A homemade flying wind turbine to power your adventures.
Let's make an energy independent transport. We'll add kite power to an e-bike or e-car. And Let's have spare clean power for your situation while we're at it.
Kite Turbine networks can enable low carbon energy and being lightweight they're transportable. The networks are modularly scalable so tweak the parameters right and we may have some real utility energy on tap.
With so much energy potential - SAFETY ! WARNING ! This is experimental !! Carelessness kills! There's a lot of safety to consider before you try this. Don't go getting all excited. With that in mind I'm going to lend it to a bunch of kids.
Right, I better get on with project log entries, see you there soon.
Details
A scout troupe asked me for a kite turbine, for a scout Jamboree in Austria. Why Not?
Significant improvements in power, weight, portability, strength, control, data collection, deployment, smoothing, scalability, designs, efficiency ... Merit an update. The new power to mass ratio (>300W/kg flying material) means these turbines can be incorporated into transportation, enabling energy independent vehicles. Lets do that.
I blog my kite power adventures on windswept-and-interesting blog where I post progress on kite turbine powered transport, including e-camping, kite kayaking, e-bike cycling, e-car driving.
The kite powered e-car challenge is already going on. It's a big scary amount of power to be working with. For this project, I'm going to concentrate on something safer and more accessible.
By adding a kite turbine, I'll have an energy independent e-bike and a useful power source. Something suitable for powering a camping adventure. E-bikes have all the electro-techno-gubbins we need, a motor for regen (Yes geared hub motors too) a controller, a battery and power distribution.
Components
1×
VESC6
The VESC (Vedder Electronic Speed Controller) will save you grief. It's an amazing motor controller. pricey though.
1×
E-Bike wheel.
Normally I use direct drive motors for bike wheel power extraction. This time we're taking kite power directly to the wheel rim & I'm modifying a geared hub motor with the planetary clutch fixed to be engaged.
1×
Jullet cable or other e-bike motor cable standard connector
To tidy up and make a bit of an extension. Type dependant on what motor standards you go with
12×
2m x 5mm GRP or Carbon epoxy rod lengths to make the torque tube and top support rings
You will need varying lengths of this for different rings ~12 x 2m
1×
Dacron tape
for leading edges, line tapers, webbing, seams, joins, ring cuffs, anything sew-y
On all previous models, the lower, smallest hoops, were made and sewn in to the compression sleeve. This means they were a fixed size radius. Trying to package this is tricky. As seen in my previous logs.
So, I've made a whole new set of rings and lines for the "torque ladder". Every one of the rings now comes apart. The rings are all made with the same 170cm carbon rod. The advantage here is you can now package all of the kites, all of the rods, all of the lines rolled together. They now fit inside tube carrier I made by modifying a pair large extendable poster tubes. (Two larger diameters fit over one smaller diameter central piece)
The lowest 3 rings (nearest the generator) have 1 rod, the next ring has 2 rods, the third ring has 3 rods.
Deployment is easier now, as you can unroll the complete set of torque tube lines and rings. Photos to follow. And the lines have less knots on their way down. The whole thing looks neater.
With practice I've neatened my old kite turbine designs.
Make neatly cuffed compressed rod rings as follows
A length of loop inside the end of a compression cuff
A length of hook over the top past the other end
This length extra cuff longer than your rod (2 rods or 3 rods) length is great
The singles, a double and triple rod (1.7m x 4mm carbon epoxy, both ends with heatshrink, one end with a 10cm cuff @ 5cm epoxied in place) into a ring, compressed and closed in a cuff. The single rings have been sewn shut at ~26" ~62cm, Now our minimum packing box dimension.
These rings now need a 6 point harness to a ring in the centre. I made the small white food grade plastic ones, (seen in the boring video) with 3 rim holes for harnessing and a central hole for the central lift line.
Then you need to add tabs with 6 tethers to rundown the stack from ring to ring.split rings
The screwdriver blade was sharpened to help opening the strong split rings. The tether at the top comes from the kite, down to the split ring tabs, web supported past the inside of the cuffed ring and on down to the next ring.
This is the tether from the kite ring. You see a double tab and split ring connection on the ring in front of the kite. That allows the ring kite to fly configured as a single, double, tripple anywhere on a stack of ring kites. Only 3 tethers (black dyneema 2mm 230DaN) come down from this ring. The kite is attached, front and back, to the ring, with webbing strengthening the joins at about 3/4 span. The tether progressively bridles to the kites original bridles. The outermost bridle pair have a longer lead form the main tether. The inside leading edge of the kite has a 3mm epoxy rod to set the leading edge tight.
