Joel and Allen meet with Blade Aerodynamics Expert Nicholas Gaudern to discuss the aerodynamic upgrades available from PowerCurve. There are multiple simple improvements that can dramatically improve the AEP. Don’t miss this episode!
PowerCurve – https://powercurve.dk
Pardalote Consulting at https://www.pardaloteconsulting.com
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Intelstor – https://www.intelstor.com
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PowerCurve
Allen Hall: Well, we’re here in New Orleans at American Clean Power 2023 with Nicholas Gaudern, CTO of Power Curve. And one of the discussions this week, Nicholas, has been about repowering. Obviously the IRA bill has a lot of money bout repowering discussions revolve around what’s involved in repowering, like what can be considered as part of the, the tax credit. Mm-hmm. And one of those items is aerodynamics, fixing the blade structurally, which is what Wind Power Lab does, and giving, you know, understand repair plans there, which everybody’s doing right now. Right. But while you’re on the blade, you might as well get some AEP back and, and get some aerodynamic performance back.
What, what are, what are the people saying here this week?
Nicholas Gaudern: You know, I think that’s a really good point, Allen. We’ve had some great conversations in the last couple of days about what is applicable. Yeah. For the tax credits. Right. You know, and basically everything by all these aerodynamic upgrades that you can put on, it’s all worthwhile doing.
If you’re on the blade doing other
Joel Saxum: work, it’s just a dollar value. Right. At the end of the day. Absolutely. You gotta spend so much
Nicholas Gaudern: to qualify. Yes, absolutely. And if you, if you get AEP back in, in beautiful. In the same time. Perfect. Yeah. So something that we’ve been talking about a lot is vortex generators.
We’ve had a lot of interest in VGs as part of that work because. It is a bit of a no-brainer really. It’s easy to do. It’s easy to do. Yeah. It’s cheap to install, and you can not only recover AP that you’d be losing through, say, contamination and erosion. Right. You can also just improve the baseline aerodynamic performance of the blade, and it’s one of those things that is, it’s a very low risk, it’s a low risk investment.
Sure. Mm-hmm. Tried, tested, proven, and I don’t think anyone’s gonna argue that a, that a VG works or doesn’t work. Right. Right. But we’ve also talked about things that you could maybe consider a little bit more exotic. Things like tip extensions, Okay. For example.
Allen Hall: So just basically making your blade a little bit longer.
Yeah, exactly. Especially where the most of the powers generator anywhere anyway. It’s on the outer third, so Yes. Making another meter, two, three on
Nicholas Gaudern: the tip. Yep, exactly. So I think with a tip extension, it’s all about getting more swept area. Mm-hmm. The bigger swept area, the more power. It’s, it’s kind of obvious.
So it’s an easy thing, I think, for customers to understand. There’s not any particularly complicated physics around. It’s just no bigger array, bigger rotor,
Joel Saxum: more power. Yeah. Those are, those are formulas that we all know and love. Yes. Right. That’s not a hard one.
Nicholas Gaudern: We can take, you know, take, take a, an older turbine, let’s say, you know, a 60, 70 meter turbine that might be knocking around and, and eligible for some, for some credits.
If you just put a meter of blade length on. You could be looking at 3% aep. Whoa. That is huge. Because you know, you’re going from a, you know, a 61, 60, 70, whatever, you’re putting another couple of meters diameter on. That’s a lot of swept area
Joel Saxum: increase. Yeah. And think about if you’re gonna drop the rotor to swap out main bearings or a generator or something of that sort, they’re doing already, that thing’s on the ground.
If you’ve got a good operational plan, yes, you can install those quickly on the ground. The ROI on that is, is.
Nicholas Gaudern: Going to be very quick. So a lot of AEP for not much money. Yeah, exactly. I mean, it’s, it’s a bigger job than a, than a BG install. Of course. Sure. Absolutely. So if you’re doing a tip extension, you’ve gotta think a lot more about the structure.
Mm-hmm. Mm-hmm. You’ve gotta think about how you’re bonding that on, right. How it integrates with the lightning system. Yeah. Absolute. Do you need, do you need to supplement the lightning system or do anything around that with the extra blade length? Mm-hmm. I mean, none of these problems are insurmountable.
No. Right. But it’s not, it’s not an on the shelf product. So the things like a VG. It’s on the shelf, it’s designed, the components exist and you put them on and they work. Right? Things like a tip extension, it’s more of a bespoke engineering project. Mm-hmm. There’s just a little bit more to it, so again, quite well suited to a bigger investment in your machine.
Where you have the money and the time available Yeah.
