 Thanks a lot. Thank you, and thank you all for coming. I really appreciate the opportunity to share with all of you our vision for next generation wind energy. Now, for us, next generation wind energy comprises a new type of technology that can harness the wind anywhere on the Earth. And if you look at a map of the wind around the world, you'll see that this is actually quite a tall order. So here you can see a plot of global winds around the world. Those colors from red to yellow to green are areas where the wind is sufficient to generate meaningful electricity. And so with just a few exceptions, heavily forested areas like the Amazon, the Congo, and Central Africa, the wind is truly globally distributed. And so that provides us an interesting opportunity that I'll describe today. Now, we can contrast this, for example, to coal deposits, which sit under less than 5% of the land area around the Earth. And so we think of wind energy and other renewable sources as potentially democratizing the way that energy is distributed and consumed around the world. The first opportunity this presents, then, is one of the big challenges I think we face as a society. And that's the 1.4 billion people without access to electricity, many of them living in areas with very healthy wind resources. There are hundreds of millions more who might have limited access to electricity but at very high economic, environmental, or cultural costs to that energy. And so what I want to describe today are technologies that I think can make a large dent in that 1.4 billion. Now, in addition, here in North America and in the developing world, there are literally trillions of watts of power in the wind that are inaccessible to current technologies due to a parameter I call resource, patchiness. Now, this patchiness you can kind of see just by looking at this wind map here. You can notice the colors are not uniformly even anywhere. There's this sort of fractal nature to them. And in fact, if you were to zoom in, for example, on Northern Los Angeles County here, this is an area where we've conducted a lot of our research and I'll be discussing some of the results from this segment. You can see again that the wind resource tends to be patchy. And some of that has to do with the fact of local terrain. There's some foothills in the area that tend to channel the wind in certain directions. Some of the patchiness, though, is due to the built environment. Once we build our buildings, our homes, we plant trees and so on, that changes the character of the wind energy so that it has this patchiness to it. Now, in this particular case, these areas here again in red and yellow and green are all areas where, in principle, we could generate meaningful wind energy. And yet here I can show you the places where we can actually put wind turbines. That's a very limited section of this and the rest of this area is inaccessible to current technologies either because of the local terrain, because of environmental conflicts with birds and bats, or because people simply don't want to see the large turbines close to the built environment. And so what I'll talk about today are new technologies that we believe can address this limitation. Now, the other type of resource patchiness is one you might not necessarily think about, but right in the middle of our existing wind farms. So this picture here comes from the North Sea and you can see here, this is now a classic picture in wind energy. The wind is coming here from the bottom of the image. It's interacting with this first row of turbines and on this particular day, the fog helps to highlight the turbulence that's created by the individual turbines, the choppy air that results from that interaction. And because of that turbulence, all of the rest of the wind turbines in the field, instead of seeing a nice smooth air, which they were designed for, they see this roughed air that reduces the efficiency of the turbines, so how much energy they can capture. But it also reduces the lifetime of all of the components. Think of a paper clip, you bend it back and forth and back and forth and it snaps. The same thing happens for these blades when they're completely, when they're cyclically loaded over time, they can fail. And so today, the best thing we know to do to address this issue is to put the turbines as far apart as possible to avoid those turbulent interactions. But as a consequence, we end up with these big gaps where we're not able to extract energy from a wind farm. And it is true in some cases, we might be able to pursue agriculture or other uses. But in most of the areas around the world, this is simply wasted energy. And so again, what I wanna talk to you today about is a technology that will allow us to reclaim that lost resource potential. Now, at the end of the day, the question that we're gonna have to come to grips with is the cost of the energy. If it's too expensive, regardless of how clever the engineering is, it's simply not going to have an impact. And one of the standard ways we think about this is through what's called the levelized cost of electricity. How much money does it cost for a certain unit of energy that's produced? Now, the challenge in coming to a good number for this parameter is that we have to assume things about, for example, the system lifetime. Will this work for 20 years, for 25 years, 30 years? We have to have an estimate of operations and maintenance costs for the system and so on. And so what I wanna talk about today is something that's a bit different but closer to the physics of the problem. And that's what you could think of as a capital cost. So how much money does it cost for the average amount of power that my system can produce? Now, that average power produced, we can calculate relatively straightforward by three components. One of them is the wind power that's entering this wind farm. The second is what I call a total turbine swept area. So in that wind farm, how many wind turbines can I fit in the space? And then the third point is this wind power conversion efficiency. So of the energy that passes through each of those turbines, how much of that wind energy is successfully converted to electricity? Now it so happens if you go back over the past three decades in the field of wind energy, the focus has been almost exclusively on just that last term, the turbine power efficiency of the single wind turbines. And so if you were to make the comparison that I'll do today, which is to say, let's consider a current style wind turbine. These are known as horizontal axis wind turbines because the blades are rotating about a horizontal axis. And we're gonna contrast them with turbines where the blades rotate on a vertical axis. It's also the case, and this is sort of jumping ahead, but we're going to also imagine that we can generate energy using something much smaller. So instead of 100 meters, only 10 meters. Now, if I ask the