 It's one o'clock on Tuesday, February 8th. So you must be watching Science at Soast. I'm your host, Pete McGinnis-Mark. And every week, Science at Soast showcases some of the research which has been done by our graduate students and postdocs. Soast stands for the School of Ocean, Earth, Science and Technology. And there's many different aspects of the research which we're trying to cover during this semester. This week, we're dealing with the oceans and I'm really pleased to welcome Nick Olm, who is a graduate student in our Ocean Resources and Engineering Department. So Nick, welcome to the show. Thanks for coming. I think the discussion topic today is going to be on wave energy. And of course, that's a really important topic for State of Hawaii. We're trying to go renewable in the next few years, as well as a lot of us go in the ocean almost on a daily basis. So first of all, can you just tell us a little bit about yourself, your graduate student? How far are you throughout your degree program? Yeah, I'm midway through my fourth year. I'm hoping to graduate this coming December or the following spring, depending on how everything goes. I am doing my PhD on non-power grid applications of wave energy, specifically for ocean-observing applications and recharging autonomous underwater vehicles. OK, that's a bit of a mouthful. But it sounds as if you're not trying to put kilowatts into the power grid for HECO. And the autonomous vehicles, I would guess, is a number of sensors which are floating in the ocean, something like that. Yeah, so in order to properly determine, for example, the intensity of a hurricane, you need to know a couple of things about the top layer of ocean that you have and how much heat is stored in there. How is that heat moving? And so current methods, we use anchored buoys that sit in a single location. And you kind of hope that the buoy is within your hurricane path. The objective is to make it such that you have a set of these buoys that function as sort of a lookout. And they're able to get a lot higher resolution data in terms of your space and your time, such that we'll have better tracks of the intensity and severity of hurricanes that could hit our islands. OK, so just this one application, which you've introduced us to, shows the relevance of the kind of work that you and the department within SOAS is actually doing. We'll have direct relevance to people here in Hawaii, correct? Oh, most definitely. And wave energy is a topic that I'm particularly passionate about because it has so many applications to the state of Hawaii yet. Growing up here, you see a lot of the problems with being the most geographically isolated place in the world. And so you need to come up with a lot of solutions here locally for local problems instead of importing a lot of these technology solutions. And of course, the surrounding ocean is massive around the state of Hawaii. So having sensors or instruments way out shore, presumably, is a really important thing because otherwise, you wouldn't collect the data, right? Exactly, exactly. OK. All right, well, I'm sure most of the people are familiar with seeing surf on the North Shore of Oahu, for example. But I understand that in the first slide, if Michael, you can just show us the first slide, there are different types of waves. And so Nick, can you just lead us through? You've got three different types of waves labeled on the top of the illustration, but what are they? Yeah, so when we talk about waves, what first comes to mind typically is this breaking wave that you see in the top right corner there, that plunging breaker. But that's not how most waves look on the ocean. And that's not what we mean when we're talking about wave energy and capturing energy from waves. What we're really talking about is this swell and these wind waves. So swell is typically your longer period, longer length waves that you'll see. This is the stuff that is really great for surfing. And when you look out on a pretty calm, not windy day, you can sometimes see these long crested just lines coming towards the islands. That's what we're talking about when we're talking about the swell. Now, when we're talking about wind waves, those are waves that are generated locally. So the wave that waves are formed from a sort of philosophical standpoint, waves are condensed solar energy. So the sun unevenly heats up the earth and you have this pressure differential which induces wind. And when that wind is traveling across the ocean, you end up having some of that energy from the wind transferred into waves, which is what you get with the locally generated wind waves. And I understand that you're a surfer, but it would be the breaking waves which the surfer would be familiar with as opposed to these long wave length swells and that kind of thing. And then there's some terminology at the bottom part of our first diagram, let's just walk us through this. Obviously, surfers would be familiar with some of the terms, but landlocked people may not. You have a couple of characteristics to kind of talk about. You have a crest, which is the high point of a wave. You have the trough, which is the low point of a wave. You have what's called the wavelength, which is a little bit self-explanatory. It's the length between crest to crest or trough to trough, depending on how you're measuring it. We typically do crest to crest. And you have your wave height, which is the overall height of the total wave rather than just the amplitude of the wave. And so when you're talking about how you calculate the energy, you do it in reference to these specific metrics. All right, and particularly the image of this ocean wave swell. When we're thinking about the wavelength or the wave height, they look pretty small in the photograph, but presumably they can be quite large, right? Yeah, yeah. And I mean, if you look at the wave energy test site on the