I guess this means that this project is dead or not viable for some reason, and they're being nice and releasing their work. Good job Google!
As an aside, it should be law to release any firmware, code, and backend services code for any device that is no longer fully supported by the manufacturer.
Let other people play with your dead things and reduce the barrier for new innovation on top of them.
Google stopped funding Makani several months back.
I'm not sure how applicable most of this code will be for other kite power companies. The Makani "kite" turbine was 2000 lbs. It definitely required Google-level funding to develop which is now gone. None of the remaining kite power companies that I'm aware of have the kind of significant funding required to develop this - ours ran out of money late last year.
Essentially the same code could run Makani's smaller machine, the 20 kilowatt "Wing 7", with a 7.8 meter wingspan and a mass of 60 kg. Many of the existing kite power companies are working on machines of this scale.
But we did have the luxury to design and build the system from the ground up, whereas scrappier startups might have to cobble together existing components. Hopefully they will be able to utilize some of the materials we've just released.
So what's to stop me cobbling together something like the Wing 7 and just leaving it unattended in a field to launch and generate whenever the wind conditions are suitable?
If I did, and I got typical government subsidies for wind power, I might earn $10k/year. That ought to pay for all the machines parts if I buy everything hobby grade from AliExpress. The 2nd year is pure profit assuming the craft lasts that long.
So that leads me to suspect the key issue is the various control algorithms can't be made reliable enough to run for years and years without crashing under any combination of gusts and wind conditions. Am I along the right lines of the issues?
The issue is the tumbling cost of regular wind turbines, even offshore. If you have such a field, you would build a turbine, not a kite.
So yes, you could make a profit. But there is an alternative source of technology that makes the same power and has become really profitable in the last 10 years.
Makani engaged early with FAA and we had a great working relationship. This enabled us to move out of China Lake (where we were using the military's restricted airspace, which didn't require FAA approval) and out into the public airspace in Hawaii. We did several test flights in close collaboration with FAA observers, developing a color scheme for the tether and a lighting system for the kite and ground station that were deemed adequately conspicuous. We also held a round-table with local pilots to get their input. Ultimately we operated under a "determination of no hazard" that classified the Makani system as an obstruction, something like a large radio tower.
It depends on how high it gets, because even high buildings/structures can be problematic. (They need a blinky light of course, but maybe more importantly a radar reflector.)
As an aside, it should be law to release any firmware, code, and backend services code for any device that is no longer fully supported by the manufacturer.
Let other people play with your dead things and reduce the barrier for new innovation on top of them.