I bought a prototype airplane from Ampyx when they were dissolving this summer! I went to a random garage sale looking for cheap tools, it turned out to be the workshop of Ampyx power. I saw a nice RC airplane that they used for some early testing and I bought it for 30e. Its got a lot of repaired damage but turns out it was almost a 1000e when new :)
@@EngineeringwithRosie Can you perhaps tell us how much electric energy was generated after 23 hours of continuous work 10:00 ? Can you compare it with energy quantity generated by PV panel(s) >(how many of them?) for the same time period of 23 hours?
You remind me a bit of a Mechanical Engineering professor I had in college. Not just superficially (Caucasian woman), but the energy and apparent interest in actually teaching people. PS: She was an associate prof who came up for tenure when I was an undergrad. They denied her tenure because her research, while solid, wasn't particularly flashy or innovated (this was at Caltech). The students pressured the department to reconsider with the argument that teaching skill (which she was great at) needs to carry more weight than they were giving it... and she ended up getting tenure. I don't imagine that happening today, but maybe things will change again... teaching is still important.
Oh that's so nice that she got tenure! One of my family members won her old university's teaching award one year and had her contract discontinued the next. It's super common that teaching skills aren't valued at all.
You'd be surprised by how few variations there are on not just genetics but personality. I guarantee that somewhere out there is an exact carbon copy of me.
I'm a bit late to have my question answered on the live stream but I'll ask it anyway. Why not use a non tethered drone to launch a non powered sail. When ground wind is low the sail could be folded similar to a parachute loaded onto the bottom of a "launching drone" and flown up and deployed. This would reduce the window of risk and wear to the expensive components. You could even have one launch drone service multiple towers within a short range. The problem would seem to be in repeatability, but I can think of a few ways this could be done with automation while still having reduced cost over the built in drone launch systems.
I believe this to be a very good idea. Especially once you have multiple systems close to each other. This idea has been raised by at least 2 other people in the business that I know. As long as we have only one system for testing we decided to fix the propellers to the wing to avoid the complexity of having another autonomous system and the necessary communication/synchronization that comes with that. But maybe we should change that...
One problem with scaling them up is volume/weight increases with cube of aircraft's size while lift only quadratically. About launching in low ground wind - autonomous drones used as lift robots might have a say.
That's a very important consideration. By using multiple line attachments along the wing spar you can get below cubic weight increase. Thought experiment: Glue the left wing tip of one kite to the right wing tip of the other. If both have their own tether you don't need additional structure.
Hi from the uk As an old git now I enjoyed flying kites with my kids when they were small it's great that the humble kite can be put to work. I would love to see this happen. Would sails and kites be a reasonable addition to heavy shipping passenger or goods as an offset to diesel power? It might be cool to see a modern version of the old square riggers sailing again
It's around for a while doesn't make it more feasible. The "Hyperloop" idea exists more than 200 years now, still not achievable. So they need an extrem amount of space, so they don't interfere with each other! How big do they need to be, to compete with a conventional wind turbine? Because of the nature of the setup you need lots more of safety and precautions measures. You put one of these, where you could have a whole windfarm of conventional wind turbines? And about birds, maybe less direct killings than conventional wind turbines. But what about the additional stress and probable behavior changes? They mimic a bird of pray in many respects, so how would that influence the birds around, always a shadow lurking in the skies. Especially if you are at places with ground hatching colonies. And the bird killing argument is anyway mostly a straw man. If that's a concern to anyone, then get rid of the house cats first, which kill way way more! Or humans that hunt and kill tons of migrating songbirds, especially in Southern Europe, with the cruelest of methods! So in the end, this ideas sound neat and may have some niche, but on large scale way too complicated and introducing so many additional moving parts, that all are points of failure.
Hi Rosie, nice video! Looking forward to the interview with Roland Schmehl. Just one comment on the point that a soft kite is difficult to launch if there is no wind at ground level but higher up: I think this is a little bit theoretical because especially in the first years you would choose sites where this wouldn't happen - usually there needs to be open space of 800-1000m radius around the ground station. In these locations, you would have sufficient wind also on the ground level (3-4 m/s) if there is good wind further up. Anyways, as you also pointed out, the challenge is right now to get as many operational hours as possible to gain experience and improve reliability; that is why we are looking for test and demonstration site where companies can fly 24/7.
Was really hoping skysails or similar solution to work out, but eventually came to my own conclusion that it will likely always be niche. Partly because it's really hard to build a wind-park with them (tangled lines) and safety issues (lines breaking) means it's not really fit for wide area adoption either. I think as a power-source for ships it's probably a cool idea, but much harder even for sparsely populated areas. Maybe it will be easier to deploy in the ocean since the anchoring is a lot simpler than regular off-shore wind.
I just spoke with the SkySails co-founder last night and got some interesting insights from him. Their initial market is replacing diesel generators in off grid applications like islands. Then eventually multi megawatt floating offshore, but there's a loooong development path until that point! He also said the ships application was a dead end for them because they're not willing to pay anything extra to reduce emissions. But that was a few years ago, maybe it'll change.
I'm keeping fingers crossed for the paraglider type devices. Because there is no cheaper aircraft than this and the problems you listed are resolvable with intelligence (software) which once created (written and tested), can be reused on mass scale at pretty much zero cost. Software can make them talk to each other to avoid collisions. Paraglider wing can change its shape, enabling it to react to changing wind conditions. For example, in a gust of wind, the wing can quickly contract (making itself smaller and thus more stable), and get evacuated downwards by the ground generator device pulling on the anchor line. Once you have the functional software, then you don't need rocket science or rare materials, you only need easily accessible textiles and a tailor to make the wings :) (Obviously, readily available power generator is placed on ground, and finding suitable actuators to control the wing in the air should not be a problem) To me, it is more a software challenge and ultimately a feasible one, with enormous potential :)
Back around 1980 I had Bryan Roberts as a lecturer at USyd. He was looking at units which would fly in the jet stream. One of the problems was finding a suitable material for a tether that would not break under its own weight. I saw in a later article that he was looking at a group of 10MW units.
Most if not all, currently pursued concepts are aiming at heights between 150 and 500 meters, maybe a bit higher. At these heights, there is no danger that the tether breaks under its weight. Challenges are (1) aerodynamic load peaks when flying crosswind in a fluctuating wind field and (2) fatigue of the tether due to dynamic loading, especially when alternatingly reeling out and in and (3) material degradation due to UV. The pioneers of our trade (Oberth, Roberts, Ockels, ...) envisioned much higher altitudes. That is currently not the case anymore.
That was an interesting video. Thank you. My take, being a retired pilot is that apart from low volume, very specific applications this is a non-starter. There is no doubt that the wind gradient is an exploitable resource. Utilising upper air is as you say, far better because it moves faster. It’s also more stable (fewer gusts) and slightly more reliable than surface wind. The better, more elegant solution has to be airborne generation as the wind will provide the lift for free as the craft is tethered making weight less of an issue. Being a kite flyer I know controlling these things is non-trivial but think this can be overcome. However, it’s the total system complexity that will prevent cheap power from being generated. Then bird murder, icing, aesthetics, noise and rain damage has to be considered along with establishing safe zones to avoid conflicts with aircraft and people on the ground when they crash. A minor point windsheer, the difference in windspeed between layers of air, is a minor aspect of a larger phenomena called the wind gradient. It is as you say caused by surface friction.
Reminds me of ocean wave energy. Lightweight moving parts transferring the power to be harvested is really hard to make reliable over economically viable time frames.
I don't ever see this working for commercial power anytime soon. I mean it would be awesome if you could get it to work for your home, but do we really want that? For camping, disaster, or the military? That is what I would be going for. Imagine having a small generator you could carry in a backpack for instance. PS: Can just use hydrogen to launch the soft ones when no wind is available. I also remember someone talking about a design for a hybrid airship one that also had a turbine on it. It was tethered and moved up or down.
Has anyone done a flygen (ground gen?) system with a pure rotorcraft (no wing)? I'm thinking a heavy-lift helicopter sized autogyro. I wonder if that would offer more control and weather resistance compared to a flexible or rigid wing.
I can certainly see the emergency use case being viable. I would love to see a commercially viable product for everyday use, but it seems to be in the same category as wave generation. Always just a bit out of reach. Thank you so much for these videos. It's delightful to have new ideas to contemplate.
That's a good comparison. I also have a soft spot for wave energy! But I think airborne wind's challenges will be much easier to solve than wave energy's.
Until his death in 2014 Dutch astronaut Wubbo Ockels was involved in the research that led to the company Kitepower. In one interview he talked about the applications of these systems. Saying there are many instances where places need additional power and currently in those cases diesel generators are used. As a example have gave large multi day music festivals
Wave energy has been tested and deployed. Floating Power Plant is deploying near Gran Canary. The wave power is basically a free add to a floating platform that stabilize the floating fundament and allow easy maintenance ship access.
There is about a 0.0000017 chance of seeing electricity producing kites anytime in the foreseeable future. If it is even possible to keep all 7.888 billion people alive without fossil fuels, it would require a massive drop in the standard of living. Anyone who thinks we can keep this thing we call civilization going without a hiccup or major changes to our lives is in for a rude awakening.
Would it be viable to have a kite system that could fit in the trunk of an electric vehicle then driving the vehicle multiple days cross-country only charging from a kite system? Also, how are lightning strikes factored in? It's a bit of a Benjamin Franklin thing to hang a very conductive wire kite.
That's exactly what we're trying to do :) It's possible to make it fit inside the vehicle and still be powerful enough to charge it in one night. For example Kitemill have a >10kW 6 meter wingspan prototype that can be taken apart. Regarding the lightning, we will use a script that checks the weather forecast regularly and orders the kite to autonomously land in case of unsuitable weather. Check out our videos to see such a landing :)
That's exactly how it's done. Or at least how we are doing it. The groundstation keeps the tension of the tether constant. If you like, checkout the code. It's open source on hackaday.
Would this be a good option in the case of cargo shipping to recharge batteries that power electric propulsion? It seems similar to the sail-based wind options and since in deep water there would be few restrictions, I would think it could be useful.
The reason Skysail stopped trying to power cargo ships was that the economic incentives were misaligned. There are very few owner/operators. Most of the time the people who own the ships don't buy the fuel. That is paid for as part of the cargo shipping costs. So the people who make the savings from the sails don't own the boat and can't install the sail, and the people who do own the boat don't make any savings because they don't buy the fuel. It could certainly work with the owner/operators out there, but you have to figure out those misaligned incentives first before you can appeal to the majority of cargo ships.
