Asus Laptop Windows 8 battery life

Hi,
I have an Asus Laptop with the following specs: RAM- 8GB, Intel i3-3220 and Windows 8.1.
At first it had Windows 8 and when fully charged it could stay for 6 hours but now after the upgrade to Windows 8.1 battery only stays for 2 hours. Does Windows 8.1 consume more power? Can I reduce power consumption?
