Jun/112
Tablets and On-Device Solar Power
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.
Jan/107
A Solar-Powered PC for 2010.
I’d love to get out an do another Solar Computing Tour in 2010 but I’ll have to plan it carefully. Our new baby is due in March so maybe I can pull a long weekend together in late August but we’ll have to see how things go.
It doesn’t stop me thinking about solar computing though and in this post I’m going to compare a set of devices and some technologies that will be important for the job of Solar PC 2010.
Before I do that I want to highlight a few things that really haven’t changed much in the last 3 years. It’s a sad story of minimal progress.
- Solar panels – NOTHING has changed. They’re still expensive and inefficient.
- Battery Tech – NOTHING has change. They are still expensive and use the same technology as before.
- Operating system choice – Nothing has really changed. If you want to work efficiently you need to choose the same OS as you use on the desktop. Mobile operating systems have come a long way but there are still too many potential roadblocks for the average productivity user. Windows 7 is nice but compared to XP it’s less efficient which in my book, makes it the best choice for efficient and productive mobile computing.
- Screen technology. Outdoor users are still fighting the sun with LED backlights although this is a great step forward from the CCFL backlighting I used in 2007. Transflective screens are coming in 2010 though. See below.
- Weather – Ah, there’s something that hasn’t changed much either! Still, constant chaos. (Thank goodness!)