The previous incarnation of my company was trying to do exactly that, but it turned out to make more sense to use the kite for direct propulsion, rather than going through the electrical conversion process. There can be an advantage in wider utilisation of different wind directions (you get electricity from any direction, but only useful propulsion from a few), but then you have to account for the effects of the kite's line forces on the ship's heel & leeway (roll & side-slip).
Interesting. I remember watching the documentary on Makani. I don’t think I would say that jet engines are more complex than piston engines, incidentally. It is my understanding (based on a documentary about Frank Whittle) that what held them back initially was the heat-resistant materials required.
I drew one of these up about 50 years ago now in the basement. What it was was 5 blimps that were connected by bars in a pentagram cross, and rigidly supporting a nacelle directly from the cross - that nacelle would be steerable into wind angle and generation power that transferred down a cable to the ground. Never did the physics/costing as I was 12 at the time- which was the summer we walked on the moon. only paid attention to solar and nuclear after that for about 35 years and then wind happened in TX. Enjoy your videos.
The problem with blimps is that there is a serious global helium shortage that's unlikely to change unless fusion power becomes practical and the use of hydrogen even for unmanned applications are still frowned upon (yes, the bias against hydrogen is a little irrational with unmanned applications but people and specifically bureaucracy are rarely rational). However, there may be alternatives such as solar heated hot air or nitrogen as nitrogen is still a minimal lifting gas versus air and can be easily produced where ever air is available.
You said something right. Jet engines are so complicated, but that doesn't mean... well there is a market for those. Anyway, for me it seems for this technology there is a very narrow market...
"Just the economics" not working out is the problem with most of the "promising" technologies we hear about in excited optimistic voices every day. The other common problem of course is the engineering not working out. "Good" ideas are easy, engineering and cost control are hard. Manufacturing at scale is even harder.
Gusts can be handled by reducing lift further than gain in drag. For flexible kit roll up the wing. This would require power be sent to the kit v. Cable length or electrical power. Launch by hydrogen and closed cells.
As someone who spends most of my working time espousing the benefits and challenges of renewables, I really love hearing the engineering perspective when it comes to renewable technologies. Great video!
How do you have anything with worthwhile power output that doesn't need some sort of ground infrastructure to stop it wandering off or get the power to the groun? . Any decent sized wing in a decent wind will pull a container around,, look at bouncy castles taking off accidentally. The wing will be using a lot of its energy in flying. If you extract too much energy from the wind it will slow down and stall the wing. If people are not happy about traditional wind turbines next door, they won't be happy with these wandering around next door.
How is a free flight drone with windmills on it supposed to work? The wing needs to be going forward to maintain lift and will be driven forward by its motors and propellers. The windmills will increase drag more as they try to extract more energy from the incoming airflow, (that's why planes feather the prop on a failed propellor engine because of the extra drag slowing it down dangerously). So unless you are using more energy to move the wing forwards to keep it in the air than you are extracting, you will stall the wing. The same would happen with a tethered wing eventually, although at least you are not having to use energy to lift the wing in the first place. At least with a tethered wing you could use the tether to transport the generated power. How is a free flight one supposed to do it, heavy batteries that require even more energy to get them into the air? I can see why the ship parachute hasn't got traction, it only really helps when the wind is directly behind the direction of travel. It is not controllable like a sail so can't really be used off wind. Even if the wind is a few degrees from the direction of travel, you would effectively be tacking across the wind and possibly using more fuel to keep on course than if you didn't use the kite. So with all of the aggravation in deploying, maintaining, it etc not worth the purchase price or cluttering up useful bits of the ship.
4:49 Regarding birds, should be noted that at least one experiment suggests painting a single turbine blade a contrasting shade or color can reduces bird deaths by 70% (Smøla Wind Farm in Norway). If other experiments confirm those results, then there's no reason why increased visual contrast can't be used by airborne power generation tech, too.
Regarding birds, how many birds do skyscrapers kill as they are blinded and confused by reflections in morning and afternoon? This must be part of the equation as well. It is sad but needs to be considered.
@@donovanfoto3263 While an important point, that's a different conversation for a different set of engineers to deal with. Gotta make sure you pick the right battle at the right time with the right people, you know?
David G: I understand, my point is "Both kill birds, so which kills the least amount of bird?" I know people that are against windmills because they kill birds, however they don't seem to mind skyscrapers. Just pointing out BOTH KILL BIRDS. Then let them decide which is worse. After that, we can look into the environmental impact of coal and oil and make a larger comparison. I know some people that can't see anything but "Windmills are bad PERIOD, long live oil and coal."
you missed an alternative for dealing with gusts -- furling. Early tower-mounted wind turbines often had a spring-loaded offset tail, something in the same realm could be done with airborne systems.
This reminds me of the tidal planes/kites made by Minesto. It’s like large drones that are tethered to the bottom of the ocean and fly in figure 8 motion to increase the speed of the turbine, so they produce more power during tides, and can produce power during both high and low tide. Would you be able to talk about those some time? ☺️ I’m very interested in how it all works. They are currently testing it in the Faroe Islands and the small kites are supplying some power to the national grid. They are currently testing much larger ones as well there as well.
Glad to see KitePower are still doing well. I spent about 5 years in the run-up to my retirement as a consultant to them. It was interesting work and a delight to work with so many talented young engineers and was a good way to circle my career that started in atmospheric physics but strayed a lot in the middle!
i see the most potential in offshore applications where you cant just build a big wind turbine on a tower... for example on science expeditions when you stay for a couple days on one location or something like container ships getting additional power from the wind...
Great and balanced exposition. I agree with your analysis. Still at sufficient scale and high enough in the air it might be a great solution with less visual and noise pollution than ground-based systems. It's also an inspiring engineering challenge. Launch and land may be done with active motors, gusts may be (partially) treated by changing the pitch angles / lifting surfaces. Weather prediction is still progressing with cheaper, better and more widespread radar systems. Even if recently some investers have been pulling out (due to recent interest rate increases) in the long term there appears to be potential. I'm most worried about lifespan and energy performance versus maintenance, construction and material cost.
You are correct! The cost and footprint could be so light, you could have pop-up wind farms! Also bring wind to places that are not normally considered. You could even equip overland vehicles with small child kite sized ones... Hey, what about a kite tree, a central hub with kites constantly rotating around? I love the idea of smart kites communicating with each other to coordinate.
I certainly see a way to make this hip at sea, with energy contests. On land however, I believe we are limited between 3 and 15 meters per second to make it work. Windgusts and direction changes are not advised.
Maybe having intentional breaking points in the many lines between kites and the main cable could allow the kites to collapse in case of overload so it just sinks to the ground where it can be replaced.
Gilders do use a weak link...but there in lies the problem. The sudden release of load in a cable under significant tension will almost certainly throw loops onto the drum of the winch or cause knots to form in an automated recovery. Usually for a cable break the end has to be recovered under tension manually to pay the tether onto the drum correctly or you'll just create future problems.
I think you miss one of the advantages of airborne wind. You don't have to build them to survive hurricanes. If a gale is on the way you just pull down your kite/blimp/gyro/whatever as the wind builds up, just like a sailor reefing the mansail. This means they can get away with much lighter construction (including the tether) than a fixed turbine. Whether tthis is enough to overcome the downsides of the approach, though, is another question.
So, in sailing you can tack against the wind. If you've got a sail up in the air, you can let it run out the reel to get power. Could you design a sail that could adjust its shape to tack back in? Are there any systems that maybe use two anchors, so they can take keep tension on one tether while 'resetting' tension on the other? I remember flying kites as a kid how quickly they could move side to side. Even if a kite could lose some of its surface area so it could 'fall' a bit it could mean you could pull the tether in more quickly while it wasn't under tension. Maybe something like the parachute vent at the top of a hot air balloon. It would mean putting some technology up on the kite, but still be less than for full air gen.
Jet engines started out simpler then the engines they were replacing. Multi rows of piston cylinders arranged as corn kernels on a cobs or or some arrangement of v ,w or x, being pressurised by two super or turbo chargers replaced with a single chamber , with continuous combustion, with a single rotating part on a single axis was a simplification . The fact that the jet made more power was probably almost a bonus.
I wonder if combining functions is the secret to getting the economics to work? If you had a blimp with wind generators on it as well as functioning as a super tall cell tower for a large area it might be useful. The challenge would be getting the power down efficiently the long tether.
Excellent idea, can add solar and advertising billboards also I am thinking of being used in remote areS where conventional electricity is hard to get like the arctic or third world countries. Quick to set up. New technologies are always expensive at first.
@@user-fs9mv8px1y Its not a stupid idea, Advertising pays big money, About the same as having a billboard along the road and that seems to be ok? Otherwise i dont like the idea either. It erodes the environmental ambiance.
Interesting idea, I have given it some thought since your last video about it, I still think most of my initial reflections are relevant, for example I still think most projects focus too much on chasing energy efficiency over cost efficiency. I'm still skeptic about using crosswind, way more energy to harvest, all else equal sure, but also way more difficult to make it work, especially reliably, which should be pretty obvious to anyone by now. A non-crosswind unit that stays up can harvest infinitely more times the energy than what a crashed crosswind unit can. I suspect crosswind utilization represents the majority of what makes heavier than air systems more difficult than conventional wind power at same scale. A case that I don't think, but know they chased theoretical efficiency in vain is that balloon funnel. Lighter than air wind power systems should be shaped like airships, to have some chance of working practically. Just increase the rotor size to get higher output, that's not difficult. It's much easier to have variable pitch than make a balloon funnel adapt to varying wind speeds. An airship can be made big and also have solar on it. If it's made tough enough to operate at very high wind speeds at high altitude, it could just be lowered if the wind increases too much at normal operating altitude.
Hi Rosie, I had a Teams meeting today with Skysails, Hanover, where I put forward my concept of a seabed anchored rotating ring of 500 x 400sq mtr tractor kites. They were able to confirm that their autonomous controllers could reliably control flight in all points of the compass and that such a concept would generate hundreds of not thousands of megawatts/hr...All I need now is investors with deep pockets!