question, what fraction of the energy that passes through that swept area, so the circular sweep of the conventional turbine, or in this case, it'll be a rectangular sweep, how much of that's converted to electricity invariably horizontal axis turbines are more efficient than vertical axis turbines. And in fact, today, there's nothing I'm going to tell you that's going to try to convince you that this is different. The point is gonna be that to get to low cost energy, this doesn't matter. That in fact, there's going to be more important parameters as I'll describe in a bit. But before we get there, it's useful to think about theoretical limits. We're scientists, we like to think about those concepts. Here I'm plotting the efficiency as a function of what's known as the tip speed ratio. Simply the ratio of how fast the tips of the blades are moving to the wind speed. And the interesting thing is that if you go back now 100 years almost, we've known that there's a theoretical limit called the Betz efficiency limit of about 59% for a wind turbine. How much energy a single turbine can extract. And if you look at modern horizontal axis wind turbines, and this state is actually a bit old now, they're approaching 50% performance. So almost getting to the theoretical limit of what we can do with individual wind turbines. And so it leads to this question of whether there are any real fundamental improvements left to be made in wind energy. This is very different from the case in solar right now, where we still see some interesting headroom with new materials to improve the efficiency quite significantly from where we are today. In wind energy for an individual turbine, we're basically at our theoretical max. And that's why you hear people suggest that wind energy is a mature technology as composed to research in solar or battery storage or other technologies. But we wanted to explore those other two terms. And remember when we talked about the average power produced, there's two other factors that you have to think about. One is the wind energy that's going into the entire farm. And the other is how many turbines we can fit in that region there. And so to think about this problem, we ask a slightly different question. Rather than asking about individual wind turbines and how much power I can get out, I ask about the wind farm. And of the wind that enters the farm as a whole, how much of that power can I extract? And those turn out to be very different questions. Now we need a little bit of physics here to appreciate the problem. So first of all, it's useful to note if we imagine the wind coming from left to right, there's gonna be an energy source that we'll call the frontal kinetic energy flux. So if you imagine yourself standing at the front of a wind farm, the wind is blowing in your face, that's going to be this source of energy here. And I've illustrated with these arrows the strength of the wind. Due to the friction with the earth, the wind is gonna be stronger at higher altitudes. And that's why we tend to see the wind turbines placed higher up in the sky. But there's a second source of energy that's going to turn out to be the important player in this question. It's what we now call a plan form kinetic energy flux. And I've sort of generically illustrated it as coming down vertically. But in fact, that's what happens. You have energy that's transported from above the wind farm into it. That turns out to be a key player in our story here. So this plan form kinetic energy flux. And these terms aren't too important, except to say that this term here is related to turbulence. So there's gonna be turbulence that's generated in this wind farm. And that's going to be important for drawing in energy into the array as a whole. And recent work using computer modeling has shown that in large wind farms, this is actually the primary source of energy for the wind farm. So after the first row or two, that frontal kinetic energy flux is already exhausted. It's this source that's going to be important for the large scale wind farm performance. Now that becomes important because then this becomes our real constraint on wind farm performance. The Betz limit that I talked about before, it told us what would happen for a single turbine. It didn't say what happens to the leftover wind power. And in fact, what I'm gonna talk about in a moment is how you can actually extract and recover some of that energy in ways that's cost effective. The other point that I would make when you think about the Betz limit is that it doesn't tell you anything in between the turbine. So this is a picture I showed you earlier. The swept area of the turbines, you could say, has something like 50% efficiency. That CP is 50%. But in between them, it's effectively zero. And so our perspective is that instead of spending millions of dollars in R&D, trying to go from 50 to 51 to 52%, let's do something about the big zeros that are in between the turbines. So we know this plan form flux is the important limiting factor for these big wind farms. How does that number actually compare to a theoretical limit for the system? So one way to look at this, this is a very busy plot, but I'll step you through it. One way to look at this question is to take a plot of energy consumption. This is per person, so kilowatt hours per day, per person in different countries. Here's the US here, Portugal, Singapore up here. So this is a log scale, 10, 100 and 1,000. We're plotting that against population density. So how many people are there per square kilometer in these different countries? And again, you can see where the countries sit here. So a country like Sudan has a lot of land area. It also uses relatively little energy, so it sits down here. A country like Singapore has a very high energy density relative to the other countries. Now the benefit of plotting this data here is that we can then compare with different renewable energy technologies. This is from a book by David Mackay. And for example, you can see concentrated solar power on average will get you something like 20 watts per square meter of the facility where it sits. Wind power, you can see here, sitting at two and a half watts per square meter. So per square meter of wind farm footprint, I get on average about two and a half watts of power. Now the interesting thing that he points out in this paper is if you pick a country like South Korea here, the fact that its dot sits up into the right of this line means with modern technology we could cover the entire land area of South Korea with wind turbines and still not generate enough energy to satisfy their demand. So from a research perspective, of course, the idea is to try to push these green lines up into the right. But what I wanna do is to go back to this question and we can theoretically calculate what that plan form flux was into these wind farms. And it's actually quite a bit higher. So something like 68 