Power management in 64 bit 14.04
From Karnataka Open Educational Resources
Depending on the processor-type, 64-bit Kalpavriksha(or any 64-bit GNU/Linux system) may consume more power and drain battery quicker than its 32-bit counterpart. This can be reduced a little by tweaking power settings or using power saving tools like TLP, powertop, etc.,. are available for GNU/Linux systems. And TLP(no one knows for sure what this acronym stands for) can be installed with below commands --
sudo add-apt-repository ppa:linrunner/tlp
sudo apt-get update
sudo apt-get install tlp tlp-rdw
sudo tlp start
If this is already installed in your system, below are some of the links which can help you further to reduce power consumption and increase battery life of your laptop.