I can see a small scale version being used on sail boats for electrical power. Sailboats already have masts, travel within certain angles to the wind and are often quite far from populated areas, hence most of the disadvantages would be addressed and the smaller size of the equipment would be an advantage plus the trend for sailboats are towards hybrid sail and electric auxiliary propulsion. The forces transferred through the teether should assist in the sailboat thrust whereas generating electric power through the propellers increases the drag on the sailboat. Cameras, lidar and radar could also be mounted on the airborne generator to help AI detect semi-submerged cargo containers and other navigation obstacles that are increasing every year (sonar are ineffective against obstacles close to the surface of the water).
Probably not though. A much simpler solution for sail boat is to just attach a generator to the propeller that they already have for motoring up to docks. There are already hybrid and electric drive systems for sail boats that do this.
@@joashparker8271 Well, we already have electric sailing yachts that can use their props as a regenerative brake to trickle charge their batteries while under sail but we also still have many more sailing yachts with wind turbines and solar panels so one solution doesn't obsolete others. Besides an electric sailing yacht are designed and built as such whereas something like the kite turbine is portable, compact, accesses wind at altitude which are stronger and does not brake the sailing yacht but may actually add to the thrust that the yacht receives from the wind.
Interesting, thanks! I wonder how they'll deal with air law especially if those kites go near or above 500 ft. It would also be interesting to compare long-term costs vs ground turbines (which I think is controversial for those), the production per occupied square feet, and the perceived nuisance. About the birds, I thought they were fast enough to avoid most of propeller-based engines, I had no idea it was significant. But then, many are also killed by power lines...
Not a problem above 500ft. There are restricted flight ops areas all over the world, including over all military bases, most if not all Nuclear power sites, parachuting areas, every NFL football game, the White house and on and on. They get published on airspace maps and if they are temporary they go out with the local area notams.
@@johnway9853 I know that, but that's generally not abused and as you said, it's mostly temporary events. I've never seen many of those restricted areas when flying so it's rarely a bother (mostly some pesky drone areas), but if we need to deploy as much AWE as necessary to replace conventional wind turbines though, that will complicate the airspace significantly. Maybe it's easier in the US, but smaller countries have more complex airspace structures too, where it's common to have close CTR that don't leave much room in-between. Having such restrictions would effectively cut a lot of routes to GA traffic where they are most needed.
@@phenanrithe Every tower I controlled in, all 7 of them, had some sort of permanent restricted airspace nearby. The tower I retired from had a military base directly abutting us so the downwind for 09 had to be kept tight so as to not cross the line. Not like these things are going above FL180. I can see the point in some of the tight EU airspace but even then... as my first on the job ATC instructor used to love to say, It's a big sky. ;-)
@@phenanrithe LOL, I know what you mean. In 82 I got my PPL before going to ATC school. The difference in perspective is gigantic. My last tower was also a training tower with more Katanas than should be allowed in any one place on the planet. I figured these kites aren't going above a couple of thousand feet or the weight of the cables becomes an insurmountable issue. Add a couple more thousand on top like built up area rules, and it still makes it less of an issue than many of the snow topped granite barricades out where I started my career. Many a fuselage still on the sides of those mountain passes.
So, I'm thinking: - helicopter - triple-redundant autonomy. First two controllers are copies of each other in terms of processor and software; third is separately engineered and can safely land. - becomes gyrocopter when in the wind up high.
I'd say you got it all right. I especially like your focus on the bottom line. Too many videos about promising new technology which say that the details should be easily worked out, and then you never hear from them again.
Back in 2012, I designed a kite that would have the generator and prop framed in its center. It was supposed to be tethered to a station below, using an Adruino and anemometer to allow the kite to catch the wind in any direction (making corrections as needed). It was of course, all drawn on printer paper at home, and I had no idea how I'd make it or afford to try to make it back then. Now, I am hesitant to re-visit it, in fear of looking like a dumb dumb. lol Maybe I will build a scale model of it one day, and just take my pick up to a back road, in the mountains and try it out. lol
I just discovered your channel and really like it, thank you! I am a mechanical engineer myself and once unsuccessfully applied at enerkite, which also develop a airborn wind harvester, in 2016 or so. Since then I've been following there newsletters. Unfortunately, few things significantly seem to have improved, as they mainly ask for (crowd)funding. They plan to offer up to a 2MW units and do successful testing (since years, whatever that may mean...) and hire new technical personnel. So maybe they are worth checking them out once in a while.
Thanks Rosie for this interesting video. I’m a founder at Wind Fisher which is a newer entrant into this field. We resolve some of the issues you mentioned by using lighter-than-air, crosswind capable, Magnus effect balloons. I’d be happy to give you more details for inclusion in a future video. Kind regards, Garrett
Hi Garrett, I did see Wind Fisher and thought it was interesting. So many cool physics and engineering principles in one device! This video was intended to be on the more more commercially mature systems but I would be interested in Wind Fisher for a future video. Did you test a prototype yet?
It's a failed idea. It's too complex for power production. Ground based and ocean based wind turbines can and will get much bigger. Giant flying generators on a cable are impractical and the size is limited by physics. The safety margin required would require a huge cable for a megawatt sized flying turbine. The fastest growing and most successful green energy technology on the planet is ground/ocean based wind turbines. Just one of the new large turbines has made more power already than all the flying/kite wind turbines in history. Some ideas that sound good are just dumb. This is the solar roadways of wind. Countries, utilities and individuals build wind turbines because they pay for themselves within 3 to 5 years and make cheap green power for 20 to 25 years. They make money! Maintenance on electric wind generators is easy and equivalent to annually changing the oil and filter in your car.
Perfect explanation. Offshore deployment of windmills complying with much bigger power factor generation. That is what we are studying in Brasil as in other places too.
Your summation of the issues with kite power share a similar flaw that plagues not only this review of the tech but most of the energy tech media today. Rather than focusing on the merits and difficulties of the tech in question, everyone gets lost comparing apples and oranges, as if only a single company is going to supply one type of turbine to the world.
@@malachiteofmethuselah9713 my friend! I used to work as a project engineer in renewable generation for most 30 years. Despiste the merith, this kite technology is far beyound the energy challenge we are facing in world. And its not me that Will condemn an idea, the time and the payoff will do so!
Engineers see solutions in everything, but they often fail to grasp the downsides and potential problems with tech they develop, for example, lifetime cost vs upfront costs, metal tends to break apart when stress and load is put onto it, i see ONLY problems with a 24/7 flying structure that is suppose to last decades and reliably feed power to a grid that everyone depends on. A nuclear powerplant lasts for 50+ years, it's solid as hell and will probably never run into major issues during its expected lifetime, If i was an engineer i would focus my efforts into making nuclear powerplants better instead of this artificial tax-fueled wind power hype, if windpower could bear it's own weight in infrastructure costs, powergrid costs, no tax incentives or "green politics" what would be it's current price per kWh? and electricity can't really be stored cost-effectively, we should only measure price per kWh during windpowers minimum output days during a year and not peak production days) Start thinking stability and not fancy tax fueled green stuff please.
"Funiculating" two together sounds like you want them on connected tethers? Sounds like a nightmare for fouling and knotting. Rather you would have multiple units with distinct ground tethering points, far enough apart that the lines do not risk getting entangled. Since reeling in can be done much more quickly and under lower tension than the long crosswind flight which pulls the tether out, you would probably want more than two. I vaguely recall an early proposal that had multiple units moving at intervals along a loop railway track, probably using ground traction in place of constantly reeling out and back in. The advantage eludes my imagination though.
I don't need you to give me the right answer when you don't have it due to too much uncertainty. I'm blissfully happy with you explaining pros, and cons, and considerations. Just keep making them. I'll watch them all.
I was originally going to say that this concept is fairly stupid. After reading further into it for about 1/2hr or so I can see that there is potential there but the whole thing relying on winching in and out about 500m or so of a 1km long dyneema cable every 2 minutes 24/7 is a fairly obvious failure point.
For ground generation, why don't they use *two* kites pulling back and forth, slightly offset through aerodynamics so as not to get entangled? that way you wouldn't have to use power, just adjust aerodynamics mechanically to switch back and forth
That's mechanically more complex. If you consider the grid to be a power source, as well as the place you stick your generated energy, then it's fine to use a bit of grid power to pull the kite down and to thereby benefit from the mechanical simplicity of managing a single-kite generator. You can consider the periodic wind-in energy to have come from one of your other nearby generators which, in the big scheme, all averages out into acceptably smooth and reliable generation for the grid.
@@Rich-on6fe thanks. Yup, sure. Intermittency is no issue any more, we know how to deal with it. It just *sounds* like an inefficient way to do it, but at the end the numbers need to check out. Not always intuitive
Wish theyd try to make these smaller instead of bigger. Be pretty cool to hook a kite to a catch on a generator for emergency or remote power gen where solar isnt viable.
Is there any research being done on using a Lighter Than Air (LTA) device as a means to assist launching, the airborne part? And/or synergistically using existing or new tall structures, such as cellular or radio towers or even buildings?
@@EngineeringwithRosie as an addendum.. If you could. please ask about the possibility of deflating the LTA, such as via hose? to make retrieval easier and more controlled... Since I don't believe I'll be able to be online during the livestream... Good luck with Livestream....
Have you investigated much into kite-line drag? It is my understanding that it was underestimated, and turned out to be one of, if not the biggest impediment towards competitive efficiency. I'd be curious to know what the industry is doing. Once solution could be to create some kind of kite-line sheath that had a winglike cross section... in theory....
As you say it all comes down to the cost of the electricity produced. I would think they could operate the generator platform as a conventionally powered drone so it could take off and land and maybe power up if it had to for weather conditions but operate as a glider at other times but this would add to costs. It is a pity because it looks cool.
Why not instead of reeling it all the way back in, just have a dual-kite setup where as one extends it pulls the other in by being physically connected to the spool in the opposite direction. This way one when reaches its limit of length, it folds its wings in to a gliding mode and the more pulled in kite unfurls its wings for maximum drag. This could allow both kites to remain up in the ideal airflow zones by limiting the phasing distance too. Energy would then be mostly consistent as well.
Jets are not a good comparison because they are a military first technology where achieving greater capabilities is much more important than economic viability.
At 05:33 you state that in this study, “the local bird population was only active at night”. This literally cannot be true. Nearly all bird species are only active during the day because nearly all bird species cannot see at night. Owls are a very rare exception to this rule, but there is no place on the planet where the majority or all the birds are only active at night. This runs completely counter to everything we know about bird physiology.
Emergency power generation does at least seem to be one viable market since it has the advantage of not needing fuel over regular generators. Of course there's still solar it'd need to compete with, which might be hard given how dead simple and reliable solar is, it'd need to produce significantly more power for its cost and area used.
