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T-Omega’s Solution to Simplify Offshore Wind Turbine Design
Rosemary interviews Jim Papadopoulos, the CEO and co-founder of T-Omega Wind, about their unique floating offshore wind turbine design. Resembling a ferris wheel, the lightweight T-Omega turbine aims to overcome challenges like high costs and difficult maintenance faced by traditional offshore wind farms. Learn about the innovative features of this design and the progress made so far, including the installation of a prototype off the coast of Massachusetts. Visit https://t-omegawind.com/
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Rosemary Barnes: Welcome to a special episode of the Uptime Wind Energy Podcast. I’m your host, Rosie Barnes, and I have with me today Jim Papadopoulos, who is the co founder, chief engineer, and CEO at T Omega Wind. Thanks for joining us, Jim. Pleasure to be here. So T Omega Wind is a unique floating offshore wind turbine.
It’s designed to take advantage of being on the water rather than trying to force an onshore design to work on the water. It’s designed to be lightweight in the expectation that will enable improvements in cost and manufacturability. We’ve actually spoken about Tiermaker on the Uptime Wind Energy podcast before, it was episode 132.
It most resembles a ferris wheel, I would say, if I was trying to find some, yeah, analogy. So it’s got a four legged pyramid frame that supports a rotor in between the two halves. So it’s got, frame on the upwind side and the downwind side of the rotor. Since we spoke about them on the podcast, Hairmaker’s made some progress.
They’ve installed a 1 16th scale prototype off the coast of Massachusetts. And I’m going to ask him how that went a little later on in the podcast. But first, Jim, let’s start at the start and find out your origin story. What motivated you to create a new floating offshore design?
Jim Papadopolous: Well, I have to say, I didn’t set out to say there’s got to be a new one.
And here it is I was entranced by offshore wind. And shocked by the costs. This is first bottom fixed and then floating only slowly. I came to realize that floating is, was really not a product yet, that there are just trials and ideas. But looking at offshore wind, we could see a bunch of things very heavy floating foundations, great difficulty of repair, infrastructure and supply chain needs especially as the capacities kept getting bigger and bigger in a way, because the cost of electricity was high.
So if you make it even bigger than the cost per turbine of the maintenance And the installation doesn’t go up too much. So you actually get more energy for, a lot more energy for a little bit more costs. So there’s discussion of 15 megawatts and 20 megawatts and 25 megawatts. All of which means new generations of turbine technology and it need deeper ports and more metal.
So we looked at all the, all these things and thought, hang on, there’s got to be something better and noodled around until we convinced ourselves that’s something which was shallow draft. And therefore following the water elevation. So wave following and therefore having a lot of motion, which is not tolerant, tolerated by the current turbines.
But if you redesign the turbine, you can get by with this very light, shallow draft platform. And as you’re in the water, you can think about wind yawing to remove a bunch of mechanism. So it’s like that we both, we were appalled by the big costs. We saw something easy to do, and then as we fleshed it out lots of pieces fell into place as a nice system.
Rosemary Barnes: Yeah, right. I’m not sure that I would look at any aspect of designing a totally new I don’t know, in some ways revolutionary design of a floating offshore wind turbine. Easy wouldn’t be a word that I would. associate with that, but you must have a very good team working on it if if that’s an easy challenge.
Jim Papadopolous: Well, we’re naive. We don’t know what we don’t know. So, that’s part of it.
Rosemary Barnes: I think that’s the best way to go into it. Otherwise that, people who aren’t naive tend to. Stick with the status quo because they know it works and they know how many problems you get when you deviate slightly from that.
So, okay. So, I mean, you mentioned some challenges with existing, I mean, not just floating offshore wind, but all offshore wind has most of those challenges, right? I mean, it’s something we talk about a lot on the podcast is in the U S at least the big problems with port infrastructure and the right kind of ship.
And, all those sort of, I don’t know, you might say boring details. If you’re someone like me, that’s interested in turbine technology, you wouldn’t think that you had to worry so much about those kinds of logistics and I guess supply chain is another one. So yeah, are there any more disadvantages that you were hoping to overcome?
Jim Papadopolous: The current design usually needs big cranes. That’s the way people can imagine assembling them. And we would like to say, well, is there a way to do it without a crane? And the current designs are not suited to deep water. And I believe it’s just the cost of the catenary chains at greater depth.
You have three or four whacking great chains at great length, that really add a lot of cost to the mooring. We’re trying to work with synthetics and anticipate being able to go to 2, 000 meters depth. Then there’s the kind of the size of market, the current design with with I don’t know how to put it, with big turbines and with tough maintenance challenges end up with large wind farms.
And so there are going to be markets where you really would only need 50 megawatts, not 500 megawatts. So we can imagine having a few turbines or having just one and quite a bit smaller turbine. So, if you think about scaling down, there are a lot of, there are going to be a lot of places that have water.
And have wind and don’t, can’t work with a one gigawatt wind farm. And we think we could serve those as well as the gigawatt style utility wind farm in shallow or deep water. Yeah,
right. That’s that sounds like a good strategy and I’m definitely going to be interested to hear your solutions for those problems, but I think.
First, we better go back and have you explain what is the T Omega design and what are the, relevant aspects of it that aren’t immediately obvious when, think of it like a Ferris wheel, like I described it.
To talk about one specific size, a 10 megawatt capacity where the hub height for a conventional offshore would be 120 meters.
We have that hub at 120 meters. We have the conventional blades. And then we have a base, which is about 100 meters square, formed of four conical and rather shallow floats. The floats penetrate down into the water five or six meters. So those four conical floats support four legs that all point up close to the same point.
They’re the two ends of the axle, the short axle. And then there has to be bracing between the floats so the legs don’t splay apart. And then that’s a pyramid structure with tremendous structural integrity. Because there are only triangles in the structure, so to speak, four faces that are triangles and then a triangulated base.
And this very rigid and very light structure, And UNLITE is a stand in for saving cost, less material, and it’s a stand in for easier assembly and easier towing. That whole system is going to be moored by a single line, something from a point, something like a trailer hitch on a land trailer. So there’s going to be a point, off, off in front of the turbine, another 50 meters or so, a single point.
