Is there ongoing work in the kernel team to improve battery life under linux?

I have read in some forums that the kernel team is working on improving battery life and energy efficiency in Linux. Unfortunately our community really lags behind Windows and Mac in that regard. I would like to read about the reasons why this difference exists with other platforms.

Is it purely due to closed hardware specs from vendors or does it has to be with kernel design issues? Apple devices with Unix cores have amazing battery times, but they also design their own hardware. I just want to understand these issues in a less technical way.

I know that recent kernel updates in Ubuntu have improved the battery life in most computers, but I was wondering if there is still development going on and where can I read more about it.

A lot of effort was put into the Precise 12.04 LTS release to address a lot of the major power sucking issues that we had identified, such as the Intel i915 rc6 GPU power saving, PCIe ASPM, processes that caused too many wakeup events and also to reduce disk I/O (for example daemons writing to the disk too frequently).

There is a Wiki page devoted to this work: https://wiki.ubuntu.com/Kernel/PowerManagement

The newer Quantal 12.10 release will be using the newer 3.5 (or even possibly 3.6) kernel will mean we pick up a lot of upstream power management savings, for example in the recent ACPI driver.

Unfortunately, trying to make Ubuntu as efficient as closed proprietary hardware is difficult without full disclosure of how the hardware works and is configured. For example, powering down some devices may require special knowledge of the underlying physical components.

Power saving is a non-trivial issue, and sometimes bugs in the firmware (BIOS) can lead to sub-optimal configurations, or maybe drivers are based on binary blobs which we have little or no control over.

As for on-going work, there is a project page where bugs can be filed against mis-behaving applications that allow us to focus on fixing power sucking issues:

https://bugs.launchpad.net/ubuntu-power-consumption

I also have some blog articles on this work:

http://smackerelofopinion.blogspot.co.uk/search/label/power

Hope this helps.