Thanks Rosie for the presentation and comments below. I think a smaller version for a home trial would be nice as a test unit although I don't have the wind in my site to test but it would be cool to see a sail in the air. Keep up the good work!
Good to see that such a technological diversity exists ! Who cares about bankrupt ?! Those technologies will survive because they're efficient enough to do so.
Makini style: I made something similar as a kid, but with more dihedral and sweep back. That gave me stability WITHOUT the need for computer controlled control surfaces. As for yaw stability: dragging a (bigger) propeller behind the tail, (or the main wings to a lesser degree IMHO) gives WAY more stability than having the prop try to 'push' yaw and pitch into the plane all the time. With this design it's almost as if the university/students wanted instability so they could say: "Look at our clever computer control system!" I had my model flying stably on the end of a fishing rod/line for sucks fakes! The only adjustment required was where the tow hitch is relative to the wing's center of lift: Want too land: move it to the nose. Want to take of: move it slowly from in front of CoL to slightly behind CoL. "A solution looking for a problem" is what I see here. If anyone finds this interesting: I would love to be involved in a KISS version of this idea.
A couple decades ago I floated this idea to an aerospace friend. He had a fit about airspace control, blah blah blah. It's that group that will protest the most about stuff invading "their" airspace, as if it belongs to them and them alone.
Hi Rosie, Great coverage of AWE. Please look into many-connected Kite Network topologies as the ultimate AWE scaling principle at highest density and safety, and also note that modern architectural and airplane fabrics are now certified for decade-plus service-life.
Great questions for the livestream. The really durable fabrics aren't used for kites yet because as I understand it they are much more expensive and it's cheaper overall to replace a cheaper fabric every 6-12 months. For now anyway, hopefully that'll change.
I remember watching a documentary about a team building one of these things and it was fascinating. The team was so bright and hard working but their financing ran out right when they found success and so they had to mothball it. I do think that the complicated control systems probably mean that it won't be a big player in the market, but, where they make sense, they'll be hard to beat once someone makes a truly viable product.
@@Deaner3D There's a doc about it, “Pulling Power from the Sky - The story of Makani”. Using the sky is probably not the best option. Imagine the same thing, but under the water. There's a number of different tech being explored, but something like the Makani in the deep sea flying a figure 8 could be interesting.
would it be possible to use a large airship to meaningfully, without great expense, reduce the draft of a oceangoing vessel that is laden with cargo and thusly reduce fuel costs?
Ultra High Flying Tetrahedral Kite!!! Create a Incredibly Massive Tetrahedral Kite that has thousand's of tetrahedral's, and place thousands of incredibly small wind generators in each of the individual tetrahedral's themselves within the kite itself, and route all the incredible small micro wires to a main location, where they all feed their electricity simultaneously together, and build the voltage up, and then direct it down the kite cable, and to the generator on the ocean ship!!! I Hope This Helps!!! And as far as I know none of this is copyrighted. Here is a video on Alexander Graham Bell's Tetrahedral Kites from 1903-1909 more than 100 years ago!!! For Study Material!!! Clean Energy For All!!! ruclips.net/video/BhwgOv8Mfyc/видео.html
Logistics (crossing tethers/tangling) would make scaling to large enough facilities to be economically viable "difficult"? Fixed wing would be vulnerable to "icing" phenomena the further away from the equator they're sited? Torsional power conveyance to the ground is fraught with "challenges"? I like the added energy available, and "noise" reduction, and relative reduced optical "footprint"/viewscape littering (until they crash), but many challenges lie ahead IMO..
Germany already wasted 430 Bln Euro on wind parks on the Dogger Bank before realizing that low availability is the major problem with wind that can not be overcome. On 430 Bln Euro Germany could easily built 90-120 nuclear reactors to cover 200 % of energy demand of whole country. Who pays for all this "wind" stuff?
Hey Rosie, what about stratospheric units that when failure occurs, they set off an ejection seat rocket while dropping the tether. The unit could go orbital till reaching an uninhabited drop point. Auto rotor programs could land it. OR.... let'er burn. LOL You know they will be all up and down the "Space Elevator" Do you think we will give these things highway names and numbers????
All I heard was......., fringe tech not likely to go above critical mass, because it hasn't, might be good Engineering, but insufficient demand from those with adequate funding. Keep trying. But "go fly a kite" will always be fun..
Shame that the Makani went out of business, I was really rooting for them. These kites would be PERFECT for remote locations like islands or small settlements as their size and footprints are small(er). No need to upscale them, they could really corner the market at the 100-200kW segment perfectly.
I designed something similar about thirty years ago. There's nothing technologically wrong with the idea; it has some obvious advantages over conventional turbines. It's a bit complex, but I think combined with a robotic controller it could be quite successful.
Why not set up panels of LITTLE pinwheels, on the sides of large buildings that often have strong winds hitting them, BUT instead of empowering electric generators, each pinwheel has a little air pump, that propels air through one-way valves into a network of tubes or pipes, collectively expelled into a SINGLE large scale turbine that turns an electric generator?
Keep exploring at brilliant.org/EngineeringwithRosie/. Get started for free, and hurry-the first 200 people get 20% off an annual premium subscription.
I'd like to see a comparison between the impact of (domesticated) cats and renewable energy on birds. "Some information suggests domestic cats pounce on from one billion to four billion birds a year in the lower 48, six billion to 22 billion small mammals, and hundreds of millions of reptiles and amphibians." So this kind of arguments should be put into perspective. This means that renewable wind energy kills "only 0.1%" of birds compared to cats.
I really hope "optimists" of all shades, understand the Impossibility of both windmills and kite windmills. The chance of these kites surviving more than a few weeks is minimal. The land area under threat of falling objects is vast. The whole idea is "utter fantasy", and Childs play. Very expensive Childs Play
Elon, King of creating fancy stuff for making the future interesting, should continue Makani. They have a huge documentation on youtube which was REALLY fun to watch. So maybe he can continue their story and he might eventually end up with something that works. Rocket powered kite ascent on no ground wind anyone? ^^
The solution of a blimp/dirigible seams like a natural answer to most of the design-dilemmas: Still mostly soft-body, but more rigid than kites. WAY simpler take-off, landing, and maneuvering than airfoil based flight... especially if it were ground-based generation as the balloon would basically need to be a buoyant sphere... same cross-section regardless of orientation of the balloon to the wind. Similarly, low wind at ground level is no barrier to lift, as the lifting capacity of the aerostat is independent of wind-speed. Yet your video indicated that only company that had tried a lighter-than-air solution had gone under... why?
There are certainly big issues with this. To get economies of scale you need big power outputs per machine, in the MW at least. Having a flying machine that operates autonomously but is big and heavy enough for multi-MW generation seems unlikely. AWE needs a lot of space (or ever more complex systems to avoid collisions) so the MW per sq km is likely to be limited. For me the big problem is that we are trying to replicate the huge controllable energy outputs that have been possible using fossil fuels, big hydro, and nuclear, replacing them with intermittent location-specific sources difficult to scale up.
Ok... It even could use much less materials but, the tridimensional SPACE required to operate this is absurd... I really doubt that the farmers and people that already complain about wind farms (visual pollution, sound and stuff) will be happy with this. How about a kite that have its cable snapped, what they do with that? ANd those techs does not seems simple or cheap at all.
I think the bulk of wind energy in the far future will be ionic wind generation. If they can get it to 20% efficiency, then anything else will struggle to stay viable. I could see a kite using ionic generation instead of a rotor, but I could also see an existing ionic wind generator that can generate in any environment, even a hurricane. We could see something like planet exploration where a kite could be used. There are already designs on using ionic wind generation on existing rotor blades to increase efficiency past 50%. I'm not sure kites would survive the NIMBY factor, even in remote locations with few houses. You wouldn't believe the push back in America's second least populous state of Wyoming for wind turbines.
If you are ever unfortunate enough to break down on a motorway, you will find that while standing on the hard shoulder, you will be battered by a constant strong wind from the slipstream of passing vehicles, especially trucks. When I am out walking on a windless day and then walk along the motorway feeder road near where I live, I get blasted by a strong wind from the passing vehicles. Is the UK Government missing a trick, by not lining motorways and fast feeder roads with vertical axis wind turbines, which will generally be turning all day and night from passing vehicles, regardless of atmospheric wind conditions?
Hello, I see any attempt with a kite kind of fruitless. High level wind generators are only feasible with in-built buoyancy - i.e., a turbine generator on a tethered blimp. With a multistage turbine it is possible to extract a large amount of energy from the wind, and protecting the blimp in the meantime. A set of gyroscopes (reaction wheels) would keep the surfaces in the optimal position, and protect the whole generator from sudden wind gusts. Greetings, Anthony
I bought a prototype airplane from Ampyx when they were dissolving this summer! I went to a random garage sale looking for cheap tools, it turned out to be the workshop of Ampyx power. I saw a nice RC airplane that they used for some early testing and I bought it for 30e. Its got a lot of repaired damage but turns out it was almost a 1000e when new :)
That is so cool!
@@EngineeringwithRosie Can you perhaps tell us how much electric energy was generated after 23 hours of continuous work 10:00 ? Can you compare it with energy quantity generated by PV panel(s) >(how many of them?) for the same time period of 23 hours?
You remind me a bit of a Mechanical Engineering professor I had in college. Not just superficially (Caucasian woman), but the energy and apparent interest in actually teaching people.
PS: She was an associate prof who came up for tenure when I was an undergrad. They denied her tenure because her research, while solid, wasn't particularly flashy or innovated (this was at Caltech). The students pressured the department to reconsider with the argument that teaching skill (which she was great at) needs to carry more weight than they were giving it... and she ended up getting tenure. I don't imagine that happening today, but maybe things will change again... teaching is still important.
Oh that's so nice that she got tenure! One of my family members won her old university's teaching award one year and had her contract discontinued the next. It's super common that teaching skills aren't valued at all.
You'd be surprised by how few variations there are on not just genetics but personality. I guarantee that somewhere out there is an exact carbon copy of me.
I'm a bit late to have my question answered on the live stream but I'll ask it anyway. Why not use a non tethered drone to launch a non powered sail. When ground wind is low the sail could be folded similar to a parachute loaded onto the bottom of a "launching drone" and flown up and deployed. This would reduce the window of risk and wear to the expensive components. You could even have one launch drone service multiple towers within a short range. The problem would seem to be in repeatability, but I can think of a few ways this could be done with automation while still having reduced cost over the built in drone launch systems.