Joel Saxum: To, to do it properly. But you’re hitting a sweet spot in the market there too. Right? Because talking to people, you can talk to your faces blue to about a tip extension to someone that’s under warranty and they’re just gonna, you wouldn’t over. Right?
So that you’re talking, we’re talking here. PTC driven repower projects. It’s the perfect time that assets 10. 10 years and one day old at least. Yeah, yeah. Right, right. So So it’s been, it’s been around the block, it’s out of warranty. Yes. It may be under an FSA or something as well too, but that at that stage the asset owner has a little bit more power to make decisions for themselves rather than the OEM driving basically what happens
Nicholas Gaudern: to the turbine.
And that’s what you need. You need an owner who understands the turbine, is familiar with it, it’s not a warranty. Yeah. And is just prepared to, to just take that little bit of extra investment and risk to. To maximize performance. Absolutely.
Joel Saxum: So talking, talking repower here now, like Allen, you were saying around the show, I mean we talked to a lot of the big ISPs, we talked to a lot of asset owners and it’s PTC driven, repower, PTC driven repower.
We talked to one ISP that they’re more of a service oriented one and they don’t really do blades that much. And from a project that actually the three of us. Worked on together was a PTC driven repower. Yep. Where we went in and inspected the blades internally. Externally, did a big repair campaign to get them to, you know, up to a, like new status client wanted some AEP increases.
So we put on gurney flaps, we put on vortex generators. Yes. And then we also did on our side, we, we recommended an AEP campaign. Right. And then we also added the strike tape product to protect them from lightning in the future. Right. Right. So we increased, we, we reduced lightning risk, we increased the aep.
Mm-hmm. And we kept those blades by, we have a GE v wind power, went out there and did the, did the big campaign on, we kept those blades outta landfills. Yes. Right. So that big picture of the blades and landfills and all that problem, like, Hey, we just
Nicholas Gaudern: kept them running. This is exactly what we should be talking about.
Yeah. Not, not throwing stuff away because it’s 10 year old Exactly. Going out. There’s so much life and energy potential in these machines. Go and use it. Yeah. Yeah. Go and exploit that. Yeah. A lot of
Joel Saxum: those, a lot of the blades that are being repowered right now are, again, 10 years and one day old. So they’re 10, 12, 11 years old.
They’re designed for a 25 year life. Yes. Now, a 25 year life out of a blade is, is, is tough to get to depending on your environmental conditions, but if you’re. Doing a refurbish at 10 years, 25
Nicholas Gaudern: when, and you start adding on the extra AP potential from some of these devices we’ve been talking about, that’s making the business case for that much better longevity.
So much better. Yeah, absolutely. So we’re really excited about the potential and we’ve had a lot of people talk to us about it. So I think we talked about VGs gurney, flaps, serrations, maybe. Mm-hmm. You know, if you’ve got any kind of noise, curtailment issues, I don’t think it’s as big in the uk us, sorry, as it is in Europe.
Yeah.
And
Joel Saxum: farms are more remote here. Exactly.
Nicholas Gaudern: Part. Yeah, exactly. We have had some customers talking to us the show about northeast us in my neighborhood. I’ll say definitely serrations. Yes. Starting to see a bit more demand and interest in noise. Red reduction technologies. Yeah. So the thing is if you have to curtail your turbine, Or at certain times of day to deal with noise regulations, you’re throwing away so much aep.
Yes. Oh yeah. Absolutely. So that’s where you should be looking at actually attacking the source of the problem, not just trying to get around it. Yeah. Go to the source, which is the aerodynamic noise. Yeah. And then serrations of EGS can be used together. To just reduce the noise
Joel Saxum: at the source. So, I mean, at this table right here, we’re having a conversation that should be happening across the broader wind industry, you would think Right.
Refurbish and upgrade rather than take down and throw away. Yeah. Not only from you know, an ESG goal standpoint. We’re adding power and your, your, your saving cost. Yes. Right. I mean, I know that the, I’ve seen budgets where it’s, you know, on a GE one, five, say 150,000 a blade for new blades. Yeah. And we can repair them to like new, upgrade them and everything for half that cost.
Yes. Right. Oh yeah. And that’s, and that’s including the, all, all the people in the field and the, the new parts from, from power curve, new parts from weather guard, all the engineering that goes behind the, the whole solution, half the cost. Yes. And you’re increasing aap. It seems like a no-brainer to me.
Nicholas Gaudern: No, we really, really want to support that because Yeah, it’s just something that absolutely should be happening.