And a mooring line will come slanting up from the ocean floor, maybe 45 degrees or 50 degrees. to that point, and the imagined projection of, continuation of that line would go right up to the hub. So that’s a line that points from the ocean floor to the hub. With this arrangement, the tremendous wind thrust on the rotor doesn’t tip the system backwards, but just presses it a little deeper in the water.
And in fact, we will have a separated, but kind of in line continuation of that line as a tensile element between that pitch point. And the hub. So if you stand back, it looks like a single line from the ocean floor up to the hub. Now, when you have an angle like that, 45 or 50 degrees, then when the wind changes direction, you swing in a large circle, depending on how long the line was, which is from how deep the ocean is, and to keep that watch circle to a limited size.
In deep water, we would actually have three anchors and three lines coming up to a point, maybe you. 50 meters below the water surface and that single point below the water surface, a small buoy, will carry the line which otherwise would Be to the ocean floor. So a single line from that buoy and then a rather small circle that it rotates around and the turbine being supported by a single line, like a ship at anchor is meant to be blown downwind.
So it always faces the wind and festooned or kind of looped onto that single line is an export cable. And because the thing may change direction from week to week, we have to think about having a rotary union, an electrical union, so that it could take several swings around, and either, either we let the line wind up three or four times and come back and unwind it, or we have to have a slip ring.
And let’s see what else is going on. We’ve got the shallow floats.
The rest, what you could, from what you could see, there would be the three blades rotating around the rather short axle. And a large direct drive generator is the thing everyone understands, though, in a fantasy of mine, in some future day, we would have a belt drive down to a smaller generator down.
near the water. And one especially important thing to point out is that there is almost no structural mass below the waterline. Whereas conventional floating turbines are like icebergs with more than 80 percent of their weight underwater.
Rosemary Barnes: Okay. And the generator is that special design for It doesn’t look, it’s not that similar to existing wind turbines.
So am I right in assuming that’s a design that you have or will have to come up with on your own?
Jim Papadopolous: Well, the generator, we’re not generator specialists and there are 10 megawatt and 15 megawatt direct drive generators. And we’d essentially be using one of those. Maybe with a slightly different, bigger bore because we have a large diameter axle, but a standard generator, basically.
Rosemary Barnes: It’s got a single connection point. So you’re imagining that this is going to be quite simple to swap them out. Can you explain how you would expect your maintenance to look? And you also, you mentioned that. On your website, at least you mentioned that it won’t need large cranes. Can you also explain how that is?
Like, what is the difference to regular floating offshore wind or yeah, or any kind of, what’s the difference to regular offshore wind and why you wouldn’t need a crane?
Jim Papadopolous: Maintenance is something like a 15 or 20 percent of the cost of electricity of floating wind turbine. So it’s an expense, an expensive proposition.
And we don’t believe it’s safe or a good idea to put people on a turbine that’s bobbing in the waves while the ship is bobbing in the waves. And we hate the idea of having a big crane and needing calm weather to hoist some big piece. So, our notion for maintenance is that since there’s a single point of contact, we like the idea that you can bring a fresh turbine out, we would plan to have one or two extra turbines, they’re not very expensive.
So, bring a fresh one out. When one needs maintenance and swap the rope across, swap the mooring line across and swap the array cable across, which we think if we develop the right technology could be a one hour swap. It’s bringing the towing points of the two turbines close together and swapping the rope and swapping the electric line, taking away the turbine wanting maintenance.
And then once. That’s a shore and we’re aiming to engineer this for easy and kind of rapid towing in almost every weather. Once that leaves, the good turbine is working, so there’s no downtime effectively. And the one we get ashore, of course, you could have a crane. This is an economic question. Do you use the time savings of a crane to justify the cost of a crane?
And that’s fine, but our design is so rigid that it’s ought to be able to be tipped on its side so that the blades are near the ground and that tipping is a, should be a two hour winching operation or something. So we have a, an elaborated scheme, both for assembly and then for disassembly and maintenance that assure it can be tipped.
Thank you. You can reach the bits you need, replace the parts you need, replace anything, take fresh parts from stores and refurbish the old parts later and tip it back up and tow it back into the water.
Yeah, even for fixed bottom offshore wind, maintenance is the huge thing. I mean, the industry itself is still young, so, we haven’t really had a lot of time to see what the.
The true reality of maintenance is going to be not just for the average, but also for the, like, worst five or 10 percent of wind turbines, that makes a difference if you’re going to have long downtimes. And if you’ve got to get personnel out to site every day in a boat or a helicopter, then you can just imagine how much that adds costs if you’ve got your turbine shut down the whole time.
So I can a hundred percent get on board with the concept that you have for maintenance of. Yeah, being able to bring it to shore so that you bring the turbine to the people and yeah, potentially even having a set of spares there so that you can keep things going with the spare turbine while you work on the new one.
I guess that’s going to depend on if if you’ve got space at port to store that and you’ve got the extra money to keep it there, but yeah, like some of the. The floating offshore wind farms now are looking at six months or so of downtime while they fix the issues that they’ve got. So, like you can afford a spare turbine if you’re, if that’s the alternative.
The
parameters that will go into estimating downtime include things like the towing speed, the swapping speed, and then maybe the disassembly time at port and we’re, and we’re really looking for order of magnitude improvements compared to what any what’s predicted for a semi sub.
Rosemary Barnes: Okay. So that all sounds great. Definitely. Very good on, on paper, but on paper is not what we need. We need, actual turbines out in the ocean generating actual electricity. So can you tell me a bit about how far you are along on that process?
Jim Papadopolous: There are a lot of things we don’t know. And for example, our, there’s a, the certification process as we understand it through DNV would involve normally.
Giving everyone a good feeling that you could manage a 25 year fatigue life or something. There’s a lot of calculations involved in that. And we’re upending that thought and saying, well, what if it’s only a three year fatigue life? Of course, I’m only saying that as an unlikely extreme case.
The main idea is that instead of aiming to last a really long time, we expect to replace components as needed year after year, like car parts. So we that’s kind of the beauty of many trips ashore and easy going ashore. And I do, I hope the structure has a lot of air galleries such that with a little bit of air pressure, you can tell if there’s a crack growing somewhere because it leaks.