I believe this to be a very good idea. Especially once you have multiple systems close to each other. This idea has been raised by at least 2 other people in the business that I know.
As long as we have only one system for testing we decided to fix the propellers to the wing to avoid the complexity of having another autonomous system and the necessary communication/synchronization that comes with that. But maybe we should change that...
Rosie, little off topic. Have you seen dynamic soaring? Faster then wind speed gliders. I think you might have referred to the physics in this video.
One problem with scaling them up is volume/weight increases with cube of aircraft's size while lift only quadratically. About launching in low ground wind - autonomous drones used as lift robots might have a say.
That's a very important consideration.
By using multiple line attachments along the wing spar you can get below cubic weight increase.
Thought experiment: Glue the left wing tip of one kite to the right wing tip of the other. If both have their own tether you don't need additional structure.
Hi from the uk
As an old git now I enjoyed flying kites with my kids when they were small it's great that the humble kite can be put to work. I would love to see this happen.
Would sails and kites be a reasonable addition to heavy shipping passenger or goods as an offset to diesel power? It might be cool to see a modern version of the old square riggers sailing again
It's around for a while doesn't make it more feasible. The "Hyperloop" idea exists more than 200 years now, still not achievable.
So they need an extrem amount of space, so they don't interfere with each other! How big do they need to be, to compete with a conventional wind turbine? Because of the nature of the setup you need lots more of safety and precautions measures. You put one of these, where you could have a whole windfarm of conventional wind turbines?
And about birds, maybe less direct killings than conventional wind turbines. But what about the additional stress and probable behavior changes? They mimic a bird of pray in many respects, so how would that influence the birds around, always a shadow lurking in the skies. Especially if you are at places with ground hatching colonies.
And the bird killing argument is anyway mostly a straw man. If that's a concern to anyone, then get rid of the house cats first, which kill way way more! Or humans that hunt and kill tons of migrating songbirds, especially in Southern Europe, with the cruelest of methods!
So in the end, this ideas sound neat and may have some niche, but on large scale way too complicated and introducing so many additional moving parts, that all are points of failure.
Hi Rosie, nice video! Looking forward to the interview with Roland Schmehl. Just one comment on the point that a soft kite is difficult to launch if there is no wind at ground level but higher up: I think this is a little bit theoretical because especially in the first years you would choose sites where this wouldn't happen - usually there needs to be open space of 800-1000m radius around the ground station. In these locations, you would have sufficient wind also on the ground level (3-4 m/s) if there is good wind further up.
Anyways, as you also pointed out, the challenge is right now to get as many operational hours as possible to gain experience and improve reliability; that is why we are looking for test and demonstration site where companies can fly 24/7.
Was really hoping skysails or similar solution to work out, but eventually came to my own conclusion that it will likely always be niche. Partly because it's really hard to build a wind-park with them (tangled lines) and safety issues (lines breaking) means it's not really fit for wide area adoption either. I think as a power-source for ships it's probably a cool idea, but much harder even for sparsely populated areas. Maybe it will be easier to deploy in the ocean since the anchoring is a lot simpler than regular off-shore wind.
I just spoke with the SkySails co-founder last night and got some interesting insights from him. Their initial market is replacing diesel generators in off grid applications like islands. Then eventually multi megawatt floating offshore, but there's a loooong development path until that point! He also said the ships application was a dead end for them because they're not willing to pay anything extra to reduce emissions. But that was a few years ago, maybe it'll change.
I'm keeping fingers crossed for the paraglider type devices. Because there is no cheaper aircraft than this and the problems you listed are resolvable with intelligence (software) which once created (written and tested), can be reused on mass scale at pretty much zero cost.
Software can make them talk to each other to avoid collisions. Paraglider wing can change its shape, enabling it to react to changing wind conditions. For example, in a gust of wind, the wing can quickly contract (making itself smaller and thus more stable), and get evacuated downwards by the ground generator device pulling on the anchor line.
Once you have the functional software, then you don't need rocket science or rare materials, you only need easily accessible textiles and a tailor to make the wings :)
(Obviously, readily available power generator is placed on ground, and finding suitable actuators to control the wing in the air should not be a problem)
To me, it is more a software challenge and ultimately a feasible one, with enormous potential :)
Back around 1980 I had Bryan Roberts as a lecturer at USyd. He was looking at units which would fly in the jet stream. One of the problems was finding a suitable material for a tether that would not break under its own weight. I saw in a later article that he was looking at a group of 10MW units.
Most if not all, currently pursued concepts are aiming at heights between 150 and 500 meters, maybe a bit higher. At these heights, there is no danger that the tether breaks under its weight. Challenges are (1) aerodynamic load peaks when flying crosswind in a fluctuating wind field and (2) fatigue of the tether due to dynamic loading, especially when alternatingly reeling out and in and (3) material degradation due to UV.
The pioneers of our trade (Oberth, Roberts, Ockels, ...) envisioned much higher altitudes. That is currently not the case anymore.
That was an interesting video. Thank you. My take, being a retired pilot is that apart from low volume, very specific applications this is a non-starter. There is no doubt that the wind gradient is an exploitable resource. Utilising upper air is as you say, far better because it moves faster. It’s also more stable (fewer gusts) and slightly more reliable than surface wind. The better, more elegant solution has to be airborne generation as the wind will provide the lift for free as the craft is tethered making weight less of an issue. Being a kite flyer I know controlling these things is non-trivial but think this can be overcome. However, it’s the total system complexity that will prevent cheap power from being generated. Then bird murder, icing, aesthetics, noise and rain damage has to be considered along with establishing safe zones to avoid conflicts with aircraft and people on the ground when they crash.
A minor point windsheer, the difference in windspeed between layers of air, is a minor aspect of a larger phenomena called the wind gradient. It is as you say caused by surface friction.
Reminds me of ocean wave energy. Lightweight moving parts transferring the power to be harvested is really hard to make reliable over economically viable time frames.
Yes, and time will tell whether the commercial systems that are starting to be sold now will have exorbitant maintenance costs or not.
however, one positive for airborne wind compared to ocean wave is that the energy density is much much higher, something like 20x more
I don't ever see this working for commercial power anytime soon.
I mean it would be awesome if you could get it to work for your home, but do we really want that?
For camping, disaster, or the military? That is what I would be going for.
Imagine having a small generator you could carry in a backpack for instance.
PS: Can just use hydrogen to launch the soft ones when no wind is available.
I also remember someone talking about a design for a hybrid airship one that also had a turbine on it. It was tethered and moved up or down.
It may be a bit impractical, or at least uneconomical…but *DAMN do i love Makani ; it’s so delightfully Kerbal*
Thanks for highlithing Airborne Wind Rosie! We need more like this. Amount of resources invested in AWE is still very low compered to its advantages.
Has anyone done a flygen (ground gen?) system with a pure rotorcraft (no wing)? I'm thinking a heavy-lift helicopter sized autogyro. I wonder if that would offer more control and weather resistance compared to a flexible or rigid wing.
I can certainly see the emergency use case being viable. I would love to see a commercially viable product for everyday use, but it seems to be in the same category as wave generation. Always just a bit out of reach.
Thank you so much for these videos. It's delightful to have new ideas to contemplate.
That's a good comparison. I also have a soft spot for wave energy! But I think airborne wind's challenges will be much easier to solve than wave energy's.
in addition to emergency use i could see it being useful for power for small scale industrial equipment that might not need to be constantly operable
Until his death in 2014 Dutch astronaut Wubbo Ockels was involved in the research that led to the company Kitepower.
In one interview he talked about the applications of these systems.
Saying there are many instances where places need additional power and currently in those cases diesel generators are used.
As a example have gave large multi day music festivals
Wave energy has been tested and deployed. Floating Power Plant is deploying near Gran Canary. The wave power is basically a free add to a floating platform that stabilize the floating fundament and allow easy maintenance ship access.
There is about a 0.0000017 chance of seeing electricity producing kites anytime in the foreseeable future.
If it is even possible to keep all 7.888 billion people alive without fossil fuels, it would require a massive drop in the standard of living. Anyone who thinks we can keep this thing we call civilization going without a hiccup or major changes to our lives is in for a rude awakening.
Would it be viable to have a kite system that could fit in the trunk of an electric vehicle then driving the vehicle multiple days cross-country only charging from a kite system? Also, how are lightning strikes factored in? It's a bit of a Benjamin Franklin thing to hang a very conductive wire kite.
That's exactly what we're trying to do :) It's possible to make it fit inside the vehicle and still be powerful enough to charge it in one night.
For example Kitemill have a >10kW 6 meter wingspan prototype that can be taken apart.
Regarding the lightning, we will use a script that checks the weather forecast regularly and orders the kite to autonomously land in case of unsuitable weather.
Check out our videos to see such a landing :)
In case of a gust, can't you have the controller of the ground system very quickly give out some tether to limit mechanical stress?
That's exactly how it's done. Or at least how we are doing it.
The groundstation keeps the tension of the tether constant.
If you like, checkout the code. It's open source on hackaday.
Would this be a good option in the case of cargo shipping to recharge batteries that power electric propulsion? It seems similar to the sail-based wind options and since in deep water there would be few restrictions, I would think it could be useful.
The reason Skysail stopped trying to power cargo ships was that the economic incentives were misaligned. There are very few owner/operators. Most of the time the people who own the ships don't buy the fuel. That is paid for as part of the cargo shipping costs. So the people who make the savings from the sails don't own the boat and can't install the sail, and the people who do own the boat don't make any savings because they don't buy the fuel.
It could certainly work with the owner/operators out there, but you have to figure out those misaligned incentives first before you can appeal to the majority of cargo ships.
The previous incarnation of my company was trying to do exactly that, but it turned out to make more sense to use the kite for direct propulsion, rather than going through the electrical conversion process. There can be an advantage in wider utilisation of different wind directions (you get electricity from any direction, but only useful propulsion from a few), but then you have to account for the effects of the kite's line forces on the ship's heel & leeway (roll & side-slip).
Interesting. I remember watching the documentary on Makani.
I don’t think I would say that jet engines are more complex than piston engines, incidentally. It is my understanding (based on a documentary about Frank Whittle) that what held them back initially was the heat-resistant materials required.