watts per square meter at eight meters per second wind speed. So there's a big gap here and it sort of leads to this paradox of sorts whereas we said the individual turbines are performing close to their theoretical maximum. We can't do any better in terms of the individual turbine design but in terms of the wind farms, we're sitting far below the flux limit. We have 68 watts coming in. We're only capturing about two and a half watts of that power. And so the gist of the story is that right now for modern wind farms the hole is much less than the sum of its parts and that's what we wanna try to improve through our research. Now this is not the only challenge you see with conventional wind energy as I'll call it. Again, if you go back to the premise we want this technology to capture wind anywhere. One reason we can't is because of the size and the design and materials costs associated with conventional wind turbines. So this is a scale drawing. This is a utility pole like you might see outside here a forest tree at 60 feet. They're significantly larger than our built environment and so that necessarily constrains where we can implement this type of a technology. In some cases it's the logistics of installation and maintenance that become limiting. So this is a case of a caravan going through a European town. In many cases today the limit on the size of the blades is getting underneath our overpasses in our highway system. It simply wasn't designed for technology of this scale and so that's another limit on where wind energy can penetrate. And then there are issues that you might say are more subjective but they certainly play into whether or not a project gets permitted. So me as an engineer I think these look really cool but people on planning boards don't always agree and that can limit whether or not a project ends up getting approved. The issue of bird and bat impact is one that we've faced ourselves. Maybe I'll comment on that later. But even things like acoustic and radar signature you've had cases where the FAA or the military have prohibited projects because of potential interference between the signature from the blades and the measurements that they need to do with the radar scans. So taking all of this together and this point here which is limited access in the developing world where there's limited infrastructure taking these together we've decided to take a different approach. Right now I would say the mantra in the industry is bigger is better. If you look at DOE's plans for where wind energy's going it's building larger wind turbines it's putting them offshore. There's very little thought to the question of maybe to go in a completely different direction which is to say using smaller systems and in particular for reasons I'll explain later systems that rotate on a vertical axis in optimized arrays. If this works it has potential advantages along many lines. First of all the smaller size of the objects means that the materials costs can be much lower. You don't need fancy carbon fiber systems to manufacture these because the physical loads the forces they feel are lower. You have of course smaller wind farm signatures and I'll show you an example later but you can't see them from distance you can't hear them the radar impact is minimal. Potentially simplifies logistics of installation operations and maintenance as you'll see later on at our research site we're able to maintain everything with a Ford F-150 pickup. So there's you don't need the very expensive and skilled operators required to operate and maintain conventional systems. Interestingly there's a scalability here that at least occurs on paper which is that if I'm a rancher and I just want 10 kilowatts of power versus a municipality that needs 100 megawatts the only difference necessarily is in the number of these systems you're not necessarily building a physically bigger structure. And so that what that means is if you get the engineering right for one of these you can multiply them potentially it's like a transistor if I need more processing I just put more of them in. And then lastly we and others have been monitoring this issue of bird and bat strike for a long time and of all the companies that are out there that are developing these there have been no reported bird or bat strikes. This is for two reasons one of course these operate closer to the ground so they're not going to be necessarily in the flight corridor but they also have this rotation about a vertical axis that has a different visual signature than the very fast moving blades of a conventional wind turbine. So these were all compelling reasons to us why we might pursue this but again the question you would ask yourself is you know can turbines operating only 10 meters above the ground wind speeds are lower closer to the ground as I said because of friction can they compete with systems that are 10 times their size? And so the short answer is going to be that we can compete by again making sure that the hole is greater than the sum of its parts rather than less than it. So how do we come to this conclusion? Well, Jeff told you earlier about my side passion of jellyfish which is kind of an odd animal to be interested in studying but it turns out jellyfish evolutionarily they're the first animals to figure out how to move through the water they're the most successful in terms of their longevity and so we've used studies of how these animals interact with the surrounding water to inform for example ocean monitoring developing underwater vehicles that can move through the water using 30% less energy than a conventional system or in the area of soft robotics so this was a fun project that we did with a group at Harvard this is a layer of PDMS, a thin polymer and we laid on top of this muscle cells from a rat's heart and so when you put that in an electric field and if you design those muscles to mimic the architecture of a jellyfish you can see here you can get your Frankenstein to swim here so why do we do that? Well partly because it's cool but also because it allows us for example to study the effect of different drugs on those heart cells and to have a very simple read out of the efficacy which is the swimming behavior that results from it so that was another example here in this case our story is not actually so much about jellyfish but other swimming organisms and how they can inform wind energy so the question as I posed before is can we make the hole greater than the sum of its parts? So yes the individual turbines are less efficient but by working together can they remove some of the disadvantages we saw in the current wind farms and our inspiration came from fish schooling where there are some interesting parallels between you can see these regularly swimming mackerel here so each of these fish is flapping its tails it's creating this wake behind it that in principle you might say the solution is to stay as far