I think kitepower have a great position. They go for mobility, even If I think the ground unit could be a lot smaller. They have a middle range power output of 100kW which is reasonable.
They have what they call the kite control unit for automatic launch which is quite simple, soft wing.
Weak point might be the durability of the wing maybe.
Then come the price? Is it for sale, or do they sell the service? Just shipping the whole thing would cost a lot. They do not speak about price yet but if they want to be in their time-line which is one year from now, then they shall start to market the whole thing, shift the website from classical team, tech, our goal and so on to a real selling website.
I am just thinking is this possible or not, technically. I am not in a position to say something accurate about profitability, but I believe there is potential to be profitable with scale.
About Ampyx: I believe their rigs may produce power like they claim, and launch and land is possible. My major concern is reeling out tether during a hot launch. My second concern would be handling offshore conditions and maintenance costs. Profitability? I dont have a clue
At AWEC2019, Uwe Fechner presented the release of a dataset from kitepower project testing from between 2011 and 2015. In totoal 81 physical properties were loggedâŚ
So I asked if the data on kite pod steering current demand was included in the set.
If anyone knows where that data is ⌠Iâm very interested.
Rod, indeed there is a compilation comprising data of 42 flights with three different wings. As it is not yet the definitive document I suggest you to ask to Roland for this paper. Perhaps he could provide a copy to the forum.
TBH Iâm speculating here⌠I havenât gone through the data-set yet and⌠It may be that I asked for results from the recent tests, which will be confidential.
Iâm just going on my hunch⌠which says⌠Itâs going to require a hefty load of power to shift the brake or steering line when youâve got such an enormous kite going so fast in high wind.
And because itâs just a hunch I left the swearing out of that description.
Single line, large soft kite control may well be easy with the right bearings and gearing.
That is exactly what you were already referring to (see below):
When flying KitePower collects a lot of data that is useful for all AWE actors of which those using yoyo mode. All AWE companies make a great job. But one can see the realizations as preliminaries towards a possible better and more expensive design. Now the intermediate (not utility-scale) markets issues can be who will buy an automated system flying crosswind by a low elevation angle as a required condition is the lack of inhabitants in the production area. This is not easy because if the system is connected to the local network the installation should be close to existing equipment such as diesel generators, and so toâŚinhabitants. It is far more easy to implement a conventional wind turbine, or even a stationary AWES.
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The FAA (and ICAO) will only stop AWE players who violate airspace safety, as adjudicators of all safety complaints made by aviation and other stakeholders. Kites have been regulated by the FAA for generations, as carefully documented on the old Forum.
The core import of FAA AWE regulation is not the policing function, but the intimate connection to Aviation Safety Cultureâs best practices incumbent on our AWE Pilot Community. Every major AWE plant will long require a PIC (pilot-in-command) who understands airspace and aviation safety.
Those AWE ventures that neglect Aviation Safety Culture will not be insurable, at a minimum; relegated to remote niche markets, until safer AWE overtakes those markets too.
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Hello Pierre & Rod,
I am still working on the data set, a.o. because I was able to retrieve even more flight recordings (now 47 individual flights). Authors are Uwe Fechner and myself. This will all be for the 20 kW pumping kite power system of TU Delft, which has a nominal average electrical power of about 7 kW. The data set comes with a detailed report which researchers can use to develop a physical model of the system. In this time period we used three different kites: Mutiny V2 with 25 m2 wing surface area, Genetrix Hydra 14 with 14 m2 surface area and TU Delft V3 with 25 m2 surface area. The report also links to previous publications from our research group. I will also include detailed photo footage for most of the flights.
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This topic is not new. What has happened since? The current market is provided by Kitewinder as in the past. Then Skysails has scaled his SKS PN-14 to 100 kW range, starting to sell some units. This company goes to the essential (if not the single) goal in my opinion: reaching high altitude winds that cannot be harnessed by conventional wind turbines which are limited to 200 m.
