysis. So, um, yeah, very, very familiar with, [00:12:00] you know, how composite materials work and, in particular, the effect that temperature has on them.
I mean, like most materials, when composites get warmer, they get softer, and that is really important for a w- a wind turbine blade. You know, if it gets, um, less stiff, then you’re gonna get a lot more strain, and that is going to affect your fatigue behavior. Y- you know, fatigue is just the application of a little bit of, a small amount of strain.
It’s not gonna cause damage, but when you apply it millions, tens of millions of times, like you do in a, o- over a wind turbine’s operate, um, operating lifetime, then that builds up. And, you know, wind turbine blades are a very fatigue-driven design. Um, it’s one of the most important things to consider when you’re designing a wind turbine blade.
And so when I got to Denmark and I learned how materials are qualified and how the qualification is treated in the certification process, I just realized it’s not particularly conservative, and also that some of the assumptions that are made that [00:13:00] wo- again, they worked really well in more moderate climates where wind turbines have had most of their developmental history.
You know, it’s not such a big deal there if you test at room temperature. Your wind turbine blade is spending most of its operating lifetime at room temperature or below. It’s, it’s rarely, you know, above 30 degrees in Denmark and most of Northern Europe and, you know, also a lot of, um, a lot of America, not, not all of it But, um, in Australia it has just extended periods above that temperature and even exceeding the temperature where, you know, wind turbines have an operating limit and after that they will shut down.
But the operating limits are based on ambient temperature. It’s not based on what’s the temperature in the laminate, which is what really matters for blade lifetime. So anyway, I’ve been obsessed, like honestly obsessed about this issue for 10 years. Talked about it with anybody who would listen . But then when I started working in O&M in [00:14:00] Australia and I started seeing some wind farms with an abnormal number of cracks early…
again, early in their lifetime, you know, I think one of the wind farms I was looking at was maybe three years old or four at the time. I think it was three actually, and had a lot of cracks, and I looked at a few years in a row and it was more and more cracks every year and I’m like, “Oof, this really looks like end of life fatigue behavior.”
A- actually it’s not, y- you know, there’s this concept of a bathtub curve where, um, when you’re looking at failures in components, in, in anything, not just in, um, wind turbine blades, but you know, like you’d start– it’s called a bathtub because, you know, when it starts operating, you’ll get quite a lot of failures.
Anything big, any manufacturing defects or anything are gonna cause failures quite fast, and that kind of drops off over time as all of those, uh, get addressed. And then you have, you know, the bulk of your operating life, it’s like pretty low level, pretty, pretty constant for a long time and then as you get towards the end of the [00:15:00] life, you start to see failure rates rise up again.
That’s your fatigue failures, your end of life fatigue failures. And so when I saw the same types of cracks more and more each year, I’m like, “This looks like, you know, the foot end of the bathtub, not the head end.” And, uh, it made me worried and I’ve now seen that across a few wind farms in Australia at, um, hotter places.
There’s a few blade types that are more prone to it than others, but at this point it’s still a suspicion that that’s what’s going on. I mean, a suspicion backed by a lot of, a lot of theory and knowledge of how the certification process works. But this project now we’ve got some funding to actually go put some sensors onto wind turbines, actually learn what the temperatures are in the blades throughout the whole laminate, um, not just the, you know, on the outside surface or not just the ambient temperature, but actually, you know, develop a temperature gradient across the whole, um, the whole laminate in the blade shell.
Um, and [00:16:00] then we’re going to be doing a bunch of modeling basically to look at what is the effect of these different temperatures that blades are really seeing and how much would we expect to… that to decrease a lifetime. And then we should also be able to say, you know, if you have this issue in your wind farm, you might be able to change your operation a little bit and extend your lifetime a lot.
Because this one, it’s real– like, in contrast to leading edge erosion, leading edge erosion is just, it’s, you know, every wind turbine has it to a certain extent, and it, it’s always there, but it’s a relatively minor cost to fix it. You know, like it sounds like a lot, like 30, $40,000 per wind turbine, but, um, you know, compared to if you’ve got to replace every blade across your fleet because they’re all, you know, at the end of their life after five years, you know, that’s obviously shocking.