apart from one another as they can in order to move through the water it turns out if you measure the energy consumed by one of these fish to swim it's more efficient than this group interacting with the wakes of its neighbors than it is by itself so they've been able to optimize their interaction with the flow created by their neighbors such that the group is a more effective system moving through the water so in my class I teach a graduate course on swimming and flying in nature and this was one of the problems that we've studied for a long time it wasn't until maybe 10 years ago we made the connection to wind energy but there's a classic paper by Danny Vai as a colleague of ours where he studies the optimal configurations these diamond patterns of these fish and explains how the interaction of these swirling motions in the fluid can lead to this improved behavior and so we argued that if you were to look at a vertical axis wind turbine array from a bird's eye view so looking at it from the top and if you thought instead about the swirling motions created by the tail here you think about the rotational motion of these vertical axis wind turbines that there might be a parallel there and in fact as I'll describe later one sort of non-intuitive result that you might appreciate from this graphic is that not all the turbines should necessarily rotate the same direction so if you go to any wind farm today you'll notice probably for logistics and manufacturing purposes all the turbines rotate in the same direction for a horizontal axis wind turbine for the vertical axis wind turbine there's interesting ways in which you want these to be different from one another and so for the past five years we've been studying these concepts both in the laboratory but in the field at a site in Southern California down in Lancaster if you've ever been down that way it's about an hour north of the Caltech campus and I like this picture this is just about a half mile from our site you probably in the back can't see the wind turbines and that's kind of the point that they have a reduced visual signature relative to equivalent turbines that would peak above this ridge line here so they're sitting here the next clip you'll see some aerial footage from the site and the experiments that we were doing over the past five years so here's me for scale you can get a sense of how tall the turbines are in this particular test we were studying these pairs of turbines you can know it's how close the wind turbines are to one another relative to what you would see in a standard field and these black stumps here are 72 different positions where we could optimize the performance of the array by placing them in different locations measuring them under real wind conditions so we were able to understand seasonal effects find out what happens when the wind changes direction for example and build up a quite extensive data set on performance so this first data series that we collected for about four years was over 18,000 hours of field measurements sort of the first of its kind and really unique because most of the studies that you achieve these days are either computer models or wind tunnel studies it's very difficult to get full-scale field data and in fact one of the things that came out of this is that doing work in the field is really essential to pull out the underlying physics here but nonetheless here's just a graphic example of the different configurations and again looking from a bird's eye view the red and the blue indicate counterclockwise and clockwise rotating turbines so we studied a variety of configurations I just want to show you one example here this is for 18 turbines with a prevailing wind direction here which was coming from the southwest so the type of thing we're interested in measuring is this power density we talked earlier about the watts per square meter that you could get in a conventional wind farm as opposed to what you might get here so this is footprint power density watts per square meter versus wind speed and this is the envelope that you would typically see a conventional wind farm of 30 foot I'm sorry, excuse me, 300 foot tall structures operating in and here's data from just one of our campaigns as an example each of these data points are measurements in the field and so we're able to get significantly higher performance both due to the fact that you can put the turbines closer together but also in putting the turbines together we improve the performance of the individual turbines rather than reducing their performance as is the current case and so that has led to what I call a new school of thought I needed some sort of a fish school pun here so there it is GE for example is a company that I would say personally is pretty conservative as far as their energy group is and wind energy they're now advertising this concept for their own wind farms and so this is from an ad they have in the New York Times at the end of the year it says, ever notice how fish often swim in a tight spiral pattern it's no coincidence the basic idea helps when examining how wind farms might be arranged to maximize efficiency in a similar fashion thanks to smart connection and interconnectivity between GE turbines wind farms today also emulate the adaptability of fish schools so even today in the mainstream wind energy sector you're starting to see these types of ideas coming about but I will note that they're still doing it using the conventional horizontal axis wind turbine the reason is that even in these systems you can see benefits it's going to be something on the order of 5 to 20% which is actually huge if you're talking about a you know, 300 million dollar wind farm project but the thing that we're excited about is that in the vertical axis turbine approach to this problem it can be factors of 3 and 4 and 5 not 15 or 20% improvements that you can get by taking this type of an approach so this is one example of how this is caught on in our lab we've now been pursuing then a combination of basic research and development both on the Stanford campus here and also down in Lancaster, California we're interested in continuing to do this sort of optimization work but also testing distributed and hybrid microgrid concepts so Arun Mazumdar and others on campus are interested in the grid of the future and we see this as a very useful test bed for thinking about the combinations of wind and solar and diesel, hydro that are going to be used to get away from the current energy portfolio that many countries have and we've combined that with an area that I'm really excited about we call it our sort of living laboratory test bed in Southern California we have the wind turbines connected to a battery bank and then heaters to dump the power so basically just heating up the desert we thought it better to have a facility where the energy is actually being used by people who need it and so this facility