And so, we’re thinking, well, let’s design for a three or four year life. And so the DNV folks say, hang on, we have to do a study to know what kind of validation we’re going to need. So, right at the beginning, we’re stuck on now knowing exactly what to do. We don’t know exactly what to do.
So we’ve, the very, the most unusual aspect of our thing is the geometry and the mooring and the shallow draft. So we’ve been looking at the hydrodynamics, which means, you get something more like that and then big waves come along and does it tip over? Does it leap out of the water? Does it swing crazily?
What happens? And so some of our study was in wave tanks. We went to Glasgow and we had one at the University of Rhode Island. Look, looking at the largest waves they could supply, which scaled would be, it would be like 30 meter waves in 120 meter, tower hub height. And we saw, kind of beautiful behavior.
And then we’ve been using this program called Open Fast, which is developed by the National Renewable Energy Lab. And it’s considered one of the better programs, and it has all kinds of hydrodynamics and wind forces and mooring forces. And so we’ve kind of tuned, they adjusted the software to work for us, the added features.
And then we’ve been exercising the software and as you must, you look and see it, look at the results and hope that nobody put a minus sign in the wrong place. And we, it all looks reasonable and therefore, yes, with the open fast work coming at it from several angles, very nice behavior in large waves.
And we’ve just started the work of with a wind thrust. Due to energy production and also in a storm case with a wind drag, not a rotor thrust so much so that kind of numerical work which we, it looks similar to the wave tank work. So, we’re, we’re always looking and trying to decide, do we trust it?
And how far can we trust it? And what does it mean for the design? And then we want to change the design. So, in this and OpenFAST work. We saw, we had a look at something with a 70 meter base, and my understanding of the hydrodynamics is it might work better if it was a 100 meter base, so we swapped the model.
And indeed, there was much less hub acceleration, and there was less bending moment in the towers, and bending moment in the braces. And there were lower slamming forces on the floats with this 100 meter base, so that was an inspired guess that seems to be okay, and now we’ve looked at the weight and so forth, and we’ve been trying to we’ve been trying to suit the design to to tolerate 50 year storms in the North Atlantic.
Such that, what’s the biggest bending moment you expect in a three hours, fifty, three hour, fifty year storm of this or that peak period, wave period, and significant wave height. There’s an environmental contour we’re using. And so, yeah, it’s way better than just guessing, but it’s not proof.
And so, this this OpenFAST work has to continue, and the structural design has to be what’s the word fleshed out to suit those loads, at least for ultimate states, and we have to then decide What does it mean for fatigue and what kind of life can we really work with? And I’m saying for some parts, maybe as little as three or six years.
Rosemary Barnes: Yeah. Okay. I mean, I’m assuming that would be an initial lifetime as you learn more about it, then you would be able to improve the components that are wearing out in three to five years. Right. Cause you could, because the the cost of the turbine is so small compared to the total cost of the wind farm.
Is that why it doesn’t matter? Well,
Jim Papadopolous: I, in my costing, I figured, I just imagined replacing every part of the structure over 10 years, and that was a good cost. So it’s just that if the maintenance is simple and cheap, then have more of it. That’s kind of, kind of my simple minded thinking.
But so all, the design has to be elaborated and studied with greater fidelity, I guess, is the point. And we have to, we found a problem with wind alignment, because a turbine, an operating turbine does not work like a ship at anchor. There’s something we didn’t know. So it’s not that the thrust force on the rotor is downwind, the thrust force is normal to the rotor.
So it doesn’t really self center when it gets off axis. And so the NREL put in a model of individual pitch control, which they have in their controller that they built for us. And that can, if the thing has swung away from alignment with the wind, which it would at certain wind speeds, it can be returned by adjusting the pitch, once per revolution, like a helicopter rotor, to get the center of pressure off one side.
So, so, so there’s the, so there’s the structural work. There’s the kind of the energy harvesting work, there’s the stability when energy harvesting, we have to look very much at the towing, at the swapping, at the at the erecting. So there are a lot of questions, but probably I would say that the open fast work and the wave tank work should give people confidence that it’s not, it doesn’t look like a disaster straight off so that we should get funding to work on something bigger and higher fidelity.
Rosemary Barnes: A couple of good things that I can see in your development approach is one, going and test testing out interesting things that you’ve seen in the simulation and yeah, making sure that they broadly make sense and to using the open fast software, which is developed for wind turbines and has been validated against, no wind turbine exactly like yours, but at least for wind energy.
So I think that puts you definitely a few steps ahead of where you would be if you had done what seems to be the typical thing of just, yeah, grabbing a Ansys license and and having a crack at a model, which you definitely do. And you can definitely get nice colorful graphs that will probably get you investor dollars, but you’re also in for a rude shock when you build something.
Jim Papadopolous: We’ve been very lucky to work with the NREL folks because they’ve. They’ve sort of attacked all kinds of problems in all kinds of directions, and they aren’t in the business of putting out a specialist thing that gives one clear, beautiful answer, and then you’re done. They’ve worked with, all the gusty winds and all the spread spectrum sea states and this, that, and the other, so We have we’ve, one thing we’ve done is we’re using known naval architecture spectral techniques to estimate the worst case, either bending moment or acceleration or float lift in a given sea state.
And we trust that these are done. This is a good approach. And so we’re using the RAOs. That NREL can give us for all kinds of forces and moments and so forth. And so we like that. We’re going to back that up with the kind of the nonlinear simulation in the same C state to see that it does more or less match.
And then we have, we’re trying, we want to compare the wave tank results to the NREL model as if placed in the wave tank. We haven’t done that yet, but we want to make sure damping looks about right so that a lot of things we want to do to make it right and to do the kind of robust. And, highly varied loading that was called for.
So that’s enough for now on that.
Rosemary Barnes: So I am really keen to hear about how the different phases of development have gone and how long you’ve spent on it. Like how, when did you first start working on this and what kind of a team did you assemble? What backgrounds do you have people from oil and gas industry?
From academia, from the wind industry, how did that start out?