And, you know, that’s a bad example, but even in a y- you know, like a less extreme example, maybe [00:17:00] after 15 years you have to do a, you know, a f- a fleet-wide campaign to strengthen blades or something. It’s, you know, m- many millions of dollars for that, and so it c- could make sense to be able to learn, okay, what, what hours of operation should we be avoiding?
Additionally, because when it’s super-duper hot in Australia, usually you’ve got heaps of solar power and the electricity price is not that high. So I, I think that there– and I don’t, obviously, before we’ve done the project, I don’t know what the threshold is. But in both cases, we will be aiming to improve the knowledge of how you can operate to avoid these periods of accelerated damage.
Allen Hall 2025: Do you think you’re seeing more fatigue-like damage due to the blades operating when it’s hot or not operating when it’s hot, with maybe less airflow around the blade and maybe less cooling going on is just a temperature soak At rest? [00:18:00]
Rosemary Barnes: Yeah. It’s interesting because the temperature is higher if it’s not rotating, um, because you get a whole lot of, um, convective heat, heat transfer when the turbine is operating.
So your temperatures are not gonna get as hot when operating as when they’re standing still. However, if it’s standing still, they’re only very lightly loaded. Like, yes, they’re gonna get, um, blown by, by gusts and, um, have a little bit of bending, but it’s, it’s very, very small compared to, uh, if it is y- you know, operational loads.
Uh, assuming that you’re not in the middle of a s- a storm. But yeah, a storm probably doesn’t come with 50 degrees temperatures.
Allen Hall 2025: And what part of the blade is susceptible to these higher temperatures? Is it the resin? Is it the fiberglass or carbon fiber? Or is it the, the glue, the bond joints? What part are you focused on?
Rosemary Barnes: The resin is the main part that I’m focused on. It gl- it could be an issue for glue too, actually. I haven’t even looked into what the, um, yeah, temperature assumptions are with, with glue, with [00:19:00] bond lines. But the failures that I’m seeing in the field are not, are not bond line issues. It’s, it’s, um, a laminate problem.
Allen Hall 2025: What about balsa and foam inside of the blade? Are they affected by the temperatures or are they pretty temperature stable?
Rosemary Barnes: I don’t think they’re affected at these kinds of temperatures, no. They, they don’t really do much actually. The, the core materials, like it, it is very important that they’re, that they’re there, but their job is really to keep the fiberglass separated from its- itself to make it stiffer.
So, um, yeah, that’s, that’s unlikely to be a, a major source of problems.
Allen Hall 2025: So this study is gonna work over about three years, and you have a number of wind farms that are participating. Are you looking for more wind farms to participate in Australia?
Rosemary Barnes: Yeah. Yeah, definitely. I mean, we can, um, have as many as, as people want to join.
We’ve got quite a good selection so far. Definitely can always welcome more. A, a bit limited in how many can get the really, um, good sensor [00:20:00]package, because the grant funding is a, you know, a certain amount, and that’s paying the bulk of those sensors. So, um, those spots are limited. So if anybody wants to really zone in on what is specifically causing erosion on their site, you know, if you know that you have got leading edge protection that is not good enough and you have to replace it soon, but you don’t know what to replace it with, then, you know, that would be the kind of wind farm that might want to consider, yeah, joining this and, um, you know, getting these sensors on their, um…
We’re putting them on top of the nacelles, most of them. Um, yeah, so that would be a good match then. Um, and then, yeah, for the ones that are doing the SCADA data and, um, weather data- There’s not such a, a hard limit on how many we can have join like that. So yeah, we can have more, more like that.
Allen Hall 2025: In the temperature fatigue effort, i- is that still looking for participants or are there particular wind turbine types or manufacturers that you’re [00:21:00] looking for to participate?
Rosemary Barnes: Yeah, I think, um, I, I mean yes, we can have more of those. That’s a simpler, a, a simpler issue as well. The sensors are not so expensive and, um, it’s, yeah, it’s a, it’s a simpler project to join that one. We only need, you know, a couple of turbines per site, so it won’t be such a, uh, an involved process to get everything up on into the turbines.