here is one that we started developing about two years ago that allows us to look at high penetration clean energy systems in the real world this village and I'll show you a video clip in a moment is taking advantage of wind energy but also hydrokinetic systems because there's a river that runs right next to this particular village we're able to do things like monitor avian impacts acoustic impacts, other electromagnetic signatures energy efficiency is an important piece of this because in some cases it actually is smarter to better insulate your building especially when you're in Alaska than simply pumping more heat into an inefficient building so we think there's some interesting nexus there with energy efficiency and smart grid tech and then another piece of this puzzle that those of you who are interested in coming from it at a policy or cultural perspective it's important that we also find a way to engage the local communities that this is not some technology that's airlifted drop down and boom you're done the communities have to become engaged in this and so that's been an important part of the work we're doing in the village so I could go on but in fact we've had a documentarian in the village taking some video of the progress on this project and I wanted to show just about a four minute clip from that so you can get a sense of how this fits into the village and where we're going so that's gonna be the next clip here and get sound hopefully. Iggy Oggy Alaska is located on Lake Iliam the largest lake in Alaska. This is our port, this is our store and this is our post office. Our population's about 70 people we have quite a diversified local economy based on sport fishing, local company contracting, tribal government, the school and then private entrepreneurs. Then we have a community of people that are environmentally conscious and quite enthusiastic about the subsistence way of life. Got those computers and our telephones and our TVs and everything runs off the electricity where do you think that juice comes from? I don't know. Ask what? The generators? Some generators, right? I was just about to say that. Yeah, these are all diesel engines. We've had to fly in all our fuel which is really expensive. I think Anchorage is a year around 11 cents. Fairbanks is around 11 cents. Lower 48 is probably way less than 10 cents I'm sure. We're paying 52 cents a kilowatt hour for electricity. Energy is not something you think about too much coming from the lower 48, you know? But out here, you hear the hum of the generator all night long, you know? And you see the black plume of smoke coming up and you know that we pay, you know, high dollars. We get east wind and then we get northeast wind, northwest wind and south wind. Usually around 40, 35, 40. Once in a while, I got to 50, but I've seen at 80. So if you imagine a fish swimming like this, which each time it moves its tail over, it creates a vortex on the side. So if you have two fish swimming next to each other, it creates a vortex street that is turning like this in a water tunnel. They created obstacles that shut off vortices like that and they put a dead fish in the water and the dead fish moved upstream just by the energy that the body could extract from these vortices. And this was like the inspiration for taking these vertical axis wind turbines and also arranging them similar to fish in a fish school and see how that influences the power output of these turbines. So the main goal of providing all the electricity that the virtue of Igiyagic will have to amount to the region needs is broken down into three steps. The first one, bringing turbines out here and see if they can survive in the harsh conditions that they have up here in the winter. But after the second year, we should be able to judge exactly how much power can we get out of the turbines here. And then we can scale it up to the energy needs of Igiyagic. Like in the lower 48s, everybody wants clean energy but nobody wants big turbines in front of their houses. Which is partly also why we are doing this research on the small turbines because they blend in better into the environment. So I decided to put a battery bank in between the turbines and the grid. We were definitely high-fiving each other when we saw the numbers there. We were able to put the first significant amount of energy into their grid. The elementary school class stopped by while we were out there and they were checking out what we were doing. So we connected the computer to the math tower and showed them what wind patterns they had that was pretty cool. They were really excited about that. At some point, they might decide that they're interested in it and go down the road of maintaining that wind form but maybe also installing wind energy projects in the general area up there. Which I think will be really cool and exciting. I would hope that with projects like this, we can definitely extend the time that people are going to live out here and kind of live the way they want to live. So that gives you a sense of where we're going with some of this work and trying to transition this from academic concepts to something that can have real-world impact. And so more broadly in this area, we've been working with the Gordon and Betty Moore Foundation in thinking about distributed power for Alaskan villages. You heard in the segment, he mentioned them spending 50 to 55 cents per kilowatt hour, which is already a lot. But there's villages that are up almost to a dollar, a kilowatt hour, because of these costs of transporting fuel to these remote villages. And again, at the same time, they have in many cases, excellent wind resources that they can bring to bear. And again, we're excited about the opportunity for community engagement in these projects. We found, for example, in the school, the students really get excited about thinking about simple geometry problems when it relates to the wind and the direction that it's pointing. It allows that work to become much more real for the kids there. Just a couple of other areas just to let you know where we're going. And then I'll wrap up. We're working with the Department of Defense, which is the largest single agency consumer of energy, to think about issues of combat energy security. So if you do that same calculation of how much a gallon of fuel costs for the military, it becomes very high when you think about the cost of protecting the fuel convoy, for example. In the case of large wind turbines, they're really not feasible for forward operating bases. Even for permanent bases, it's a challenge because of helicopter operations. So we've been working with them to develop these low-profile arrays that could generate power without interfering with their primary missions. And one of the results that came out of this project with ONR and Spaywar in San Diego was confirming the very low radar cross-section of these arrays, which allows them to be