You're pretty much good to go at this point.
Some young scouts managed to power kettles with it so can you...
Connect everything, throw it in the sky and get power.... well... that'll take a bit of practice yet.
I'll come back soon with more details of how the packing case system progresses.
I may yet change down to a 20" wheel for portability. I also want to make straps so that we can use a wheel which comes off, gets used, then goes back on an e-bike. The battery I use here is from an old motor which has now been incorporated into a powered drift trike. We have used the kite power to run it. But I don't recommend that design..Deadly.
I still have to attach (rivet) the No-Wind cranking handle to the wheel rim ( I want to call it a winding handle since there is no wind) I'd only do this for the scouts camping model as who needs a handle flying round on an actual bike wheel?
Thanks to Robbie from Gordon Diesels for designing and making a new post clamp / generator mount. This is magnificently simple. A sheet of aluminium (walkway) cut with a water-jet then folded & welded. The central slot holds a bike motor / generator shaft. Straps hold everything to a post.
Now we have all we need to hold the kites while allowing them to spin fast. Kite torque energy can now be extracted as electrical energy at the generator.
Fold the 4 webs and seam weld. (I've added 14 extra suggested hole locations (to this .jpg as splodges) to aid tying off onto flying pole or ground stake architecture. Will try get the cut pattern for you.)
A much nicer running geared hub motor
I also got a new motor from Charlie And Seumas. There was one wire broken in the plug. Not a problem I cut the plug off. Made a wee tig weld on the planetary gear casing. Replaced and tested. All going sweet on VESC 6 test. Packed with grease.. it even has a wheel. Sewed on 6 strap tabs with ropes. Figure 8 stop knot at an equally measured length.
Here's the technicals on getting regen from a bike wheel.
How to put a torque tube together (The boring video)
Wow that was dull, but you did get a look at the kite and torque ladder construction.
Lets go out and test. Finally you get to see flying and clamp v1 in action for the first time in this video.
Finding my fortune on the Shore
Packaging these turbines and the generation kit for travel is challenging. The smallest rings on the torque ladder are 62cm dia. They don't come apart like the large rings (yet), So somehow we need to protect that for travel. 62cm is big. 62cm is also ~the size of the 26" mountain bike wheel I was given. It's not easy to find standard packaging or storage boxes to fit that. However, if you happen to live on an island with plenty aquaculture, Giant mooring buoys tend to frequently wash up on the shore through the winter. Yes, I had these in my garden.
You will likely find some other kind of large plastic cylinder (maybe a garden water butt)
If not, first cut enough end off to protect your wheel, rings, motor and gadgets.. then scrub the barnacles off, and remove anything which still smells like an octopuses nightclub. Clean up the plastic sawdust.
I bought a nasty old geared hub e-bike motor on ebay. 36V and 36 Spoke. 36V because I have that battery, 36 spoke so I can easily tie 3 or 6 kite lines neatly to the rim.
I chopped off the Julet plug, I couldn't find a wiring diagram online and I had no socket. So incase you do have a socket already... Don't bother here's a picture.
I opened up the motor, blew the ming out and removed the planetary gear to see how I could go about locking it off. As you can see in this photo, I was waaay too brutal with using an arc welder on the thin casing walls of the planetary gear freewheel... I melted the gears a little too. (use a TIG or other small welder)
With disregard for what went where, I hammered (a lot) the messy non-freewheel planetary hub back onto the shaft, and it broke a bit, but it wedged into the motor casing. The whole thing turned with terrible grinding sticking noises.
Until I connected it to a VESC 6 that is... When it started to sound sweet.
VESC 6 is a phenomenal motor controller designed by Benjamin Vedder and sold by Trampa Boards. It's not cheap. ~£300 GBP. However it's super fast, It walks you through motor setups for Field Oriented Control, It gives you plenty of control interface and motor parameter options to play with. The VESC 4's are open source hardware too.
You can see in the twitter video, I added a thrust bearing (skf 51204) to the motor shaft, this holds the casing from being pulled forward by kite lines and destroying the normal motor housing bearings.
Now find a rusty 26" 36 spoke wheel your neighbor has left outside for ~3 years. Cut it to salvage the rim. I was lucky, my motor came with a set of spokes. I was unlucky, they didn't seem to fit. I made up a spoke pattern so that they did kinda fit and it worked - ish.
If you have to get spokes, using ebikes.ca calculator can help.
The motor and wobbly wheel need held to the ground to hold the kites. We also need the axle to point at the kites but not turn. I rivited a rough u shape section of mild steel to a set of bike handlebars. (keeping with the minimal transport theme.) The steel had a slotted hole cut to fit the flat sections of the shaft. Good enough to hold and generate.