And in terms of who might like to join that, I would say anybody that is in a really hot area where, you know, where they see a lot of days over 30 degrees, and if they see any days, you know, getting into the high 40s, then I would say that that’s worthwhile. Or even I have seen this issue in some milder sites, um, yeah, depending on the, on the blade type as well.
It is more common with polyester resins. They have a, a lower op- uh, maximum operating temperature than epoxy resins. But then also just anybody that has noticed just, hey, [00:22:00] we’ve got a lot of cracks, and it seems like we’re getting more and more cracks every year, which to be honest, can be hard to keep track of if you’re…
If you’ve got a full service agreement, uh, you know, an OEM managing your wind farm The early signs of this are gonna be category one and category two cracks. They’re not in exactly the same location. It’s, you know, it’s a tricky one. Normally, if you’re looking at a serial issue, then you’re going to have, uh, well, you know, your ideal pattern for a serial issue is the exact same thing happening over and over again.
And so it is harder to pull this out. It also really would be very rare for it to be happening in the first two years or three years, whatever your serial defect liability period is. So it’s quite hard. But, um, another group of wind farms that might like to consider it is if you know that in, you know, a certain number of years you have to renegotiate your service agreement or, you know, it ends and you might have to take over yourself, then this’ll be a really good way for you to [00:23:00] understand, you know, have I got a ticking time bomb here?
Um, because it’s not something that you’re gonna be aware of if you haven’t been, you know, doing some really, really in-depth shadow, shadow monitoring of your blades, you know, running your own inspections and looking at every single damage, not just category three, four, five, but lower ones. So yeah, I mean, there’s a, a wide variety of people that, that could be interested in joining.
Allen Hall 2025: Are you expecting a number of manufacturers that make leading-edge protection or involved in resin creation, some– there’s a number of resin companies and a variety of resins that are used globally, sort of interchangeably at times. Are you expecting some of those companies to participate in this effort just to learn about the Australian environment?
Rosemary Barnes: I think it would be a good opportunity to test out some products and see how they behave in the Australian context. I think that that would be a really good selling point, but I, I have to say that most of the companies doing that sort of thing that wanna enter Australia, they don’t [00:24:00] really consider…
Like, from the perspective of wind farm owners in Australia, if you can’t show us wind farms in Australia where this has worked and, you know, show us a before or after, you know, the old LEP lasted Two years and our LEP is going on four years now with no damage. It, you know, unless you’ve got a before and after like that, you can tell us however many turbines that you’ve got installed around the world, but, um, we don’t consider it validated, y- you know?
It’s not validated for Australian conditions yet. And I do have this same discussion over and over again with, you know, not just leading edge protection, but all kinds of, um, you know, manufacturers of whatever doodads that you put on to improve a, a wind turbine. It’s so different to Australia. Things break so fast.
And I’m talking everything, you know, like vortex generators fall off and, um, yeah, like, uh, you know, bits of lightning protection systems fall off, seals just [00:25:00] crumble and disintegrate. Um, and it, you know, we’re very wary of, of new products. So I, I do– I mean, I’m thinking of it more from my client’s point of view than from the product manufacturer’s point of view.
But one thing that I wanna get out of this pro- project is to be able to answer one of the most common questions that I get is, which is, what leading edge protection should I be putting on my turbine? And for now, I don’t know. I, I know a range of products that don’t work in Australia, and not much more than that.
So, um, yeah. And it’s also, you know, Australia’s a very varied place with lots of different kinds of climate too. So it’s not gonna be like, you know, the product that works in Queensland is the same one that’s gonna work in Tasmania, which is the same one that’s gonna work in Western Australia. You know, um, so it, this project is gonna really pull out what are the site specific issues you’ve got at your site and what kinds of, um, you know, tests would we need to see a product um, perform in order to know that this [00:26:00] is gonna last on your site.
Allen Hall 2025: W- what is the outcome of this project or these two projects? Are they gonna be reports or, uh, a, a continual monitoring system that’s designed for the Australian environment? How do you see this going?
Rosemary Barnes: Yeah, so one part of it is, um, developing a way to identify periods of accelerated damage and to know not to operate during that time.