used in that context. And then one last bit is locally here in California, as you know, if you've driven down the 580, we were one of the pioneers in wind energy worldwide. We also have some of the best wind resources. And yet, many of those locations are occupied by outdated turbines. Now, many of these companies are pursuing ambitious repowering initiatives, taking down the old turbines, putting up more efficient new ones, but that can come at significant expense. And so one of the ideas that we've had for a while and have been working with Jeff Koseff, for example, on is putting these vertical-axis turbines in the understory, underneath the existing turbines, without even taking them out. And so in some cases, that allows you then to generate additional power without having to go through laborious permitting processes. You have your interconnects that are sitting right there. And again, you're sitting on some of the best wind resources that are out there. So interestingly, there was just an article that came out literally two weeks ago. Some colleagues of ours, Christina Archers of Stanford alum, Niranha Gaysas is a postdoc here at Stanford now, and they did some computer modeling of this scenario, of these vertical-axis turbines sitting below the large horizontal-axis ones. And just to pick out one quote, the vertically staggered wind farm, so this is that combination, vertical-axis horizontal-axis farm, produces up to 32% more power than the traditional one. And interestingly, the power extracted by the large turbines alone is increased by 10%. So that interaction aerodynamically between the large turbines and the smaller ones actually improves the performance of the existing turbines. And again, 10% on these projects, that's a significant amount. Now again, this is through computer modeling, and we wanna pursue this further through more field testing, but it suggests that these vertical-axis turbines might be able to not only support new projects where you're generating energy from a green field project, as we would call it, but that in this repowering context, they could also have a significant impact. So let me finish there and just, I don't wanna leave without noting the wonderful students that were able to attract to this type of work. They're very excited about energy research. Many of you know this. Many of you are those excited students, and thank you for coming. But we've been working with a number of universities who now I think are seeing and getting excited about the idea of these vertical-axis turbines. It's true that if you go back 30 years, some of the veterans of the wind industry will say, well, we've been there and done that. The vertical-axis turbines were tried, and they weren't successful in the large-scale iteration, but people are now coming around to the fact that new advances in computation, new advances in materials, and simply a new way of integrating these turbines together allows for us to rethink vertical-axis turbines as an energy solution. And then lastly, many of our funding agencies, I mentioned the Gordon and Moore Foundation, MAP Royalty, Jane Woodward is a Stanford alum, is their CEO, and they've been very supportive of our new research initiatives, and then also NSF and the Office of Naval Research. So with that, I would be glad to take any of your questions and thank you for your time. This sounds really terrific. Do you have people clamoring to put in these things? That sounds fantastic. So I would say that there's certainly interest in the implementation of these turbines, but the challenge has been delivering a product that is bug-free, and what I mean by that is most of the companies that sell these are startups that are still trying to work through the kinks of building something that can last for 20 years. Now, one of the things that's been a benefit of our field research is that we've had two companies come to us and say, we have the perfect wind turbine for your paradigm here, and we've tested it in our wind tunnel, and we've done the computer modeling, and it works wonderfully, and we put it out at our field site, and two weeks later it's broken down. So getting designs that are able to withstand the real environment is a challenge, and the reality is in energy science that leap that you make from an interesting idea to something that works in the real world is always tough, but in wind energy in particular, you need these systems to operate in the real turbulent environment with weather, with precipitation, and so on, and that's where we started to prove this out. So there are a couple of companies that I think are close to having something that I would recommend to my parents to buy, or that's sort of the metric I would use. Do I trust them that well? But they're not quite there yet. So there's still work to be done on the individual turbines and the reliability that's required, especially when you're making so many of them. So have any of the major winds, you know, Vesta or GE, come to you and said, hey, they wanna, you know, or they'd view this as a threat, or do they view this as an opportunity? So I think they're both interested. So GE, for example, I mean, I showed you the advertisement that came there, and that's sort of not for nothing. We went to talk to them maybe three years ago, you know, we're still waiting for a royalty check from that, but that's another story. So they're aware of the idea. I think it's certainly the case that they're not going to change their entire paradigm and move to another platform. But this last result that I showed you here is the one that they're pretty keenly interested in. So right now they have to try to make a guess for how many turbines they're gonna site and how much power is going to be produced. And an area that's a big challenge in wind farms is underperformance, meaning you assume this wind farm is gonna produce 100 megawatts, but because of that turbulence that I described earlier, it produces 85 or something like that. And in the case of the large turbines, there's no easy fix. I can't put another big turbine there, but I could ramp up my power by sprinkling in these smaller turbines in between them. So that's a scenario in which they and Siemens have been in contact with us and are interested in potentially pursuing a demonstration. Thanks. The dated vertical axis technology, the Darius in particular, it required a motor to get started. Do you have the same requirement? Because of the length of the shape. We don't. So the difference here, the conventional wind turbines to which the gentleman's referring had two blades that sat in sort of, troposkeen is what we call it, but the shape of a jump rope basically when it's pulled out. And because of that, if it wasn't in the right position to the wind, it had to be started up. All of the modern systems have two advantages. One is that the inertia is just lower. They're much lighter, so it's easier to get