In Windows XP enabling Hibernate option was a very easy task, but we have to follow a different approach to do the same job in Vista and Windows 7.
If you are not aware of Hibernate feature, Hibernation is a power-saving state designed primarily for laptops. While sleep puts your work and settings in memory and draws a small amount of power, hibernation puts your open documents and programs on your hard disk and then turns off your computer. Of all the power-saving states in Windows, hibernation uses the least amount of power. On a laptop, use hibernation when you know that you won’t use your laptop for an extended period and won’t have an opportunity to charge the battery
during that time.
So if you are really going to use this feature then you need to enable it by doing a simple procedure as mentioned below:
1. Open Command Prompt with Administrator rights. To open Command Prompt, type CMD in Start menu and then hit Ctrl + Shift + Enter to open the Command Prompt with Admin rights.
2. Next, type the below command and hit enter:
powercfg /hibernate on
3. Type exit and hit enter to close the Command Prompt.
4. If you can’t see the Hibernate option in Start menu then do the following tasks:
A. Type Power Options in Start menu and hit enter.
B. In the left pane, open the link labeled “Change when the computer sleeps” and then open the link “Change advanced power settings”.
C. Under the Advanced Sleep options, expand the Sleep tree and turn off Hybrid Sleep.
D. Now go back to Start menu to see the new Hibernate entry.