How close are we to powering our tablets with on-device solar cells?
In a recent test I ran a tablet connected to the internet at an average 200 mW. That’s screen off, wifi connected and polling in the background to update emails, location, twitter and other processes. It’s nothing really surprising because most of the tablets are built on smartphone technology. With the screen on though, usage will jump about 5-7x and if you push the CPU and add 3G you can reach 20X that power drain. Still, running everything in 4W is still impressive. It’s just a shame that 20-30% of the in-use power and about 70% of the idle power when the screen is on is used by the screen itself. LED-backlit technology is getting better but only in small amounts. What if you could use ambient light for the screen, just as we do when we read a paper book?
Pixel Qi is one company that are developing these ‘transflective’ screen technologies and in an interesting interview I saw today, Mary Lou Jepsen, the founder, talks about using solar energy to power a low power tablet with a Pixel Qi screen. By combining transflective screen technology with a low power tablet, you’re talking about 1W of power in idle, screen-on situations.