kind of a marine core base, just recently we had a set of 80 to 100 foot open ocean waves coming through. So they can be quite large. Okay, that's wavelength, not height, presumably. Sorry, no, that's a wave height. Wave length will be much longer. And wavelength is directly related to your wave period. So the wave frequency is directly related to the length of your actual wave. Okay. So how much energy is out there? I think your second slide actually shows us a global map. I was amazed when I saw this illustration start off with. So presumably we're seeing the globe here with the continents in white, but what's the rest of it show? Yeah, so the rest of it is showing sort of your energy density, this kilowatt, which is your power per meter wave crest. So when we're talking about per meter, we're talking about actually the width of the wave, not the length of the wave. So the wider your device will be the more energy that it can capture because it's able to get more of that wave crest. And so what you're really seeing here is an interesting distribution. And I think that you and the audience can kind of clean this, that we have a higher density of wave energy towards the poles. And this is getting back to this fundamental and philosophical viewpoint of energy and energy transfer is, where do you have the most turbulent conditions? Where do you have the most violent storms? Well, if you think of Oregon during the wintertime, you have people who are storm chasers who will go up and live right on the coast there just to see these massive waves slamming against the coast. And that's actually... And this map would hint that Hawaii is fairly favorably located. Yeah. Where there's orange and dark red there, pretty close to where the Hawaiian islands are. Yeah, we're kind of this medium wave condition where we're straddling between this really high energetic seas and sort of the calmer seas of the equator region or equatorial origin. And now... Yeah, yeah. Now, will people be interested in the middle, say at the Atlantic or off the coast of Antarctica? Is that a viable place to garden wave energy or would you really want to be close to where people live and... It depends on your application. So fundamentally with wave energy, you're just producing power and what you do with that power is the real kicker. So you can use it coastly and to power residential power, commercial power. But for example, if we're trying to understand the Southern Ocean, you don't have a whole lot of energy options out there in terms of solar energy. You don't have that consistently year round. So if you're trying to do something like observe the Southern Ocean, you really need to be able to produce power on site but not rely on solar power. Your solar power really starts to attenuate off outside of this tropical and subtropical zone and you can't rely on it year round. And so one thing that we're interested in is, and I think the Department of Energy is interested in is how can you use wave energy to observe some of these colder regions outside of the subtropical zone? So it's probably worth reminding the viewers that when we're talking about wave energy, you aren't competing with HECO for many of your applications. This is to sort of provide power where small instruments, perhaps are floating around on the ocean surface from hundreds of miles away from land and you can't use solar power. So you have to get energy from some other source. Exactly. And what options do you have out there? Well, you have battery power, you can have a diesel generator and have to carry around a bunch of fossil fuels, which can be quite expensive. So that's why wave energy and wind energy are two really interesting areas to look at. But outside of just ocean observation, there are other applications. So open ocean, what other market activities are done? Well, within the state of Hawaii, there's this massive marine aquaculture industry, the marine fisheries industry. And so how do you effectively do marine fisheries management? The current methods use these fish aggregating devices and buoys where they'll have an echo sounder, they'll have this acoustic way of measuring that amount of fish that are underneath them, but they don't know what the type of fish is. They don't, well, you can glean what type of fish it is. You can glean what depth it is, but you don't know nearly enough information to do targeted fishing practices where you're able to really meaningfully reduce your bycatch and be able to not target these endangered species. And so that's a real issue of concern. So one could infer that there are different types of instruments that employ wave energy. I think your third slide is gonna show us that there's a wide variety of different types. Yeah, here again. Yeah, can you just walk us through Nick? There's six examples here. I know that there are others, but very briefly, A to F, what kind depends on the view you're seeing? It really depends on your application. So what depth are you at? How close are you to shore? We'll determine what is maybe a preferential way to extract energy. In example, A here, you have what's called an attenuating device. And the way that that functions is you have two bodies that are floating, kind of like barges that are hinged together. And the relative motion between those hinged bodies as a wave will raise one side or straddle the other will go and induce this relative motion that you extract power from. In example, B, you have what's called a point absorber. And the way that this functions, yet again, relative motion between two bodies, two floating structures, you have an outside ring float that will go and heave relative to a central spar and you'll have a set of coils and magnets where you're able to generate power. In example C, you have what's called an oscillating water column. Think the hole on a bull hole over by Sandys or if you were to take a bucket