Why is my CPU use up around 100% just running Chrome and Mail.app? Fans are running at ~50% since I turned my MBP on this morning and this is a snapshot of the CPU use, it's crazy for 40 tabs open (I often have >100 tabs with several devoted to thread hungry social media sites like twitter and facebook).

Processes in Activity Monitor sorted by CPU Time:


Processes in Activity Monitor sorted by % CPU (changes order dramatically each few seconds):
I had a similar problem with fans and battery death, and solved it by removing Gmail Offline from Chrome. It was going CRAZY whenever Chrome was running. You can remove it by opening Chrome Apps (the grid of 9 dots in the top left corner of Chrome), right click on the Gmail Offline icon, and Remove it. Much better