Jim Papadopolous: So it was, it started off with just another professor and myself. I was a lecturer and he was a proper professor at Northeastern University in Boston. He’s been doing work on wind turbine, offshore wind turbine towers, bottom fixed, doing the research and the loadings and so forth in the environmental conditions.
And when I When we made friends and I started telling him my ideas about floating, he liked them. And so we, I think we got a couple of small grants, just working on an idea. Then we formed a company, I think around 2020 incorporated and. Invited people in, we got three very talented people. One of them was a serial entrepreneur and he had a small wind turbine company.
He’d been in offshore oil work for a while. He’d been, he’s a patent attorney. He’s a, an MBA, he’s a tugboat operator. He’s a pilot. He’s a, he’s sort of done everything. Yeah. He’s a very versatile guy. And we need, we needed good IP advice in the company. And then we hired a woman. She had been she had started her career at Equinor, the Norwegian woman.
And she ended up, she got educated in the States and got a business degree and she ended up at Duke. She was at Exxon for a while and then at Duke Energy in the U S for 20 years. And, kind of a fairly senior executive who wanted to get into something clean, as opposed to Duke’s world of coal and oil.
And then we have Dave Forbes, who was a venture capital, he was in politics for a while, helping various presidential and govern, gubernatorial campaigns. And then he was at a venture capital firm, maybe in Hong Kong or somewhere. And so he’s. He’s our outward face to try to get investment because he knows it from the inside.
And so all those people came, we formed the company in 2020 and those people came on at sort of half year intervals and now it’s just turned 2024.
Rosemary Barnes: And they brought with them funding that enabled you to build this 1 16th scale. No. How did you come by the funding to buy your, to, yeah, to build your 1 16th scale prototype?
What, how did that come to be?
Jim Papadopolous: So what happened is we’ve had a few, we’ve been in a couple of accelerators where you get 20 or 50, 000 or 100, 000. And then we got a, an STTR grant from the National Science Foundation that’s You may have heard of it as an SBIR grant. That was probably 250, 000 and let us get the NREL work done.
And then the state gave us a matching, a 50 percent matching grant, 120, 000, and that let us design, build and launch this prototype.
Rosemary Barnes: And so it was recently that you put that prototype in the water and then I saw news reports that it was removed early. Can you tell me a bit about how that experience was getting it in there and yeah, what its short life in the water was like and what’s next for the company?
Jim Papadopolous: Well, we were hoping for a two month trial. That was what the permit is for. And we wanted to have. The wind thrust and the torque of a low, of a, we didn’t have a generator, but we have a pump, so it was going to make power, and we were going to then get the sort of the hydrodynamics with the thrust force, in the given sea states, we wanted to see the orientation to the wind, we wanted to see the RPM, the rotor went, we wanted to see all kinds of things like that, but it turned out that the data acquisition wasn’t working, and also that there was no drag torque on the rotor.
This is something was installed backwards. In the installation that day. So it needed to be tweaked and that never happened. After some internal debate, it was pulled out of the water and taken to bits.
Rosemary Barnes: All right. So it’s there on, on ice until you’re able to, in storage waiting for another. For repair and waiting for it to stay back on the water.
Jim Papadopolous: The repair is trivial. It’s waiting for the group decision to put it back in.
Rosemary Barnes: I will be interested to see how that goes because it’s a really common story where, you know, a great idea, a great product, it, there’s always some frustrating mundane or, interpersonal problems that end up, you causing big issues for our product and.
It’s yeah, it’s not just sad for the individuals involved. It’s sad for everybody that wants to see great renewable energy technologies. So, yeah, I will be definitely rooting for you and following closely. Thank you so much for talking to us about Tia Omega and yeah, I’m wishing you the best of luck for the future.
Thank you, Rosemary. Thanks for listening and please give us a five star rating on your podcast platform and subscribe in the show notes below to the Uptime Tech News, our weekly newsletter. I’ll see you in the next one.
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Motordoc Diagnoses Drivetrains From the Ground
Howard Penrose of MotorDoc joins to discuss the circulating currents killing main bearings and drivetrain checks without a climb. Reach out at info@motordoc.com or on LinkedIn.
The Uptime Wind Energy Podcast is brought to you by Weather Guard Lightning Tech, creators of the StrikeTape Ultra LPS retrofit. Subscribe to Uptime’s Substack newsletter. And check out Rosemary’s “Engineering with Rosie” Youtube channel. 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: Howard, welcome back to the program.
Howard Penrose: Hey, thanks for having me.
Allen Hall: It’s about time everybody realizes what motorDoc can do. There’s so much technology, and I’ve been watching- Yeah … your Chaos and Caffeine podcast on Saturday morning, which are full of really, really good information about the motorDoc as a company, all the things you’re doing out in the field, and how you’re solving real-world problems, not imaginary ones- Yeah
real-world problems. Oh, yeah. Yeah, and
Howard Penrose: whatever annoys me that week. Exactly. And, and whatever great coffee I’m trying out. Yes. Except for a few. We’ve had the ReliaSquatch down our- Yes … um, a couple of times. Uh, yeah, no, I, I enjoy it, and we gotta get you on there sometime. I don’t do- I, it- … a lot of interviews other than an AI character we put in.
Allen Hall: It’s a very interesting show because you’re [00:01:00] getting a little bit of comedy and humor and s- Yeah … and a, and a coffee review, which is very helpful because I’ve tried some of the coffees that you have reviewed, that you’ve given the thumbs up to. But if you’re operating wind turbines and you’re trying to understand what’s happening on the drivetrain side, on the generator, everything out to the blades even, main bearings, gearboxes- Yeah
all those rotating heavy, expensive parts, there’s a lot of ways to diagnose them-
Howard Penrose: Yes …
Allen Hall: that are sort of like we can look at a gear, we can look at a joint, we can look at roller bearings, whatever, but motorDoc has a way to quickly diagnose all of that chain in about- Yeah … 15 seconds.
Howard Penrose: Well, a little longer than 15 sec- more like a minute.
A minute, okay. It feels like paint drying. But- Uh, in any case, yeah. Uh, uh, and, and what’s kind of funny is, um, back in the ’90s, uh, EPRI actually accidentally steered the technology away from its [00:02:00] core purpose, which was in 1985, um, NAVSEA, the US Navy, had done research on using current signature analysis for looking at pumps, fans, and compressors, the bearings, the belts, the components, all the rotating components using the motor as the sensor.