Interested to see how long this survives. Expect work on a standard e-bike wheel and handlebar connector soon. pic.twitter.com/DYvXAjjWmN — Roderick Read (@rodread) June 20, 2018
After a basic wheel truing (see Sheldon Brown for expertise) I attached the 36v Bike battery and VESC6 to the handlebars. I configured the VESC 6 using VESC Tool so the application used a 10kOhm pot connected into the ADC1 of the 8 pin JST connector for speed control. I also set very timid limits to the speed and the current in the VESC Tool software.
I readied a kite turbine I had lying about... (you likely have to make this bit) We'll cover that in a later project log entry. I also made an extension cable for the battery cause it was very heavy to hold. I fitted a windsurfing harness to the bar... for options. (You can actually run these turbines with the motor as a great big tensile prop...interesting games ahead.)
I'm Roddy, an engineer, teacher & househusband who loves the ecological ideal of kite power. The practice and development of kite power is harder, but doable. (Older Instructions)
I see massive benefits in using kite networks for Airborne Wind Energy Systems (AWES.) I design, test and openly publish details of my kite work. To read more on AWES I recommend Here and Here. I also recommend the new Springer AWES book (I'm Chapter 21) I started Windswept and Interesting Ltd to develop kite power. (Overview of W&I)
Network kites are very different to the other AWES schemes. Networking kites makes them stable flyers. Extra lines make networks fault tolerant and fail safe. Networks give you more kite per line drag.
This is a network kite turbine. I call them "Daisy". It works as a multi-stage, tilted, hollow axis, tensile auto-gyro kite turbine. (If you're keen, this work is in conjunction with Oliver Tulloch's PhD at University of Strathclyde.) It uses a central axis lift line to guide and limit the travel of the rotary blades.
A recent long exposure pic of my Daisy kite turbine flying at night. Flash exposed the lines and kites, a torch exposed the rotor motion of the middle ring of kites.
Idea and Challenge
I've been asked to make a kite turbine, for local scouts to take with them, to an International Scouting Jamboree in Austria this year. The scouts have an eco camping challenge.
So I need to make this light as possible and safe to transport. Compatible with an e-bike will be a real bonus because even kids can work that regen tech. I want it to be capable of powering the bike itself and some camping gadgets. (Heavy juice ones like an electric kettle as well as USB toys.) We should be able to do this, the kite turbines have been outputting ~300W/kg flying material max so far.
I want to dual purpose as many bike parts as I can without killing bike functionality.
Having said that, I'm going use a small geared hub motor and wheel to convert rotary power to electrical power. Using a small geared hub motor for regen may be controversial among cycle purists as there will now be a cogging resistance if you cycle without using the motor. (why would you? E-bikes are amazing fun with the motor on). As explained here you have to weld or otherwise lock the freewheeling planetary gear for regen to work.
A couple whacky but possible extensions might be possible for this project. 1 Use the kite powered up from below for turbo fan propulsion (sounds fun) 2 Host the kite turbine in a tensile aerial network
Resource
I'm lucky to have a family who let me be a househusband / mad scientist. I'm no positive on the domestic balance sheet so I keep the budget minimal. This allows the projects to be fully replicable. I do spend on the motor controller for this project. (VESC6 has a very good open source hardware history and cheap derivative alternatives are available) I also spend quite a bit on carbon tubes. Cheaper fibreglass rods have worked on designs I've shared before.
Oliver Tulloch and I have a small budget for parts from ETP Scotland.
Plan
Whilst helping Ollie with his PhD, it has become apparent that, Daisy can be an efficient and clean way to to source energy at scale. Our much larger prototype had 30kg CO2 emissions equivalent in production, the complete prototype has a predicted carbon cost of energy of only 17g CO2/kWh in year 1 (already better than solar over its lifespan) and only 1.7g CO2/kWh with consideration of replacement components thereafter.
So we have been having fun making and testing both physical and mathematical models.
As for sticking to a rigid plan... Maybe. Reminds me, We're going to test more rigid rotor wings soon too.
Check your weather forecast (windy app) shows a consistent direction of wind at a safe speed (Below 12m/s or 27 miles an hour) for the whole time you intend to run the kite turbine.
Find a good open space. Try to avoid having buildings or trees upwind of your site. They cause wind turbulence, which will considerably diminish generating performance. Setting up in short grass is a lot easier.
Check the equipment is in good order.
Coordinate your plan with camp organisers and communicate with base (Whats app message)
You will be using 1 tree (Or pole) to hoist the top end of the kite turbine into Clear Air.