Yep. And the technology’s there. You know, it doesn’t matter whether the blade is 10 year old or two year old. Yeah. The aero aerodynamic technology still still
Joel Saxum: applies. Yeah. To be honest with you, a transparent conversation that we’ve been having a lot here at the show is the, the, the only stopper here is the workforce to get it done.
Really. Technicians, if you got 150 turbines that wanna do a repower, To go and fix 450 blades and install all this stuff. It’s just tough. It’s, it’s tough to find the bandwidth in, in the repair season here in the United States to
Nicholas Gaudern: get that done. And what are the time limits on the, the ptc? I mean, is that, you know, how, how long is that for, for customers to act on
Joel Saxum: this?
Yeah. What’s, when does it moonlight? You know, the, the last project that we did, like this was before IRA was passed, so we had to have everything done by December 31st last year. Yeah. And it was, and it was, you know, it’s tight. So now that the, the PTCs been extended here for a while, I think. Two, two years.
This, this is gonna be an ongoing
Nicholas Gaudern: thing. It’s amazing. I also, from what I understand, I don’t know the details, but I understand that it’s good if you have some local content. You know, if you’re, it’s a part of the new IRA bill. It is If, if you’re gonna be US made. And that’s something that, again, we’ve been looking at table.
So at the moment, power curve, we’re a Danish company. Our production in Denmark. Yeah. But there’s absolutely no reason that we can’t look at production in the USA for add on components. Yeah. Injection molded components. I’m sure there’s great injection mold companies in, in, in the us Yeah, sure. So we can, we can actually look at producing locally mm-hmm.
If that’s helping our customers to meet PTC requirements, meet goals, bonuses,
Joel Saxum: whatever. So, all right. That’s, that’s definitely a good point to touch on. So
Nicholas Gaudern: we’re, we’re investigating that heavily at the moment to see what we can do to really maximize the opportunities with this,
Joel Saxum: with this ptc. Yeah. You know, and I, and I, I’d like to speak from a personal note too, on the supply chain.
So I’ve dealt with, Power curve in the past and supply chain with you guys, no issues. Yeah, right. We know that right now it’s tough sometimes to get resins and plexus and Yes, man. And it’s nothing against the manufacturers, it’s just this, this stuff has happened with co coming out of Covid and adjusting to a lot of things.
Supply chains are, are, you gotta be stringent, right? You need a su if you’re, if you’re a decent sized company, you gotta have a supply chain manager to make sure you’re getting all your stuff. Yes. And dealing with you guys, even though it came from Denmark, no issues. It came, it came. Well,
Nicholas Gaudern: good to hear it.
Yeah, good to hear it. So kudos. Yeah. But if and any from the us, we can be even faster. Yeah, exactly.
Joel Saxum: So it can only get better. Yeah. So
Allen Hall: what’s the, if, if I in the United States, so just pick the, the, the biggest player in the United States, which is ge, right. So there’s a lot of GE one point fives,
Joel Saxum: ge sort of one point Xs.
Yeah. One six s, 180 fives, one seven. Yeah.
Allen Hall: To, to do an upgrade. Aerodynamically, what information do you need to know? Do you just need to know the, the blade length and that tells you everything? Or do we, you need to go out and do a blade scan? What, what’s the process to to increase AEP in a repower situation?
Nicholas Gaudern: Yeah, so it’s a good question. So we, we’ve established a pretty rock solid process now. Okay. And it does start off with knowing the exact blade geometry. Okay. So we would want to know the blade type, but even if it’s a GE 1.5. Eight to 2.5 meter rotor. There might be two, possibly three different blade types used on that platform.
Right. TPI or Texas or, yeah. And they have different shapes lm, I guess. Yeah. And then that means if the blade shape is different, the optimal aerodynamic upgraded configuration will also be different. Right. So, okay. So we’ll go out into the field. If we haven’t done it already, we’ll get a laser scan of one of these blades to build a CAD model.
Okay. I think on a previous spot when we talked about the laser scanning process quite a lot so once we’ve got that CAD model, That becomes the foundation for building the best upgrade pack. So get the CAD model of the blade. Do a lot of aerodynamic analysis like computational fluid dynamics. Sure cfd.
Sure. And then just look at every nook and cranny of that blade’s performance. To basically do like a blade Dynamic health check. Mm-hmm. Understand everything, get the signature of it, and then look at where you can maximize every last bit of performance along the blade.
Allen Hall: And how much information do you need about the wins at a particular site to help you do that analysis?
