How many 35w PC's 100 or 1000?Work PCs on all the time - even across the whole business the energy saving of turning 35W HP Minis off vs inconvenience of turning them back on, and possible risk of issues happening on bootup isn't worth it.
Home PCs only on when required - with SSDs is all my PCs I don't even bother with hibernate anymore as clean boot and launching apps is plenty quick enough.