Bamboo kites

So bamboo is being considered an alternative to carbon fiber composites for windmills.

The question is could it also be a good option for rigid wing AWE? I guess strength to weight ratio is somewhat reduced, but bamboo holds a big benefit related to AWE.

We may assume that AWE would be installed in uninhabited areas such as farmland or forest. That land would have dual use as food production for humans or animals.

For every carbon fiber crash, one will not be able to recover every shrapnel of carbon fiber. If any such shrapnel should make it’s way into the food chain, the consequences would be dire.

Bamboo kites would decompose quickly in the soil.

The situation is maybe not as severe offshore, though who knows if sealife could be damaged by consuming carbon fiber materials

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Oh well there’s a long history of bamboo and big kites of course…

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Just one attempt at a bamboo wind turbine. Using giant bamboo.
I ummec an ahhhhhed then though a little perspective can’t hurt.
Remind me a lot of an old entering tutor I had. Who’s morning greetings was marvellous. Mr starmer, best machinist I had meet up until that point. Probably would have given it a crack as well. No doubt awes would try to get one airborne.

Not exactly what I had in mind…

As well as spar structures, skin and lines can also be more eco considerate.

You get eco epoxy from several sources

Even pre-preg flax sheet

Hemp rope may have a use where it’s a rope running (wearing itself out) over a pulley sheave all day.

The generator and control electronics won’t be easy to clean up, but recycled, maybe but we must keep product scaling in mind

anchor is interesting… that can be a bag underground, which is surely less mass than a steel structure

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Early hang gliders were made with bamboo and sheet plastic. I remember reading a Popular Science article about hang gliding back in the '70’s, featuring “The Bamboo Butterfly”

Bamboo, like hemp and wood, can also be used as a source of fibers for composites, as we see in “bamboo flooring” these days - shaped into planks with tongue-and-groove edges for interlocking attachment.
The one aspect of natural materials capable of changing mass by water absorption is water entering one blade differently than another blade. Water will tend to absorb into natural fiber material, but also bleed or flow out toward the tips from centrifugal force. Water resistance and predictable, effective drainage are important lest a rotor become unbalanced and shake the machine apart. :slight_smile:

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By the way, I tried building a hang-glider from some parts recommended in the Popular Science article - aluminum antenna mast poles from Radio Shack and clear, polyethylene sheet-plastic, and duct tape. It didn’t seem to work particularly well, and did not look promising to safely fly, so I broke down and bought one. Back then it was $450 including a harness for a brand new glider. Later when I read that a new generation of gliders was about to emerge, I sold it to buy a motorcycle, which provided not only fun, but basic transportation. A Honda 350 with extended front forks. Now I was one of the cool kids! :slight_smile:

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I think modern bamboo blades are soaked in epoxy so maybe they wont take in water. Than also they may not be readily digestible :stuck_out_tongue:

That’s how they make the flooring - with Epoxy.
I know both the last guy to make wood blades for the Jacobs turbines, as well as they guy who replaced them with fiberglass blades. The original guy I met years ago and he was already well into his 80’s, if not more, and he wanted to sell me his whole blade-cutting apparatus. He lived in the Ozarks, in a little mountain town that had a central hall where everyone would bring their guitars, drums, etc., and play music all day, and the wives would cook food and every day was a jam party - what a gem of a town! I wasn’t sure how I’d get all the equipment to California from rural Arkansas
I was not aware anyone is currently making bamboo wind turbine blades. Got a link?

No. Im not sure where I read about it anymore. Though I’m sure what I read about was either R&D or a startup, so probably not sonething you could actually purchase at this point

I think I read about these DTU/Chinese blades

If I recall correctly? they dip doors to remove any epoxy and varnish. I don’t know what kind of expenses it would cost to decommission turbine blades in that way? Turbine blades dipped in a chemical bath might also help recover materials? It may help with the recycling aspect? Because once the epoxy been removed, It can be shredded. Then disposed of appropriately. Though I can’t remember the exact chemical used. I do know its done in a small capacity in reclamation yards. Don’t know if this is going to be helpful? Better than land fill or incinerators. If using complete organic material? it can always be composted afterwards. Completing the carbon cycle. Ready for more organically grown materials. Might be the oldest technology on the planet? But its a good shout for disposal. I will let you guy mull on it.

Anyone who has worked with composites such as fiberglass and especially carbon-fiber, knows how irritating to the skin it can be. Even going into a typical attic with all the fiberglass insulation is supposed to require a mask. I have a friend who does HVAC work and he always wears a mask. It is a very specific type of hazardous waste, mostly based on the physical form rather than the chemical nature. Wish I had an answer for what to do with all those old blades. As with old tires with all that steel wire, no good way to dispose of it. Seems like recycling as building materials for roads, roofing etc. might solve the problem. Seems like some stuff is easier to make than to un-make. :slight_smile:

I’m not going to get too concerned yet about water ingres causing inexact matched blade mass.
Yes I’ll improve my work but didn’t notice any effect (was surely there though) using my last set which were out by >1%

On the fibreglass front. Silica is meant to be highly recyclable. If the resins can be extracted? then it possible to smelt the silica back to base materials.
Might be similar for carbon fibre. Through a chemical reclamation process. This only issue I think it would face here is. Is there process is not widely known about. The few that do know have extremely limited reach. Sphere of influence and all that jazz. Rule 1 know your battlefield. If there was an industry for reclamation? If it solely focus on turbine blades? Then whatever it can recover? could go towards funding?

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Hi Roddy: A perfectly-balanced rotor is not a strict requirement if you do not have a hard center. Also, such a problem is well-known in wind energy, often forming a paint bubble full of water at the blade tip. It’s not a concern for an experimental turbine used in fair weather. It’s a concern for turbines in long-term service that are exposed to the entire spectrum of weather conditions, often when there is nobody around to even see what happens.

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Just for some perspective. Eg.

Fibre glass once processed? can be reduced back to sand.
If resourced correctly? Even builders requirements for aggregate can be meet. With a shortage of building sand. It might just plug the gap?
I can see a multitude of applications. provided the resins can be removed?
Environment clean up would be the next step.

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