I drew one of these up about 50 years ago now in the basement. What it was was 5 blimps that were connected by bars in a pentagram cross, and rigidly supporting a nacelle directly from the cross - that nacelle would be steerable into wind angle and generation power that transferred down a cable to the ground. Never did the physics/costing as I was 12 at the time- which was the summer we walked on the moon. only paid attention to solar and nuclear after that for about 35 years and then wind happened in TX. Enjoy your videos.
The problem with blimps is that there is a serious global helium shortage that's unlikely to change unless fusion power becomes practical and the use of hydrogen even for unmanned applications are still frowned upon (yes, the bias against hydrogen is a little irrational with unmanned applications but people and specifically bureaucracy are rarely rational). However, there may be alternatives such as solar heated hot air or nitrogen as nitrogen is still a minimal lifting gas versus air and can be easily produced where ever air is available.
You said something right. Jet engines are so complicated, but that doesn't mean... well there is a market for those. Anyway, for me it seems for this technology there is a very narrow market...
i think the problem with this technology is the lack of RGB lighting on the airborne devices. Adding this will definitely make it look better
"Just the economics" not working out is the problem with most of the "promising" technologies we hear about in excited optimistic voices every day. The other common problem of course is the engineering not working out. "Good" ideas are easy, engineering and cost control are hard. Manufacturing at scale is even harder.
Gusts can be handled by reducing lift further than gain in drag. For flexible kit roll up the wing. This would require power be sent to the kit v. Cable length or electrical power.
Launch by hydrogen and closed cells.
Excellent lightning rod.!!😂
As someone who spends most of my working time espousing the benefits and challenges of renewables, I really love hearing the engineering perspective when it comes to renewable technologies. Great video!
All the money wasted on hot fusion should be diverted to renewables. Even just covering the landscape with flywheel storage would be a better spent.
And her videos are always so interesting!! I'm always quick to click when I see one of her videos on renewable e tech pop up in my list.
How do you have anything with worthwhile power output that doesn't need some sort of ground infrastructure to stop it wandering off or get the power to the groun? . Any decent sized wing in a decent wind will pull a container around,, look at bouncy castles taking off accidentally. The wing will be using a lot of its energy in flying. If you extract too much energy from the wind it will slow down and stall the wing.
If people are not happy about traditional wind turbines next door, they won't be happy with these wandering around next door.
How is a free flight drone with windmills on it supposed to work? The wing needs to be going forward to maintain lift and will be driven forward by its motors and propellers. The windmills will increase drag more as they try to extract more energy from the incoming airflow, (that's why planes feather the prop on a failed propellor engine because of the extra drag slowing it down dangerously). So unless you are using more energy to move the wing forwards to keep it in the air than you are extracting, you will stall the wing. The same would happen with a tethered wing eventually, although at least you are not having to use energy to lift the wing in the first place.
At least with a tethered wing you could use the tether to transport the generated power. How is a free flight one supposed to do it, heavy batteries that require even more energy to get them into the air?
I can see why the ship parachute hasn't got traction, it only really helps when the wind is directly behind the direction of travel. It is not controllable like a sail so can't really be used off wind. Even if the wind is a few degrees from the direction of travel, you would effectively be tacking across the wind and possibly using more fuel to keep on course than if you didn't use the kite. So with all of the aggravation in deploying, maintaining, it etc not worth the purchase price or cluttering up useful bits of the ship.
4:49 Regarding birds, should be noted that at least one experiment suggests painting a single turbine blade a contrasting shade or color can reduces bird deaths by 70% (Smøla Wind Farm in Norway).
If other experiments confirm those results, then there's no reason why increased visual contrast can't be used by airborne power generation tech, too.
Regarding birds, how many birds do skyscrapers kill as they are blinded and confused by reflections in morning and afternoon? This must be part of the equation as well. It is sad but needs to be considered.
@@donovanfoto3263 While an important point, that's a different conversation for a different set of engineers to deal with.
Gotta make sure you pick the right battle at the right time with the right people, you know?
David G: I understand, my point is "Both kill birds, so which kills the least amount of bird?" I know people that are against windmills because they kill birds, however they don't seem to mind skyscrapers. Just pointing out BOTH KILL BIRDS. Then let them decide which is worse. After that, we can look into the environmental impact of coal and oil and make a larger comparison.
I know some people that can't see anything but "Windmills are bad PERIOD, long live oil and coal."
@@donovanfoto3263 skyscrapers aren't particularly useful buildings compared to wind turbines
you missed an alternative for dealing with gusts -- furling.
Early tower-mounted wind turbines often had a spring-loaded offset tail, something in the same realm could be done with airborne systems.
Hi. I'm an engineer. A simple solution is to airborne wind turbine, which is to attach turbine(s) to a tethered airship (blimp)! 😆
It sucks that Makani was scrapped. It's a really cool concept and would have loved to see it grow and improve!
This reminds me of the tidal planes/kites made by Minesto. It’s like large drones that are tethered to the bottom of the ocean and fly in figure 8 motion to increase the speed of the turbine, so they produce more power during tides, and can produce power during both high and low tide.
Would you be able to talk about those some time? ☺️ I’m very interested in how it all works.
They are currently testing it in the Faroe Islands and the small kites are supplying some power to the national grid. They are currently testing much larger ones as well there as well.
Glad to see KitePower are still doing well. I spent about 5 years in the run-up to my retirement as a consultant to them. It was interesting work and a delight to work with so many talented young engineers and was a good way to circle my career that started in atmospheric physics but strayed a lot in the middle!
i see the most potential in offshore applications where you cant just build a big wind turbine on a tower... for example on science expeditions when you stay for a couple days on one location or something like container ships getting additional power from the wind...
Failed project. Has zero future. ZERO!
Great and balanced exposition. I agree with your analysis. Still at sufficient scale and high enough in the air it might be a great solution with less visual and noise pollution than ground-based systems. It's also an inspiring engineering challenge. Launch and land may be done with active motors, gusts may be (partially) treated by changing the pitch angles / lifting surfaces. Weather prediction is still progressing with cheaper, better and more widespread radar systems. Even if recently some investers have been pulling out (due to recent interest rate increases) in the long term there appears to be potential. I'm most worried about lifespan and energy performance versus maintenance, construction and material cost.
A first year Engineering student should be able to shoot this down within 30 seconds.
You are correct! The cost and footprint could be so light, you could have pop-up wind farms! Also bring wind to places that are not normally considered. You could even equip overland vehicles with small child kite sized ones...
Hey, what about a kite tree, a central hub with kites constantly rotating around? I love the idea of smart kites communicating with each other to coordinate.
I certainly see a way to make this hip at sea, with energy contests. On land however, I believe we are limited between 3 and 15 meters per second to make it work. Windgusts and direction changes are not advised.
Why have I never seen this channel before!? :o
Subscribed!
Maybe having intentional breaking points in the many lines between kites and the main cable could allow the kites to collapse in case of overload so it just sinks to the ground where it can be replaced.
Gilders do use a weak link...but there in lies the problem. The sudden release of load in a cable under significant tension will almost certainly throw loops onto the drum of the winch or cause knots to form in an automated recovery. Usually for a cable break the end has to be recovered under tension manually to pay the tether onto the drum correctly or you'll just create future problems.
I think you miss one of the advantages of airborne wind. You don't have to build them to survive hurricanes. If a gale is on the way you just pull down your kite/blimp/gyro/whatever as the wind builds up, just like a sailor reefing the mansail. This means they can get away with much lighter construction (including the tether) than a fixed turbine. Whether tthis is enough to overcome the downsides of the approach, though, is another question.
Exactly!
Rosie, little off topic. Have you seen dynamic soaring? Faster then wind speed gliders. I think you might have referred to the physics in this video.
There is a university also looking at a similar concept of jet stream soaring. There will be no NIMBI and noise complaints there.
So, in sailing you can tack against the wind. If you've got a sail up in the air, you can let it run out the reel to get power. Could you design a sail that could adjust its shape to tack back in? Are there any systems that maybe use two anchors, so they can take keep tension on one tether while 'resetting' tension on the other? I remember flying kites as a kid how quickly they could move side to side.
Even if a kite could lose some of its surface area so it could 'fall' a bit it could mean you could pull the tether in more quickly while it wasn't under tension. Maybe something like the parachute vent at the top of a hot air balloon. It would mean putting some technology up on the kite, but still be less than for full air gen.
I think you can achieve most of this with very few controls, not more than you would need to steer in three dimensions.
Jet engines started out simpler then the engines they were replacing. Multi rows of piston cylinders arranged as corn kernels on a cobs or or some arrangement of v ,w or x, being pressurised by two super or turbo chargers replaced with a single chamber , with continuous combustion, with a single rotating part on a single axis was a simplification . The fact that the jet made more power was probably almost a bonus.
So true!
I wonder if combining functions is the secret to getting the economics to work? If you had a blimp with wind generators on it as well as functioning as a super tall cell tower for a large area it might be useful. The challenge would be getting the power down efficiently the long tether.
Excellent idea, can add solar and advertising billboards also
I am thinking of being used in remote areS where conventional electricity is hard to get like the arctic or third world countries. Quick to set up. New technologies are always expensive at first.
@@jbird6609 ads are a stupid idea, keep advertising out of the skies
@@user-fs9mv8px1y Its not a stupid idea, Advertising pays big money, About the same as having a billboard along the road and that seems to be ok? Otherwise i dont like the idea either.
It erodes the environmental ambiance.
Interesting idea, I have given it some thought since your last video about it, I still think most of my initial reflections are relevant, for example I still think most projects focus too much on chasing energy efficiency over cost efficiency.
I'm still skeptic about using crosswind, way more energy to harvest, all else equal sure, but also way more difficult to make it work, especially reliably, which should be pretty obvious to anyone by now. A non-crosswind unit that stays up can harvest infinitely more times the energy than what a crashed crosswind unit can. I suspect crosswind utilization represents the majority of what makes heavier than air systems more difficult than conventional wind power at same scale.
A case that I don't think, but know they chased theoretical efficiency in vain is that balloon funnel. Lighter than air wind power systems should be shaped like airships, to have some chance of working practically. Just increase the rotor size to get higher output, that's not difficult. It's much easier to have variable pitch than make a balloon funnel adapt to varying wind speeds. An airship can be made big and also have solar on it. If it's made tough enough to operate at very high wind speeds at high altitude, it could just be lowered if the wind increases too much at normal operating altitude.
i really like the airship idea. Proven technology that should be easy to automate
Hi Rosie, I had a Teams meeting today with Skysails, Hanover, where I put forward my concept of a seabed anchored rotating ring of 500 x 400sq mtr tractor kites. They were able to confirm that their autonomous controllers could reliably control flight in all points of the compass and that such a concept would generate hundreds of not thousands of megawatts/hr...All I need now is investors with deep pockets!
