if you're at all like me this is what you do with the sunny summer weekends in san francisco you build experimental kite powered hydrofoils capable of more than thirty knots
and you realize that there is incredible power in the wind and it can do amazing things and one day a vessel not unlike this will probably break the world speed record
but kites aren't just toys like this kites i'm going to give you a brief history and tell you about the magnificent future of every child 's favorite plaything
so kites are more than a thousand years old and the chinese used them for military applications and even for lifting men so they knew at that stage they could carry large weights i'm not sure why there is a hole in this particular
these two fellows came along and they were flying kites to develop the control systems that would ultimatelyenable powered human flight so this is of course orville and wilbur wright and the wright flyer
and their experiments with kites led to this momentous occasion where we powered up and took off for the first ever twelve second human flight
wrote this seminal paper that was completely ignored in the journal of energy about how to use basically an airplane on a piece of string to generateenormous amounts of electricity
the real key observation he made is that a free flying wing can sweep through more sky and generate more power in a unit of time than a fixed wing turbine
so turbines grew and they can now span up to three hundred feet at the hub height but they can't really go a lot higher and more height is where the more wind is and more power as much as twice as much
to now we still have an energycrisis and now we have a climatecrisis as well
you know so humans generate about twelve trillion watts or twelve terawatts from fossil fuels and al gore has spoken to why we need to hit one of these targets
and in reality what that means is in the next thirty to forty years we have to make ten trillion watts or more of new clean energy somehow
the majority of it is in the higher altitudes above three hundred feet where we don't have a technology as yet to get there
so this is the dawn of the new age of kites this is our test site on maui flying across the sky i'm now going to show you the first autonomous generation of power
by every child 's favorite plaything as you can tell you need to be a robot to fly this thing for thousands of hours it makes you a little
and here we're actually generating about ten kilowatts so enough to power probably five united states households with a kite not much larger than this piano
and the real significant thing here is we're developing the control systems as did the wright brothers that would enable sustained long durationflight and it doesn't hurt to do it in a location like this either
so this is the equivalent for a kite flier of peeing in the snow that's tracing your name in the sky and this is where we're actually going so we're beyond the twelve second steps and we're working towards megawatt scale machines that fly at two thousand feet
and generate tons of clean electricity so you ask how big are those machines well this paper plane would be maybe a
so that is audacious you say i agree but audacious is what has happened many times before in history this is a refrigerator factory churning out airplanes for world
so really this is a story about the audacious plans of young people with these dreams there are many of us i am lucky enough to work with thirty of them and i think we need to support all of the dreams of the kids out there doing these crazy things thank you
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