and poke a hole in the top and push it down in a pool. If you were to put a fan on that little hole there, now as the wave is compressing that air, you're able to extract energy from the moving air. Example D, this is an overtopping device. So the way that it works is as a wave hits this large structure, you have some of the water overtop into this pool and the relative height difference, similar to how dams work, will have the water flow down through a turbine and generate power. And E and F are a different example of a point absorber. So you can have sort of this reaction plate where you have a buoy that rises and falls relative to, instead of a second body relative to the C4 or an example F, you have sort of this rotating mass where now as the buoy is shifted to one side, you have a mass inside that goes and will want to correct and will adjust turning this generator. So what kind of sizes are they? Are they like a laptop computer size, the size of a Volkswagen Beetle or a 10-story building, order of magnitude, how big? It depends on, yet again, your power application. If we're talking about commercial power grid, we have a device that's located at a lot of tower. It's produced by a company called Ocean Energy and that one is another oscillating water column type. That one is 35 meters by five meters by eight meters, which... About 100 feet across. Yeah, that one is meant to be a 500 kilowatt producing device, which is a sizable amount of energy versus, well, if you're wanting to power some oceanographic sensors, your buoy can be seven foot by seven foot by eight foot in size. So it really depends on your application. And it must be a hostile environment out in the open ocean. How long do some of these things, what's their life expectancy? That's one thing that we're really looking into and I think that a lot of devices haven't had sort of these multi-year tests. In most cases, there'll be anywhere between three and 12 month deployments that you'll go in because the technology is still relatively early in comparison to offshore wind and solar, but we're definitely getting there. So roughly a year might be a good expectation for summons. Yeah, and obviously because it's such a hostile environment, you'll want to do inspections more frequently. There's a lot of things to consider. This is a floating structure. You need to make sure that the hull is buoyant and hold in water. There's the energy extraction portion of it where you need to make sure that the mechanical parts are functioning, some things break because of just the cycles. And then of course there's, how do you have this anchored to the bottom? Is your mooring line going to hold? And the mooring lines, those typically last a lot longer than what we've deployed the devices on. Great. Now, before the show, you gave me an example which I found really exciting that you might be able to use wave energy for desalination of water. I think the fourth slide. I mean, this sounds really exciting for emergency relief. Can you explain a little bit about what we're seeing here? Yeah, so this was for a Department of Energy competition that the University of Hawaii participated in with Indian Institute of Technology in Madras. And this is supposed to be a disaster relief scenario where you have a wave energy converter that packs into a three foot by three foot by four foot box and you ship it to say an island community that's been hit with a hurricane and within 48 hours deploy this and it's producing fresh drinking water within an acceptable tolerance. And we use this very large flap. It's called an oscillating wave surge converter. That's the topic, right? Yeah, imagine that you have a syringe and your thumb. The thumb is this large paddle and it's as a wave hits the paddle, it depresses it and it forces a pump to directly pump water through this desalination filter, a reversed osmosis filter. I see. And it's a little small in the diagram but it looked as if there was a pipe leading out of the bottom of that white box. So it provides fresh water continuously as opposed to you have to send a scuba diver to pick it up. Exactly, you can pipe it directly to shore and these devices, like I said before, it depends on the depth. These devices directly take advantage of the horizontal motion of waves. If we go back to slide one, you have this vertical and horizontal motion to waves. Waves fundamentally are the transport of energy rather than of water. And so if you were to follow a water particle in a wave in an ideal condition, it would move in a perfect circle. But anyone who's gone surfing can kind of understand that that's not how a wave works in the shallow water environment, in a near shore environment. It becomes squeezed and it becomes a lot more of this lateral horizontal motion. And so this device is ideal because it is deployed in a shallow water environment and is designed to capture the most out of that lateral motion. It would sound an ideal kind of a technique to send out to Tonga, for example, following the recent volcanic eruption and disruption. Yeah, yeah. Do you know of any other examples of this being used genuinely for relief work or is it still in the development stage? Yeah, so we went through the development phase. Unfortunately, in that competition, the competition site that they chose was not well-suited for our device. And so we didn't continue on in the competition. But we're looking to actually start building this prototype and testing it in a tank facility. It's definitely not at the point where we can mass produce these and send them off to emergency disaster relief scenarios right now. This is being done in your department at SOAS at UH Minoa. Yes. That's terrific. And I think your fifth slide shows some other kind of floating device. Yeah, yeah. That hurricane monitoring device that I had talked about at the start of the show. So this is what my dissertation focuses on. And