I can see a small scale version being used on sail boats for electrical power. Sailboats already have masts, travel within certain angles to the wind and are often quite far from populated areas, hence most of the disadvantages would be addressed and the smaller size of the equipment would be an advantage plus the trend for sailboats are towards hybrid sail and electric auxiliary propulsion. The forces transferred through the teether should assist in the sailboat thrust whereas generating electric power through the propellers increases the drag on the sailboat. Cameras, lidar and radar could also be mounted on the airborne generator to help AI detect semi-submerged cargo containers and other navigation obstacles that are increasing every year (sonar are ineffective against obstacles close to the surface of the water).
Probably not though.
A much simpler solution for sail boat is to just attach a generator to the propeller that they already have for motoring up to docks.
There are already hybrid and electric drive systems for sail boats that do this.
@@joashparker8271 Well, we already have electric sailing yachts that can use their props as a regenerative brake to trickle charge their batteries while under sail but we also still have many more sailing yachts with wind turbines and solar panels so one solution doesn't obsolete others. Besides an electric sailing yacht are designed and built as such whereas something like the kite turbine is portable, compact, accesses wind at altitude which are stronger and does not brake the sailing yacht but may actually add to the thrust that the yacht receives from the wind.
Interesting, thanks! I wonder how they'll deal with air law especially if those kites go near or above 500 ft. It would also be interesting to compare long-term costs vs ground turbines (which I think is controversial for those), the production per occupied square feet, and the perceived nuisance.
About the birds, I thought they were fast enough to avoid most of propeller-based engines, I had no idea it was significant. But then, many are also killed by power lines...
Not a problem above 500ft. There are restricted flight ops areas all over the world, including over all military bases, most if not all Nuclear power sites, parachuting areas, every NFL football game, the White house and on and on. They get published on airspace maps and if they are temporary they go out with the local area notams.
@@johnway9853 I know that, but that's generally not abused and as you said, it's mostly temporary events. I've never seen many of those restricted areas when flying so it's rarely a bother (mostly some pesky drone areas), but if we need to deploy as much AWE as necessary to replace conventional wind turbines though, that will complicate the airspace significantly. Maybe it's easier in the US, but smaller countries have more complex airspace structures too, where it's common to have close CTR that don't leave much room in-between. Having such restrictions would effectively cut a lot of routes to GA traffic where they are most needed.
@@phenanrithe Every tower I controlled in, all 7 of them, had some sort of permanent restricted airspace nearby. The tower I retired from had a military base directly abutting us so the downwind for 09 had to be kept tight so as to not cross the line. Not like these things are going above FL180. I can see the point in some of the tight EU airspace but even then... as my first on the job ATC instructor used to love to say, It's a big sky. ;-)
@@johnway9853 Well, it certainly didn't look big where I learned. Squeezed in the term that comes to mind.
@@phenanrithe LOL, I know what you mean. In 82 I got my PPL before going to ATC school. The difference in perspective is gigantic. My last tower was also a training tower with more Katanas than should be allowed in any one place on the planet. I figured these kites aren't going above a couple of thousand feet or the weight of the cables becomes an insurmountable issue. Add a couple more thousand on top like built up area rules, and it still makes it less of an issue than many of the snow topped granite barricades out where I started my career. Many a fuselage still on the sides of those mountain passes.
So, I'm thinking:
- helicopter
- triple-redundant autonomy. First two controllers are copies of each other in terms of processor and software; third is separately engineered and can safely land.
- becomes gyrocopter when in the wind up high.
I'd say you got it all right. I especially like your focus on the bottom line. Too many videos about promising new technology which say that the details should be easily worked out, and then you never hear from them again.
Back in 2012, I designed a kite that would have the generator and prop framed in its center. It was supposed to be tethered to a station below, using an Adruino and anemometer to allow the kite to catch the wind in any direction (making corrections as needed). It was of course, all drawn on printer paper at home, and I had no idea how I'd make it or afford to try to make it back then. Now, I am hesitant to re-visit it, in fear of looking like a dumb dumb. lol Maybe I will build a scale model of it one day, and just take my pick up to a back road, in the mountains and try it out. lol
u should. keep me posted if you do
I just discovered your channel and really like it, thank you! I am a mechanical engineer myself and once unsuccessfully applied at enerkite, which also develop a airborn wind harvester, in 2016 or so. Since then I've been following there newsletters. Unfortunately, few things significantly seem to have improved, as they mainly ask for (crowd)funding. They plan to offer up to a 2MW units and do successful testing (since years, whatever that may mean...) and hire new technical personnel. So maybe they are worth checking them out once in a while.
Thanks Rosie for this interesting video. I’m a founder at Wind Fisher which is a newer entrant into this field. We resolve some of the issues you mentioned by using lighter-than-air, crosswind capable, Magnus effect balloons. I’d be happy to give you more details for inclusion in a future video. Kind regards, Garrett
Hi Garrett, I did see Wind Fisher and thought it was interesting. So many cool physics and engineering principles in one device! This video was intended to be on the more more commercially mature systems but I would be interested in Wind Fisher for a future video. Did you test a prototype yet?
It's a failed idea. It's too complex for power production. Ground based and ocean based wind turbines can and will get much bigger. Giant flying generators on a cable are impractical and the size is limited by physics. The safety margin required would require a huge cable for a megawatt sized flying turbine. The fastest growing and most successful green energy technology on the planet is ground/ocean based wind turbines. Just one of the new large turbines has made more power already than all the flying/kite wind turbines in history. Some ideas that sound good are just dumb. This is the solar roadways of wind. Countries, utilities and individuals build wind turbines because they pay for themselves within 3 to 5 years and make cheap green power for 20 to 25 years. They make money! Maintenance on electric wind generators is easy and equivalent to annually changing the oil and filter in your car.
Ha ha, solar freaking roadways!
Too bad. Its really neat and makes sense. Maybe the trick is to reverse the endpoint to be useful for space powering
Perfect explanation. Offshore deployment of windmills complying with much bigger power factor generation. That is what we are studying in Brasil as in other places too.
Your summation of the issues with kite power share a similar flaw that plagues not only this review of the tech but most of the energy tech media today. Rather than focusing on the merits and difficulties of the tech in question, everyone gets lost comparing apples and oranges, as if only a single company is going to supply one type of turbine to the world.
@@malachiteofmethuselah9713 my friend! I used to work as a project engineer in renewable generation for most 30 years. Despiste the merith, this kite technology is far beyound the energy challenge we are facing in world. And its not me that Will condemn an idea, the time and the payoff will do so!
Engineers see solutions in everything, but they often fail to grasp the downsides and potential problems with tech they develop, for example, lifetime cost vs upfront costs, metal tends to break apart when stress and load is put onto it, i see ONLY problems with a 24/7 flying structure that is suppose to last decades and reliably feed power to a grid that everyone depends on.
A nuclear powerplant lasts for 50+ years, it's solid as hell and will probably never run into major issues during its expected lifetime, If i was an engineer i would focus my efforts into making nuclear powerplants better instead of this artificial tax-fueled wind power hype, if windpower could bear it's own weight in infrastructure costs, powergrid costs, no tax incentives or "green politics" what would be it's current price per kWh? and electricity can't really be stored cost-effectively, we should only measure price per kWh during windpowers minimum output days during a year and not peak production days)
Start thinking stability and not fancy tax fueled green stuff please.
This is my favourite kind of alternative energy generation 😁
Could you smooth out the spooling/unspooling energy load by funiculating two together?
"Funiculating" two together sounds like you want them on connected tethers? Sounds like a nightmare for fouling and knotting.
Rather you would have multiple units with distinct ground tethering points, far enough apart that the lines do not risk getting entangled.
Since reeling in can be done much more quickly and under lower tension than the long crosswind flight which pulls the tether out, you would probably want more than two.
I vaguely recall an early proposal that had multiple units moving at intervals along a loop railway track, probably using ground traction in place of constantly reeling out and back in. The advantage eludes my imagination though.
I don't need you to give me the right answer when you don't have it due to too much uncertainty. I'm blissfully happy with you explaining pros, and cons, and considerations. Just keep making them. I'll watch them all.
I was originally going to say that this concept is fairly stupid. After reading further into it for about 1/2hr or so I can see that there is potential there but the whole thing relying on winching in and out about 500m or so of a 1km long dyneema cable every 2 minutes 24/7 is a fairly obvious failure point.
For ground generation, why don't they use *two* kites pulling back and forth, slightly offset through aerodynamics so as not to get entangled? that way you wouldn't have to use power, just adjust aerodynamics mechanically to switch back and forth
There was a company called KPS who did that. Most of their IP is now with Kitemill
That's mechanically more complex.
If you consider the grid to be a power source, as well as the place you stick your generated energy, then it's fine to use a bit of grid power to pull the kite down and to thereby benefit from the mechanical simplicity of managing a single-kite generator. You can consider the periodic wind-in energy to have come from one of your other nearby generators which, in the big scheme, all averages out into acceptably smooth and reliable generation for the grid.
@@Rich-on6fe thanks. Yup, sure. Intermittency is no issue any more, we know how to deal with it. It just *sounds* like an inefficient way to do it, but at the end the numbers need to check out. Not always intuitive
Wish theyd try to make these smaller instead of bigger. Be pretty cool to hook a kite to a catch on a generator for emergency or remote power gen where solar isnt viable.
We're the guys who are developing a small, cheap 1kW version ;)
@@kitesforfuture577 awesome!
11:32 Oh you teased us a bit there. 😆
Is there any research being done on using a Lighter Than Air (LTA) device as a means to assist launching, the airborne part?
And/or synergistically using existing or new tall structures, such as cellular or radio towers or even buildings?
Great question for the livestream!
@@EngineeringwithRosie as an addendum.. If you could. please ask about the possibility of deflating the LTA, such as via hose? to make retrieval easier and more controlled...
Since I don't believe I'll be able to be online during the livestream... Good luck with Livestream....
Have you investigated much into kite-line drag? It is my understanding that it was underestimated, and turned out to be one of, if not the biggest impediment towards competitive efficiency. I'd be curious to know what the industry is doing. Once solution could be to create some kind of kite-line sheath that had a winglike cross section... in theory....