them started. But also they tend to be either three or five bladed. And so that means that they tend to be located in such an orientation that they can always become started. So there's no power required as an input. I would also note just since it came to mind that a benefit of these turbines today is that they're much simpler than that design. So a conventional horizontal axis wind turbine has about 8,000 components in it, from the gearbox to the system to point it into the wind, to the transmission and so on. These turbines that we're describing here have, depending on how you count, 12 to 20 components. So they're very simple. They use a permanent magnet generator. There's no gearbox. There's no system pointing it into the wind. All of these things can potentially lead to a very low-cost, well-engineered product. It still needs to be proved for the long-term reliability that this happens because what ends up happening, and I'm an engineer, I do this too, you say, well, wouldn't it be cool if it could do this and that and the other thing? And so these systems that you find from commercial companies tend to be more complicated than they need to be. But these could be really simple, dumb systems that just work. The wind energy from horizontalers, now some of the cheapest energy out there. Have you actually projected the LCOE for the vertical, assuming that it all worked and was reliable? Yeah, so the uncertainties there are in, first of all, the lifetime of the system. And then secondly, in the operations and maintenance costs, because that's basically what you're gonna be paying for down the road. Both of those are on paper, and I emphasize on paper, lower than they are for the conventional system. But again, I don't have a system I can point to today and say that costs a dollar a watt to install or two cents or three cents a kilowatt hour. So on paper it should be less expensive and the models say it would be, but I wouldn't believe it until I saw it. So it would scale with the, until you get to large size. I was gonna show the plot of the power density. It directly connects to the power density. It's not linear with the power density, so getting a factor of six more power density is not going to give you a factor of six greater because there's other limits. But you could certainly get to 50% lower costs or lower costs of the energy. Again, on paper. The big challenge we have is that if you saw in that video, you had students who are putting together these things one at a time and when we put in an order for these, the factory that makes these blades is making them one at a time. So you're paying first unit costs for all of these things. In practice, if you had the full array that we're hoping to go to in a geogre will be something like 40 or 50 turbines. So if you can order 50 of them, it's much less expensive per unit. So the projections I'm talking about are at that scale. Sorry, there's one in the very back, and then I'll come back here. Would these principles be applicable to small scale hydro as well? Oh, that's a fantastic question. Yeah, and in fact, so in this village, I mentioned that there's a river running by it. So we're working with a group at the University of Washington who's studying a single tidal turbine right now. But you can basically imagine taking one of these turbines and sticking it underwater. And the same fluid mechanics principles apply. And so absolutely, we're looking at how we can array under water to take up less of the waterway space. In the water, it's actually a bigger issue because they have salmon runs, for example, and they wanna make sure that this is not going to interfere with those environmental impacts. But the computer models that we're developing to predict performance here are gonna be almost directly used to optimize the hydrokinetic system. Oh yes, in the front, and then here. I'm skeptical for one primary reason. So if you think about the actual aerodynamics, a horizontal-axis turbine blade is almost always seeing the same angle of attack as what we call it. So think of the angle that the wind is going to hit the blade. It doesn't change as a function of time. And so that allows for you to have a really smooth flow passing over the blade almost always, say for gusts and things like that. By contrast, in the case of these vertical-axis wind turbines, the blades, because they're rotating, they're changing their angle relative to the wind, twice per cycle, it turns out, as it goes around. And so because of that, you get inefficiencies that I think are difficult to get around. Now, there is one example from the 70s of what's called the cyclo turbine. That was a turbine where the blades themselves, as they rotated, almost like on a helicopter, would change their angle of attack once per revolution. And those were getting efficiencies close to horizontal-axis turbines, but the mechanical complexity is really high. And so that's not a system I would expect to be able to withstand a 20-year life cycle. Yeah, in the back. So looking forward to the outlook for using wind energy in the future, and especially on a large industrial scale, thinking back to your graph with the population density and how much power we use, do you think that these technologies are going to get us anywhere close to where the more industrialized countries are, and especially with our increasing energy consumption? Well, I think we're going to have to fight it from both sides. And we know we're seeing it in our Alaska case here, where we need energy efficiency along with new energy generation. The real challenge I see in generating energy in a place like Palo Alto, let's say, is that there isn't a good technology to tell you where to install the systems. So right now there's really interesting projects where I can go online and find out what's the solar capacity on the roof of my house. And I can then, on that basis, decide is it economical or not for me to install solar panels. There isn't, right now, an equivalent tool for wind energy. And in part, it's because of the different physics. So I would argue simpler calculation to figure out solar insulation at a fixed location in space. The wind resource depends on what direction the wind came from, what was the friction of the objects around it on the way there. It's a really interesting, I think, fluid mechanics problem. And if anyone wants to fund us to think about this, we'd be happy to. But it's a tough problem. It's a really hard problem. I would love the day when you could go online and do the same thing for wind as you can do for solar, because I think that, combined with a technology that is reliable, is going to be the missing link to then to tap a lot of that energy. Yeah. I have a great question. First one, maybe should have the solar and hydro together to maximize the efficiency. Right. So that's why we cannot moment search about this. Yeah, those are all excellent questions. So