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We could quite possibly catch solar winds as a means for endless energy, and though it sounds like science fiction, we have the materials to do this now.

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Instead, its goal was to stabilize the satellite and collect the electrons that make up a portion of the solar wind, using them to create an electric potential. That potential is then used to generate a current along a very long one-centimeter thick copper wire that's pointing towards the sun 

A flowing electric current generates a magnetic field, so now there's a cylindrical magnetic field around this copper wire, and that deflects more solar wind electrons towards a spherical metallic receiver.

A tiny bit of this collected energy is cycled back to feed the current in the magnetic field, but most of it can be collected as energy. That energy would then be transmitted wirelessly using an infrared laser pointing it to a dedicated receiver on earth, or wherever the power is needed.

Since infrared energy passes through the atmosphere pretty easily, a laser using wavelengths in the infrared range would be the most efficient for transferring energy. The authors calculated that with a 10-meter-wide sail and a 300-meter-long wire, a satellite could capture and transmit about 1.7 megawatts of energy. That's enough to power about a thousand homes. But if this same technology was scaled up, with a wire 1 kilometer long and a sail nearly 8,500 kilometers across, then it could generate a billion billion gigawatts of energy. 

Now that sounds like a lot. Because it's a lot. It's about a hundred billion times what the entire earth used in 2010. Now that's assuming we could figure out how to build something that huge in space. This is very big. 

Aside from the mind-blowing amounts of energy a Dyson Harp satellite could supply, it has some other big advantages. For one, it's self-sustaining since it uses the collected energy to power the magnetic field itself. The construction in its smaller and more reasonable form is simple and is designed to withstand degradation from the powerful solar wind. What's more, we could actually make one right now, with present-day materials and technologies. And it would be cheaper than the equivalent amount of solar panels since copper is cheaper than photovoltaic panels based on 2010 numbers. 

But, there is a problem.  To be able to capture the most energetic electrons from the solar wind,  the satellite would have to be positioned a really long way away from earth. Specifically, it would need to be above the plane of Earth's orbit. getting a 4-ton satellite that distance out is a difficult and expensive prospect, and there would be no chance of maintenance or repair.

But even that is not the biggest hurdle. Even though lasers are designed to point all of their energy in a really thin beam, they do spread out ever so slightly by just a fraction of a degree. So over the huge distances we're talking about here, the power laser would eventually spread out so much that by the time it reached the earth, it would be thousands of kilometers wide. The smaller scaled version of the satellite would supply two megawatts of energy. An amount that would be no more powerful than moonlight when spread out over that distance. 

A more powerful beam would be just as wide, but would then be showering powerful infrared radiation over a huge area of the earth, which is not ideal. Now to capture and refocus the widened beam, engineers estimate that you would need a flawless lens anywhere from ten to a hundred kilometers across. Which at the moment, is beyond what we can reliably pull off, making it the one part of this that we couldn't just decide to do like a tomorrow if we wanted to. 

So theoretically, solar wind power has the potential to solve many of our energy problems on earth and in space, and we're closer than you might think to being able to tap into the sci-fi energy source, but until we can find a better way of transmitting the power over millions of kilometers, a working Dyson Harp satellite is simply out of reach.

Now we humans would not have bold ideas like this one without a lot of creativity, and skillshare wants to help creative folks hone their ideas and get them out into the world. If you, like us, want to do that on YouTube, you might like their course Youtube success: Script, Shoot, and Edit with MKBHD, who you might know as Youtuber Marques Brownlee. An annual subscription to skillshare is super affordable at less than 10 bucks a month, and it gives you unlimited access to the classes and communities that are right for you. And if you're one of the first thousand to click the link in the description, you can get started with a free trial, so thank you for your support.