UPDATE: Turns out the Surface 2 Pro was shipped with bad firmware.
Still, over 11 hours of battery life browsing the web on WiFi? That means the Air is somehow producing nearly two times the battery efficiency of the best hardware and software combination Microsoft can muster, for what I consider to be the most common usage pattern on a computer today. The Surface Pro 2 has a 42 Wh battery, which puts it closer to the 11 inch Air in capacity. It's a real computer, too, using the latest Intel technology. The screen is somewhat lower resolution and not touch capable, of course, but under the hood, the i5-4200u CPU and LPDDR3 RAM are nearly the same. Nearly 7 whole hours of WiFi web browsing for a real computer in tablet form factor … that's not bad, right? Let's see how the 2013 MacBook Air does, which spec-wise is about as close as we can get to the Surface Pro 2. That's a decent increase, I suppose, but I was hoping for something more like 8 hours, something closer to doubling of battery life – to bring the Surface Pro in line with other tablets. So WiFi web browsing battery life, arguably the most common user activity there is on a computer these days, goes from 4.7 hours on the Surface Pro to 6.7 hours on the Surface Pro 2, a 42% increase. Still, I was hopeful that the first Surface Pro with Haswell inside would produce giant gains in battery life as Intel promised. Granted, this is a classic Intel x86 box we're talking about, not some efficient ARM system-on-a-chip designed to run on a tiny battery. My main complaint with the Surface Pro is the incredibly lackluster battery life.
Because it is a blazingly fast, modern Intel machine, I like to use the Surface Pro to predict where tablet performance ought to be for everyone in 2 to 3 years. I can't wait for the iPad 5 this week (I'll be ordering three), and my Surface Pro 2 should arrive this week too. I believe that most things we think of as "computers" will be de-facto tablets, either in our pocket, in our hands, possibly even mounted on our wrists or forearms. I've become a huge fan of touch computing. Why Does Windows Have Terrible Battery Life?