Not too much different than we are now. I mean, mind you, we got better resolution now, we’ve got, uh, more powerful– I mean, I look at my data from the ’90s, and now it’s completely different. Um, and then Oak Ridge National Lab, same thing, bearings and gears in motor-operated valves. So in 2003, we were the first ones to apply electrical and current signature analysis to some wind turbines in the Mojave Desert.
Wow. Yeah. So, um, nobody had tried it before. Everybody said it couldn’t be done. And, uh, that was a bad thing to say to me because- … it meant I was gonna get it [00:03:00] done. Right. At that time, um, we were looking at bearing issues and some blatant conditions with the, um, with the, uh, generator using a technology called Altest, ’cause I was with Altest at the time.
And, uh, I had taken an EMPath software and blended it with a, a power analyzer, and they still have that tool to this day. I was using that technology all the way through 2015. 2016, I should say. And then- And then switched over to the pure EMPath, which was more of an engineering tool. And then more recently, in 2022, uh, made the decision to ha- to take all the work we’d done on over 6,000 turbines, uh, looking at how we were looking at the data and what we were doing on the industrial side, and took a, uh, created a current signature analyzer that would do one phase of current to analyze the entire powertrain.
Allen Hall: So when you tell [00:04:00] operators you can do this magic, I think a lotta times they gotta go, “
Howard Penrose: What?” Oh, yeah, yeah. They don’t understand it because they’re used to vibration- Right … which is a point analysis system. Right.
Allen Hall: Vibration at this- Yeah … particular location. Yeah. One spot- Even if it’s- … or a couple
Howard Penrose: spots
triax, they’re reading through material, up through a transducer. Hopefully, they put it above the bearing and not in the middle of the machine like everybody is now, because everybody’s trying to sell a sensor. Right. True. They’re not selling a- they’re not selling accuracy. They’re just selling sensors.
Right. So, um- Yeah … you know, uh, I, I’ll, I’ll even talk about one of the companies here. We’ve got Onyx here, and they do it right. I mean, they’ve been doing it right pretty well because we’ve been doing some of the same towers they’re on, and we can match the data they’re getting. Oh, good. Right? Yeah. Uh, so but they get it in multiple spots, and there’s areas they can’t quite reach, so we’ll detect those areas as well.
So it’s a good melding of two technologies.
Allen Hall: Oh, sure. Sure,
Howard Penrose: sure. You know what I mean? Yeah, yeah, yeah. So when you have electrical signature and you have vibration, but in [00:05:00] cases if you don’t have vibration, we’re a direct replacement.
Allen Hall: Because the generator- I
Howard Penrose: dare say that.
Allen Hall: Yeah. Whichever–
Howard Penrose: I dare say that, um, with- Well, the
Allen Hall: generator is acting as the sensor.
Howard Penrose: The air gap. The air gap in the generator s- specifically, yes. Yeah. Generator, motor, transformer. Right.
Allen Hall: Yeah. So any of those- Mm-hmm … you can clamp onto, look at the current that’s on there. Everything that’s happening on the drivetrain, in the gearbox, out on the rotor- Yep … main bearings, all of that creates vibration.
Creates a torque. T- a, a torque. Yeah. Yes, more exactly a torque. Yeah. And that’s seen in the generator, in the current coming out of the generator. Yes. So those signals, although minute, are still there. Yes. So if you clamp onto that current coming out of the generator, you’ll see the typical AC sine wave sitting there.
But on top of that- Is all the information about how that drivetrain is doing
Howard Penrose: Absolutely, and everything else. Anything electrical comes through [00:06:00] that. So what you do is just like vibration, you do a spectral analysis. So every component has a frequency associated with it, just like vibration. It’s, as a matter of fact, I, I keep having to try to explain to people electrical and current signature analysis is no different than vibration analysis.
It’s the same concept. We use the same tools. The signature looks just a little different. It’s a little noisier, um, but you need that noise in order to see everything. But we have a time waveform, and instead of, um, inches per second or millimeters per second, whatever, you know, uh, velocity, acceleration, and displacement, uh, what we end up with is decibels is the optimal method.
You can look at straight voltage signatures at those points or, or current signatures, but the values are so small that you have to look at it from a logarithmic standpoint. Right. There are some benefits to it versus vibration, and there’s some things that aren’t as good as vibration. [00:07:00] So, you know, we, we do…
You have to… Any technology is gonna have their strengths and weaknesses. Sure. So we will see everything all at once. Load doesn’t matter. Right. Speed doesn’t matter. It’s… Only reason speed matters is the location of the frequencies. Uh, so the higher the resolution, meaning the longer you take data, the less chance you have on a lightly lo- loaded machine of blending the peaks together.
Right. Um, on the flip side, if I have two bearings turning at the exact same speed, I couldn’t tell you which one it is. Because they’re the same. Right.
Allen Hall: And the mechanical features of that bearing is w- what creates the signal that you’re measuring. Exactly. So if a bearing has five rollers versus 10, just imaginary thing.
Yeah, yeah. Five rollers versus 10 has a different electrical signature, so you can determine, like, that bearing, that 10 roller bearing- Yes … has the problem, the five is fine. Yes. Yeah. That’s the magic, and I think people don’t translate the mechanical world into the electrical world. That that’s what’s [00:08:00]happening.
They,
Howard Penrose: they don’t because, because what’s happening is they named it wrong.
Allen Hall: Yes.
Howard Penrose: A majority of our users are mechanical folks. Sure. Our vibration analysts and stuff like, ’cause they know how to look at the signatures. Right. Everybody tries to force it on their electrical people, and electrical people go, “We don’t know what this is.”
Yeah. And it’s, it’s, it’s a matter of that training and, and, you know, in the electrical world, you’re not taught to look at that. Right. Yeah. It doesn’t matter. Mechanical world, you’re taught to look at that. So our intern, we were trying to bring in electrical engineering interns and found out that just wasn’t working.