Choose a good tree. It should be safe to climb and have space upwind to “fly” the hoisted kite turbine. If necessary, a hoisting line can be slung in the space between 2 trees.
Tie the strop around a good branch and attach the hoisting line & pulleys. Ensure there is a place at the bottom of the tree to tie off the end of the hoisting line. On the ground, walk the hoisting line upwind from the branch, to a hoisting point, clear of the tree canopy.
From this hoisting point, walk a further 17 paces (at least) upwind (toward the wind) and drive a suitable stake angled into the ground (Down end = downwind, Top = upwind)
Drive a screw anchor into the ground about 1.5m further upwind from the stake.
Strap the clamp (with generating wheel) to the top of the stake, with the wheel facing the tree.
Tie the top of the stake back to the anchor with the spare length of strap.
Plug the control cable into the motor / generator (The two arrows have to be aligned)
Find a secure place to keep the control box while the turbine is running.
Open the tube, remove the rods and sail bag.
Lay the rods and sail bag on the ground near the base of the stake.
Unroll the net of rods. Closest to stake = 1 rod then, 1 rod, 1 rod, 2 rods then 3 rods.
Firmly hold the first single rod at both ends. Bend the rod into a ring. Make sure to plug 5cm of the thinner rod end into the socket end.
Pull the black sleeve tight around the rod, then close the sleeve with the Velcro.
Check the black lines are on the inside the sleeve.
Make each of the following rings in turn. 1 rod, 1 rod, 2 rods , 3 rods.
For the 2 and 3 rod rings, it may help to remove rods before reinserting, to make sure the sockets and plugs fully engage.
Check the rings are free of twists, all 6 black lines run neatly between the rings.
Connect the small end ring onto the generator wheel using 6 larks head knots.
Remove the top lifting hoop from its bag, and make the 2 rod hoop as before.
Check the top lifting hoop has a top cone and 6 lines for the kite ring.
Now for the kite ring. Yay.
Remove the kite set from the bag. Lay the kites on the ground in a radial pattern. Remove the connecting sleeves from the kite pockets and stretch the kites out, as a ring on the ground.
Find the break and connector in the sleeve. Push the first of 6 carbon tubes into the sleeve. (These tubes will not bend as much as the rods. Carbon can be brittle when handled rough. Take extra care where you step near these tubes.)
Inset the 2nd tube into the first and continue until all 6 tubes are in the sleeve.
Fit the end of the first tube into the 6th tube to make the ring.
Tighten and close the sleeve together with the fastener.
Make sure the ring of kites is the right way up. (bridles to the bottom)
Remove the kite line from a kite pocket and stretch it out to make sure there are no tangles in the bridling. Attach this kite line end of one of the 6 attachment points on the large ring (3 rod)
Repeat this for the next 2 kite lines. Remember to fit the kite line onto every second attachment point. (3 kite lines won’t go onto 6 attachment points. Making sure to leave a gap)
Bring the top lifting hoop over and lay it on top of the ring of kites.
Attach the 6 light lines onto the 6 short white lines on the top of the ring of kites.
Now is a good time to pull back the hoisting point, to stretch out the whole kite, so you can check each line is run smoothly and there are no twists in the hoop sleeves.
If there is a twist, remove it. You may need to open a ring, or even remove a rod to remove the twist. Then reassemble as before without twists.
Stretch out the central lift line. Attach the bearing end of the central lift line to the hoisting line.
Thread the central lifting line through the top hole. Tie a figure 8 stop knot at the red mark nearest to the bearing.
Thread the rest of the central lifting line through all of the centre disk holes.
At the bottom, tie another figure 8 knot at the red mark near the end of the central lift line.
Use a larks head knot to attach the central lift line to the centre of the generating wheel.
Make sure the battery is in and turned on.
When you are happy, and with everyone aware and standing clear; Hoist the kite with the Hoisting line. Tighten and secure the end of the hoisting line.
The kite should now be turning cleanly in the air without any impacting.
Congratulations, You’re one of the few people on the planet to ever have made kite power.
Keep bags and tubes tidy. Cover the electronics with the tub. Secure the tub.
Be methodical and tidy when reversing this procedure to put the kite away. This will help your next launch greatly by avoiding tangles.
If Austria has insufficient winds for generation, The kite turbine can be removed from the generating wheel, repacked and replaced by the cranking handle. This will allow you to generate electricity from Scout Power.
Roddy "Rags" Read
Andrew Clink
Latest test results over 1 kW
https://youtu.be/UpIECYxP4xc