Sony Vaio sleep mode

As an experiment I left my Vaio in sleep mode overnight. What this means is that it still uses power to keep the RAM active - but how much does it use? I had no worries about it running out as I knew that should it do so it would switch to hibernation mode and move the contents of the RAM to the non-volatile hard drive.

However I have noticed a drain in power when it's been technically switched off; so how would it fair?

Roughly 15 hours of sleep and the battery drained by 15%. With it set to switch at 5% battery life I should have 95 hours of sleep or about 4 days. This means I can leave it in sleep mode both overnight and at the weekend provided I do nothing with it.