Badly programmed websites drain your batteries
Optimization brings up to 30 percent energy savings for mobile devices
Stanford University researcher Narendran Thiagarajan http://stanford.edu found that poorly programmed websites reduce the battery life of mobile devices. Unnecessary code ballast can increase energy consumption by up to a third, even with simple websites. On the other hand, by optimizing web pages, it was possible to identify an almost equally high potential for energy savings.
Accessing Wikipedia costs one percent
For the test, Thiagarajan and his team coupled an Android smartphone with a multimeter and then called up 3 popular sites via a 25G connection. Charging the mobile Wikipedia site already consumed one percent of the battery capacity. Calling up the Apple homepage, of which there is no optimized version for tablets and telephones, on the other hand, consumed 40 percent more "juice".
However, this method was not clean enough for the researchers, as it also mixed the energy consumption of the download of the page elements into the result. So they saved the pages locally in advance for a second attempt in order to only record the battery load that results from the display in the browser.
Unused elements as power guzzlers
The experts were able to determine that many of the websites that were "made mobile" also used numerous code components and elements that were only used to a limited extent or not at all. For example, the Wikipedia site accesses a larger library with various navigation mechanisms via Javascript, but only uses one of them to expand and collapse content.
By optimizing the Javascript file and making changes to the stylesheet and images, they were able to reduce the effort for rendering the page from 35 to 25 joules, which corresponds to a saving of 29 percent. The mere fact that only the required components of the navigation library were loaded made up a large part of this difference with 5,5 joules.
From this, the researchers draw the conclusion that it is not just beautiful page design and fast loading times that are decisive. They assume that users will avoid power-hungry websites in the long run. Their results will be presented later this week at the World Wide Web 2012 Conference http://www2012.wwwconference.org in Lyon, France, which opened the day before yesterday, Monday.
(ck) 18.04.2012/XNUMX/XNUMX
.