E Ink and their partners recently demoed some new products at this year’s SID Display Week, including a new 32″ solar powered E Ink poster called the Solis 32 Display.
It uses E Ink’s full-color Spectra 6 technology, which is part of their digital signage line so it isn’t directly related to ereaders, but it’s interesting to see E Ink technology paired up with solar power.
I always thought it would be cool to have a solar powered ereader, or better yet, a solar powered case that slowly charges your ereader’s battery when you aren’t using it (there actually was a product called the SolarKindle for the Kindle 4 back in 2012, but the concept never caught on).
E Ink’s low power displays are a good fit for solar power since energy isn’t required to display an image or text on the screen; power is only required when changing the content on the screen.
The Solis 32 Display has a solar array mounted on top of the screen that can draw enough energy from regular indoor lighting to change the display up to 3 times per day. They claim it has “unlimited” battery life under normal store lighting (the fine print on the datasheet says it requires 1000 lux for 12 hours a day to achieve that).
The display has WiFi built-in to change the image wirelessly via an app, and it takes approximately 18 seconds to change the image. The display resolution is 2560 x 1440, which equates to 93 ppi on the 31.5″ screen. They claim it supports 65,000 colors so that a massive increase over E Ink’s Kaleido 3 screens used on ereaders that only support 4,096 colors.
These E Ink “posters” are being marketed for retail applications obviously, but it would be cool to see other E Ink products getting solar powers in the near future too.
I bought a portable solar panel for a five day camping trip to charge my Apple Watch, iPhone and battery back. It worked surprisingly well and I brought it again to a family farm in Brazil, where it was very useful when power was down for days, though less efficient since everyone else there also wanted their devices charged. It would be cool if more electronics natively packed in solar panels. Garmin has it in some of their high end watches and I’m always curious why Apple hasn’t implemented it in their Apple Watch Ultra.
The problem with solar panels is that you would need a bigger panel that the device to produce a meaningful amount of power to charge up the device. Also, you don’t normally leave a device sitting in the sun as the heat can ruin the device. So, a case for an ereader would not be big enough nor protect the device from the heat. Best thing to do is what the other post suggested, get a power pack with a foldout panels to charge up your ereader and other devices.
People severely underestimate how bright outdoor sunlight is, and overestimate how bright their room is. The standard office space is ~500 lux or half the amount quoted to do 3 page refreshes – that means not even 2 page turns a day on your solar e-reader in a brightly lot office, much less the average home which is much less well lit. Unless you’re leaving your solar e-reader outdoors in direct sunlight, this isn’t going to work out.