it focuses on a device that extracts energy very similarly to the Halona Bull Hole. And it's called Halona for that exact reason is that we started off looking at, okay, the Halona Bull Hole has this interesting resonance property. What about the Halona Bull Hole makes it such that it spouts off like that? And can you... Why is it resonance? That's the function of... Exactly. It's resonance. And so we... Which means what? Which means what? It's occurring on a regular basis. Yeah. So for a specific wavelength and a specific wave frequency, if you were to have, let's say a three-foot wave, you might see an example where you don't have a turbine up to nine feet of change in that water level inside just because it focuses all that wave into a single point. Okay. And this is your PhD project, right? So the instrument, again, how big is it? Is it sort of a little small thing or... Yeah, the device depicted, it depends on your power application again. So for roughly the magnitude of hundreds of watts, this device is smaller than an eight-foot by eight-foot by eight-foot profile. Not exactly allowed to give all the dimensions because this is a... Yeah, yes. But overall... Are you physically making this? I mean, is it something that you go into an engineering lab and you've got a lathe or something which is cutting metal and putting it together? Is that what you do as a grad student? So that's the end goal. And that's what we're preparing for. Actually, we're looking to go and test through this testing infrastructure in May, this size device. But previously, you don't jump immediately to this full-size device. So you start off in a bathtub. You start off in a small pool of water and you make it one to 20th size, one to 10th size, one to 50th size. And you test it in a controlled environment. So you can know, okay, this is fundamentally how it works before you throw something in the ocean that you have no understanding other than what you've done on a computer. Now, you mentioned that you grew up here on the islands. I'm always interested. How did somebody get excited about this particular type of work here? What did you do for your undergraduate work and why for your PhD? Yeah, so it started off when I was at Johns Hopkins. I knew that I wanted to work in either renewable energy or aerospace. And unfortunately, I got really sick my freshman year and ended up not doing too well in a couple of courses, but it forced me to stay back in Baltimore. And I was introduced to a company there that worked in Wave Energy. And that just kind of set me on that path where I started on one wave energy project and then ended up doing an internship here at the University of Hawaii. And as I was finishing my undergraduate degree, I was applying to all of these different companies and they kept telling me, go back and get your grad degree in ocean engineering. Go back and get your grad degree. And so I was going and applying for different programs and the University of Hawaii's ocean engineering program is one of the top. And it doesn't make a whole lot of sense for me to go to someplace that's cold and isn't as beautiful when there's a perfectly good option here in the state of Hawaii, being back home. Okay, so do you take a lot of engineering courses or do you go out on research cruises? Yes. It's an interesting department that you work in that seems to mix two or three different topics. Yeah, yeah, so you start off with your fundamentals of how waves work, basic oceanography for ocean engineers, floating structures, coastal sediment transport, if you're wanting to do harbor design. And we have a lab class where I was privileged to go out on a research cruise with Dr. Bruce Howe where we went to the Lahakia Observatory. That's the Observatory 60 miles north of Oahu here. So we got some ocean time. You get to do a lot of hands-on work. I was trained in scientific diving. So it's been a real privilege. And what are your plans? What are your plans? You're less than a year out of graduating at any job prospects or what would you like to be doing this time next year? I'm an entrepreneur and I've started my own company kind of on a very similar note to all this wave energy research that I've been doing here. And my objective is really to have the wave energy community here from a private sense grow. So I want to go and work on my company. Oh, terrific. So how difficult was it to start a company in Hawaii as a student? Well, starting a company in the state of Hawaii is actually surprisingly easy. You can do it in 30 minutes. The process of figuring everything out is the kicker. And it's been really interesting being at the University of Hawaii because there's the PACE Business School, which has the Entrepreneurship program. And I've gone through some of their summer seminars and their business plan competition, which has really helped me in terms of preparing for this. OK. So the prospects are good leading on into 23. Is it a niche market? Are there many other students doing this kind of research? Or are you on your own? We've got a growing lab. Since I started the program, we've expanded as a lab to include, I think now we're up to this coming semester. We're going to have five graduate students. So it's getting a lot of traction. It's getting really exciting. I mentioned earlier, Nick, that you're a keen surfer. And unfortunately, we're running out of time. Otherwise, I would have drawn the connection between surfing and wave energy. But let me just remind the viewers that you've been watching Science at Soast. I have been your host, Pete McGinnis-Marc. And my guest this week is Nick Orm, who's a graduate student in the Department of Ocean and Resource Engineering. So Nick, thank you very much for coming on the show. Good luck with the PhD defense and good luck with the company as well. So with that note, thank you for watching and we'll see you again next week. Goodbye.