Just as a tree starts out as a seedling, and just as regular wind turbines started out much smaller than todayâs giant turbines, it seems to me that anything airborne will start out by finding a size and height that works today, considering the current state of the art, then worry about high altitudes as experience is gained and what really works well, and what doesnât doesnât work so well or presents problems is learned. I donât think it makes sense to target the stratosphere right now, but maybe soon! 
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Hi Doug: AWE is no longer a newborn baby, although being far to be mature. Altitudes of several hundred meters have already been reached, notably by Skysails (tether length 800 m) and Kitepower. In any case we are still very far from the stratosphere.
Designing an AWE system to harness high altitude wind energy (HAWE) should be its single goal, and is not the same as designing an AWES only in order to exploit winds also reachable by HAWT and which leads to a sure dead end.
I dont agree on this. Reaching high altitudes can be a worthwhile goal, but not the only avenue for AWE to succeed
Hello Pierre: I didnât want to use that tired old ânewborn babyâ term, which I see as just a repetitive talking-point-excuse for zero results from the circular firing squad. My only point is that usually, progress follows an organic path upward, rather than starting at a fully-developed art. The patient is now a recalcitrant young teenager, prone to rebelling against our âauthorityâ. It will always be a newborn for those unable to think their way out of a paper bag.
I see your point here. Maybe like space flight was a quantum leap from airplanes, and did not use wings or âliftâ, for the most part. So you are saying miles-high AWE, should such ever emerge, may not follow anything learned in low-level AWE. That takes us back to the 3 blind men trying to describe an elephant that does not yet exist.
Well, if everything you said is true, most current efforts are doomed, and we should all âstep up our gameâ to âhigher heightsâ, and start with a clean slate.
Hi Doug: forget about your elephants and your three blind men for a moment. And face reality with the Skysails example in the real world and I just cited, considering that massive R&D in AWE field is now approaching 15 years.
Skysails (tether length 800 m): at an elevation angle of 30 degrees, the altitude is 400 m.
400 m is 2 times more than the highest HAWT. Not 2 times less, but 2 times more. And it is now.
400 m is 20 times more than the altitude reached by any torque transfer rotary device. Not 20 times less, but 20 times more. And it is now.
I think the first comparison gives an idea of the altitude that AWES is already reaching.
I think the second example gives an idea of the path not to follow if you want to reach high altitudes.
OK well youâve sort of lost me now. It sounded like you were saying nothing currently being pursued is going to work out. Now it sounds like youâre saying the opposite: skysails just has to go bigger and kite-reeling will prevail in a high altitude application. So the 3 blind men know all about the elephant and have its trunk as a tether, and it is a kite flying around pulling the string from the stratosphere?
Currently we are indeed far from something that could work at utility-scale.
I have been commenting for some time on the overwhelming superiority of Skysails: 92 kW and 400 m altitude. Perhaps only KitePower approaches these values. Both are kite-reeling. As a result after 15 years, kite-reeling systems prevail in AWE field. These values are also quite small for current HAWT, and space use remains an issue. Also we donât know about wear due to reel-in and reel-out phases, and so on.
Stratosphere: from 10 km to 50 km.
10 km is 25 times more than 400 m (current altitude for Skysails).
Excess wear has been observed in some AWE videos.
Marine shipping (fishing, towing, anchoring) knows all about how to manage line wear. Goldstein covered a great method. Properly done, itâs a solved problem.
Cableways run for years at high loadings using Bull Wheels.
Bull Wheels are an old solution to excess line wear; one of many available methods to AWE. Bull Wheels can work for AWE as well as they do anywhere.
Courtesy: Dave Santos CTO, JAL
Of course.
Once again, I recognized the âvoiceâ of daveS in this post.
Glad you mentioned it rather than me.
Chairlift haul ropes go slowly, and have a built-in number of cycles expected before replacement is recommended. This is not new information for us.
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One of the bullwheels is usually attached to a cable tensioning system, which is usually either hydraulic or fixed counterweights.
In AWE field bull wheels would be similar to a rope drive transmission, not a reel-in/out yo-yo system. And also they require a cable tensioner system.