Do you need a lot of data there? Because with the Met Towers and they’ve been out in the site for 10 years, they should have a lot of data about, yeah, I
Nicholas Gaudern: mean, there’s a minimum. We, we just want to like the site average wind speed. To be honest, no, that’s, I mean, more, more information’s always nice, but fundamentally, site average wind speed is, is enough, but it’s more to determine the business case.
Yeah. More than anything. All right. In terms of the design, the components, it doesn’t, doesn’t really do a lot.
Joel Saxum: You, you could say, Hey, give me, gimme a year’s worth of low res CADA data and, and we’ll figure it out. Yeah. This is what your
Allen Hall: power increase look like
Nicholas Gaudern: across the, the 12 months. And the reason it’s interesting from looking at the AP percentage potential is that the more time you spend below rated power mm-hmm.
The more benefits. Percentage wise, you’ll get from an upgrade with things like vortex generators. You know, they don’t change rated power. No. They just boost power below rated. Right. More efficient. Exactly. So as soon as you hit rated, they’re not, they’re not doing anything. The turbine’s pitching, it’s being controlled.
Yeah. Right. To hit rated power. Right.
Joel Saxum: If, if you, I don’t know if you can really reveal this, but your library of, of blades that you guys have now, how
Nicholas Gaudern: many are in it? We’re around them 30, around 30 different blade models. That’s gonna cover a lot of the market. We, we are covering a lot of the, the existing market in the us Yes.
Oh, that’s fantastic.
Joel Saxum: Yeah, for sure. And so we talked about repower and blade tip extensions being ideal for a customer that knows their turbines and their, and they’re 10 years old out of warranty. What about just vortex generators? What if someone just wants to add some aep and that turbine’s only. Yeah, it might be just outta warranty or something of that sort.
Yeah. Does do you guys get a lot
Nicholas Gaudern: of customers that are doing that? Yes. And, and we’ll always start with vortex generators. Yeah. That is the first thing we’ll look at as an add-on because it’s simple, it’s proven, it’s cost effective. Yeah. So those components are absolutely where you go to first. Right.
Things like a tip extension, as I was saying, it’s, it’s a, it’s a bespoke engineering project. Yeah. You can do it and it may be worth worthwhile on the pt, but it’s a bit more extreme. You’ve gotta take the loads into account a lot more, right? Mm-hmm. If you’re putting length on the blade, mass on the blade, you’re going to want to do a more detailed load study, structural study.
So again, all this is surmountable. Sure, yeah. But, but don’t, don’t go there first. Yeah. Start with the low hanging fruit. Use the proven technology, then start looking if you have the budget and the risk appetite. Yeah. Then start looking at these bigger engineering projects for things like tip extension.
So if
Joel Saxum: you’re an asset owner and it’s, that’s not just a US thing. If you’re an asset owner globally, And you’ve got a little bit of CapEx space or a little bit of o and m. Yeah. Give the power curve guys a call. Cause they can calculate the ROI for you based on percentage that you should gain and be able to tell you when you’re gonna pay these things off.
Right. And then for the rest of the lifetime of that, that turbine, you’re making more money.
Nicholas Gaudern: Yeah, absolutely.
Yeah.
Allen Hall: Does, I got a quick question here. How does l e P play into the VG equation? It’s a lot of, a lot of upgrades in discussion on the floor this week is we’re, we’re putting shells on, we’re putting on coatings on, there’s a lot of variables there.
If you know that ahead of time. Does the VG layout change or do you know, you have a little bit of a step on like the shell? Yeah. Have a step. And that’s an aerodynamic deficiency. Do you have to take that into account
Nicholas Gaudern: at time? Yeah, we, we would, if we have that information, we would, we would take it into account in the design process and.
I think you mentioned a few different stars there. You know, shells, tapes, paints. Yep. The interesting thing is that they all have an aerodynamic impact themself. Yes. You know, just the fact you are modifying the shape of the leading edge, right. You’re maybe putting some roughness there or some steps there.
That in general is detrimental to aerodynamic performance. Okay. Now, I don’t wanna start scaring people. We’re not talking big numbers, maybe 10 some percent ap, but you know that that’s still important and the difference between a shell. And a tape or a paint is, is gonna be different thickness
Joel Saxum: quite a bit.
And will that affect a layout of VGs or a plan for gurney flaps or something like that? It
Nicholas Gaudern: would, it would impact layout for outboard vor. Right. The ones near the tip. Yep. Everything else it wouldn’t, it wouldn’t affect, yeah. But let’s say, you know, you. You had an l e P system that that did change the leading edge shape considerably.