So we call it protective operation. Uh, so that would, uh, help you if, yeah, you’re trying to extend the life of something or increase the amount of time before you have to repair, then y- you know, that would be useful to have that knowledge. And it will be as simple as just an alert saying, “Hey, accelerated damage conditions.
Consider, you know, if you wanna keep on operating.” And, you know, if the price of electricity is super high at that time, they may want to push through, and if it’s low, they probably won’t want to. So that’s one thing. Um, especially, you know, as wind turbines get to their, near the end of their life. I’ve got some clients whose wind farms only have, you know, [00:27:00] maybe five years operation left.
They just simply don’t wanna repair their leading edge protection again. They just, they, they don’t wanna do that. So they would be happy to, you know, reduce operation a bit and have their turbine limp through to the end of the period. Y- you know, you want everything to wear out at once. You don’t want brand-new leading edge protection on a turbine that’s going to come down in a couple of years.
Um, so, you know, that’s, that’s one part of it. And then the other thing is, you know, turbines earlier in their lifetime, how can we optimize the maintenance schedule with leading edge erosion? Um, so, you know, like it’s a lot cheaper to, uh, replace the LEP if you get– catch it early, but then you don’t wanna be catching it too early and replacing it, you know, constantly when you, you don’t need to.
So, um, yeah, it, this, having this knowledge will enable a site-by-site operations and maintenance strategy with respect to leading edge protection. We also have some sites who are having trouble. They’ve got a full service agreement, and the OEM is [00:28:00] responsible for, um, doing the leading edge erosion repairs and protection replacement, but the owner is on the hook for paying for it.
At the other end, we’ve got people with full service agreements where technically the, um, manufacturer is supposed to be doing the leading edge protection and paying for it, but they argue about what, when does it need to be done. Because, you know, um, the operator might think if there’s no structural risk, then we don’t need to be replacing it.
And in the meantime, you’ve got turbines spinning around for years and years and years with, you know, these huge flakes of leading edge protection s- you know, causing the flow at the tip of the turbine to, to detach and to stall, and horrible aerodynamics, huge losses in power generation and revenue. And they’re having a big fight about, you know, is this necessary to do or not?
And then, you know, they’re just gonna put the exact same product on again ’cause the [00:29:00] OEMs are re- all really, really wedded to their own particular brand. It’s like, “Well, last time we had this product and it was factory applied, it lasted one year before it s- it was worse than, you know, if it wasn’t there at all.
Uh, we don’t really want you to put that one on again.” And so, you know, having the information that they need to be able to, you know, really bring data to these discussions and, you know, makes a, yeah, data not drama. That’s a, a good approach I think, um, for any kind of negotiation and especially in the case of leading edge erosion.
And then for the high temperature fatigue part of the problem, aside from, you know, just wanting to know are your blades aging, should you be looking at remediation action or changing the operation, the other really big key thing is, uh, you might need to have a fight with y- your OEM about if this turbine has been designed and operated correctly.
And so then having the data from this, um, project is going to give you the information that you need to come into that [00:30:00] argument with, again, the data not the drama. Um, and to, you know, in- increase your chances of succeeding in that kind of really tricky negotiation.
Allen Hall 2025: So if you’re an OEM or a manufacturer of equipment, an ISP, an operator, pretty much all aspects of wind operations, you probably ought to be getting a hold of Pardalote Consulting and Rosemary to talk about the opportunity to participate in this study.
How do people get ahold of you to, to do that?
Rosemary Barnes: People can go to our website, pardaloteconsulting.com, and get in touch via the contact form there, or you can, uh, look me up on LinkedIn, Rosemary Barnes. That’s probably the easiest, fastest way to get ahold of me personally.
Allen Hall 2025: Well, Rosemary, congratulations on the Energy Innovation Fund Awards and the new three-year effort.
If you are interested in participating with Pardalote Consulting and working with Rosemary and her team [00:31:00] in Australia, reach out to her on LinkedIn and get that process started, because this report and the data from all this analysis that’ll happen over the next couple of years will be important to the wind industry.
So you need to spend some time and get ahold of Rosemary and get this process started now. So Rosemary, congratulations. Uh, thanks for being back on the podcast, and looking forward to, uh, the next couple of years. It sh- should be exciting.
Rosemary Barnes: Thanks so much, Allen.
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