Apple promises update to fix MacBook Pro battery problems

Posted Jan 13, 2017 by James Walker
Apple is preparing to release a software update for the MacBook Pro that should address some of the battery problems customers have been experiencing. It comes after the company investigated issues that led to the laptop failing Consumer Reports' tests.
Apple MacBook Pro (2016)
Apple MacBook Pro (2016)
Apple's had a tough time with its new MacBook Pro. Although sales have been very strong, many customers have reported being unable to reach Apple's battery life claims. Last month, the company removed the "estimated time remaining" meter from macOS as a result, without explaining what's going on.
The company is now working on a software update that should improve things for some users. After the Pro became the first MacBook not to receive a Consumer Reports recommendation, Apple worked with the testing team over the holidays to figure out what went wrong. In its labs, Consumer Reports experienced wild battery life swings, varying between tests by up to 5x.
It turns out the test scores were down to two problems. First, Consumer Reports disabled a hidden Safari setting to prevent the browser caching webpages. This feature downloads parts of webpages so they can be retrieved faster in the future and is standard in all modern browsers.
Consumer Reports said it disables caching on every laptop it tests, even though users will have it turned on. Caching improves battery life because the computer doesn't need to make so many network requests.
After working with Consumer Reports, Apple ascertained what caused the inaccurate battery life readings the labs observed. It found that disabling Safari's caching triggered a rare bug in the browser that led to the unpredictable battery behaviour. The company reported its discovery to Consumer Reports which agreed to run the tests again with a patch for the problem installed. It evaluated the models on test again and confirmed they "all performed well," enabling it to make a recommendation.
"The process we followed with Apple is the same process we follow with any manufacturer when we discover a significant problem," said Consumer Reports.
"We shared our test results with the company so it could better understand our findings and deliver a fix to consumers. Since Apple made a fix, we retested the laptops. Now that we’ve factored in the new battery-life measurements, the laptops’ overall scores have risen, and all three machines now fall well within the recommended range in Consumer Reports ratings."
Considering that Consumer Reports saw battery durations run anywhere from 3.75 hours up to 19.5 hours, the impact of the Safari bug was quite severe. Once fixed by Apple, the MacBook settled down to an 18.75 hour runtime under test conditions.
The software update that led to the improvements should reach all MacBook Pro owners in the next few months. It is in testing under Apple's Beta Software program now and will improve the power consumption of Safari. The current release is macOS Sierra 10.12.3 Beta.