Mm-hmm. It may be that VGs can play a big role in mitigating some of that negative impact. Yeah. Yes. From the l e P being. Yeah. Right. Yeah. And you know, as I say it, it’s, there’s not a one size fits all anter. You have to look at the aerodynamics of each and every solution and decide what’s best. And one thing I would say is don’t just blindly put on l e p.
You know, if you’ve got a blade that fundamentally is okay, there’s a little bit erosion, but not much. It may be putting on l eep loses you more AP than your, than you’re gonna gain back. Right. But that’s maybe more of an extreme scenario, but it’s still something that should be calculated. Mm-hmm. And looked at, you know, don’t just slap on a third of the blade covered with l e p.
Yeah. Mm-hmm. Work it out, you know, look at the, look at the potential losses, the gains, mitigating factors, and, and make the decision around the aerodynamics, not just a structural decision. Yes. It
Joel Saxum: kind of brings me in mind of a conversation I had last week. I was at a Energy Insurance America’s conference.
And it’s the same thing here for everybody. A note there is experts out there. Yes. Right. You don’t have to just cowboy the things up and we think we should throw this and we think we should throw this up. Call the experts. Yeah. We always say like, if it’s an aerodynamic thing, call power curve. If you want to talk lightning, call weather guard.
If you know, like blade fatigue damages, like call wind power. There’s, there’s, there’s experts out there, whether you’re an asset owner or you are an I S P or you’re a service company or you’re fixing blades or anything. Call the people that know what they’re doing Yes. And get it done correctly.
Nicholas Gaudern: Yeah.
Yeah. I think talking about l eep, because we have aerodynamic models of blades, we can model the L eep. Yeah. Mm-hmm. We can model the impact of it. So again, you don’t, you don’t need to guess. Take take the guesswork out of it. Yep, yep. Work it out. Make the right decision based on, based on the
Joel Saxum: data, the, the, there’s data knowledge there.
Use it. Yes.
Allen Hall: Yeah. And, and don’t put VGs in front of your lightning protection system. Can we just say that? Yeah. Because Lightning and aerodynamics are tied together, and I, I see these upgrades happen that are just a little helter skelter. Yep. And even some of the OEMs, I’ve seen some OEMs do this, where they start putting aerodynamic fixes where the l, where the lightning protection system is, and it degrades the performance of the Lady Protection System.
And they wonder why they’re having lightning damage while those AEP fixes.
Nicholas Gaudern: Keep, keep a, keep a clean zone locally. Yes. Around the lightning system. Give it some room to work. Yeah. Yeah. We’re not, we’re not talking, you know, a huge, just, you know, leave, leave a meter. Yes. Leave a, leave a clean zone. Don’t, don’t start, you know, drilling holes in blaze, putting drain holes in, putting lumpy, bumpy things.
L e p run. Yeah. Putting l
Allen Hall: e p in front of the Lady Protection System. Yeah. Why are we doing that? I’m still. Dumbfounded
Nicholas Gaudern: by that, but Well, it, it’s, it’s a system integration thing, isn’t it? It is. It’s a system. It is.
Allen Hall: Aerodynamics is working and they’re trying to improve the blades. Absolutely. Lightning protections.
People are not really thinking about what the impact is there and then the operators get
Nicholas Gaudern: handed a big bill. I think with a lot of engineering problems, there’s just, you know, you need to take a holistic approach to this. Yes. Take a system level approach. Aerodynamics structures, lightning control loads, they’re all linked.
Yeah. They’re not independent. So consider So consider them together. Yeah. And, and that’s well, and that’s what
Allen Hall: power curve’s good at. Yes. You can look at all those things together in a really accurate finally resolved model that makes it almost obvious. Yes. Even to the novice, like me, I’ve seen a lot of your products and.
I don’t know a lot about aerodynamics, but I can tell where clean air is. And clean air isn’t from your models.
Joel Saxum: It’s, you know, that’s why he, it’s really good. That’s, you know, why’s, why he put his kid into school for CFD? Right. See, he’s trying to build that knowledge at the dinner table at night. Yeah. Well
Nicholas Gaudern: that’s what he should be doing.
Yeah. That’s what he should be doing. So, and you know, the more, the more aerodynamic knowledge in the world, the better. The better. Yeah. In my opinion.
Allen Hall: So Nicholas, thanks for being back on the podcast. It’s great to have you in America again in New Orleans. We’ll see you in America at Next year in Minneapolis.
Yep.
Nicholas Gaudern: Course, I think before that we’ll be at o and M in San Diego. Oh, nice. Back in San Diego next year from what I read. Yeah. Yes. That’ll be awesome. Fantastic to you.