So last year, I brought in my first, uh, intern that’s, you know, he’s been with us now since I brought him in. Okay. Uh, and, uh, Amar, and, uh, you know, he’s helped us develop our vi- uh, vibration software to go along with it. Guess what? It’s the same thing. It’s the exact same sy- system Um, but we just take in a vibration signal instead.
But he picked up on it immediately as a [00:09:00] third-year college student. I can take somebody with a decade as an electrical engineer with a PhD and they can’t figure it out.
Allen Hall: Well, because you’re, you’re taking real- Because it’s different. Yeah. It’s r- well, it’s real-world components-
Howard Penrose: Yeah …
Allen Hall: creating electrical signals.
That’s hard- Well, you have- … to process for a lot of people. Yeah,
Howard Penrose: yeah. It’s
Allen Hall: just not
Howard Penrose: something that we do every day. But that’s… If they, i- if we sa- i- i- if you’re looking at vibration and you start looking at the sensor, it gets complicated too, ’cause guess what? It’s an electrical signal. Right. It’s, it is technically electrical signature now.
It’s converting a
Allen Hall: mechanical signal- Right … into an electrical signal, which is what’s happening in the generator anyway. Yeah.
Howard Penrose: Whether it’s a piezoelectric cell that’s generating a small signal- Yeah … on top of a small waveform that you then take out, you demodulate, uh, or it’s, uh… So you take that carrier frequency out, or it’s a MEMS sensor, which is the same thing.
You know, the, it just sees some slower s- It, it does more of a digital output. So you, you, you know, you have those, or you [00:10:00] have this, which just basically uses a component of the machine to, to, as its own sensor. There is one other difference between them, too, and, uh, I find this very useful when I’m going out troubleshooting something that other people can’t figure out, uh, ’cause we use all the technologies.
So in this case, it would be, uh, the structural movement. Okay? So, so say I have a generator and there’s something wrong with the structure, and the whole machine is vibrating. So y- well, if I put a transducer on it, they might think that’s vibration or something else. We don’t see it. Right. We only see directly exactly what’s happening with the machine.
Sure. So a lot of times when we go in to troubleshoot something that people have done vibration on and everything else, it’s been pro- a, a problem for them for years. We walk in, and all of a sudden we’re identifying whether it’s the machine or it’s something else right off the bat. Then we can take a look at the vibration data and [00:11:00] say, “Okay, it wasn’t the bearing or the bearing, um, structure.
It was, you know, the mounting.” Right. It wasn’t
Allen Hall: fastened
Howard Penrose: down properly. Yeah,
Allen Hall: yeah. Right.
Howard Penrose: Go tighten that bolt. Right, exactly.
Allen Hall: Well, I mean, that’s the cheap answer. Yeah. I’d rather tighten a bolt than rip apart a motor or a generator- And, and- … every day …
Howard Penrose: and that’s the whole point. Now, there are other strengths that go with it.
So for instance, on the powertrain of a wind turbine, I can tell you if you’ve lubricated the bearings correctly. Wow. Because part of what we do is we do take those electrical signatures, and we convert those over to watts. Watts is an energy conversion. Sure. So you see that as heat or some type of loss.
So whatever, whatever’s being lost there is not being sent to the customer. To the outside. Right. Making money. So, um, if I’m taking a look at, say, a main bearing, I might see watts or kilowatts of losses. So you’re gonna have some ’cause you have friction, right? But when we see it increase on, say, a roller, [00:12:00] or the rollers, or, or the cage, that’s usually an indicator that I have a lubrication issue.
Or if we only see it on the outer race, that means that they didn’t clear out all the old grease when they were lubricating it, ’cause the rollers then have to ride across it- Right … ’cause it dries up.
Allen Hall: Sure.
Howard Penrose: Uh, and will carry contaminants. So if you see that, you go up, clean it up, you’ll extend the life of the bearing.
Absolutely you will. Without having to do a lot of work. So, uh, we, we look at our technology as more so early in the, in the stage of a condition. I don’t wanna call it failure, ’cause it’s not a failure. It’s something that’s mitigable. And I made that word up. You can mitigate it. Meaning you can go up and correct it and extend the life of that component.
Sure. Uh, in gearboxes we’ll see problems with, um… Well, the, the one we’re talking about here a fair amount is all the circulating currents going on uptower. We did that research. The current signature analyzer we have is a direct result of doing wind turbine [00:13:00] research just on circulating currents uptower, ’cause we conferred everything over to, to sound at 48 kilohertz.
And so that gives me a 24-kilohertz signal. That high-frequency stuff, which we’re researching in CGRE, and IEEE, and IEC, is called supra harmonics, which I– we talked about that before. Yes, we have. Yeah. And, uh, so when you start seeing that in the, in, in the current that’s circulating uptower because the ground that goes from the top of the tower down is for- DC
lightning protection. And lightning protection, yeah. It’s not meant for, um- Not for
Allen Hall: high frequency- Yeah …
Howard Penrose: currents. Yeah. Uh, we, when we measured it, when we mapped out dozens of towers of all different manufacturers, we found that the impedance about halfway down the tower is where it ends. Sure. The, the resistance.
And then the increased, uh, the high-frequency noise turns any of your shaft brushes into resistors. And at about 15 kilohertz, no current is [00:14:00]passing through them. It’s all passing the bearing, which becomes more conductive the higher the frequency. So with 60% of main bearings failing due to electrical currents, it’s actually currents that are circulating uptower.
It’s not static. There is some static up there, but it’s not static. It’s coming from the controls, the, the generator, and everything else. Inverters,
Allen Hall: converters.
Howard Penrose: And we’ve seen up to 150 amps passing through a, through a bearing.
Allen Hall: So I– We run across a lot of operators who have been replacing main bearings, and they don’t know the reason why.
Yeah. And I always say, “Well, call Howard at MotorDoc because I would almost bet you you have the f- high frequency running around uptower in the nacelle- And the next main bearing you put in there is gonna go the same way as the- Yeah … first one you put in there. Until you cut off that circulating current and then the cell, you’re just gonna continue with the problem.
Then you haven’t eliminated the problem, you’re just fixing the result of that problem. Yes. But it takes- Yeah, you’re, you’re- How, [00:15:00] how, well, how long- You’re replacing
Howard Penrose: a fuse.
