Microsoft&39's real-world power consumption measurements for several browsers with a news site open.

After some real-world tests, Microsoft has concluded IE9 is the most energy-efficient of the major browsers on the market.

Microsoft compared its new browser with Opera 11, Firefox 4, Chrome 10, and Safari 5 on an Intel laptop, measuring how many watts the machine consumed with the browser idling, showing a news site, and running graphics-intensive Web tests.

The upshot: IE9 is the most efficient in the test, meaning it'll take the smallest toll on the battery.

"We hope and encourage the industry and other browser vendors to follow us on the path to a more power efficient Web," said Walter VonKoch, Matthew Robben, and Jason Weber, three Microsoft personnel involved in power and performance matters.

There's plenty wiggle room in the study, of course--your mileage may vary in any number of ways. The tests were on Windows 7--but how does Safari fare on a Mac IE9 has lots of hardware acceleration features that can reduce power consumption--but Firefox 4 and later other browsers offer some hardware acceleration on Windows XP, too. Microsoft's selection of Web sites may not represent the sites where you actually spend time. Different computers have different power consumption and power-saving characteristics. And of course in the real world, most people run more software than just a browser.

But the results are valuable nonetheless. I applaud Microsoft for setting up a test and for caring about power consumption.

It makes sense to cut power usage from an environmental and financial perspective, needless to say, but better battery life is more important for the average person. Students moving around campus and traveling businesspeople don't always have the luxury of a power outlet on hand.