on the first one, with regard to weather, there was actually a symposium at Harvard last spring to look at exactly this question of, if we were to do, as I suggested in South Korea, and literally cover the entire land area with equally spaced wind turbines, how would that impact the local wind flows? What we find is that, at most, at the spacings that we're used to turbines being at, the effect is negligible, in part because of the fact that these turbines are still operating relative to the atmospheric boundary layer very close to the ground. So the atmospheric boundary layer is that area where the winds basically are conveyed, and that can be something like a kilometer in height. So structures that are order 10 meters in our case, or even 100 meters, in computer models anyways, the effect is quite limited. The inverse problem you can think about is, in many cases, there's been mass deforestation. And so you can think about that as changing the friction of the local surface. And you don't tend to see large-scale changes in weather patterns because of that. To your second point about the locations of where they're installed, that's, again, an excellent point. And one of the reasons why we're interested in having a site in Alaska on the one hand, and in Southern California on the other, because we have very different weather profiles in the two locations. And what that's taught us, for example, is we were very concerned about icing in the Alaska case there and how that would impact these systems. It turns out that the vertical axis orientation is actually ideal because precipitation tends to run down to the bottom of the blade naturally due to gravity. And so we don't get the same type of accumulation that you tend to get on the larger ones. Your third question was with regard to sort of hybridization. And again, that's somewhere that we were really interested. One of the draws of coming up here to Stanford is there are people who are thinking about this in other contexts already. How do we take renewables? And we're going to have to complex them with conventional base load type of technology, both at macro scale, so thinking about municipalities, but also for a village like Iggyagic. I mean, we're excited about the renewables here, but when the wind is out, they still need the lights for their school to go on. They still need to be able to function. In this case, we're using a combination. You can see there's some panels here. In summer, that works. In winter, they're in the dark 20 hours a day, so it doesn't really work as well. But then diesel is the other part that we're using. What we're able to do, at least, though, is to offset how much of that fuel consumption that they have by trying to get every last bit of energy from the wind and from the hydrokinetic sources. There was one in the back there. Last question. Oh, well, there you go. I'll be here afterwards if anyone wants to continue to chat. So on the theme that things look one way in theory and then another one you get on the field, you mentioned two fairly significant things. One, you thought that the environmental impact in terms of wildlife was zero. I think you might have said zero, but that's what I'm gonna ask about. And then that the public opinion aspect is that the sightliness of it is better. So is that a theory prediction or is that in reality that there is no wildlife impact and that people like it? I'm glad you asked that. It's very timely because in being recruited up here to Stanford, one of our initial visions was of having a field site similar to the one in Southern California here in the Altamont Pass. And so we've went through starting in summer of 2014, really, the process of permitting and everything was going fine until this question arose. And the data we have is that we've been running a field site in Southern California. We have about 25,000 hours of data now and no bird strikes or no bat strikes. We've been doing monitoring at our site. But the planning commission can say, yeah, but that Southern California, this is the Altamont Pass. And so we got into this conundrum where there were people on staff there who said, we won't let you operate here until you can prove that you're not going to injure birds here. But of course I can't prove it unless you let me operate in the Altamont Pass. So you end up in these impasses where you're left pleading, negotiating. I haven't certainly worked out how is the best way to navigate that issue. But it is a significant one, especially in places where there is this preconceived notion of the environmental impact. So the fact of the matter is the lower height, the swept area, these are all things that you can point to and say, okay, this shouldn't be a problem, but public opinion is not always based on fact. So, yeah, sorry. So, turbulence question. Yes. Mentioned out there that the correlation of the fluctuation, that is the vertical and the horizontal, that is a main source of energy that has been overlooked. If that's the case, what are the conditions to maximize that? Is it sort of upper level atmospheric jet stream flow? Or is it features on the ground level that enhance that, that gives you the power? That's a great point. And so the answer is that the friction of the structures on earth enhances that turbulent effect and turns out to be a positive. So if you think about wind energy as it's conventionally thought about, you usually want to site these turbines away from turbulence because the fluctuating loads that the blades are going to see is a problem for their lifetime. It turns out in the vertical axis turbine case, because the turbine itself generates enough of its own turbulence, it was an earlier question about efficiency and why it's lower efficiency. These turbines actually are less sensitive to that negative effect of turbulence. And so we really just get the net benefit of operating closer to the ground where the turbulence is higher. If you're up in the jet stream, certainly you have the benefit of a higher wind speed, but the turbulence is going to be lower. So if I had an array of airborne wind energy systems, for example, it's actually harder to design a farm in that context because I don't get enough turbulence to replenish the later one. So the model that makes sense for airborne is a single, very large, very efficient system, not an array of these generators because of that difference. The one last thing I'll point out is that in terms of daytime weather, so anytime at night, when the ground level is cool, we have what's called a stable atmosphere, so think of the air as being heavier, that tends to suppress the turbulence. And so anytime that you have heating on the ground, you can almost see that if you land at an airport in Las Vegas or something like that, there's often more turbulence. That time of day is also going to be more conducive to a turbulent effect there. Okay, thank you. Thanks very much. Thanks.