Allen Hall: Right, you’re replacing a fuse. Yeah. How long does it take you to s- to determine- An expensive fuse. Yeah. Yeah. Oh, yeah, ’cause you’re taking the rotor down.
Yeah. Well, how, how fast can you determine if you have harmonics uptower that are gonna be causing you problems? 120 seconds.
Howard Penrose: Okay.
Allen Hall: So that’s the thing. I think a lot of- I mean,
Howard Penrose: that’s of the actual data collection time. So you clamp on uptower, uh, and then you can… Well, the way we have it set up now, you just tell it you wanna collect data every five s- uh, five minutes, and then you go downtower, let it collect its data, go back up, grab it.
Um, it’s like…
It’s huge. It’s this size. So, um, and then you connect- It plugs into a laptop. Yeah. Plug it into a laptop or any type of tablet. Um, it, it’s Windows now. I’m trying to get away from Windows. We’re gonna have Linux systems, uh, as well. Uh, and then you use that to, um, just collect that data, and then you press another button.
Now it pops up, and it tells you if you’re in danger or not, [00:16:00] the amount of current passing through the bearing, and the frequencies all the way out.
Allen Hall: So the ideal is you’re gonna have this kit with you in the truck. Yeah. And as you see these problems pop up, you’re gonna clamp on uptower. Yep. You’re gonna measure these circulating currents, and you’re gonna know immediately if you have another mechanical issue, a, a lubrication issue- Oh, yeah.
It’ll look at- … some kind of alignment issue, or- You’ll get all
Howard Penrose: of this information at once. So you- Right … if you go on the power side. So certain turbines, like anything that has the transformer downtower, you don’t have to climb. Right. GE. I mean, I don’t climb. So, uh, uh, you know, th- and that was part of the, the concept behind when we started down this path because I’ve been in the wind industry since 1997.
So one of the things I always saw was, and, and we talked about even, you know, here when it was called AWEA, and we were talking always on the health and safety side about wearing out the technicians. Um, so we discovered that, you know, what was it? Almost 60% of the [00:17:00] turbines you didn’t have to climb. Right.
Oh, yeah. And even the ones you do, you go up, you set it up, and it’ll tell you where you need to focus. The other thing in the powertrain, let alone the generator, when we do a sweep of a site– Now, if we do a straight electrical signature analysis, I’d term that one as a technician’s tool. Sure. That’s more of an engineer’s tool.
Uh, a lot more data, a lot harder to set up. But even though I’m saying harder to set up, it’s still pretty easy. It’s still minutes. Right. Yeah. Most technicians will collect data with, like, a couple hours worth of training. Yeah. You g- You basically gather that data, and if you’re getting a site, so we’ll go out– I love going out in the field.
So we’ll go out in the field, especially if it’s a tower we don’t have to climb I’ll knock out, uh, well, let’s just say I’ll, I’ll, I’ll name one. Say a GE 1.6. I’ll knock out one of those every eight to 11 minutes, depending on how you get to the tower.
Allen Hall: So that’s a full diagnosis of drivetrain- Yeah … plus anything odd happening- Yep
with circulating currents and all that [00:18:00] can- Oh, no, no. Circulating- Or just- … current, that’s a- That’s a separate thing at tower … separate study that- Okay … you have to do that uptower. But anything, anything drivetrain-wise, you can be in and out- Yeah … in a couple of minutes. Yep. Okay. So there’s a lot of operators that have end-of-warranties coming up, right?
Yes. There’s been a lot of developments, so they’re kind of running into the end-of-warranty, and they don’t know the health status of their drivetrain. Same thing for a lot of operators that are in- Yep … full service agreements, and they’re questioning whether they’re getting their money’s worth or not.
Yes. I always say, “Call Howard at Motordoc. You guys can have a whole site survey done maybe in a couple of days, and you will know all the problems that are on site for the lowest price ever”. Yeah. It’s crazy how fast you can do it and how accurate it is. I talk to operators that use your system, so I hear you.
Yeah. Your podcast, listen to your podcast, I’m calling your customers to find out what they say, and they love it. Oh, yeah. They can’t believe how accurate it is. Yeah. Well, the thing about that is we as an industry need to make sure that our turbines are operating at [00:19:00] maximum efficiency. Yep. And if a simple tool like the Motordoc EMPath system exists, we need to get customers, operators in line to start doing it worldwide.
Australia- Oh … Europe-
Howard Penrose: Yeah. We- … Canada. Australia, we’re trying to get into, but right now we even have OEMs using it through North- That’s good … and South America, Asia. Good. Uh, Middle East, um, and, uh, and some of Europe. Good. So it’s, it’s, it’s really taking off. Uh, I’d say probably our biggest market right now is Brazil.
Sure. They’re going crazy. Well, the, the turbines are- They’re having a lot of problems. Yeah.
Allen Hall: Right. And the, well, those turbines have a h- high usage, right? So because- Oh, yeah … the winds are so good, they’re operating at, like, capacity factor is above 50%. Yes. It’s insane. Yeah. So there’s a lot of wear and tear.
There’s no downtime for those turbines.
Howard Penrose: Yeah. Well, and, and people think it’s all the starting and stopping. It’s not. No. It’s a grid-related issue. So we have- Sure … we have a low frequency. And you know some of the stuff I volun- I, I’m, I’ve been volunteered for- [00:20:00] Yeah … uh, including the CIGRE thing. Um, so I get to sit in the grid code committees for IEEE and put my, and our input into that, uh, and kind of watch the back of the IBR industry, right?
Mm-hmm. ‘Cause there’s a definitely bias against our industry. Um, and I also, uh, get to hear what’s going on in the grid side of things from CIGRE worldwide, and it’s all very similar, and it has to do with low-frequency oscillating currents- Yes … called subsynchronous currents- Yes … which are low enough not to damage large synchronous machines.
And they thought, and there’s books written on this, by the way, multiple books written on wind turbine impact- Uh, and they’re seeing now, um… Well, we detected it first, along with Timken. Hank, uh, and, and I went out to a site, and we detected for the first time, because of how they wanna do the testing and where the site was located, we saw the oscillating torque [00:21:00] in the air gap, ’cause that’s one of the things the technology does.
