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Apple's Solar Power Patent: Sun Powered Mac, iPods, iPhones in the Future


Apple's winning more patents all the time, but the latest one is fascinating: It's the first patent for solar powered portable devices that's been awarded to the company. Added to the company's other solar patents, it looks like sunny future for Steve Jobs' company.

Apple's patent is very specific—as you may imagine the field of solar charging and portable devices is heavily patented already, and portions of the technology have been IP protected for years. But what Apple's trying to do is work out a way to reliably and stably charge the rechargeable batteries in a mobile device like an iPhone, iPad or MacBook.

The subtlety here is that batteries in these devices are pretty fickle beasts. They like to be charged and discharged in a particular way, across a certain voltage and with particular power drain (or charge) parameters—this is how they perform best, and last longest. But charging a sensitive high-tech lithium cell from solar-powered sources doesn't necessarily meet up with these needs—the sun is an unreliable friend, delivering variable power from minute to minute even under near-ideal solar charging situations.

Hence Apple's invention, which inserts a power control circuit between the source of power (solar cell) and the destination (the battery). Essentially the controller is smart enough to monitor the "dirty" electrical power dribbling from the solar cell, and polish it so it's cleaner, smoother and better for charging the rechargeable cell. And the patent's not just limited to this behavior—Apple recognizes that of course mobile devices will get charging power from other sources, and has worked out how to combine this smart solar charging with other power needs.

If you're scratching your head at this point, and pondering that this sounds kinda obvious, let me point out a Douglas Adams quote: Comparing the discovery of gravity and the invention of the (seemingly obvious) catflap, it's important to note that as far as gravity is concerned "they even keep it on at weekends. Someone was bound to notice sooner or later. But the catflap...ah, there is a very different matter. Invention, pure creative invention." It takes an invention like this to make something new happen. And remember that Apple is one of the world's largest vendors of portable electronic devices—if it takes a smart step in a green direction, like this patent, then it has important ecological implications. And where Apple treads, others follow.

To read more news on this, and similar stuff, keep up with my updates by following me, Kit Eaton, on Twitter.