On notorious Makani project had been spent millions of dollars. Shut down. It is a stillborn idea and in absolutely no way it's "less material".
As you say it all comes down to the cost of the electricity produced. I would think they could operate the generator platform as a conventionally powered drone so it could take off and land and maybe power up if it had to for weather conditions but operate as a glider at other times but this would add to costs. It is a pity because it looks cool.
Why not instead of reeling it all the way back in, just have a dual-kite setup where as one extends it pulls the other in by being physically connected to the spool in the opposite direction. This way one when reaches its limit of length, it folds its wings in to a gliding mode and the more pulled in kite unfurls its wings for maximum drag.
This could allow both kites to remain up in the ideal airflow zones by limiting the phasing distance too.
Energy would then be mostly consistent as well.
Jets are not a good comparison because they are a military first technology where achieving greater capabilities is much more important than economic viability.
At 05:33 you state that in this study, “the local bird population was only active at night”. This literally cannot be true. Nearly all bird species are only active during the day because nearly all bird species cannot see at night. Owls are a very rare exception to this rule, but there is no place on the planet where the majority or all the birds are only active at night. This runs completely counter to everything we know about bird physiology.
Emergency power generation does at least seem to be one viable market since it has the advantage of not needing fuel over regular generators. Of course there's still solar it'd need to compete with, which might be hard given how dead simple and reliable solar is, it'd need to produce significantly more power for its cost and area used.
Thanks Rosie for the presentation and comments below.
I think a smaller version for a home trial would be nice as a test unit although I don't have the wind in my site to test but it would be cool to see a sail in the air.
Keep up the good work!
Good to see that such a technological diversity exists ! Who cares about bankrupt ?! Those technologies will survive because they're efficient enough to do so.
Makini style:
I made something similar as a kid, but with more dihedral and sweep back. That gave me stability WITHOUT the need for computer controlled control surfaces.
As for yaw stability: dragging a (bigger) propeller behind the tail, (or the main wings to a lesser degree IMHO) gives WAY more stability than having the prop try to 'push' yaw and pitch into the plane all the time.
With this design it's almost as if the university/students wanted instability so they could say: "Look at our clever computer control system!"
I had my model flying stably on the end of a fishing rod/line for sucks fakes!
The only adjustment required was where the tow hitch is relative to the wing's center of lift:
Want too land: move it to the nose.
Want to take of: move it slowly from in front of CoL to slightly behind CoL.
"A solution looking for a problem" is what I see here.
If anyone finds this interesting: I would love to be involved in a KISS version of this idea.
A couple decades ago I floated this idea to an aerospace friend. He had a fit about airspace control, blah blah blah. It's that group that will protest the most about stuff invading "their" airspace, as if it belongs to them and them alone.
Hi Rosie, Great coverage of AWE. Please look into many-connected Kite Network topologies as the ultimate AWE scaling principle at highest density and safety, and also note that modern architectural and airplane fabrics are now certified for decade-plus service-life.
Great questions for the livestream. The really durable fabrics aren't used for kites yet because as I understand it they are much more expensive and it's cheaper overall to replace a cheaper fabric every 6-12 months. For now anyway, hopefully that'll change.
I remember watching a documentary about a team building one of these things and it was fascinating. The team was so bright and hard working but their financing ran out right when they found success and so they had to mothball it. I do think that the complicated control systems probably mean that it won't be a big player in the market, but, where they make sense, they'll be hard to beat once someone makes a truly viable product.
Google bought em and shut it down, so sad.
@@Deaner3D There's a doc about it, “Pulling Power from the Sky - The story of Makani”. Using the sky is probably not the best option. Imagine the same thing, but under the water. There's a number of different tech being explored, but something like the Makani in the deep sea flying a figure 8 could be interesting.
would it be possible to use a large airship to meaningfully, without great expense, reduce the draft of a oceangoing vessel that is laden with cargo and thusly reduce fuel costs?
i love the bird argument. suddenly everyone is a birdprotector. until you mention that cars kill million times more birds than windmills.... :D
Ultra High Flying Tetrahedral Kite!!! Create a Incredibly Massive Tetrahedral Kite that has thousand's of tetrahedral's, and place thousands of incredibly small wind generators in each of the individual tetrahedral's themselves within the kite itself, and route all the incredible small micro wires to a main location, where they all feed their electricity simultaneously together, and build the voltage up, and then direct it down the kite cable, and to the generator on the ocean ship!!! I Hope This Helps!!! And as far as I know none of this is copyrighted. Here is a video on Alexander Graham Bell's Tetrahedral Kites from 1903-1909 more than 100 years ago!!! For Study Material!!! Clean Energy For All!!! ruclips.net/video/BhwgOv8Mfyc/видео.html
Logistics (crossing tethers/tangling) would make scaling to large enough facilities to be economically viable "difficult"? Fixed wing would be vulnerable to "icing" phenomena the further away from the equator they're sited? Torsional power conveyance to the ground is fraught with "challenges"?
I like the added energy available, and "noise" reduction, and relative reduced optical "footprint"/viewscape littering (until they crash), but many challenges lie ahead IMO..
Germany already wasted 430 Bln Euro on wind parks on the Dogger Bank before realizing that low availability is the major problem with wind that can not be overcome. On 430 Bln Euro Germany could easily built 90-120 nuclear reactors to cover 200 % of energy demand of whole country. Who pays for all this "wind" stuff?
Hey Rosie, what about stratospheric units that when failure occurs, they set off an ejection seat rocket while dropping the tether. The unit could go orbital till reaching an uninhabited drop point. Auto rotor programs could land it. OR.... let'er burn. LOL You know they will be all up and down the "Space Elevator" Do you think we will give these things highway names and numbers????
All I heard was......., fringe tech not likely to go above critical mass, because it hasn't, might be good Engineering, but insufficient demand from those with adequate funding. Keep trying.
But "go fly a kite" will always be fun..
Shame that the Makani went out of business, I was really rooting for them.
These kites would be PERFECT for remote locations like islands or small settlements as their size and footprints are small(er).
No need to upscale them, they could really corner the market at the 100-200kW segment perfectly.
I designed something similar about thirty years ago. There's nothing technologically wrong with the idea; it has some obvious advantages over conventional turbines. It's a bit complex, but I think combined with a robotic controller it could be quite successful.
That's what I thought 3 years ago and then we built and open sourced it.
Why not set up panels of LITTLE pinwheels, on the sides of large buildings that often have strong winds hitting them, BUT instead of empowering electric generators, each pinwheel has a little air pump, that propels air through one-way valves into a network of tubes or pipes, collectively expelled into a SINGLE large scale turbine that turns an electric generator?
Keep exploring at brilliant.org/EngineeringwithRosie/. Get started for free, and hurry-the first 200 people get 20% off an annual premium subscription.
I'd like to see a comparison between the impact of (domesticated) cats and renewable energy on birds. "Some information suggests domestic cats pounce on from one billion to four billion birds a year in the lower 48, six billion to 22 billion small mammals, and hundreds of millions of reptiles and amphibians." So this kind of arguments should be put into perspective. This means that renewable wind energy kills "only 0.1%" of birds compared to cats.
I really hope "optimists" of all shades, understand the Impossibility of both windmills and kite windmills.
The chance of these kites surviving more than a few weeks is minimal.
The land area under threat of falling objects is vast.
The whole idea is "utter fantasy", and Childs play. Very expensive Childs Play
Elon, King of creating fancy stuff for making the future interesting, should continue Makani. They have a huge documentation on youtube which was REALLY fun to watch. So maybe he can continue their story and he might eventually end up with something that works. Rocket powered kite ascent on no ground wind anyone? ^^
The solution of a blimp/dirigible seams like a natural answer to most of the design-dilemmas: Still mostly soft-body, but more rigid than kites. WAY simpler take-off, landing, and maneuvering than airfoil based flight... especially if it were ground-based generation as the balloon would basically need to be a buoyant sphere... same cross-section regardless of orientation of the balloon to the wind. Similarly, low wind at ground level is no barrier to lift, as the lifting capacity of the aerostat is independent of wind-speed. Yet your video indicated that only company that had tried a lighter-than-air solution had gone under... why?
There are certainly big issues with this. To get economies of scale you need big power outputs per machine, in the MW at least. Having a flying machine that operates autonomously but is big and heavy enough for multi-MW generation seems unlikely. AWE needs a lot of space (or ever more complex systems to avoid collisions) so the MW per sq km is likely to be limited.
For me the big problem is that we are trying to replicate the huge controllable energy outputs that have been possible using fossil fuels, big hydro, and nuclear, replacing them with intermittent location-specific sources difficult to scale up.
Ok... It even could use much less materials but, the tridimensional SPACE required to operate this is absurd... I really doubt that the farmers and people that already complain about wind farms (visual pollution, sound and stuff) will be happy with this. How about a kite that have its cable snapped, what they do with that? ANd those techs does not seems simple or cheap at all.
I think the bulk of wind energy in the far future will be ionic wind generation. If they can get it to 20% efficiency, then anything else will struggle to stay viable. I could see a kite using ionic generation instead of a rotor, but I could also see an existing ionic wind generator that can generate in any environment, even a hurricane. We could see something like planet exploration where a kite could be used. There are already designs on using ionic wind generation on existing rotor blades to increase efficiency past 50%. I'm not sure kites would survive the NIMBY factor, even in remote locations with few houses. You wouldn't believe the push back in America's second least populous state of Wyoming for wind turbines.
If you are ever unfortunate enough to break down on a motorway, you will find that while standing on the hard shoulder, you will be battered by a constant strong wind from the slipstream of passing vehicles, especially trucks. When I am out walking on a windless day and then walk along the motorway feeder road near where I live, I get blasted by a strong wind from the passing vehicles. Is the UK Government missing a trick, by not lining motorways and fast feeder roads with vertical axis wind turbines, which will generally be turning all day and night from passing vehicles, regardless of atmospheric wind conditions?
Hello,
I see any attempt with a kite kind of fruitless.
High level wind generators are only feasible with in-built buoyancy - i.e., a turbine generator on a tethered blimp.
With a multistage turbine it is possible to extract a large amount of energy from the wind, and protecting the blimp in the meantime. A set of gyroscopes (reaction wheels) would keep the surfaces in the optimal position, and protect the whole generator from sudden wind gusts.
Greetings,
Anthony