It actually measures the torque, air gap torque. Sure. So we were watching the oscillating torque as a tower started up. And so we did, we went through the rest of that site looking at the same stuff in the same way. It increased our time and data collection, and time on site. But then we started looking for it at other sites, and going to pass data because I don’t have to go back and retake data.
Right. And we’re like, “Oh my God. It’s everywhere.” 16 hertz, 21 hertz, and 50 hertz. And we found a paper that specifically identified that as the sub synchronous frequencies for 60 hertz. So we know what they are also for 50 hertz. Once we identified that and we saw how much the torsi- torque was oscillating, we worked with Shermco, who got us some information on Y-rings that were failing.
Yeah. And they were all failing… When the metallurgy was done, they were all failing from fatigue. And you’re like, fatigue how? What’s fatiguing these connections? [00:22:00] Well, the fatigue is that air gap torque- Exactly … because you’re basically causing the, the, everything to oscillate a little bit, and that causes the windings to move slightly.
It’s a living,
Allen Hall: breathing machine-
Howard Penrose: Exactly … this generator
Allen Hall: is.
Howard Penrose: Yeah.
Allen Hall: It’s not
Howard Penrose: static. It’s definitely not sta- no electric machine is static. No. Even a transformer’s not static. Right.
Allen Hall: So- There’s a little
Howard Penrose: bit of wiggle going on there all the time All the time. And it’s minute, so it takes a long time. Right. And what, uh, uh, everybody…
Well, first people thought it was a particular manufacturer, which it wasn’t. Turned out every defig’s failing the same way. Sure. You’re fatiguing it. Yeah. Every bearing is failing the same way, even in the gearbox, main bearings, and everything else. Right. All of these conditions are happening across all the OEMs, but they’re not allowed to talk.
Well, this is, this is the thing that
Allen Hall: I like watching your podcast.
Howard Penrose: Yeah.
Allen Hall: The Chaos and Caffeine. It comes out Saturday mornings. It’s on YouTube. If you haven’t- Yeah … clicked into it, you should click into it
Howard Penrose: because a lot of these issues are discussed there. It’s definitely, um… [00:23:00] Let’s just say I’ll speak Navy quite a bit.
Allen Hall: It’s a great podcast, and I think what you’re doing with the EMPath system- Yes … at motor dock is really a game changer. Yeah. I’m talking to everybody, all the operators I know. I keep telling them to call you and to try the system out because it’s so inexpensive and it does the work quickly and efficiently, and it’s been proven.
There’s no messing- Oh, yeah … around when you’re talking to MotorDoc. I…
Howard Penrose: Somebody dared tell me that there’s no standard for it. There’s ISO standards for it. Yes. There’s IEEE 1415- Yes … which I chair. Uh, and there’s other standards coming out- This is- … associated with it. And there’s a document that I also chair for Sea Gray- Called A178, which is the practical application of the technology.
So it’s well-documented. There are traceable standards for it. I need more
Allen Hall: operators to call you- Yeah … and to talk to you and get systems in the back of the trucks that they can use to check out the health of their gear boxes and their drive trains and their generators. How [00:24:00] do they do that? Where do they go?
Where, where’s, what’s- Well- … the first place they should look for?
Howard Penrose: Uh, info@motordoc.com. Okay. I get all, I get all of those as well, so do my people. Um, or, uh, LinkedIn. LinkedIn’s really good.
Allen Hall: Look up anything. Yeah.
Howard Penrose: Yeah, yeah. So, so either the company at Motordoc, or, uh, I’m, I sh- I’ll show up either searching for my name or, uh, linkedin.com/in/motordoc.
Come straight to me ’cause I’ve been in, on LinkedIn forever, so- Right, just- … I got to do that … look up
Allen Hall: Howard Penrose, P-E-N-R-O-S-E. Yep. Or go to motordoc.com is- Yep, motordoc.com … the website address.
Howard Penrose: Yep. There’s a lot of great information there. And we have partners, and we have people. We’re growing the company.
You know, talk to me. I, I’ll- Yes … I like answering the phone and talking. It’s, it’s a thing. My people go, “Can we answer the phone one?” No. Um, but, but yeah, we, we, y- when you call us, you’re not just dealing with a single person. Right. The Motordoc is far more expansive. Right now, we [00:25:00] just got our partnership with, uh, Hitachi and, and Juliet- Yeah, that’s great
and stuff like that. Uh, we’re helping them with certain things. Uh, we’re partnered with some of the big OEMs, almost all of them, um, you know, helping identify the issues, you know. And, and when users contact us, often they’ll tell us what’s going on, and we’ll, we can, uh, sometimes say, “Yeah, it’s this, and here’s how we prove it.”
Allen Hall: Yeah. That’s the, that’s the beauty- Yeah … of calling Motordoc. So I need my operators that, that watch the show- Yeah … worldwide, go online, go on LinkedIn, get ahold of Howard, get ahold of Motordoc, and get started. Yep. Howard, thank you- And- … so much for being on the podcast. Yeah. This is fantastic. I love talking to you because-
it’s, it’s like talking to, you know… Uh, no, really, it’s talking like someone who’s a real good industry expert, who’s been there a long time, and understands- Yeah … how this
[00:26:00] works.
Sad that it came to this, but not nearly as sad as I would if he gets away with all this criminality, and the rest of the world writes us of as avid supporters of crime and apathetic to rule of law.
At left we see illustrated the core problem with the world’s theistic religions, i.e., that adherents are so certain of the rightness of their beliefs that they have no problem destroying the world.
FWIW, I have a friend who takes this even further: he is actively rooting for the apocalypse, and the prospect that all believers in God’s son Jesus will be raptured up to heaven to sit at the right hand of God.
He knows that I don’t believe any of this, but he remains confident that I’ll come around. As he told me, “God melts even the hardest of hearts.” He thinks I’m doing the devil’s work with my compassion for others and the effort I put out to achieve a peaceful and sustainable civilization.
We’d be living in tough times even without these fanatics, but religious dogma, especially of this sort, makes it all that much more difficult.
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